A review of alternatives to di (2-ethylhexyl) phthalate-containing medical devices in the neonatal intensive care unit

Prevalence and clinical implications of heightened plastic chemical exposure in pediatric patients undergoing cardiopulmonary bypass

BACKGROUND

Phthalate chemicals are used to manufacture plastic medical products, including many components of cardiopulmonary bypass (CPB) circuits. We aimed to quantify iatrogenic phthalate exposure in pediatric patients undergoing cardiac surgery and examine the link between phthalate exposure and postoperative outcomes.

STUDY DESIGN AND METHODS

The study included pediatric patients undergoing (n=122) unique cardiac surgeries at Children's National Hospital. For each patient, a single plasma sample was collected preoperatively and two additional samples were collected postoperatively upon return from the operating room and the morning after surgery. Concentrations of di(2-ethylhexyl) phthalate (DEHP) and its metabolites were quantified using ultra high-pressure liquid chromatography coupled to mass spectrometry.

RESULTS

Patients were subdivided into three groups, according to surgical procedure: (1) cardiac surgery not requiring CPB support, (2) cardiac surgery requiring CPB with a crystalloid prime, and (3) cardiac surgery requiring CPB with red blood cells (RBCs) to prime the circuit. Phthalate metabolites were detected in all patients, and postoperative phthalate levels were highest in patients undergoing CPB with an RBC-based prime. Age-matched (<1 year) CPB patients with elevated phthalate exposure were more likely to experience postoperative complications. RBC washing was an effective strategy to reduce phthalate levels in CPB prime.

DISCUSSION

Pediatric cardiac surgery patients are exposed to phthalate chemicals from plastic medical products, and the degree of exposure increases in the context of CPB with an RBC-based prime. Additional studies are warranted to measure the direct effect of phthalates on patient health outcomes and investigate mitigation strategies to reduce exposure.

The mitochondrial link: Phthalate exposure and cardiovascular disease

Phthalates' pervasive presence in everyday life poses concern as they have been revealed to induce perturbing health defects. Utilized as a plasticizer, phthalates are riddled throughout many common consumer products including personal care products, food packaging, home furnishings, and medical supplies. Phthalates permeate into the environment by leaching out of these products which can subsequently be taken up by the human body. It is previously established that a connection exists between phthalate exposure and cardiovascular disease (CVD) development; however, the specific mitochondrial link in this scenario has not yet been described. Prior studies have indicated that one possible mechanism for how phthalates exert their effects is through mitochondrial dysfunction. By disturbing mitochondrial structure, function, and signaling, phthalates can contribute to the development of the foremost cause of death worldwide, CVD. This review will examine the potential link among phthalates and their effects on the mitochondria, permissive of CVD development.

Ongoing exposure to endocrine disrupting phthalates and alternative plasticizers in neonatal intensive care unit patients

Due to endocrine disrupting effects, di-(2-ethylhexyl) phthalate (DEHP), a plasticizer used to soften plastic medical devices, was restricted in the EU Medical Devices Regulation (EU MDR 2017/745) and gradually replaced by alternative plasticizers. Neonates hospitalized in the neonatal intensive care unit (NICU) are vulnerable to toxic effects of plasticizers. From June 2020 to August 2022, urine samples (n = 1070) were repeatedly collected from premature neonates (n = 132, 4-10 samples per patient) born at <31 weeks gestational age and/or <1500 g birth weight in the Antwerp University Hospital, Belgium. Term control neonates (n = 21, 1 sample per patient) were included from the maternity ward. Phthalate and alternative plasticizers' metabolites were analyzed using liquid-chromatography coupled to tandem mass spectrometry. Phthalate metabolites were detected in almost all urine samples. Metabolites of alternative plasticizers, di-(2-ethylhexyl)-adipate (DEHA), di-(2-ethylhexyl)-terephthalate (DEHT) and cyclohexane-1,2-dicarboxylic-di-isononyl-ester (DINCH), had detection frequencies ranging 30-95 %. Urinary phthalate metabolite concentrations were significantly higher in premature compared to control neonates (p = 0.023). NICU exposure to respiratory support devices and blood products showed increased phthalate metabolite concentrations (p < 0.001). Phthalate exposure increased from birth until four weeks postnatally. The estimated phthalate intake exceeded animal-derived no-effect-levels (DNEL) in 10 % of samples, with maximum values reaching 24 times the DNEL. 29 % of premature neonates had at least once an estimated phthalate intake above the DNEL. Preterm neonates are still exposed to phthalates during NICU stay, despite the EU Medical Devices Regulation. NICU exposure to alternative plasticizers is increasing, though currently not regulated, with insufficient knowledge on their hazard profile.

Composition and release rates of chemicals in inkjet fabrics determined by non-targeted screening and targeted analysis

Unveiling composition and release rates of chemicals in chemical-intensive products (CIPs) such as inkjet fabrics that are applied extensively in advertising and publicizing industries, is of importance to sound management of chemicals. This study tentatively identified 212 compounds from 69 inkjet fabric samples using gas chromatograph coupled with quadrupole time-of-flight mass spectrometry (GC-QTOF-MS). Contents of six phthalate esters (PAEs) were quantified to range from 3.0 × 102 mg/kg to 3.1 × 105 mg/kg with GC-MS. Bis(2-ethylhexyl) phthalate was predominantly detected to average 96 g/kg. The inkjet fabrics collected from southern China contained fewer non-intentionally added substances (NIASs) than from northern China. Annual mass release rates (RM) of the 6 PAEs from inkjet fabrics to air were estimated to range from 1.4 × 10-2 kg/year to 2.8 × 104 kg/year in China in 2020, and the mean indoor RM was comparable with the outdoor one. Equilibrium partition coefficients of the compounds between the product and air, ambient temperature, and concentrations of chemicals in the product, are key factors leading to RM with the high variance. The findings indicate that contents of the NIASs in the CIPs should be minimized, and the refining concept should be adopted in design of the CIPs, so as to control the release of chemicals from the CIPs.

Safety Assessment of Trialkyl Trimellitates as Used in Cosmetics

The Expert Panel for Cosmetic Ingredient Safety (Panel) assessed the safety of 5 trialkyl trimellitates. These ingredients, which are all structurally related as alkyl esters of trimellitic acid, are reported to function in cosmetics as skin conditioning agents; 2 of the ingredients are also reported to function in cosmetics as plasticizers. The Panel reviewed the available data to determine the safety of these ingredients, and concluded that the trialkyl trimellitates are safe in the current practices of use and concentration when formulated to be non-irritating.

Hair as an alternative matrix to assess exposure of premature neonates to phthalate and alternative plasticizers in the neonatal intensive care unit

Due to adverse health effects, di-(2-ethylhexyl) phthalate (DEHP), a plasticizer used to soften plastic medical devices (PMDs), was restricted, and gradually replaced by alternative plasticizers (APs). Up to this date, urine was the sole matrix studied for plasticizer exposure in neonates hospitalized in the neonatal intensive care unit (NICU), a population highly vulnerable to toxic effects of plasticizers. The primary aim of this study was to assess simultaneous measurement of phthalate and AP metabolites in neonatal scalp hair. In addition, we aimed to use this matrix to investigate exposure of premature neonates to plasticizers during their stay in the NICU. Hair samples in this study were collected from premature neonates and their mothers included in a prospective birth cohort study in a tertiary NICU at the Antwerp University Hospital (UZA), Belgium. Samples from premature neonates (n = 45) and their mothers (n = 107) as well as from control neonates (n = 24) and mothers (n = 29) were analyzed using liquid-chromatography coupled to tandem mass spectrometry. This is the first study reporting metabolites of phthalate and alternative plasticizers in neonatal hair samples as biomarkers for exposure to these plasticizers. Results showed that hair sampled from premature neonates after a NICU stay contained significantly higher metabolite concentrations of both phthalates (DEHP, DiBP, and DnBP; 9.0-2500, 9.3-2200, and 24.7-5300 ng/g), and alternative plasticizers (DEHA, DEHT, and TOTM; 38.8-3400, 127.5-5700, and 10.8-8700 ng/g) - when compared to healthy control neonates. Besides, DEHP and DEHT metabolite concentrations were significantly higher than in hair sampled from adult populations. In addition, prolonged NICU exposure to non-invasive respiratory support devices and gastric tubes was correlated with increased concentrations in hair samples, indicating accumulation of plasticizers in this alternative matrix. In conclusion, our data indicate that preterm neonates are still highly exposed to phthalate and alternative plasticizers during NICU stay, despite the EU Medical Devices Regulation.

Phthalate exposure in the neonatal intensive care unit is associated with development of bronchopulmonary dysplasia

OBJECTIVE

Bronchopulmonary dysplasia (BPD) is a serious yet common morbidity of preterm birth. Although prior work suggests a possible role for phthalate exposure in the development of BPD, no study has rigorously evaluated this. Our objective was to determine whether hospital-based phthalate exposure is associated with the development of BPD and to identify developmental windows sensitive to exposure.

STUDY DESIGN

This is a prospective multicenter cohort study of 360 preterm infants born at 23-33 weeks gestation participating in the Developmental Impact of NICU Exposures (DINE) cohort. 939 urine specimens collected during the NICU stay were analyzed for biomarkers of phthalate exposure by liquid chromatography with tandem mass spectrometry. The modified Shennan definition was used to diagnose bronchopulmonary dysplasia. Reverse distributed-lag modeling identified developmental windows sensitive to specific phthalate exposure, controlling for relevant covariates including sex and respiratory support.

RESULTS

Thirty-five percent of participants were diagnosed with BPD. Exposure to specific phthalate mixtures at susceptible points in preterm infant development are associated with later diagnosis of BPD in models adjusted for use of respiratory support. The weighted influence of specific phthalate metabolites in the mixtures varied by sex. Metabolites of di(2-ethylhexyl) phthalate, a phthalate previously linked to neonatal respiratory support equipment, drove this association, particularly among female infants, at 26- to 30-weeks post-menstrual age.

