Eleven phthalate esters and di(2-ethylhexyl) adipate in oneweek duplicate diet samples obtained from hospitals and their estimated daily intake

Disposable gloves: An innate source of transferable chemical residues

As workers in medicine, food science, and advanced manufacturing have learned, pristine disposable gloves are an innate source of chemical contamination from the moment they are first donned. Given the typically low extent of chemical contamination on the surface of gloves post-manufacture, many fields overlook, or simply discount, this source of transferable chemical evidence. However, forensic science should not adopt this approach. Instead, the trace chemical signatures left after handling objects while wearing different brands and types of disposable gloves could provide new avenues of forensic intelligence when assessing crime scenes. Similarly, an appreciation of the potential for disposable gloves to transfer innate chemical residues is an important consideration when surface analyses of evidence are envisioned. This review summarises past reports of chemical transference originating from pristine gloves drawn from the fields of medicine, food science, and material science, as well as the few examples highlighting the implications of such events for forensic investigations. Correlations between the chemical identities of the contaminants and the material of glove manufacture are provided here where known, with energy-intensive chemical extraction of glove material, and passive transference of chemical residues through simple contact, both explored. Finally, discussions pertaining to the implications of disposable glove residues, coupled with opportunities for future research, are outlined.

A Review of the Analysis of Phthalates by Gas Chromatography in Aqueous and Food Matrices

As a commonly well-known industrial chemical, phthalates are produced in high volumes to be used in various consumer products (e.g., plasticizers, medical devices, construction materials, and toys) to enhance softness, durability, transparency, and flexibility. Phthalates are generally not chemically bonded to the polymer chain of the plastic in which they are mixed. Thus, they may leach, migrate, or evaporate into indoor/outdoor air, and foodstuffs. In this review, a comprehensive overview of several sample preparation methods coupled with gas chromatography for the analysis of phthalates in various kinds of complex matrices, with a focus on the last 20 years' worth of papers. The review begins by highlighting the environmental significance of phthalate pollution along with the various routes to their exposure to general population. Then, the discussion is extended to cover the pretreatment and extraction techniques for phthalates for their quantitation based on gas chromatographic approach. Finally, the present and future challenges for the detection of phthalates in aqueous and food matrices are discussed.

Phthalate and novel plasticizer concentrations in food items from U.S. fast food chains: a preliminary analysis

BACKGROUND

Fast food consumption is associated with biomarkers of ortho-phthalates exposures. However, the chemical content of fast food is unknown; certain ortho-phthalates (i.e., di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP)) have been phased out and replaced with other plasticizers (e.g., dioctyl terephthalate (DEHT)).

OBJECTIVE

We conducted a preliminary study to examine ortho-phthalate and replacement plasticizer concentrations in foods and food handling gloves from U.S. fast food restaurants.

METHODS

We obtained hamburgers, fries, chicken nuggets, chicken burritos, cheese pizza (n = 64 food samples) and gloves (n = 3) from restaurants and analyzed them for 11 chemicals using gas chromatography mass spectrometry.

RESULTS

We found DEHT at the highest concentrations in both foods (n = 19; median = 2510 µg/kg; max = 12,400 µg/kg) and gloves (n = 3; range: 28-37% by weight). We detected DnBP and DEHP in 81% and 70% of food samples, respectively. Median DEHT concentrations were significantly higher in burritos than hamburgers (6000 µg/kg vs. 2200 µg/kg; p < 0.0001); DEHT was not detected in fries. Cheese pizza had the lowest levels of most chemicals.

SIGNIFICANCE

To our knowledge, these are the first measurements of DEHT in food. Our preliminary findings suggest that ortho-phthalates remain ubiquitous and replacement plasticizers may be abundant in fast food meals.

IMPACT STATEMENT

A selection of popular fast food items sampled in this study contain detectable levels of replacement plasticizers and concerning ortho-phthalates. In addition, food handling gloves contain replacement plasticizers, which may be a source of food contamination. These results, if confirmed, may inform individual and regulatory exposure reduction strategies.

The sex-specific association of prenatal phthalate exposure with low birth weight and small for gestational age: A nationwide survey by the Taiwan Maternal and Infant Cohort Study (TMICS)

The Taiwan Maternal and Infant Cohort Study (TMICS) was launched with the aim to assess the effects of prenatal exposure to phthalic acid esters (PAEs) on infant health. A total of 1102 pregnant women were enrolled in this study from 2012 to 2015. All participants completed a structured questionnaire, and provided urine specimens. The urinary concentrations of PAE metabolites in the third trimester were measured using liquid chromatography-electrospray ionization tandem mass spectrometry. Generalized additive model-penalized regression splines and logistic regression models were employed to determine the risk for low birth weight (LBW) or small for gestational age (SGA) among pregnant women exposed to PAEs. After adjustments for other covariates, each incremental unit of ln-transformed mono-n-butyl phthalate (MnBP) for pregnant women increased the odds of SGA in male neonates by 1.44 (95% CI: 0.92-2.23). An inverse association between SGA and maternal MnBP exposure level was observed in female neonates. An increase in one ln-transformed MnBP concentration unit decreased the risk of female SGA to 0.50 (95% CI: 0.24-0.97). In the penalized regression splines, increased risks of LBW/SGA in male neonates were presented while pregnant women exposed to increased MnBP levels. However, an association in the opposite direction was observed between maternal MnBP and LBW or SGA for male and female neonates. This study indicated that high maternal MnBP exposure in the third trimester was associated with LBW or SGA for male infants. Adverse effects on susceptible populations exposed to high levels of PAEs should be of concern.

Biochemical and molecular changes mediated by plasticizer diethyl phthalate in Chironomus circumdatus (bloodworms)

Plasticizers are used as additives in making plastics. Diethyl phthalate (DEP) is one of the majorly used plasticizers in various products. When plastic materials are dumped in an aquatic system, there is an increase in chances of DEP leaching out and getting deposited in water. Thus the current work focuses on studying the effect of DEP on the larval stages of Chironomus circumdatus. In this study it was found that there was an increase in lipid peroxidation levels indicating imposition of oxidative stress on these larvae due to the exposure of DEP. Changes in the levels of carbohydrates and lipids were also seen. To reduce these effects antioxidant defense system may get activated. Thus investigations showed an increase in enzymatic activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and acetylcholinesterases (AchE) and decrease in the activity of glutathione reductase (GR). Nonenzymatic antioxidant glutathione levels were also increased during the post-recovery exposure period. Thus this indicates that both enzymatic, as well as non-enzymatic antioxidants, play a certain role in reducing the stress mediated by DEP. Up-regulation of gene expression of heat shock protein70 (hsp70) was observed, which is one of the conserved protein produced during stress response in many dipterans. Changes in the level of expression of the ecdysone receptor (EcR) gene were also seen in DEP exposed larvae. Thus the insights give us a preliminary indication that physiological and developmental adaptations may take place in these organisms to persist in the DEP contaminated environment. CAPSULE: DEP mediated stress imposes changes in the metabolites and thus activation of antioxidant defense system in aquatic midges of Chironomus circumdatus. Changes in the expression of heat shock protein70 and ecdysone receptor was also seen indicating that DEP mediated stress affects at the molecular level also of the organism. These changes may help them to tolerate and live in DEP polluted water.

The solvent effects on dimethyl phthalate investigated by FTIR characterization, solvent parameter correlation and DFT computation

This study set out with the aim of investigating the solvent effects on dimethyl phthalate (DMP) using FTIR characterization, solvent parameter correlation and DFT calculation. DMP exposed to 17 organic solvents manifested varying shift in the carbonyl stretching vibration frequency (ν_CO). Non-alkanols induced Band I and alkanols produced Band I and Band II. Through correlating the ν_CO with the empirical solvent scales including acceptor parameter (AN), Schleyer's linear free energy parameter (G), and linear free salvation energy relationships (LSER), Band I was mainly ascribed to non-specific effects from either non-alkanols or alkanol polymers ((alkanol)_n). ν_CO of the latter indicated minor red shift and less variability compared to the former. An assumption was made and validated about the sequestering of hydroxyl group by the bulky hydrophobic chain in (alkanol)_n, creating what we refer to as "screening effects". Ab initio calculation, on the other hand, provided insights for possible hydrogen binding between DMP and (ethanol)_n or between ethanol monomers. The two components of Band I observed in inert solvents were assigned to the two CO groups adopting differentiated conformations. This in turn prompted our consideration that hydrogen binding was highly selective in favor of lowly associated (alkanol)_n and the particular CO group having relatively less steric hindrance and stronger electron-donating capacity. Band II was therefore believed to derive from hydrogen-bond interactions mainly in manner of 1:1 and 1:2 DMP-(alkanol)_n complexes.

Dietary sources of cumulative phthalates exposure among the U.S. general population in NHANES 2005-2014

BACKGROUND

Anti-androgenic phthalates are reproductive toxicants that may have additive effects on male development. Diet is the primary exposure source for most phthalates, which contaminate the food supply through food contact materials and industrialized production.

OBJECTIVE

To compare dietary sources of cumulative phthalates exposure between "food at home" (e.g. food consumed from a grocery store) and "food away from home" (e.g. food consumed from fast food/restaurants and cafeterias) in the U.S. general population.

METHODS

We estimated cumulative phthalates exposure by calculating daily intake from metabolite concentrations in urinary spot samples for 10,253 participants (≥6 years old) using National Health and Nutrition Examination Survey (NHANES, 2005-2014) data. We constructed a biologically relevant metric of phthalates daily intake (∑androgen-disruptor, μg/kg/day) by converting phthalates into anti-androgen equivalent terms prior to their summation. Particular foods and the percent of total energy intake (TEI) consumed from multiple dining out sources were ascertained from 24-h recall surveys. Associations with ∑androgen-disruptor levels were estimated for children, adolescents, and adults using multivariable linear regression.

RESULTS

We observed a consistent positive association between dining out and Σandrogen-disruptor levels across the study population (p-trend <0.0001). Among adolescents, high consumers of foods outside the home had 55% (95% CI: 35%, 78%) higher Σandrogen-disruptor levels compared to those who only consumed food at home. The contribution of specific dining out sources to Σandrogen-disruptor levels varied by age group. For example, cafeteria food was associated with 15% (95% CI: 4.0%, 28%) and 64% (95% CI: 40%, 92%) higher Σandrogen-disruptor levels in children and adults, respectively. Particular foods, especially sandwiches (i.e. cheeseburgers), were associated with increased Σandrogen-disruptor levels only if they were purchased away from home (p < 0.01).

CONCLUSION

Dining out may be an important source of biologically relevant cumulative phthalates exposure among the U.S.

POPULATION

Future studies should evaluate modifiable production practices that remove phthalates from the food supply in addition to the efficacy of interventions that promote eating fresh foods prepared at home.

Exposure of hospitalised pregnant women to plasticizers contained in medical devices

Background

Medical devices (MDs) in polyvinyl chloride (PVC) are not a well-known source of exposure to plasticizers, in particular during pregnancy. Because of its toxicity, the di-(2-ethylhexyl) phthalate (DEHP) has been replaced by other plasticizers such as di (isononyl)-cyclohexane-1,2-dicarboxilic acid (DINCH), tri-octyltrimellitate (TOTM) and di-(isononyl) phthalate (DiNP). Our study aimed to quantify the plasticizers (DEHP and alternative plasticizers) contained in PVC medical devices used for hospitalised pregnant women and to describe which these MDs had been used (type, number, duration of exposure).

Methods

The plasticizers contained in the MDs used for daily care in the Obstetrics Department of a French University Hospital were extracted from PVC (after contact with a chloroform solution), identified and quantified by gas-chromatography-mass-spectrometry analysis. A total of 168 pregnant women hospitalised in the Obstetrics Department with at least one catheter were included in the observational study. The median number of MDs containing plasticizers used and the daily duration of exposure to the MDs were compared in three groups of pregnant women: “Pathology group” (women hospitalised for an obstetric disorder who did not give birth during this hospitalisation; n = 52), “Pathology and delivery group” (hospitalised for an obstetric disorder and who gave birth during this stay; n = 23) and “Delivery group” (admitted for planned or spontaneous delivery without obstetric disorder; n = 93).

Results

DiNP, TOTM and DINCH were the predominant plasticizers contained in the MDs at an amount of 29 to 36 g per 100 g of PVC. Women in the “Pathology group” (preterm labour or other pathology) were exposed to a median number of two MDs containing TOTM and one MD containing DiNP, fewer than those in the “Pathology and delivery group” (p < 0.05). Women in the “Pathology group” had a median exposure of 3.4 h/day to MDs containing DiNP and 8.2 h/day to MDs containing TOTM, longer than those in the “Delivery group” (p < 0.01).

Conclusions

Our study shows that the medical management of pregnant women in a hospital setting entails exposure to MDs containing alternative plasticizers (DiNP, TOTM and DINCH).

Electronic supplementary material

The online version of this article (doi:10.1186/s12905-017-0398-7) contains supplementary material, which is available to authorized users.

Recent Fast Food Consumption and Bisphenol A and Phthalates Exposures among the U.S. Population in NHANES, 2003-2010

BACKGROUND

Phthalates and bisphenol A (BPA) are widely used industrial chemicals that may adversely impact human health. Human exposure is ubiquitous and can occur through diet, including consumption of processed or packaged food.

OBJECTIVE

To examine associations between recent fast food intake and BPA and urinary metabolites of di(2-ethylhexyl) phthalate (ΣDEHPm) and diisononyl phthalate (DiNPm) among the U.S.