CONCLUSIONS

This is the largest and only multi-site study of NICU-based phthalate exposure and clinical impact yet reported. In well-constructed models accounting for infant sex and respiratory support, we found a significant positive association between ultimate diagnosis of BPD and prior exposure to phthalate mixtures with DEHP predominance at 26- to 30-weeks PMA or 34-36-weeks PMA. This information is critically important as it identifies a previously unrecognized and modifiable contributing factor to BPD.

Comparison of Mechanical Properties of Three Tissue Conditioners: An Evaluation In Vitro Study

Introduction: Tissue conditioners have been widely used in various clinical applications in dentistry, such as treating inflamed alveolar ridges, temporarily relining partial and complete dentures, and the acquisition of functional impressions for denture fabrication. This study aimed to investigate the mechanical properties of the most prevalent tissue conditioner materials on the market, including Tissue Conditioners (TC), Visco Gel (VG), and FITT (F). Materials and Methods: The three tissue conditioners, TC, VG, and F, were assessed based on the parameters mentioned above. The following tests were performed based on the ISO 10139-1 and ISO 10139-2 requirements: Shore A hardness, denture plate adhesion, sorption, water solubility, and contraction after 1 and 3 days in water. Additional tests are described in the literature, such as ethanol content and gelling time. The tests were carried out by storing the materials in water at 37 °C for 7 days. Results: The gel times of all tested materials exceeded 5 min (TC = 300 [s], VG = 350 [s]). In vitro, phthalate-free materials exhibited higher dissolution in water after 14 days (VG = -260.78 ± 11.31 µg/mm2) compared to F (-76.12 ± 7.11 µg/mm2) and experienced faster hardening when stored in distilled water (F = 33.4 ± 0.30 Sh. A, VG = 59.2 ± 0.60 Sh. A). They also showed greater contractions. The connection of all materials to the prosthesis plate was consistent at 0.11 MPa. The highest counterbalance after 3 days was observed in TC = 3.53 ± 1.12%. Conclusions: Materials containing plasticizers that are not phthalates have worse mechanical properties than products containing these substances. Since phthalates are not allowed to be used indefinitely in medical devices, additional research is necessary, especially in vivo, to develop safe materials with superior functional properties to newer-generation alternatives. In vitro results often do not agree fully with those of in vivo outcomes.

Prevalence and Clinical Implications of Heightened Plastic Chemical Exposure in Pediatric Patients Undergoing Cardiopulmonary Bypass

Importance

Phthalate chemicals are used to manufacture disposable plastic medical products, including blood storage bags and components of cardiopulmonary bypass (CPB) circuits. During cardiac surgery, patients can be inadvertently exposed to phthalate chemicals that are released from these plastic products.

Objective

To quantify iatrogenic phthalate chemical exposure in pediatric patients undergoing cardiac surgery, and examine the link between phthalate exposure and post-operative outcomes.

Design Setting and Participants

The study cohort included 122 pediatric patients undergoing cardiac surgery at Children's National Hospital. For each patient, a single plasma sample was collected pre-operatively and two additional samples were collected post-operatively upon return from the operating room (post-operative day 0) and the morning after surgery (post-operative day 1).

Exposures

Concentrations of di(2-ethylhexyl)phthalate (DEHP) and its metabolites were quantified using ultra high-pressure liquid chromatography coupled to mass spectrometry.

Main Outcomes and Measures

Plasma concentrations of phthalates, post-operative blood gas measurements, and post-operative complications.

Results

Study subjects were subdivided into three groups, according to surgical procedure: 1) cardiac surgery not requiring CPB support, 2) cardiac surgery requiring CPB with crystalloid prime, and 3) cardiac surgery requiring CPB with red blood cells (RBCs) to prime the circuit. Phthalate metabolites were detected in all patients, and postoperative phthalate levels were highest in patients undergoing CPB with RBC-based prime. Age-matched (<1 year) CPB patients with elevated phthalate exposure were more likely to experience post-operative complications, including arrhythmias, low cardiac output syndrome, and additional post-operative interventions. RBC washing was an effective strategy to reduce DEHP levels in CPB prime.

Conclusions and Relevance

Pediatric cardiac surgery patients are exposed to phthalate chemicals from plastic medical products, and the degree of exposure increases in the context of CPB with RBC-based prime. Additional studies are warranted to measure the direct effect of phthalates on patient health outcomes and investigate mitigation strategies to reduce exposure.

Key Points

Question: Is cardiac surgery with cardiopulmonary bypass a significant source of phthalate chemical exposure in pediatric patients?Findings: In this study of 122 pediatric cardiac surgery patients, phthalate metabolites were quantified from blood samples before and after surgery. Phthalate concentrations were highest in patients undergoing cardiopulmonary bypass with red blood cell-based prime. Heightened phthalate exposure was associated with post-operative complications.Meaning: Cardiopulmonary bypass is a significant source of phthalate chemical exposure, and patients with heightened exposure may be at greater risk for postoperative cardiovascular complications.

Cytotoxic and genotoxic effects of leaking chemicals from serum infusion sets: an in-vitro study

Safety concerns about medical devices playing important role in health sciences and bioengineering research are rising day by day. Although there are specific standards regarding disposable medical materials, the information is updating with the toxicological studies. In this study, cytotoxic/genotoxic effects of chemicals leaking from serum infusion sets that have an important place in the clinic were investigated. Media containing leakage chemicals were prepared from equal samples taken from the plastic line sections of 13 different brands of serum infusion sets containing phthalates and the effects on the cultured cells were compared with the untreated control groups. To obtain leaking chemicals, extracting period was selected as 72 h, a routine set-change time in the clinic as indicated in various publications. Neutral red uptake and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tests were performed in L929 cells to determine cytotoxicity, and cytokinesis blocked micronucleus technique was performed in lymphocytes to determine genotoxicity. Cytotoxic and genotoxic damage levels were compared by evaluating cell-viability rates relative to control, micronucleus frequency, and nuclear division index values. The results showed that all sets caused a decrease in cell viability revealing the effects both on lysosomal and mitochondrial activity and increase in micronucleus frequencies in general. The number of similar studies is extremely limited, and in this study in addition to the short-term effects of using the serum infusion sets, the information about the sample tests to determine the biosecurity of disposable medical materials is given.

The Minderoo-Monaco Commission on Plastics and Human Health

Background

Plastics have conveyed great benefits to humanity and made possible some of the most significant advances of modern civilization in fields as diverse as medicine, electronics, aerospace, construction, food packaging, and sports. It is now clear, however, that plastics are also responsible for significant harms to human health, the economy, and the earth's environment. These harms occur at every stage of the plastic life cycle, from extraction of the coal, oil, and gas that are its main feedstocks through to ultimate disposal into the environment. The extent of these harms not been systematically assessed, their magnitude not fully quantified, and their economic costs not comprehensively counted.

Goals

The goals of this Minderoo-Monaco Commission on Plastics and Human Health are to comprehensively examine plastics' impacts across their life cycle on: (1) human health and well-being; (2) the global environment, especially the ocean; (3) the economy; and (4) vulnerable populations-the poor, minorities, and the world's children. On the basis of this examination, the Commission offers science-based recommendations designed to support development of a Global Plastics Treaty, protect human health, and save lives.

Report Structure

This Commission report contains seven Sections. Following an Introduction, Section 2 presents a narrative review of the processes involved in plastic production, use, and disposal and notes the hazards to human health and the environment associated with each of these stages. Section 3 describes plastics' impacts on the ocean and notes the potential for plastic in the ocean to enter the marine food web and result in human exposure. Section 4 details plastics' impacts on human health. Section 5 presents a first-order estimate of plastics' health-related economic costs. Section 6 examines the intersection between plastic, social inequity, and environmental injustice. Section 7 presents the Commission's findings and recommendations.

Plastics

Plastics are complex, highly heterogeneous, synthetic chemical materials. Over 98% of plastics are produced from fossil carbon- coal, oil and gas. Plastics are comprised of a carbon-based polymer backbone and thousands of additional chemicals that are incorporated into polymers to convey specific properties such as color, flexibility, stability, water repellence, flame retardation, and ultraviolet resistance. Many of these added chemicals are highly toxic. They include carcinogens, neurotoxicants and endocrine disruptors such as phthalates, bisphenols, per- and poly-fluoroalkyl substances (PFAS), brominated flame retardants, and organophosphate flame retardants. They are integral components of plastic and are responsible for many of plastics' harms to human health and the environment.Global plastic production has increased almost exponentially since World War II, and in this time more than 8,300 megatons (Mt) of plastic have been manufactured. Annual production volume has grown from under 2 Mt in 1950 to 460 Mt in 2019, a 230-fold increase, and is on track to triple by 2060. More than half of all plastic ever made has been produced since 2002. Single-use plastics account for 35-40% of current plastic production and represent the most rapidly growing segment of plastic manufacture.Explosive recent growth in plastics production reflects a deliberate pivot by the integrated multinational fossil-carbon corporations that produce coal, oil and gas and that also manufacture plastics. These corporations are reducing their production of fossil fuels and increasing plastics manufacture. The two principal factors responsible for this pivot are decreasing global demand for carbon-based fuels due to increases in 'green' energy, and massive expansion of oil and gas production due to fracking.Plastic manufacture is energy-intensive and contributes significantly to climate change. At present, plastic production is responsible for an estimated 3.7% of global greenhouse gas emissions, more than the contribution of Brazil. This fraction is projected to increase to 4.5% by 2060 if current trends continue unchecked.

Plastic Life Cycle

The plastic life cycle has three phases: production, use, and disposal. In production, carbon feedstocks-coal, gas, and oil-are transformed through energy-intensive, catalytic processes into a vast array of products. Plastic use occurs in every aspect of modern life and results in widespread human exposure to the chemicals contained in plastic. Single-use plastics constitute the largest portion of current use, followed by synthetic fibers and construction.Plastic disposal is highly inefficient, with recovery and recycling rates below 10% globally. The result is that an estimated 22 Mt of plastic waste enters the environment each year, much of it single-use plastic and are added to the more than 6 gigatons of plastic waste that have accumulated since 1950. Strategies for disposal of plastic waste include controlled and uncontrolled landfilling, open burning, thermal conversion, and export. Vast quantities of plastic waste are exported each year from high-income to low-income countries, where it accumulates in landfills, pollutes air and water, degrades vital ecosystems, befouls beaches and estuaries, and harms human health-environmental injustice on a global scale. Plastic-laden e-waste is particularly problematic.

Environmental Findings

Plastics and plastic-associated chemicals are responsible for widespread pollution. They contaminate aquatic (marine and freshwater), terrestrial, and atmospheric environments globally. The ocean is the ultimate destination for much plastic, and plastics are found throughout the ocean, including coastal regions, the sea surface, the deep sea, and polar sea ice. Many plastics appear to resist breakdown in the ocean and could persist in the global environment for decades. Macro- and micro-plastic particles have been identified in hundreds of marine species in all major taxa, including species consumed by humans. Trophic transfer of microplastic particles and the chemicals within them has been demonstrated. Although microplastic particles themselves (>10 µm) appear not to undergo biomagnification, hydrophobic plastic-associated chemicals bioaccumulate in marine animals and biomagnify in marine food webs. The amounts and fates of smaller microplastic and nanoplastic particles (MNPs <10 µm) in aquatic environments are poorly understood, but the potential for harm is worrying given their mobility in biological systems. Adverse environmental impacts of plastic pollution occur at multiple levels from molecular and biochemical to population and ecosystem. MNP contamination of seafood results in direct, though not well quantified, human exposure to plastics and plastic-associated chemicals. Marine plastic pollution endangers the ocean ecosystems upon which all humanity depends for food, oxygen, livelihood, and well-being.

Human Health Findings

Coal miners, oil workers and gas field workers who extract fossil carbon feedstocks for plastic production suffer increased mortality from traumatic injury, coal workers' pneumoconiosis, silicosis, cardiovascular disease, chronic obstructive pulmonary disease, and lung cancer. Plastic production workers are at increased risk of leukemia, lymphoma, hepatic angiosarcoma, brain cancer, breast cancer, mesothelioma, neurotoxic injury, and decreased fertility. Workers producing plastic textiles die of bladder cancer, lung cancer, mesothelioma, and interstitial lung disease at increased rates. Plastic recycling workers have increased rates of cardiovascular disease, toxic metal poisoning, neuropathy, and lung cancer. Residents of "fenceline" communities adjacent to plastic production and waste disposal sites experience increased risks of premature birth, low birth weight, asthma, childhood leukemia, cardiovascular disease, chronic obstructive pulmonary disease, and lung cancer.During use and also in disposal, plastics release toxic chemicals including additives and residual monomers into the environment and into people. National biomonitoring surveys in the USA document population-wide exposures to these chemicals. Plastic additives disrupt endocrine function and increase risk for premature births, neurodevelopmental disorders, male reproductive birth defects, infertility, obesity, cardiovascular disease, renal disease, and cancers. Chemical-laden MNPs formed through the environmental degradation of plastic waste can enter living organisms, including humans. Emerging, albeit still incomplete evidence indicates that MNPs may cause toxicity due to their physical and toxicological effects as well as by acting as vectors that transport toxic chemicals and bacterial pathogens into tissues and cells.Infants in the womb and young children are two populations at particularly high risk of plastic-related health effects. Because of the exquisite sensitivity of early development to hazardous chemicals and children's unique patterns of exposure, plastic-associated exposures are linked to increased risks of prematurity, stillbirth, low birth weight, birth defects of the reproductive organs, neurodevelopmental impairment, impaired lung growth, and childhood cancer. Early-life exposures to plastic-associated chemicals also increase the risk of multiple non-communicable diseases later in life.

Economic Findings

Plastic's harms to human health result in significant economic costs. We estimate that in 2015 the health-related costs of plastic production exceeded $250 billion (2015 Int$) globally, and that in the USA alone the health costs of disease and disability caused by the plastic-associated chemicals PBDE, BPA and DEHP exceeded $920 billion (2015 Int$). Plastic production results in greenhouse gas (GHG) emissions equivalent to 1.96 gigatons of carbon dioxide (CO2e) annually. Using the US Environmental Protection Agency's (EPA) social cost of carbon metric, we estimate the annual costs of these GHG emissions to be $341 billion (2015 Int$).These costs, large as they are, almost certainly underestimate the full economic losses resulting from plastics' negative impacts on human health and the global environment. All of plastics' economic costs-and also its social costs-are externalized by the petrochemical and plastic manufacturing industry and are borne by citizens, taxpayers, and governments in countries around the world without compensation.

Social Justice Findings

The adverse effects of plastics and plastic pollution on human health, the economy and the environment are not evenly distributed. They disproportionately affect poor, disempowered, and marginalized populations such as workers, racial and ethnic minorities, "fenceline" communities, Indigenous groups, women, and children, all of whom had little to do with creating the current plastics crisis and lack the political influence or the resources to address it. Plastics' harmful impacts across its life cycle are most keenly felt in the Global South, in small island states, and in disenfranchised areas in the Global North. Social and environmental justice (SEJ) principles require reversal of these inequitable burdens to ensure that no group bears a disproportionate share of plastics' negative impacts and that those who benefit economically from plastic bear their fair share of its currently externalized costs.

Conclusions

It is now clear that current patterns of plastic production, use, and disposal are not sustainable and are responsible for significant harms to human health, the environment, and the economy as well as for deep societal injustices.The main driver of these worsening harms is an almost exponential and still accelerating increase in global plastic production. Plastics' harms are further magnified by low rates of recovery and recycling and by the long persistence of plastic waste in the environment.The thousands of chemicals in plastics-monomers, additives, processing agents, and non-intentionally added substances-include amongst their number known human carcinogens, endocrine disruptors, neurotoxicants, and persistent organic pollutants. These chemicals are responsible for many of plastics' known harms to human and planetary health. The chemicals leach out of plastics, enter the environment, cause pollution, and result in human exposure and disease. All efforts to reduce plastics' hazards must address the hazards of plastic-associated chemicals.

Recommendations

To protect human and planetary health, especially the health of vulnerable and at-risk populations, and put the world on track to end plastic pollution by 2040, this Commission supports urgent adoption by the world's nations of a strong and comprehensive Global Plastics Treaty in accord with the mandate set forth in the March 2022 resolution of the United Nations Environment Assembly (UNEA).International measures such as a Global Plastics Treaty are needed to curb plastic production and pollution, because the harms to human health and the environment caused by plastics, plastic-associated chemicals and plastic waste transcend national boundaries, are planetary in their scale, and have disproportionate impacts on the health and well-being of people in the world's poorest nations. Effective implementation of the Global Plastics Treaty will require that international action be coordinated and complemented by interventions at the national, regional, and local levels.This Commission urges that a cap on global plastic production with targets, timetables, and national contributions be a central provision of the Global Plastics Treaty. We recommend inclusion of the following additional provisions:The Treaty needs to extend beyond microplastics and marine litter to include all of the many thousands of chemicals incorporated into plastics.The Treaty needs to include a provision banning or severely restricting manufacture and use of unnecessary, avoidable, and problematic plastic items, especially single-use items such as manufactured plastic microbeads.The Treaty needs to include requirements on extended producer responsibility (EPR) that make fossil carbon producers, plastic producers, and the manufacturers of plastic products legally and financially responsible for the safety and end-of-life management of all the materials they produce and sell.The Treaty needs to mandate reductions in the chemical complexity of plastic products; health-protective standards for plastics and plastic additives; a requirement for use of sustainable non-toxic materials; full disclosure of all components; and traceability of components. International cooperation will be essential to implementing and enforcing these standards.The Treaty needs to include SEJ remedies at each stage of the plastic life cycle designed to fill gaps in community knowledge and advance both distributional and procedural equity.This Commission encourages inclusion in the Global Plastic Treaty of a provision calling for exploration of listing at least some plastic polymers as persistent organic pollutants (POPs) under the Stockholm Convention.This Commission encourages a strong interface between the Global Plastics Treaty and the Basel and London Conventions to enhance management of hazardous plastic waste and slow current massive exports of plastic waste into the world's least-developed countries.This Commission recommends the creation of a Permanent Science Policy Advisory Body to guide the Treaty's implementation. The main priorities of this Body would be to guide Member States and other stakeholders in evaluating which solutions are most effective in reducing plastic consumption, enhancing plastic waste recovery and recycling, and curbing the generation of plastic waste. This Body could also assess trade-offs among these solutions and evaluate safer alternatives to current plastics. It could monitor the transnational export of plastic waste. It could coordinate robust oceanic-, land-, and air-based MNP monitoring programs.This Commission recommends urgent investment by national governments in research into solutions to the global plastic crisis. This research will need to determine which solutions are most effective and cost-effective in the context of particular countries and assess the risks and benefits of proposed solutions. Oceanographic and environmental research is needed to better measure concentrations and impacts of plastics <10 µm and understand their distribution and fate in the global environment. Biomedical research is needed to elucidate the human health impacts of plastics, especially MNPs.