POPULATION

METHODS

We combined data on 8,877 participants from the National Health and Nutrition Examination Survey (NHANES 2003-2010). Using 24-hr dietary recall data, we quantified: a) fast food intake [percent of total energy intake (TEI) from fast food]; b) fast food-derived fat intake (percent of TEI from fat in fast food); and c) fast food intake by food group (dairy, eggs, grains, meat, and other). We examined associations between dietary exposures and urinary chemical concentrations using multivariate linear regression.

RESULTS

We observed evidence of a positive, dose-response relationship between fast food intake and exposure to phthalates (p-trend < 0.0001) but not BPA; participants with high consumption (≥ 34.9% TEI from fast food) had 23.8% (95% CI: 11.9%, 36.9%) and 39.0% (95% CI: 21.9%, 58.5%) higher levels of ΣDEHPm and DiNPm, respectively, than nonconsumers. Fast food-derived fat intake was also positively associated with ΣDEHPm and DiNPm (p-trend < 0.0001). After adjusting for other food groups, ΣDEHPm was associated with grain and other intake, and DiNPm was associated with meat and grain intake.

CONCLUSION

Fast food may be a source of exposure to DEHP and DiNP. These results, if confirmed, could inform individual and regulatory exposure reduction strategies.

CITATION

Zota AR, Phillips CA, Mitro SD. 2016. Recent fast food consumption and bisphenol A and phthalates exposures among the U.S. population in NHANES, 2003-2010. Environ Health Perspect 124:1521-1528; http://dx.doi.org/10.1289/ehp.1510803.

Toxicologically relevant phthalates in food

Various phthalates have been detected in a wide range of food products such as milk, dietary products, fat-enriched food, meat, fish, sea food, beverages, grains, and vegetables as well as in breast milk. Here we present an overview on toxicologically considerable phthalate levels in food reported in the literature. The most common phthalates detected are di-(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DnBP), and di-isobutyl phthalate (DiBP). Milk analyses demonstrate that background levels in unprocessed milk are usually low. However, during processing the phthalate contents may significantly increase due to migration from plastic materials in contact with food. Among dietary products fat-enriched food such as cheese and cream were identified with highest levels of DEHP. Plasticized PVC from tubes, conveyor belts, or disposable gloves used in food processing is an important source for contamination of food, especially of fatty food. Paper and cardboard packaging made from recycled fibers are another important source of contamination. In addition, gaskets used in metal lids for glass jars have been identified as possible source for the contamination of foodstuffs with phthalates. The highest concentrations of DEHP reported (>900 mg kg(-1)) were detected in food of high fat content stored in such glass jars. Beyond classical food, DEHP and DnBP were identified in human breast milk samples as the main phthalate contaminants. Phthalate monoesters and some oxidative metabolites were also quantified in breast milk.

Dietary intake and phthalates body burden in boys and girls

Background

Phthalates are a group of environmental endocrine disruptors and have been ubiquitously applied in industrial field. Few studies had investigated how dietary intake was related with phthalate body burden in children.

To determine the relationship between phthalate body burden and dietary intake among school age children in Shanghai, China.

Methods

Four hundred and thirty schoolchildren aged 8–16 years were recruited in a cross-sectional study with 18 months follow-up in Shanghai, China during 2010–2012. Data of questionnaire-based dietary intake were collected and urinary phthalate concentrations were measured. Associations between frequency of dietary intake and phthalate metabolite concentrations were evaluated by stepwise multiple linear regression model.

Results

Positive association was found between mono-butyl phthalate and seafood, and negative associations were found between mono-butyl phthalate and dried fruits and vegetables. Egg consumption showed negative association with all di-(2-ethylhexyl) phthalate-related metabolites.

Conclusions

Some food types were identified to be associated with phthalate body burden and diet might be a source of phthalate exposure among Chinese schoolchildren.

Dietary predictors of urinary environmental biomarkers in young girls, BCERP, 2004-7

BACKGROUND

Exposures of children to phthalates, parabens, and bisphenol-A (BPA) are of concern because of their hormonal potential. These agents are found in a wide range of foods and packaging. We investigated whether intake of certain foods predict exposures to these chemicals in young girls.

METHODS

Among 1101 girls (6-8 years at enrollment) from the Breast Cancer and Environment Research Program (BCERP) study, we measured urinary exposure biomarkers for phthalates, parabens, and BPA and assessed dietary intake using 24-h recall 2-4 times. We examined the average daily servings of major and minor food groups categorized as 0 to <0.5, 0.5 to <1 and ≥ 1 servings per day. Items included dairy, eggs, fats, fish, fruit, single grains, meat, non-poultry meats, pasta, poultry and vegetables. Covariate-adjusted least squares geometric means and 95% confidence intervals of creatinine-corrected phthalate and phenol metabolite concentrations in urine were calculated in relation to food intake.

RESULTS

Grains, flour and dry mixes and total fish consumption were positively associated with BPA and the sum of four di-2-ethylhexylphthalate (DEHP) urinary metabolite concentrations. Non-fresh vegetables and poultry were both positively associated with BPA and paraben urinary concentrations. Fats, oils and poultry consumption were positively associated with BPA. Whole-fat dairy consumption was associated with ΣDEHP.

CONCLUSIONS

Some foods may contribute to child exposures to certain chemicals, and this may constitute modifiable means to reduce these environmental exposures.

Simultaneous determination of seven phthalic acid esters in beverages using ultrasound and vortex-assisted dispersive liquid-liquid microextraction followed by high-performance liquid chromatography

A sensitive, rapid, and simple high-performance liquid chromatography with UV detection method was developed for the simultaneous determination of seven phthalic acid esters (dimethyl phthalate, dipropyl phthalate, di-n-butyl phthalate, benzyl butyl phthalate, dicyclohexyl phthalate, di-(2-ethylhexyl) phthalate, and di-n-octyl phthalate) in several kinds of beverage samples. Ultrasound and vortex-assisted dispersive liquid-liquid microextraction method was used. The separation was performed using an Intersil ODS-3 column (C18 , 250 × 4.6 mm, 5.0 μm) and a gradient elution with a mobile phase consisting of MeOH/ACN (50:50) and 0.2 M KH2 PO4 buffer. Analytes were detected by a UV detector at 230 nm. The developed method was validated in terms of linearity, limit of detection, limit of quantification, repeatability, accuracy, and recovery. Calibration equations and correlation coefficients (> 0.99) were calculated by least squares method with weighting factor. The limit of detection and quantification were in the range of 0.019-0.208 and 0.072-0.483 μg/L. The repeatability and intermediate precision were determined in terms of relative standard deviation to be within 0.03-3.93 and 0.02-4.74%, respectively. The accuracy was found to be in the range of -14.55 to 15.57% in terms of relative error. Seventeen different beverage samples in plastic bottles were successfully analyzed, and ten of them were found to be contaminated by different phthalic acid esters.