Summary

This Commission finds that plastics are both a boon to humanity and a stealth threat to human and planetary health. Plastics convey enormous benefits, but current linear patterns of plastic production, use, and disposal that pay little attention to sustainable design or safe materials and a near absence of recovery, reuse, and recycling are responsible for grave harms to health, widespread environmental damage, great economic costs, and deep societal injustices. These harms are rapidly worsening.While there remain gaps in knowledge about plastics' harms and uncertainties about their full magnitude, the evidence available today demonstrates unequivocally that these impacts are great and that they will increase in severity in the absence of urgent and effective intervention at global scale. Manufacture and use of essential plastics may continue. However, reckless increases in plastic production, and especially increases in the manufacture of an ever-increasing array of unnecessary single-use plastic products, need to be curbed.Global intervention against the plastic crisis is needed now because the costs of failure to act will be immense.

Di-(2-ethylhexyl) Phthalate Limits the Lipid-Lowering Effects of Simvastatin by Promoting Protein Degradation of Low-Density Lipoprotein Receptor: Role of PPARγ-PCSK9 and LXRα-IDOL Signaling Pathways

Dialysis prevents death from uremia in patients with end-stage renal disease (ESRD). Nevertheless, during hemodialysis, circulating levels of di-(2-ethylhexyl) phthalate (DEHP) are increased due to phthalates leaching from medical tubes. Statins are an effective therapy for reducing the risks associated with cardiovascular diseases in patients with chronic kidney disease; however, the mechanism by which statins fail to reduce cardiovascular events in hemodialysis ESRD patients remains unclear. In this study, we investigated whether DEHP and its metabolites interfere with the lipid-lowering effect of statins in hepatocytes. In Huh7 cells, treatment with DEHP and its metabolites abolished the simvastatin-conferred lipid-lowering effect. Mechanistically, DEHP down-regulated the expression of low-density lipoprotein receptor (LDLR) and led to a decrease in LDL binding, which was mediated by the activation of the PPARγ-PCSK9 and LXRα-IDOL signaling pathways. Additionally, the NOX-ROS-TRPA1 pathway is involved in the DEHP-mediated inhibition of LDLR expression and LDL binding activity. Blockage of this pathway abrogated the DEHP-mediated inhibition in the LDLR expression and LDL binding of simvastatin. Collectively, DEHP induces the activation of the NOX-ROS-TRPA1 pathway, which in turn activates PPARγ-PCSK9- and LXRα-IDOL-dependent signaling, and, ultimately, diminishes the statin-mediated lipid-lowering effect in hepatocytes.

Phthalate derivative DEHP disturbs the antiproliferative effect of camptothecin in human lung cancer cells by attenuating DNA damage and activating Akt/NF-κB signaling pathway

Plasticizers/phthalates play a facilitating role in the development of cancer and help the tumor to grow and metastasize. Camptothecin (CPT) and its derivatives are known to have anticancer properties of inhibiting cell growth, promoting cell apoptosis, and increasing autophagy. Therefore, in this study, we investigated whether the presence of di(2-ethylhexyl) phthalate (DEHP) could hinder apoptosis and autophagy caused by CPT in non-small cell lung cancer (NSCLC) cells. We found that DEHP interferes with CPT-induced apoptosis and autophagy and increases the prosurvival pathway by reducing the DNA damage marker γ-H2AX and activating the Akt and NF-κB pathways. Furthermore, we also confirmed that combining DEHP with 3-MA has additive effects in inhibiting autophagy and apoptosis in NSCLC cells. Taken together, our findings show that DEHP could affect CPT-induced anticancer treatment and provide evidence to show that DEHP induces chemoresistance in CPT-based chemotherapy.

Neonatal exposure to phthalate and alternative plasticizers via parenteral nutrition

Di-(2-ethylhexyl) phthalate (DEHP), a plasticizer used to soften plastic medical devices (PMDs), was restricted in PMDs due to adverse health effects, being gradually replaced by alternative plasticizers (APs). Parenteral nutrition (PN), essential in the care for premature neonates in the neonatal intensive care unit, is stored in plastic storage bags and administered intravenously through plastic infusion circuits. We investigated to which extent PN contributes to current phthalate and AP exposure in premature neonates. First, we showed that DEHP and several APs are present in relevant amounts in PMDs used for neonatal PN administration. Secondly, ex vivo experiments mimicking clinical PN administration showed that lipid emulsions contained significant concentrations of DEHP and several APs (ATBC, TOTM, DEHT & DEHA), while hardly any plasticizers were detected in non-lipid solutions. ATBC leached from infusion circuits, while lipid emulsions were the major source for DEHP, TOTM, DEHT, and DEHA. PN administration resulted in estimated daily exposures of 13.9 µg/kg/d DEHP and 95.7 µg/kg/d ATBC in premature neonates, below their respective reference doses. Our data indicate that premature neonates requiring PN are still exposed to DEHP, as well as to a range of APs, making it a target for reduction of harmful plasticizer exposure.

Effects of time, temperature, and sebum layer on migration rate of plasticizers in polyvinyl chloride products

Large amounts of plasticizers, such as di(2-ethylhexyl) phthalate (DEHP) and dioctyl terephthalate (DOTP), are added to various polyvinyl chloride (PVC) products. To assess the human exposure to these plasticizers on using PVC products, it is important to know their migration rate. However, conventional migration tests conducted at a fixed time and temperature are often insufficient for determining possible variations in migration rates with respect to time, temperature, and sebum layer. In this study, the migration rates of DEHP and DOTP from five PVC products were measured using a polydimethylsiloxane (PDMS) sampler at different times and temperatures, in the presence and absence of artificial sebum. Although the migrated mass of the plasticizers increased over time, the average migration rate decreased. The average migration rates increased with increasing temperature and in the presence of an artificial sebum layer between the product and the PDMS sampler. When the artificial sebum layer was added, the average migration rate increased considerably by a factor of 1.5-14, suggesting that sebum should be considered to avoid the underestimation of dermal exposure to highly hydrophobic plasticizers, such as DEHP and DOTP. Based on the measured values, a conceptual analysis was conducted to quantitatively assess the difference in the migration rate of plasticizers caused by the difference between the time set for the migration test and the exposure time when the product is used. To reduce uncertainties and the potential underestimation of dermal exposure, an appropriate time for the experiment should be set to simulate the exposure scenario of a given product.

Simultaneous and sensitive determination of the main metabolites of the plasticizer DEHP and its substitutes DEHTP, DINCH and TEHTM in human urine by coupling of on-line SPE, UHPLC and tandem mass spectrometry

With the prominent but toxicologically critical plasticizer di-(2-ethylhexyl) phthalate (DEHP) declining, alternative plasticizers are increasingly used leading to a continuously more diverse exposure situation of humans with multiple plasticizers. Therefore, an on-line SPE-LC-MS/MS method for the simultaneous determination of the most relevant urinary biomarkers of exposure to DEHP and the alternative plasticizers 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH), di-(2-ethylhexyl) terephthalate (DEHTP) and tri-(2-ethylhexyl) trimellitate (TEHTM) was developed. The method is characterized by a high sensitivity with limits of detection ranging from 0.006 to 0.047 μg L^-1 combined with an easy and straightforward sample preparation procedure. The wide linear working range of the method enables a reliable determination of analyte background levels in the general population as well as its potential use for monitoring studies investigating elevated plasticizer exposure settings. The method was successfully applied to urine samples from ten volunteers without occupational exposure to plasticizers revealing ubiquitous background exposure levels of the common plasticizers DEHP, DEHTP and DINCH.

Occurrence of legacy and replacement plasticizers, bisphenols, and flame retardants in potable water in Montreal and South Africa

The occurrence of thirty-nine contaminants including plasticizers, bisphenols, and flame retardants in potable water from Montreal and South Africa was analyzed to determine their presence and concentrations in different water sources. In Montreal, five bottled water (BW) brands and three drinking water treatment plants (DWTP) were included. In South Africa, water was sampled from one urban DWTP located in Pretoria, Gauteng, and one rural DWTP located in Vhembe, along with water from the same rural DWTP which had been stored in small and large plastic containers. A combination of legacy compounds, typically with proven toxic effects, and replacement compounds was investigated. Bisphenols, Dechlorane-602, Dechlorane-603, and s-dechlorane plus (s-DP) were not detected in any water samples, and a-dechlorane plus (a-DP) was only detected in one sample from Pretoria at a concentration of 1.09 ng/L. Lower brominated polybrominated diphenyl ethers (PBDE)s were detected more frequently than higher brominated PBDEs, always at low concentrations of <2 ng/L, and total PBDE levels were statistically higher in South Africa than in Montreal. Replacement flame retardants, organophosphate esters (OPEs), were detected at statistically higher concentrations in Montreal's BW (68.56 ng/L), drinking water (DW) (421.45 ng/L) and Vhembe (198.33 ng/L) than legacy PBDEs. Total OPE concentrations did not demonstrate any geographical trend; however, levels were statistically higher in Montreal's DW than Montreal's BW. Plasticizers were frequently detected in all samples, with legacy compounds DEHP, DBP, and replacement DINCH being detected in 100 % of samples with average concentrations ranging from 6.89 ng/L for DEHP in Pretoria to 175.04 ng/L for DINCH in Montreal's DW. Total plasticizer concentrations were higher in Montreal than in South Africa. The replacement plasticizers (DINCH, DINP, DIDA, and DEHA) were detected at similar frequencies and concentrations as legacy plasticizers (DEHP, DEP, DBP, MEHP). For the compounds reported in earlier studies, the concentrations detected in the present study were similar to other locations. These compounds are not currently regulated in drinking water but their frequent detection, especially OPEs and plasticizers, and the presence of replacement compounds at similar or higher levels than their legacy compounds demonstrate the importance of further investigating the prevalence and the ecological or human health effects of these compounds.

Study on the Physical, Thermal and Mechanical Properties of SEBS/PP (Styrene-Ethylene-Butylene-Styrene/Polypropylene) Blend as a Medical Fluid Bag

The presence of DEHP in PVC-based medical bags poses a significant health risk to patients undergoing blood transfusion. In order to fabricate safer medical fluid bag materials, the use of SEBS/PP polymer blend as a potential material was investigated. Polymeric blends with varying weight percentages of styrene-ethylene-butylene-styrene/polypropylene (SEBS/PP) were fabricated by melt mixing using an internal Haake mixer. The physical properties of the SEBS/PP polymer blends were investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), and inductively coupled plasma–mass spectrometry (ICP-MS). In addition, measurements of the mechanical strength (tensile strength and Young’s modulus) as per ASTM 638, polymer hardness was tested using a durometer and swelling was analysed through water absorption and compared with commercial PVC-based blood bags. The results indicate that the SEBS/PP 50/50 blend has approximately similar characteristics as PVC-based blood bags. The SEBS/PP polymer blend possesses approximate tensile strength and Young’s modulus with values of 23.28 MPa and 14.42 MPa, respectively, to that of the conventional PVC blood bags. The results show that the SEBS/PP polymer blends have negligible zinc and aluminium migration with values of 1.6 and 2.1 mg/kg, respectively, and do not elute any harmful leachates, while the thermal studies indicate that the studied SEBS/PP materials are capable of withstanding steam sterilisation at 120 °C and cold storage below −40 °C. The investigated material can be utilized for medical fluid bags and contributes towards sustainable development goals, such as SDG 3 to ensure healthy lives and promote well-being, as well as SDG 12 to ensure sustainable consumption and production patterns.

Coupled Dynamic Material Flow, Multimedia Environmental Model, and Ecological Risk Analysis for Chemical Management: A Di(2-ethylhexhyl) Phthalate Case in China

Di(2-ethylhexhyl) phthalate (DEHP) is a widely used plasticizer that has adverse effects on ecosystems and human health. However, data about its stocks, flows, emission rates, as well as ecological risks are generally unknown in China, one of the world's largest producers of chemicals including DEHP, limiting sound management of chemicals. Herein, dynamic material flow analysis, coupled with a multimedia environmental model and ecological risk analysis, was performed to fill the data gap about DEHP in China mainland from 1956 to 2020. Results indicate that the in-use stocks of DEHP increased from 6.54 × 10⁶ kg in 1956 to 8.40 × 10⁹ kg in 2020. With growth in the emission rates, DEHP concentrations in air, soil, water, and sediment kept increasing from 1956 to 2010, which declined after 2010 and regrew after 2015. Sediment was a main sink of DEHP with the highest ecological risk quotient of >10 after 1999, necessitating measures for controlling the risk, for example, technology innovation to reduce DEHP emission rates, and substitution of DEHP with low-toxic alternatives. The coupled models that connect socio-economic data with ecological risk output may provide a systematic methodology for verification of the data necessary for risk control of chemicals.

Di-(2-ethylhexyl) phthalate substitutes accelerate human adipogenesis through PPARγ activation and cause oxidative stress and impaired metabolic homeostasis in mature adipocytes

The obesity pandemic is presumed to be accelerated by endocrine disruptors such as phthalate-plasticizers, which interfere with adipose tissue function. With the restriction of the plasticizer di-(2-ethylhexyl)-phthalate (DEHP), the search for safe substitutes gained importance. Focusing on the master regulator of adipogenesis and adipose tissue functionality, the peroxisome proliferator-activated receptor gamma (PPARγ), we evaluated 20 alternative plasticizers as well as their metabolites for binding to and activation of PPARγ and assessed effects on adipocyte lipid accumulation. Among several compounds that showed interaction with PPARγ, the metabolites MINCH, MHINP, and OH-MPHP of the plasticizers DINCH, DINP, and DPHP exerted the highest adipogenic potential in human adipocytes. These metabolites and their parent plasticizers were further analyzed in human preadipocytes and mature adipocytes using cellular assays and global proteomics. In preadipocytes, the plasticizer metabolites significantly increased lipid accumulation, enhanced leptin and adipsin secretion, and upregulated adipogenesis-associated markers and pathways, in a similar pattern to the PPARγ agonist rosiglitazone. Proteomics of mature adipocytes revealed that both, the plasticizers and their metabolites, induced oxidative stress, disturbed lipid storage, impaired metabolic homeostasis, and led to proinflammatory and insulin resistance promoting adipokine secretion. In conclusion, the plasticizer metabolites enhanced preadipocyte differentiation, at least partly mediated by PPARγ activation and, together with their parent plasticizers, affected the functionality of mature adipocytes similar to reported effects of a high-fat diet. This highlights the need to further investigate the currently used plasticizer alternatives for potential associations with obesity and the metabolic syndrome.

In vitro and in silico approach to study the hormonal activities of the alternative plasticizer tri-(2-ethylhexyl) trimellitate TEHTM and its metabolites

Tri-(2-ethylhexyl) trimellitate (TEHTM) is a plasticizer for polyvinyl chloride (PVC) material used in medical devices. It is an alternative to di-(2-ethylhexyl) phthalate (DEHP), a well-known reprotoxic and endocrine disruptor. As plasticizers are known to easily migrate when in contact with fatty biological fluids, patient exposure to TEHTM is highly probable. However, there is currently no data on the potential endocrine-disrupting effects of its human metabolites. To evaluate the effects of TEHTM metabolites on endocrine activity, they were first synthesized and their effects on estrogen, androgen and thyroid receptors, as well as steroid synthesis, were investigated by combining in vitro and in silico approaches. Among the primary metabolites, only 4-MEHTM (4-mono-(2-ethylhexyl) trimellitate) showed agonist activities on ERs and TRs, while three diesters were TR antagonists at non-cytotoxic concentrations. These results were completed by docking experiments which specified the ER and TR isoforms involved. A mixture of 2/1-MEHTM significantly increased the estradiol level and reduced the testosterone level in H295R cell culture supernatants. The oxidized secondary metabolites of TEHTM had no effect on ER, AR, TR receptors or on steroid hormone synthesis. Among the fourteen metabolites, these data showed that two of them (4-MEHTM and 2/1-MEHTM) induced effect on hormonal activities in vitro. However, by comparing the concentrations of the primary metabolites found in human urine with the active concentrations determined in bioassays, it can be suggested that the metabolites will not be active with regard to estrogen, androgen, thyroid receptors and steroidogenesis-mediated effects.

Application of a Liquid-Liquid Microextraction Method Based on a Natural Hydrophobic Deep Eutectic Solvent for the Extraction of Plastic Migrants from Kombuchas

A vortex-assisted liquid-liquid microextraction, based on a natural hydrophobic deep eutectic solvent made from the monoterpene thymol and octanoic fatty acid, was employed for the analysis of 11 phthalate esters and one adipate in kombucha (a tea-based fermented beverage). Separation and determination were performed using an ultra-high performance liquid chromatography (UHPLC) system coupled to a single quadrupole mass spectrometer. Confirmatory analyses were carried out through UHPLC tandem mass spectrometry. The full method was validated in terms of matrix effect, matrix-matched calibration, sensitivity, recovery, limits of detection and quantification and repeatability. Satisfactory determination coefficients for quadratic calibration curves (≥0.9938), recovery values (67–120%) and limits of detection (0.07–5.45 µg/L) were obtained. Analysis of 26 kombucha samples reported concentrations for dibutyl phthalate and dimethyl phthalate in the range between the limit of quantification (LOQ) and 16.18 ± 1.14 µg/L, although these phthalates were also detected under the LOQ in some of the analyzed samples. Only one of the samples bottled in plastic containers (7) did not present residues while only five of the 19 samples in glass bottles contained any plasticizer. However, the highest concentration was found in a kombucha bottled in food-grade glass. This work represents the first application in which phthalates and adipates are analyzed in kombuchas.

Legacy and alternative plasticizers in surface sediment of black-odorous urban rivers across China: Occurrence, spatial distribution, and ecological risk assessment

In this study, surface sediment samples from 173 black-odorous urban rivers in 74 cities of China were investigated regarding the occurrence, spatial distribution, and ecological risk of legacy phthalates (LPs) and alternative plasticizers (APs). The total concentrations of Σ₇LPs and Σ₆APs ranged from 0.0035 to 522 μg/g dw (median: 33 μg/g dw; mean: 60 μg/g dw) and from 0.0015 to 16 μg/g dw (median: 16 μg/g dw; mean: 2.2 μg/g dw), respectively. Di(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DnBP), and di-iso-butyl phthalate (DiBP) were the dominant LPs, and di-iso-decyl phthalate and di-iso-nonylcyclohexane-1,2-dicarboxylate were the dominant APs. The concentrations and compositions of the LPs and APs varied among different sites and regions, implying location-specific use or production of LPs and APs. The pollutant concentrations in southern and central China were higher than those in northern China. Among the seven regions, Northwest China had the lowest concentrations of LPs and APs. This could be related to industry development level, municipal facilities, and population density. Total organic carbon (TOC) was significantly and positively correlated with the pollutant concentrations, implying that TOC could be an important influencing factor for the distribution of LPs and APs in sediments. The risk quotients of DiBP and DnBP in almost all sediment samples were above 1, indicating the high ecological risks to aquatic organisms. Nevertheless, DEHP, di-methyl phthalate, di-ethyl phthalate, and di-n-octyl phthalate showed low or moderate ecological risks for most sampling sites.