Intake estimates of phthalate esters for South Delhi population based on exposure media assessment

An indirect estimation method was followed to derive exposure levels of fifteen phthalate congeners in urban population of Delhi, India. The exposure media samples were collected from Jawaharlal Nehru University (JNU) campus and Okhla industrial area. GC-MS analysis of the samples indicated di(2-ethylhexyl) phthalate (DEHP) to be the most abundant congener and its estimated total daily intake level reached upto 70 μg kg(-1) d(-1). Out of the studied congeners, intake doses for di-n-butyl phthalate (DnBP) and DEHP, reached levels near or above the established exposure limit. In JNU, DEHP, dimethyl phthalate (DMP) and butyl benzyl phthalate (BBP) had 69% share in combined daily intake of Σ15 phthalates (CDI15); whereas, in Okhla, DEHP, diethyl phthalate (DEP), diisobutyl phthalate (DIBP), DnBP and DMP shared 64% of the CDI15. Food was found to be the major source of exposure contributing 67% and 74% of the estimated CDI15 at JNU and Okhla respectively.

Effects of phthalates on the development and expression of allergic disease and asthma

OBJECTIVE

To review recent evidence relating phthalate exposures to allergies and asthma and to provide an overview for clinicians interested in the relevance of environmental health research to allergy and who may encounter patients with concerns about phthalates from media reports.

DATA SOURCES

PubMed, TOXLINE, and Web of Science were searched using the term phthalate(s) combined with the keywords allergy, asthma, atopy, and inflammation.

STUDY SELECTIONS

Articles were selected based on relevance to the goals of this review. Studies that involved humans were prioritized, including routes and levels of exposure, developmental and early-life exposures, immunotoxicity, and the development of allergic disease.

RESULTS

The general public and those with allergy are exposed to significant levels of phthalates via diet, pharmaceuticals, phthalate-containing products, and ambient indoor environment via air and dust. Intravenous exposures occur through medical equipment. Phthalates are metabolized and excreted quickly in the body with metabolites measured in urine. Phthalates, which are known endocrine disrupting compounds, have been associated with oxidative stress and alterations in cytokine expression. Metabolites in human urine, particularly of the higher-molecular-weight phthalates, have been associated with allergies and asthma in multiple studies.

CONCLUSION

Despite mounting evidence implicating phthalates, causation of allergic disease by these compounds cannot currently be established. In utero and early-life exposures and possible transgenerational effects are not well understood. However, considering the current evidence, reducing exposures to phthalates by avoiding processed and foods packaged and stored in plastics, personal care products with phthalates, polyvinyl chloride materials indoors, and reducing home dust is advised. Further longitudinal, molecular, and intervention studies are needed to understand the association between phthalates and allergic disease.

Children's phthalate intakes and resultant cumulative exposures estimated from urine compared with estimates from dust ingestion, inhalation and dermal absorption in their homes and daycare centers

Total daily intakes of diethyl phthalate (DEP), di(n-butyl) phthalate (DnBP), di(isobutyl) phthalate (DiBP), butyl benzyl phthalate (BBzP) and di(2-ethylhexyl) phthalate (DEHP) were calculated from phthalate metabolite levels measured in the urine of 431 Danish children between 3 and 6 years of age. For each child the intake attributable to exposures in the indoor environment via dust ingestion, inhalation and dermal absorption were estimated from the phthalate levels in the dust collected from the child's home and daycare center. Based on the urine samples, DEHP had the highest total daily intake (median: 4.42 µg/d/kg-bw) and BBzP the lowest (median: 0.49 µg/d/kg-bw). For DEP, DnBP and DiBP, exposures to air and dust in the indoor environment accounted for approximately 100%, 15% and 50% of the total intake, respectively, with dermal absorption from the gas-phase being the major exposure pathway. More than 90% of the total intake of BBzP and DEHP came from sources other than indoor air and dust. Daily intake of DnBP and DiBP from all exposure pathways, based on levels of metabolites in urine samples, exceeded the Tolerable Daily Intake (TDI) for 22 and 23 children, respectively. Indoor exposures resulted in an average daily DiBP intake that exceeded the TDI for 14 children. Using the concept of relative cumulative Tolerable Daily Intake (TDI(cum)), which is applicable for phthalates that have established TDIs based on the same health endpoint, we examined the cumulative total exposure to DnBP, DiBP and DEHP from all pathways; it exceeded the tolerable levels for 30% of the children. From the three indoor pathways alone, several children had a cumulative intake that exceeded TDI(cum). Exposures to phthalates present in the air and dust indoors meaningfully contribute to a child's total intake of certain phthalates. Such exposures, by themselves, may lead to intakes exceeding current limit values.

Phthalate concentrations and dietary exposure from food purchased in New York State

BACKGROUND

Phthalates have been found in many personal care and industrial products, but have not previously been reported in food purchased in the United States. Phthalates are ubiquitous synthetic compounds and therefore difficult to measure in foods containing trace levels. Phthalates have been associated with endocrine disruption and developmental alteration.

OBJECTIVES

Our goals were to report concentrations of phthalates in U.S. food for the first time, specifically, nine phthalates in 72 individual food samples purchased in Albany, New York, and to compare these findings with other countries and estimate dietary phthalate intake.

METHODS

A convenience sample of commonly consumed foods was purchased from New York supermarkets. Methods were developed to analyze these foods using gas chromatography-mass spectroscopy. Dietary intakes of phthalates were estimated as the product of the food consumption rate and concentration of phthalates in that food.

RESULTS

The range of detection frequency of individual phthalates varied from 6% for dicyclohexyl phthalate (DCHP) to 74% for di-2-ethylhexyl phthalate (DEHP). DEHP concentrations were the highest of the phthalates measured in all foods except beef [where di-n-octyl phthalate (DnOP) was the highest phthalate found], with pork having the highest estimated mean concentration of any food group (mean 300 ng/g; maximum, 1,158 ng/g). Estimated mean adult intakes ranged from 0.004 μg/kg/day for dimethyl phthalate (DMP) to 0.673 μg/kg/day for DEHP.

CONCLUSIONS

Phthalates are widely present in U.S. foods. While estimated intakes for individual phthalates in this study were more than an order of magnitude lower than U.S. Environmental Protection Agency reference doses, cumulative exposure to phthalates is of concern and a more representative survey of U.S. foods is indicated.