Phthalate Exposures in the Neonatal Intensive Care Unit

Background: Di-2-ethylhexyl phthalate (DEHP), a phthalate compound found in medical devices, may cause toxic effects in premature infants. In this study, the objective is to quantify DEHP exposures from various intravenous and respiratory therapy devices, and to use these values to predict typical exposure for an infant in a neonatal unit. Methods: Common IV products used on infants are directed through various types of IV tubing (IVT) and analyzed for DEHP content. DEHP exposure for infants receiving respiratory therapy was determined indirectly through analysis of urine DEHP metabolites. By deriving these values for DEHP we calculated the daily exposure to DEHP from common IV fluids (IVF) and respiratory devices during hospitalization in a neonatal unit. Results: IVF labeled DEHP-positive showed very high concentrations of DEHP, but when passed through IVT, substantial amounts were adsorbed. DEHP was undetectable with all DEHP-negative IVF tests, except when passed through DEHP-positive IVT. The DEHP leached from most respiratory devices was relatively modest, except that detected from bubble CPAP. In 14 very low birthweight infants, the mean DEHP exposure was 182,369 mcg/kg over 81.2 days of the initial hospitalization. Ninety-eight percent of the exposure was from respiratory devices, with bubble CPAP accounting for 95% of the total DEHP exposure in these infants. Conclusions: The DEHP exposure in our neonatal unit can be reduced markedly by avoiding or modifying bubble CPAP equipment and avoiding IV tubing containing DEHP.

Recent developments in etiology and disease modeling of biliary atresia: a narrative review

Biliary atresia (BA) is a rare but severe fibroinflammatory disease of the extrahepatic and the intrahepatic bile ducts. Without prompt interventions, BA has fatal outcomes and is the most common indicator for pediatric liver transplantation (LTx). While the mainstay of treatment involves surgically correcting the extrahepatic biliary obstruction via Kasai hepato-portoenterostomy (KHPE), activation of a multitude of biological pathways and yet-to-be-determined etiology in BA continue to foster liver inflammation, cirrhosis and need for LTx. However, important caveats still exist in our understandings of the biliary pathophysiology, the rapidity of liver fibrosis and progression to liver failure, largely due to limited knowledge of the triggers of biliary injury and the inability to accurately model human BA. Although inconclusive, a large body of existing literature points to a potential viral infection in the early peri- or postnatal period as triggers of epithelial injury that perpetuates the downstream biliary disease. Further confounding this issue, are the lack of in-vivo and in-vitro models to efficiently recapitulate the cardinal features of BA, primarily liver fibrosis. To overcome these barriers in BA research, new directions in recent years have enabled (I) identification of additional triggers of biliary injury linked mostly to environmental toxins, (II) development of models to investigate liver fibrogenesis, and (III) translational research using patient-derived organoids. Here, we discuss recent advances that undoubtedly will stimulate future efforts investigating these new and exciting avenues towards mechanistic and drug discovery efforts and disease-preventive measures. The implications of these emerging scientific investigations and disease modeling in severe fibrosing cholangiopathies like BA are enormous and contribute substantially in our understandings of this rare but deadly disease. These findings are also expected to facilitate expeditious identification of translationally targetable pathways and bring us one step closer in treating an infant with BA, a population highly vulnerable to life-long liver related complications.

Phthalate Plasticizers in Children's Products and Estimation of Exposure: Importance of Migration Rate

Plasticizers are added to diverse consumer products including children's products. Owing to their potential for endocrine disruption, the use of phthalate plasticizers is restricted in many children's products. In this study, exposure to five phthalate esters (dibutylphthalate, di(2-ethylhexyl) phthalate (DEHP), diethyl phthalate, di-isobutyl phthalate, and diisononyl phthalate (DINP)) and an alternative (di-ethylhexyl adipate) was assessed by the use of children's products based on chemical analysis of 3345 products purchased during 2017 and 2019 in Korea. Plasticizers were found above the detection limits in 387 products, and DEHP and DINP were the two most predominantly detected plasticizers. Deterministic and probabilistic estimation of the margin of exposure at a screening level revealed that the use of children's products might be an important risk factor. However, it is also highly likely that the exposure could be overestimated, because the migration rate was estimated based solely on the content of plasticizers in children's products. Chemical migration is a key process determining the absorption of plasticizers from products; thus, further refinements in experimental determination or model estimation of the migration rate are required.

Plasticizer exposure of infants during cardiac surgery

In the present study we investigated the internal exposure situation of infant patients to the plasticizers TEHTM (tri-2-ethylhexyl trimellitate) and DEHP (di-2-ethylhexyl phthalate). The study collective included 21 infant patients aged 2-22 months that had to undergo cardiac surgery using cardio pulmonary bypass (CPB). Each patient, but one, received blood products during surgery. A special feature was that the used CPB tubings were exclusively plasticized with the alternative plasticizer TEHTM and were free of the standard plasticizer DEHP, that raises increasing toxicological concern. The blood products were stored in DEHP plasticized blood bags. Blood and urine samples of each infant patient were analysed before and after the surgery for the levels of the plasticizers DEHP and TEHTM and their metabolites. In general, the plasticizers were detected in the post-surgery blood samples only, with TEHTM in low levels (median 18.4 μg/L) and DEHP in rather elevated levels (median 1046 μg/L). With respect to the urine samples, TEHTM metabolites were not detected in any of the samples. DEHP metabolites were found in all urine samples, however, in significantly increased median levels in the post-surgery urine samples of the infants (increase factor 5-26). Thus, the present study clearly demonstrates the strong contribution of standard medical procedures to the internal plasticizer burden of patients. Particularly with regard to the suspected endocrine disrupting activities of the phthalate plasticizer DEHP, the elevated internal levels of this plasticizer and its metabolites in infants following cardiac surgery are alarming.

Plasticizer Degradation by Marine Bacterial Isolates: A Proteogenomic and Metabolomic Characterization

Many commercial plasticizers are toxic endocrine-disrupting chemicals that are added to plastics during manufacturing and may leach out once they reach the environment. Traditional phthalic acid ester plasticizers (PAEs), such as dibutyl phthalate (DBP) and bis(2-ethyl hexyl) phthalate (DEHP), are now increasingly being replaced with more environmentally friendly alternatives, such as acetyl tributyl citrate (ATBC). While the metabolic pathways for PAE degradation have been established in the terrestrial environment, to our knowledge, the mechanisms for ATBC biodegradation have not been identified previously and plasticizer degradation in the marine environment remains underexplored. From marine plastic debris, we enriched and isolated microbes able to grow using a range of plasticizers and, for the first time, identified the pathways used by two phylogenetically distinct bacteria to degrade three different plasticizers (i.e., DBP, DEHP, and ATBC) via a comprehensive proteogenomic and metabolomic approach. This integrated multi-OMIC study also revealed the different mechanisms used for ester side-chain removal from the different plasticizers (esterases and enzymes involved in the β-oxidation pathway) as well as the molecular response to deal with toxic intermediates, that is, phthalate, and the lower biodegrading potential detected for ATBC than for PAE plasticizers. This study highlights the metabolic potential that exists in the biofilms that colonize plastics-the Plastisphere-to effectively biodegrade plastic additives and flags the inherent importance of microbes in reducing plastic toxicity in the environment.

Occurrence, distribution, and sources of phthalates and non-phthalate plasticizers in sediment from semi-enclosed bays of Korea

Due to strong regulation of phthalates, non-phthalate plasticizers (NPPs) have been introduced to the industrial market. In this study, concentrations of 16 phthalates and five NPPs in sediment were measured to investigate the occurrence, potential source, and ecotoxicological implications of these contaminants. Phthalates and NPPs were detected in all sediment samples, indicating ubiquitous contaminants. Di(2-ethylhexyl)phthalate (DEHP) and trioctyl trimellitate (TOTM) were the dominant for phthalates and NPPs, respectively, implying emerging contamination by TOTM. Spatial distribution of these contaminants showed decreasing gradients from inner to outer bays. Clear declining trends in phthalate and NPP concentrations were found in sediment near a wastewater treatment plant outfall, suggesting a potential source of contamination. Approximately 95% of sediment samples exceeded sediment quality guidelines for DEHP suggested by previous studies, implying that benthic organisms are suffering from adverse biological effects. This is the first report on the occurrence of NPPs in the coastal environment.

Sources of clinically significant neonatal intensive care unit phthalate exposure

In the United States each year, more than 300,000 infants are admitted to neonatal intensive care units (NICU) where they are exposed to a chemical-intensive hospital environment during a developmentally vulnerable period. Although multiple studies have demonstrated elevated phthalate biomarkers in NICU patients, specific sources of NICU-based phthalate exposure have not been identified.In this study, premature newborns with birth weight <1500 g were recruited to participate in a prospective environmental health cohort during the NICU hospitalization. Exposure to specific NICU equipment was recorded daily during the NICU hospitalization. One hundred forty-nine urine specimens from 71 infants were analyzed for phthalate metabolites using high-performance liquid chromatography/tandem mass spectrometry.In initial analyses, exposure to medical equipment was directly related to phthalate levels, with DEHP biomarkers 95-132% higher for infants exposed to specific medical equipment types compared to those without that equipment exposure (p < 0.001-0.023). This association was mirrored for clinically relevant phthalate mixtures whether composed of DEHP metabolites or not (p = 0.002-0.007). In models accounting for concurrent equipment use, exposure to respiratory support was associated with DEHP biomarkers 50-136% higher in exposed compared to unexposed infants (p = 0.007-0.036). Phthalate mixtures clinically relevant to neurobehavioral development were significantly associated with non-invasive respiratory support (p = 0.008-0.026). Feeding supplies and intravenous lines were not significantly associated with clinically important phthalate mixtures.Respiratory support equipment may be a significant and clinically relevant NICU source of phthalate exposure. Although manufacturers have altered feeding and intravenous supplies to reduce DEHP exposure, other sources of exposure to common and clinically impactful phthalates persist in the NICU.

Association of exposure to phthalates with cardiometabolic risk factors in children and adolescents: a systematic review and meta-analysis

Recent studies revealed controversial results on the association of exposure to phthalates with cardiometabolic risk factors in children and adolescents. Therefore, this systematic review and meta-analysis was conducted in this regard. At first, we searched English-language papers in Scopus, Web of Science, and PubMed databases, with no restriction of time, till the end of the year 2018. We performed a comprehensive literature search for association between phthalate exposure and cardiometabolic risk factors including obesity, hypertension, hyperglycemia, and dyslipidemia. Among 99 published papers found in scientific databases, 17 cohort, 15 cross-sectional, and three case-control studies were included in the meta-analysis. We observed a significant association between the concentrations of phthalates and their metabolites with body mass index (BMI), BMI z-score, waist circumference (WC), and low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), and glucose in serum. In addition, significant association was observed between prenatal phthalate exposure and birth weight. To the best of our knowledge, this is the first meta-analysis of its kind. It shows positive association between phthalate exposure and some cardiometabolic risk factors in children and adolescents. Therefore, prevention of exposure to phthalates and reduction of their use should be underscored in strategies for primordial prevention of cardiovascular diseases. Recent studies revealed controversial results on the association of exposure to phthalates with cardiometabolic risk factors in children and adolescents. Therefore, this systematic review and meta-analysis was conducted in this regard.

In vitro exposure to the next-generation plasticizer diisononyl cyclohexane-1,2-dicarboxylate (DINCH): cytotoxicity and genotoxicity assessment in human cells

Plasticizers are currently present in many consumer products, particularly food packaging, children's toys, and medical devices. There are concerns regarding potential leaching to environment or food, thus increasing the risk of human exposure by inhalation, ingestion and/or dermal absorption potentially leading to adverse health consequences. Hexamoll diisononyl cyclohexane-1,2-dicarboxylate (Hexamoll® DINCH®), a non-phthalate plasticizer, has been used as a safer alternative to hazardous phthalates. In contrast to phthalates, evidence indicates that DINCH did not produce endocrine disruption, reproductive dysfunctions, genotoxicity or mutagenicity. However, there are limited data available regarding safety assessment, especially with respect to genotoxicity in human cells. The aim of this study was to assess DINCH cytotoxic and genotoxic effects in human liver and kidney cell lines following several exposure periods. For this purpose, the MTT cell viability, micronucleus, conventional and formamidopyrimidine DNA glycosylase (FPG)-modified comet assays were employed to detect cell death and genotoxicity, respectively. Data demonstrated that DINCH induced cytotoxicity in kidney cells exposed for 48hr, but not in liver cells. No marked chromosomal damage was noted after short-term or longer following treatment of both cell lines. However, DINCH produced oxidative DNA damage in liver cells exposed for 3 h, which decreased after a more prolonged incubation period. The occurrence of oxidative lesions, even transiently, indicates that mutation fixation may occur leading to adverse effects in liver. Therefore, these findings suggest that DINCH may be hazardous to humans and that further investigation is necessary to warrant its safety.

New SPE-LC-MS/MS method for the simultaneous determination in urine of 22 metabolites of DEHP and alternative plasticizers from PVC medical devices

DiEthylHexylPhthalate (DEHP) can leach out of plasticized PVC medical devices (MD) and may enter into contact with patients. This phthalate is known for its reprotoxic and endocrine disrupting effects. Its use in medical devices (MD) has been restricted and alternative plasticizers have been developed. Nevertheless, no published clinical studies exist concerning patient exposure to these alternative plasticizers during medical care. This is particularly worrisome when high-risk populations, such as newborns, are exposed to these new plasticizers in intensive care units. Our study aimed to develop a novel sensitive and selective method to simultaneously identify and quantify DEHP and 17 other plasticizer metabolites (free or glucuronide conjugates), which are specific biomarkers of DEHTP, TOTM, DINP, DINCH and DEHA exposure in human urine. This robust method uses turbulent-flow online extraction technology coupled to high performance liquid chromatography - tandem mass spectrometry. Special care was taken to address two major problems in plasticizer analysis: contamination and chromatographic separation of interfering analogue structures. The validation was assessed in synthetic urine and the linearity of response was demonstrated for all compounds (R² > 0.99), with limits of quantification from 0.01 to 0.1 ng/ml. Accuracies ranged from 86% to 117% and inter- and intra-day precisions were <20%. The clinical applicability and suitability of our new method was assessed in patients in a neonatal intensive care unit to measure urinary concentrations of DEHP and alternative plasticizer metabolites. These metabolites were found in the majority of urine samples, with a median detection frequency of 95.2% (ranging from 12.5% to 100%). The high sensitivity, selectivity and ruggedness make the method suitable for large-scale biomonitoring studies of high-risk and general populations.

Municipal leachates health risks: Chemical and cytotoxicity assessment from regulated and unregulated municipal dumpsites in Lebanon

The proper management of municipal waste is critical for resource recovery, sustainability and health. Lebanon main approach for managing its municipal waste consisted of landfill disposal with minimal recycling capacity. This approach contributed to exceeding the holding capacity of existing landfills leading eventually to their closures. The closure of a major landfill (Naameh landfill) servicing Beirut and Mount Lebanon areas led to municipal wastes piling in the streets and forests for more than a year in 2016. The main problem identified in the municipal wastes consisted of untreated leachates (from regulated and unregulated dumpsites) going straight into the Mediterranean Sea. Therefore leachate samples were collected and subjected to chemical characterization followed by biological assessment. The chemical characterization and profiling of the Lebanese leachates were compared to results reported in Lebanon, Europe and United States as well as to the toxicity reference values (TRV). The biological assessment was conducted in vitro using human derived immortalized cell cultures. This strategy revealed significant alarming cellular organelles and DNA damages using in vitro cytotoxicity assays (MTS and comet assay). The significant damages observed at the cellular level prompted further animal model investigations using BALB/c mice. The animal data pointed to significant upregulation of liver activity enzymes coupled with significant damage expression in liver spleen and bone marrow DNA. The presented research clearly indicated that there is an urgent need for development of national waste strategies for proper treatment and disposal of municipal waste leachates in Lebanon.

Temporal trends of phthalate exposures during 2007-2010 in Swedish pregnant women

BACKGROUND

The general population is exposed to phthalates, a group of chemicals with strong evidence for endocrine disrupting properties, commonly used in a large number of consumer products. Based on published research and evidence compiled by environmental agencies, certain phthalate applications and products have become restricted, leading to an increasing number of "new generation compounds" coming onto the market during recent years replacing older phthalates. Some examples of such newer compounds are di-iso-nonyl phthalate (DiNP), di-iso-decyl phthalate (DiDP), and most recently di-isononyl-cyclohexane-1,2-dicarboxylate (DiNCH).

OBJECTIVES

In order to evaluate temporal trends in phthalate exposure, first trimester urinary biomarkers of phthalates were measured in the Swedish SELMA study over a period of 2.5 years (2007-2010).

METHODS

We collected first morning void urine samples around week 10 of pregnancy from 1651 pregnant women. Spot samples were analyzed for 13 phthalate metabolites and one phthalate replacement and least square geometric mean (LSGM) levels of the metabolites were compared between the sampling years when adjusted for potential confounders.

RESULTS

All 14 metabolites were detectable in more than 99% of the SELMA subjects. The levels were generally comparable to other studies, but the SELMA subjects showed slightly higher exposure to butyl-benzyl phthalate (BBzP) and di-butyl phthalate (DBP). Di-ethyl-hexyl phthalate (DEHP) metabolites levels decreased while DiNP, DiDP/di-2-propylheptyl phthalate (DPHP), and DiNCH metabolites levels increased during the sampling period.

CONCLUSIONS

Urinary metabolite levels of the older phthalates and more recently introduced phthalate replacement compound changed during the short sampling period in this Swedish pregnancy cohort. Our results indicate that replacement of phthalates can make an impact on human exposure to these chemicals. During this particularly vulnerable stage of life, phthalate exposures are of particular concern as the impacts, though not immediately noticeable, may increase the risk for health effects later in life.

Neonatal intensive care unit phthalate exposure and preterm infant neurobehavioral performance

Every year in the United States, more than 300,000 infants are admitted to neonatal intensive care units (NICU) where they are exposed to a chemical-intensive hospital environment during a developmentally vulnerable period. The neurodevelopmental impact of environmental exposure to phthalates during the NICU stay is unknown. As phthalate exposure during the third trimester developmental window has been implicated in neurobehavioral deficits in term-born children that are strikingly similar to a phenotype of neurobehavioral morbidity common among children born premature, the role of early-life phthalate exposure on the neurodevelopmental trajectory of premature infants may be clinically important. In this study, premature newborns with birth weight <1500g were recruited to participate in a prospective environmental health cohort study, NICU-HEALTH (Hospital Exposures and Long-Term Health), part of the DINE (Developmental Impact of NICU Exposures) cohort of the ECHO (Environmental influences on Child Health Outcomes) program. Seventy-six percent of eligible infants enrolled in the study. Sixty-four of 81 infants survived and are included in this analysis. 164 urine specimens were analyzed for phthalate metabolites using high-performance liquid chromatography/tandem mass spectrometry. The NICU Network Neurobehavioral Scale (NNNS) was performed prior to NICU discharge. Linear and weighted quantile sum regression quantified associations between phthalate biomarkers and NNNS performance, and between phthalate biomarkers and intensity of medical intervention. The sum of di(2-ethylhexyl) phthalate metabolites (∑DEHP) was associated with improved performance on the Attention and Regulation scales. Specific mixtures of phthalate biomarkers were also associated with improved NNNS performance. More intense medical intervention was associated with higher ∑DEHP exposure. NICU-based exposure to phthalates mixtures was associated with improved attention and social response. This suggests that the impact of phthalate exposure on neurodevelopment may follow a non-linear trajectory, perhaps accelerating the development of certain neural networks. The long-term neurodevelopmental impact of NICU-based phthalate exposure needs to be evaluated.