Biomonitoring of phthalate metabolites in the Canadian population through the Canadian Health Measures Survey (2007-2009)

Human exposure to phthalates occurs through multiple sources and pathways. In the Canadian Health Measures Survey 2007-2009, 11 phthalate metabolites, namely, MMP, MEP, MnBP, MBzP, MCHP, MCPP, MEHP, MEOHP, MEHHP, MnOP, and MiNP were measured in urine samples of 6-49 year old survey respondents (n=3236). The phthalate metabolites biomonitoring data from this nationally-representative Canadian survey are presented here. The metabolites MEP, MnBP, MBzP, MCPP, MEHP, MEOHP and MEHHP were detected in >90% of Canadians while MMP, MCHP, MnOP and MiNP were detected in <20% of the Canadian population. Step-wise regression analyses were carried out to identify important predictors of volumetric concentrations (μg/L) of the metabolites in the general population. Individual multiple regression models with covariates age, sex, creatinine, fasting status, and the interaction terms age×creatinine, age×sex and fasting status×creatinine were constructed for MEP, MnBP, MBzP, MCPP, MEHP, MEOHP and MEHHP. The least square geometric mean (LSGM) estimates for volumetric concentration (μg/L) of the metabolites derived from respective regression models were used to assess the patterns in the metabolite concentrations among population sub-groups. The results indicate that children had significantly higher urinary concentrations of MnBP, MBzP, MEHP, MEHHP, MEOHP and MCPP than adolescents and adults. Moreover, MEP, MBzP, MnBP and MEOHP concentrations in females were significantly higher than in males. We observed that fasting status significantly affects the concentrations of MEHP, MEHHP, MEOHP, and MCPP metabolites analyzed in this study. Moreover, our results indicate that the sampling time could affect the DEHP metabolite concentrations in the general Canadian population.

Occurrence and profiles of phthalates in foodstuffs from China and their implications for human exposure

Phthalate esters are used in a wide variety of consumer products, and human exposure to this class of compounds is widespread. Nevertheless, studies on dietary exposure of humans to phthalates are limited. In this study, nine phthalate esters were analyzed in eight categories of foodstuffs (n = 78) collected from Harbin and Shanghai, China, in 2011. Dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), benzyl butyl phthalate (BzBP), and diethylhexyl phthalate (DEHP) were frequently detected in food samples. DEHP was the major compound found in most of the food samples, with concentrations that ranged from below the limit of quantification (LOQ) to 762 ng/g wet weight (wt). The concentrations of phthalates in food samples from China were comparable to concentrations reported for several other countries, but the profiles were different; DMP was found more frequently in Chinese foods than in foods from other countries. The estimated daily dietary intake of phthalates (EDIdiet) was calculated based on the concentrations measured and the daily ingestion rates of food items. The EDIdiet values for DMP, DEP, DIBP, DBP, BzBP, and DEHP (based on mean concentrations) were 0.092, 0.051, 0.505, 0.703, 0.022, and 1.60 μg/kg-bw/d, respectively, for Chinese adults. The EDIdiet values calculated for phthalates were below the reference doses suggested by the United States Environmental Protection Agency (EPA). Comparison of total daily intakes, reported previously based on a biomonitoring study, with the current dietary intake estimates suggests that diet is the main source of DEHP exposure in China. Nevertheless, diet accounted for only <10% of the total exposure to DMP, DEP, DBP, and DIBP, which suggested the existence of other sources of exposure to these phthalates.

Analysis of phthalates in food products and packaging materials sold on the Belgian market

Phthalates are organic lipophilic compounds that are principally used as plasticiser to increase the flexibility of plastic polymers. Other applications are a.o. the use of phthalates in printing inks and lacquers. Human exposure to phthalates mainly occurs via food ingestion and can induce adverse health effects. In this study, the presence of eight phthalate compounds--dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), benzylbutyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), dicyclohexyl phthalate (DCHP) and di-n-octyl phthalate (DnOP)--was investigated in 400 food products, divided over eleven groups, and packages sold on the Belgian market. For this purpose, suitable extraction techniques were developed and validated for four different matrices, namely high-fat foods, low-fat food products, aqueous-based beverages and packaging materials. The instrumental analysis was performed by means of gas chromatography-low resolution-mass spectrometry with electron impact ionisation (GC-EI-MS). A wide variety of phthalate concentrations was observed in the different groups. DEHP was found in the highest concentration in almost every group. Moreover, DEHP was the most abundant phthalate compound, followed by DiBP, DnBP and BBP. This survey is part of the PHTAL project, which is the first project that discusses phthalate contamination on the Belgian food market.

Children's exposure to Di(2-ethylhexyl)phthalate and dibutylphthalate plasticizers from school meals

Packed school meals for children 3-10 years old were studied to evaluate the levels of di(2-ethylhexyl)phthalate (DEHP) and di-n-butylphthalate (DBP) and the influence of the packaging process on meal contamination, and their contribution to daily intake was estimated. The packaging consisted of polyethylene-coated aluminum (PE/Al) dishes thermally welded by a polyethyleneterephthalate-coated aluminum (PET/Al) foil. Foodstuffs before processing were analyzed, too. Total meals before packaging and after packaging were collected. It was found that 92% of foodstuffs employed in meal preparation contained DEHP, and 76% of them DBP, at detectable levels. In cooked foods before packaging the DEHP median concentration levels varied from 111.4 to 154.8 ng/g ww and those of DBP between 32.5 and 59.5 ng/g ww. In packed meals the DEHP median values ranged from 127.0 to 253.3 ng/g ww, and DBP median values varied from 44.1 to 80.5 ng/g ww. The mean increases of median concentrations of DEHP in cooked foods before and after packaging were 113 and 125% for DBP. For nursery and primary school children DEHP intake via school meals can raise on average the respective EFSA TDI by 18 and 12% and that of DBP by 50 and 30%.

Modeling Human Exposure to Phthalate Esters: A Comparison of Indirect and Biomonitoring Estimation Methods

Humans are potentially exposed to phthalate esters (PEs) through ingestion, inhalation, and dermal contact. Studies quantifying exposure to PEs include "biomarker studies" and "indirect studies." Biomarker studies use measurements of PE metabolites in urine to back-calculate exposure to the parent diester, while indirect studies use the concentration of the PE in each medium of exposure and the rate of intake of that medium to quantify intake of the PE. In this review, exposure estimates from biomarker and indirect studies are compiled and compared for seven PEs to determine if there are regional differences and if there is a preferred approach. The indirect and biomarker methods generally agree with each other within an order of magnitude and discrepancies are explained by difficulties in accounting for use of consumer products, uncertainty concerning absorption, regional differences, and temporal changes. No single method is preferred for estimating intake of all PEs; it is suggested that biomarker estimates be used for low molecular weight PEs for which it is difficult to quantify all sources of exposure and either indirect or biomarker methods be used for higher molecular weight PEs. The indirect methods are useful in identifying sources of exposure while the biomarker methods quantify exposure.

Dietary intake is associated with phthalate body burden in a nationally representative sample

BACKGROUND

Phthalates are compounds that are used in a wide range of consumer products. However, the contribution of dietary intake to phthalate exposure has not been well defined.

OBJECTIVE

The objective of this study was to assess the contribution of different food types to phthalate exposure. Phthalates are chemicals of concern because of the high levels measured in people and the environment, as well as the demonstrated toxicity in animal studies and limited epidemiological studies. Previous research, although limited, has suggested that phthalates contaminate food in various countries.

METHODS

We conducted an exploratory analysis of data collected as part of the 2003-2004 National Health and Nutrition Examination Survey (NHANES). Associations between dietary intake (assessed by a 24-hr dietary recall) for a range of food types (meat, poultry, fish, fruit, vegetable, and dairy) and phthalate metabolites measured in urine were analyzed using multiple linear regression modeling.

RESULTS

We found that metabolites of di-(2-ethylhexyl) phthalate (DEHP) and high-molecular-weight phthalate metabolites were associated with the consumption of poultry. Monoethyl phthalate, the metabolite of diethyl phthalate (DEP), was associated with vegetable consumption, specifically tomato and potato consumption.

DISCUSSION

These results, combined with results from previous studies, suggest that diet is an important route of intake for phthalates. Further research is needed to determine the sources of food contamination with these toxic chemicals and to describe the levels of contamination of U.S. food in a large, representative U.S. sample.

Determination of phthalates in diet and bedding for experimental animals using gas chromatography-mass spectrometry

We have developed a gas chromatography-mass spectrometry method to measure five phthalates (dibutyl phthalate, butylbenzyl phthalate, di-2-ethylhexyl phthalate, diisooctyl phthalate, and diisononyl phthalate) in diets and beddings for experimental animals. The recoveries from diets and beddings spiked with five phthalates were 98.8%-148% with coefficients of variation of 0.4%-7.8% for diets and 94.7%-146% with coefficients of variation of 1.0%-5.0% for beddings. We analyzed commercial animal diets and beddings, and found that the levels of phthalates varied from sample to sample; the concentrations of five phthalates were 141-1,410 ng/g for diets and 20.5-7,560 ng/g for beddings.

Phthalate Esters in Foods: Sources, Occurrence, and Analytical Methods

  Phthalates are a group of diesters of ortho-phthalic acid (dialkyl or alkyl aryl esters of 1,2-benzenedicarboxylic acid). Higher-molecular-weight phthalates, such as di-2-ethylhexyl phthalate (DEHP), are primarily used as plasticizers to soften polyvinyl chloride (PVC) products, while the lower-molecular-weight phthalates, such as diethyl phthalate (DEP), di-n-butyl phthalate (DBP), and butyl benzyl phthalate (BBzP), are widely used as solvents to hold color and scent in various consumer and personal care products. Phthalates have become ubiquitous environmental contaminants due to volatilization and leaching from their widespread applications, and thus contamination of the environment has become another important source for phthalates in foods in addition to migration from packaging materials. Human exposure to phthalates has been an increased concern due to the findings from toxicology studies in animals. DEHP, one of the important and widely used phthalates, is a rodent liver carcinogen. DEHP, DBP, BBzP, and several phthalate metabolites, such as monobutyl phthalate, monobenzyl phthalate, and mono-(2-ethylhexyl) phthalate, are teratogenic in animals. Since foods are the major source of exposure to phthalates, information on levels of phthalates in foods is important for human exposure assessment. The objective of this review is to identify the knowledge gaps for future investigations by reviewing levels of a wide range of phthalates in a variety of foods, such as bottled water, soft drinks, infant formula, human milk, total diet foods, and others, migration of phthalates from various food-packaging materials, and traditional and new methodologies for the determination of phthalates in foods.

Pre-pubertal Di(2-ethylhexyl) Phthalate (DEHP) Exposure of Young Boars Did Not Affect SpermIn vitroPenetration Capacity of Homologous Oocytes Post-puberty

Di(2-ethylhexyl) phthalate (DEHP), a plastic softener used in polyvinylchloride (PVC) products (e.g., plastic bags and medical equipment), has been reported to have toxic effects on animal reproduction and is considered an environmental hazard based, mostly, on rodent studies. However, the doses used in these studies are often considerably higher than that presumed in human exposure. In the present study we used young boars as model animals to assess the effects of pre-pubertal DEHP exposure on the ability of spermatozoa to penetrate homologous oocytes in vitro. Eight pairs of cross-bred male boar siblings were used. One brother in each pair became, at random, the test animal exposed to DEHP per os, three times a week, from 3 to 7 weeks of age while the other acted as the control, i.e., placebo-exposed. Semen was collected and frozen between 8 and 9 months of age and stored until spermatozoa were evaluated for their ability to in vitro penetrate in vitro-matured homologous oocytes post-thaw. Both the penetration rate and the number of spermatozoa per oocyte were considered within expected ranges for frozen boar semen of good quality. Penetration rate did not significantly differ (p > 0.05) between the groups with DEHP-exposed: 50%; control: 59%, which could be owing to a large variation between boars, and between replicates. The number of spermatozoa in the ooplasm was low and similar (p > 0.05) between the groups with DEHP-exposed: 1.5 and the control: 1.7. Under the conditions of the present experiment, pre-pubertal exposure to DEHP does not seem to cause a deleterious effect on the in vitro fertilizing ability of frozen spermatozoa post-puberty.

Endocrine disrupters as obesogens

The recent dramatic rise in obesity rates is an alarming global health trend that consumes an ever increasing portion of health care budgets in Western countries. The root cause of obesity is thought to be a prolonged positive energy balance. Hence, the major focus of preventative programs for obesity has been to target overeating and inadequate physical exercise. Recent research implicates environmental risk factors, including nutrient quality, stress, fetal environment and pharmaceutical or chemical exposure as relevant contributing influences. Evidence points to endocrine disrupting chemicals that interfere with the body's adipose tissue biology, endocrine hormone systems or central hypothalamic-pituitary-adrenal axis as suspects in derailing the homeostatic mechanisms important to weight control. This review highlights recent advances in our understanding of the molecular targets and mechanisms of action for these compounds and areas of future research needed to evaluate the significance of their contribution to obesity.

Reproductive and developmental toxicity of phthalates

The purposes of this review are to (1) evaluate human and experimental evidence for adverse effects on reproduction and development in humans, produced by exposure to phthalates, and (2) identify knowledge gaps as for future studies. The widespread use of phthalates in consumer products leads to ubiquitous and constant exposure of humans to these chemicals. Phthalates were postulated to produce endocrine-disrupting effects in rodents, where fetal exposure to these compounds was found to induce developmental and reproductive toxicity. The adverse effects observed in rodent models raised concerns as to whether exposure to phthalates represents a potential health risk to humans. At present, di(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP), and butyl benzyl phthalate (BBP) have been demonstrated to produce reproductive and developmental toxicity; thus, this review focuses on these chemicals. For the general population, DEHP exposure is predominantly via food. The average concentrations of phthalates are highest in children and decrease with age. At present, DEHP exposures in the general population appear to be close to the tolerable daily intake (TDI), suggesting that at least some individuals exceed the TDI. In addition, specific high-risk groups exist with internal levels that are several orders of magnitude above average. Urinary metabolites used as biomarkers for the internal levels provide additional means to determine more specifically phthalate exposure levels in both general and high-risk populations. However, exposure data are not consistent and there are indications that secondary metabolites may be more accurate indicators of the internal exposure compared to primary metabolites. The present human toxicity data are not sufficient for evaluating the occurrence of reproductive effects following phthalate exposure in humans, based on existing relevant animal data. This is especially the case for data on female reproductive toxicity, which are scarce. Therefore, future research needs to focus on developmental and reproductive endpoints in humans. It should be noted that phthalates occur in mixtures but most toxicological information is based on single compounds. Thus, it is concluded that it is important to improve the knowledge of toxic interactions among the different chemicals and to develop measures for combined exposure to various groups of phthalates.