Contamination levels and potential sources of organic pollution in an Asian river

The Houjing River has long been an environmental victim of economic development. Industries that have settled along the bank of this river may have largely contributed to severe organic wastes pollution. This study collected water and sediment samples at various points along the river and measured concentrations of 61 volatile organic compounds (VOCs) and 128 semi-volatile organic compounds (SVOCs) for a period of 16 months (Feb 2014-June 2015). Our analyses show that elevated levels of VOCs were observed near two industrial areas, Dashe and Renwu industrial parks. High SVOC concentrations were found in the vicinities of the Nanzih Export Processing Zone (NEPZ) and CingPu station, possibly due to considerable effluent discharges of adjacent industrial and residential areas. Comparing this study's findings with the standard values of different governmental agencies and studies similar to this one, the ecosystem of the Houjing River was seriously contaminated. This study could be used by the government as a basis for future and urgent pollution prevention actions aimed at protecting this ecosystem and reducing the negative impacts of these contaminants on the health and well-being of the local residents and the environment.

Epigenetic impact of endocrine disrupting chemicals on lipid homeostasis and atherosclerosis: a pregnane X receptor-centric view

Despite the major advances in developing diagnostic techniques and effective treatments, atherosclerotic cardiovascular disease (CVD) is still the leading cause of mortality and morbidity worldwide. While considerable progress has been achieved to identify gene variations and environmental factors that contribute to CVD, much less is known about the role of "gene-environment interactions" in predisposing individuals to CVD. Our chemical environment has significantly changed in the last few decades, and there are more than 100,000 synthetic chemicals in the market. Recent large-scale human population studies have associated exposure to certain chemicals including many endocrine disrupting chemicals (EDCs) with increased CVD risk, and animal studies have also confirmed that some EDCs can cause aberrant lipid homeostasis and increase atherosclerosis. However, the underlying mechanisms of how exposure to those EDCs influences CVD risk remain elusive. Numerous EDCs can activate the nuclear receptor pregnane X receptor (PXR) that functions as a xenobiotic sensor to regulate host xenobiotic metabolism. Recent studies have demonstrated the novel functions of PXR in lipid homeostasis and atherosclerosis. In addition to directly regulating transcription, PXR has been implicated in the epigenetic regulation of gene transcription. Exposure to many EDCs can also induce epigenetic modifications, but little is known about how the changes relate to the onset or progression of CVD. In this review, we will discuss recent research on PXR and EDCs in the context of CVD and propose that PXR may play a previously unrealized role in EDC-mediated epigenetic modifications that affect lipid homeostasis and atherosclerosis.

Isomeric separation and quantitation of di-(2-ethylhexyl) trimellitates and mono-(2-ethylhexyl) trimellitates in blood by LC-MS/MS

A new and fast HPLC-method for the simultaneous determination of tri-(2-ethylhexyl) trimellitate (TOTM or TEHTM), its diesters 2,4-di-(2-ethylhexyl) trimellitate (2,4-DEHTM), 1,4-di-(2-ethylhexyl) trimellitate (1,4-DEHTM), 1,2-di-(2-ethylhexyl) trimellitate (1,2-DEHTM) and monoesters 1-mono-(2-ethylhexyl) trimellitate (1-MEHTM), 2-mono-(2-ethylhexyl) trimellitate (2-MEHTM) and 4-mono-(2-ethylhexyl) trimellitate (4-MEHTM) together with di-(2-ethylhexyl) phthalate (DEHP) and its primary metabolite mono-(2-ethylhexyl) phthalate (MEHP) in blood was developed and validated. The analytes are extracted from blood using liquid-liquid extraction and are chromatographically separated by reversed-phase HPLC using core shell material. Quantitative assessment was performed by ESI-tandem mass spectrometry in negative ionization mode using stable isotope dilution. In less than 30min six postulated primary metabolites of TOTM along with the DEHP metabolite MEHP can be selectively and sensitively quantified. Additionally, the method enables the determination of the parent plasticizers TOTM and DEHP. The detection limits in blood were found to range between 0.7-5.5μg/L for all TOTM analytes. Precision and repeatability of the method were proven by relative standard deviations between 0.9% and 8.7%. TOTM, an alternative plasticizer to DEHP, is already increasingly used for medical devices. Nevertheless, data about the human metabolism of TOTM are still limited. The presented method is the first one enabling the simultaneous determination of the parent plasticizers TOTM and DEHP together with their primary degradation products (DEHTM, MEHTM, MEHP) and can thus be applied manifold including the investigation of the human metabolism of TOTM.

Exposure to endocrine disruptors during adulthood: consequences for female fertility

Endocrine disrupting chemicals are ubiquitous chemicals that exhibit endocrine disrupting properties in both humans and animals. Female reproduction is an important process, which is regulated by hormones and is susceptible to the effects of exposure to endocrine disrupting chemicals. Disruptions in female reproductive functions by endocrine disrupting chemicals may result in subfertility, infertility, improper hormone production, estrous and menstrual cycle abnormalities, anovulation, and early reproductive senescence. This review summarizes the effects of a variety of synthetic endocrine disrupting chemicals on fertility during adult life. The chemicals covered in this review are pesticides (organochlorines, organophosphates, carbamates, pyrethroids, and triazines), heavy metals (arsenic, lead, and mercury), diethylstilbesterol, plasticizer alternatives (di-(2-ethylhexyl) phthalate and bisphenol A alternatives), 2,3,7,8-tetrachlorodibenzo-p-dioxin, nonylphenol, polychlorinated biphenyls, triclosan, and parabens. This review focuses on the hypothalamus, pituitary, ovary, and uterus because together they regulate normal female fertility and the onset of reproductive senescence. The literature shows that several endocrine disrupting chemicals have endocrine disrupting abilities in females during adult life, causing fertility abnormalities in both humans and animals.

Leaching of plasticizers from polyvinylchloride perfusion lines by different lipid emulsions for premature infants under clinical conditions

Plasticizers migrate from polyvinylchloride (PVC) infusion systems into lipid emulsions. The aim of this study was to investigate the leaching of different plasticizers from PVC perfusion lines by a selection of lipid emulsions under clinical conditions. Seven PVC perfusion lines with an equal length of 150cm and three internal diameters were perfused with three lipid emulsions: Intralipid^® 20%, ClinOleic^® 20% and SMOFlipid^® 20%, mimicking clinical conditions. The concentrations of the plasticizers were measured directly in the emulsions by gas chromatography - mass spectrometry. Of the four plasticizers examined in this study, di (2-ethylhexyl) phthalate (DEHP) leached the most and was found, on average, at 46.5μg/ml in the emulsions - around one order of magnitude higher than the other plasticizers. This study demonstrates that the leaching of DEHP by lipid emulsions in conditions of total parenteral nutrition is many times higher than should be accepted and higher when compared to the other plasticizers. There was no significant difference in leaching of plasticizers in relation to the type of lipid emulsion. The influence of tube diameter on the leaching rate of plasticizers should be taken into account especially in particular exposed patients.

In vitro functional screening as a means to identify new plasticizers devoid of reproductive toxicity

Plasticizers are indispensable additives providing flexibility and malleability to plastics. Among them, several phthalates, including di (2-ethylhexyl) phthalate (DEHP), have emerged as endocrine disruptors, leading to their restriction in consumer products and creating a need for new, safer plasticizers. The goal of this project was to use in vitro functional screening tools to select novel non-toxic plasticizers suitable for further in vivo evaluation. A panel of novel compounds with satisfactory plasticizer properties and biodegradability were tested, along with several commercial plasticizers, such as diisononyl-cyclohexane-1,2-dicarboxylate (DINCH®). MEHP, the monoester metabolite of DEHP was also included as reference compound. Because phthalates target mainly testicular function, including androgen production and spermatogenesis, we used the mouse MA-10 Leydig and C18-4 spermatogonial cell lines as surrogates to examine cell survival, proliferation, steroidogenesis and mitochondrial integrity. The most promising compounds were further assessed on organ cultures of rat fetal and neonatal testes, corresponding to sensitive developmental windows. Dose-response studies revealed the toxicity of most maleates and fumarates, while identifying several dibenzoate and succinate plasticizers as innocuous on Leydig and germ cells. Interestingly, DINCH®, a plasticizer marketed as a safe alternative to phthalates, exerted a biphasic effect on steroid production in MA-10 and fetal Leydig cells. MEHP was the only plasticizer inducing the formation of multinucleated germ cells (MNG) in organ culture. Overall, organ cultures corroborated the cell line data, identifying one dibenzoate and one succinate as the most promising candidates. The adoption of such collaborative approaches for developing new chemicals should help prevent the development of compounds potentially harmful to human health.

Comparative study on the migration of di-2-ethylhexyl phthalate (DEHP) and tri-2-ethylhexyl trimellitate (TOTM) into blood from PVC tubing material of a heart-lung machine

Medical devices like blood tubing often consist of PVC material that requires the addition of plasticizers. These plasticizers may migrate into the blood leading to an exposure of the patients. In this study the migration behavior of three different blood tubing sets (PVC material with two different plasticizers and silicone as control material) applied on a heart-lung machine standardly used for cardiopulmonary bypass (CPB) in children was studied. We analyzed the total plasticizer migration by analysis of both, the parent compounds as well as their primary degradation products in blood. Additionally, the total mass loss of the tubing over perfusion time was examined. The PVC tubing plasticized with DEHP (di-2-ethylhexyl phthalate) was found to have the highest mass loss over time and showed a high plasticizer migration rate. In comparison, the migration of TOTM (tri-2-ethylhexyl trimellitate) and its primary degradation products was found to be distinctly lower (by a factor of approx. 350). Moreover, it was observed that the storage time of the tubing affects the plasticizer migration rates. In conclusion, the DEHP substitute TOTM promises to be an effective alternative plasticizer for PVC medical devices particularly regarding the decreased migration rate during medical procedures.