The internal exposure of Taiwanese to phthalate--an evidence of intensive use of plastic materials

Phthalates are widely used in industry and consumer products. Di-(2-ethylhexyl) phthalate (DEHP) and di-n-butylphthalate (DBP) show the greatest potency of reproductive toxicants among phthalates. The purposes of this study are to examine the migration level of phthalate from PVC films by simulating food handling and to reveal the body burden of phthalate for Taiwanese. In order to estimate a worst-case of phthalate migration, food was covered with polyvinyl chloride (PVC) films and then microwave heated. Results show that DEHP level in food increased significantly after heating for 3 min. Under the heating condition, the calculated intake of phthalate and the percentage of the tolerable daily intake (TDI, based on body weight of 60 kg) from eating one 400-g meal were 1705.6 microg and 92.2% for DEHP. Determination of urinary metabolites from 60 subjects reveals more than 90% of samples were detectable for mono-methyl phthalate (MMP), mono-butyl phthalate (MBP) and mono-ethylhexyl phthalate (MEHP). Notably, the median value of estimated daily intake of DEHP had reached 91.6% of TDI established by the European Union Scientific Committee for Toxicity, Ecotoxicity and the Environment (CSTEE) (1998). Thirty-seven percent of the study population exceeded the TDI and 85% exceeded the reference dose (RfD) of the US EPA. We conclude that the body burden of DEHP for Taiwanese reflects the intensives use of plastic materials in the region. The regulation of PVC for food preparation is necessary.

Environmental chemicals: from the environment to food, to breast milk, to the infant

Food is a source of exposure to many environmental chemicals found in human milk and other biological specimens. Ingestion of foods containing high amounts of animal fat is the main route of human exposure to lipophilic chemicals, such as persistent organic pollutants, which tend to bioaccumulate in the lipid compartment. Bioaccumulation results in increased exposure of these chemicals for humans, but particularly to breastfeeding infants, who are at the top of the food chain. The extent to which food contributes to a person's overall exposure depends on individual dietary habits and the concentrations of chemical residues in the food. These, in turn, are affected by (1) application methods, (2) properties and amounts of the chemical, and (3) preparation, handling, and the properties of the food. Once the food is ingested by the lactating woman, the chemical's pharmacokinetics and the transport mechanisms producing the movement of solutes across mammary alveolar cells determine the passage of chemicals from the blood to the milk. Thus, several factors affect the presence in human milk of environmental chemicals from dietary sources.

Intake of phthalates and di(2-ethylhexyl)adipate: results of the Integrated Exposure Assessment Survey based on duplicate diet samples and biomonitoring data

Phthalates are ubiquitous environmental chemicals with potential detrimental health effects. The purpose of our study was to quantify dietary intake of phthalates and of DEHA (Di-ethylhexyl adipate) using duplicate diet samples and to compare these data with the calculated data based on urinary levels of primary and secondary phthalate metabolites. 27 female and 23 male healthy subjects aged 14-60 years collected daily duplicate diet samples over 7 consecutive days. Overall, 11 phthalates were measured in the duplicates by GC/MS and LC/MS methods. Urinary levels of primary and secondary phthalate metabolites are also available. The median (95th percentile) daily intake via food was 2.4 (4.0) microg/kg b.w. (Di-2-ethylhexyl phthalate, DEHP), 0.3 (1.4) microg/kg b.w. (Di-n-butyl phthalate, DnBP), 0.6 (2.1) microg/kg b.w. (Di-isobutyl phthalate, DiBP) and 0.7 (2.2) microg/kg b.w. for DEHA. MEPH (Mono-2-ethylhexyl phthalate) was detectable only in minor concentrations in the samples, thus conversion of DEHP to MEHP and dietary intake of MEHP were negligible. When comparing back-calculated intake data of the DEHP metabolites with dietary DEHP intake from the day before significant correlations were observed for most of the metabolites. No correlation was found for DnBP and only a weak but significant correlation for DiBP. The median and 95th percentile daily dietary intake of all target analytes did not exceed the recommended tolerable daily intake. Our data indicated that food was the predominant intake source of DEHP, whilst other sources considerably contributed to the daily intake of DnBP and DiBP in an adult population.

Phthalates: Toxicology and exposure

Phthalates are used as plasticizers in PVC plastics. As the phthalate plasticizers are not chemically bound to PVC, they can leach, migrate or evaporate into indoor air and atmosphere, foodstuff, other materials, etc. Consumer products containing phthalates can result in human exposure through direct contact and use, indirectly through leaching into other products, or general environmental contamination. Humans are exposed through ingestion, inhalation, and dermal exposure during their whole lifetime, including intrauterine development. This paper presents an overview on current risk assessments done by expert panels as well as on exposure assessment data, based on ambient and on current human biomonitoring results. Some phthalates are reproductive and developmental toxicants in animals and suspected endocrine disruptors in humans. Exposure assessment via modelling ambient data give hints that the exposure of children to phthalates exceeds that in adults. Current human biomonitoring data prove that the tolerable intake of children is exceeded to a considerable degree, in some instances up to 20-fold. Very high exposures to phthalates can occur via medical treatment, i.e. via use of medical devices containing DEHP or medicaments containing DBP phthalate in their coating. Because of their chemical properties exposure to phthalates does not result in bioaccumulation. However, health concern is raised regarding the developmental and/or reproductive toxicity of phthalates, even in environmental concentrations.

Quantitative identification of unknown exposure pathways of phthalates based on measuring their metabolites in human urine

Humans are exposed to ubiquitous phthalates via multiple pathways. Exposures to phthalates have been estimated in some previous risk assessments in Japan based on point-of-contact measurement or scenario evaluation approaches. While the Japanese national government has regulated the use of di(2-ethylhexyl)phthalate (DEHP) and excluded several other phthalates from its regulation based on some of them, it is unclear whether such past exposure assessment studies fully assessed total human exposure to phthalates. In the present study, we measured their urinary metabolites, which show direct evidence of human exposure to phthalates. We recruited voluntary participants (N = 36) who agreed to donate urine samples, and measured the urinary concentrations of phthalate metabolites using enzymatic deconjugation, solid-phase extraction, and high-performance liquid-chromatography isotope-dilution tandem mass spectrometry. We then derived the daily intakes of their respective phthalates based on steady state assumption and finally compared them with the corresponding estimated daily intakes of each phthalate via diet and air derived from previous exposure or risk assessments in Japan. These comparisons showed that exposures to dimethyl phthalate, diethyl phthalate, and di-n-butyl phthalate via diet and air accounted for less than half of their respective total exposures. On the other hand, it appears that dietary intake was more predictive for the total exposure to n-butyl-benzyl phthalate and DEHP. The probabilities that the log normal distribution of each phthalate daily intake estimated from the present study exceeds the corresponding tolerable daily intake were estimated to be less than 10(-4).

Early pre-pubertal exposure to low-dose oral di(2-ethylhexyl) phthalate does not affect sperm plasma membrane stability, acrosomal integrity or chromatin structure in the post-pubertal boar

This study aimed to determine whether pre-pubertal exposure in boars to di(2-ethylhexyl) phthalate (DEHP), a plasticizer reported to have toxic effects on rodent reproduction, would affect the sperm ability to undergo capacitation and acrosome reaction (AR) in vitro or give rise to a higher degree of chromatin instability associated with acid-induced denaturation. Spermatozoa were collected from 16 boars (n=8/group) 8-9 months of age, exposed to 300mg/kg body weight of DEHP or placebo per os three times a week, from 3 to 7 weeks of age. The spermatozoa were cryopreserved and examined post-thaw by flow cytometry for their ability to capacitate in vitro when exposed to the effector bicarbonate and to acrosome-react when exposed to calcium ionophores, using the lipid stain Merocyanine-540 (m-540), and peanut agglutinin-fluorescein isothiocyanate, respectively, as probes. The ability of the DNA to sustain denaturation in vitro was tested using a sperm chromatin structure assay (SCSA). No significant differences between the DEHP-exposed group and controls were found for any of the sperm attributes examined. Frozen-thawed spermatozoa showed similar rates of non-capacitated cells between groups, and were capacitated at similar rates. Rates of induced ARs were also similar. Values of DNA denaturation were low and showed no differences between groups. In conclusion, pre-pubertal exposure to DEHP does not seem, under the conditions of the present experiment, to affect the ability of frozen-thawed spermatozoa collected post-puberty to capacitate or acrosome-react (the main requisites for fertilization) or to present damage in their nuclear genome.

Oestrogenicity of paper and cardboard extracts used as food containers

Bisphenol-A (BPA), dibutyl phthalate (DBP), and di-2-ethylhexyl phthalate (DEHP), which are common chemical residues in food-packaging materials, were investigated in paper and cardboard containers used for take-away food. The oestrogenicity of aqueous extracts was tested in E-Screen bioassay and analysis carried out by high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC/MS). Oestrogenicity was demonstrated in 90% of extracts (geometric mean [GM] = 11.97 pM oestradiol equivalents g(-1)). DEHP, DBP, and BPA (GM = 341.74, 37.59, and 2.38 ng g(-1) of material) were present in 77.50, 67.50, and 47.50% of samples, respectively. In bivariate analyses, no significant association was found between the levels of these chemicals and oestrogenicity in cardboard/paper extracts. A close-to-significant association was found between oestrogenicity and DBP (beta = 1.25; p = 0.06) in paper extracts, which reached statistical significance in multivariate analysis (beta = 1.61; p = 0.03). Paper and cardboard used in food packaging may contribute to the inadvertent exposure of consumers to endocrine-disrupting chemicals.

Estrogenic potency of food-packaging-associated plasticizers and antioxidants as detected in ERalpha and ERbeta reporter gene cell lines

This study presents the estrogenic potency of 21 food-packaging-associated compounds determined for the first time, using two transfected U2-OS (human osteoblasts devoid of endogenous estrogen receptors) estrogen receptor (ER) alpha and beta cell lines. Six plasticizers and three antioxidants were slightly estrogenic in the ERalpha cells. The model compounds bisphenol A and nonylphenol, one plasticizer [tris(2-ethylhexyl)trimellitate (TEHTM)], and two antioxidants (propyl gallate and butylated hydroxyanisole) were estrogenic in both ERalpha and ERbeta cells. Compared to estradiol (E2), these compounds appeared to be relatively more estrogenic in the ERbeta cells than in the ERalpha cells. Three sorbitol-based plasticizers activated neither ERalpha nor ERbeta and may be good replacements of existing plasticizers. All responses were additive with the response of E2. This indicates that they may contribute to the total effects of the pool of estrogenic compounds humans are exposed to. The estrogenic potencies of these compounds, together with the suggested beneficial effect of ERbeta-mediated responses and adverse ERalpha-mediated effects, support the importance of detecting characteristics for ERalpha and ERbeta response separately in independent models, as done in the present study.

Determination of phthalates in milk and milk products by liquid chromatography/tandem mass spectrometry

A liquid chromatographic/tandem mass spectrometric method using pneumatically assisted electrospray ionisation (LC/ESI-MS/MS) was developed for determination of dibutyl phthalate (DBP), benzyl butyl phthalate (BBP), di-2-ethylhexyl phthalate (DEHP), di-'isononyl' phthalate (DINP) and di-'isodecyl' phthalate (DIDP) in milk and milk products including infant formulas. The phthalates were extracted by a mixture of tert-butyl methyl ether and hexane from liquid samples. DBP, BBP and DEHP were removed from fats by liquid/liquid extraction into acetonitrile while DINP and DIDP were cleaned up on deactivated silica. The phthalates were detected in positive ion mode after separation on a reversed-phase C5 analytical column. Two transition products were monitored for each compound. The detection limits related to the transition products of lowest abundance were in the range 5-9 microg/kg.

Etiology of Crohn’s disease: Do certain food additives cause intestinal inflammation by molecular mimicry of mycobacterial lipids?

Crohn's disease is a chronic granulomatous inflammation of the gastrointestinal tract which was first described in the beginning of the 20th century. The histological similarity with intestinal tuberculosis has led to the assumption of an involvement of mycobacteria and mycobacterial antigens, respectively, in the etiology. A major defense mechanism against mycobacterial lipid antigens is the CD1 system which includes CD1 molecules for antigen presentation and natural killer T cells for recognition and subsequent production of cytokines like interferon-gamma and tumour necrosis factor-alpha. These cytokines promote granulomatous transformation. Various food additives, especially emulsifiants, thickeners, surface-finishing agents and contaminants like plasticizers share structural domains with mycobacterial lipids. It is therefore hypothesized, that these compounds are able to stimulate by molecular mimicry the CD1 system in the gastrointestinal mucosa and to trigger the pro-inflammatory cytokine cascade. The understanding of Crohn's disease as a CD1-mediated delayed-type hypersensitivity to certain food additives would lead to strong emphasis on a dietary treatment. Related aspects of pathology, physiology and epidemiology of Crohn's disease are presented.

Exposure to phthalate esters from indoor environment

Phthalate esters and phosphate esters in samples of indoor air from 27 houses in the Tokyo Metropolitan area were quantified using gas chromatograph/mass spectrometer and gas chromatograph/flame photometric detector after adsorption on to charcoal and solvent extraction. The median concentrations of diethyl phthalate, dibutyl phthalate (DBP), butylbenzyl phthalate, dicyclohexyl phthalate and diethylhexyl phthalate were 0.10, 0.39, 0.01, 0.07 and 0.11 microg/m(3), respectively. The median concentrations of tributyl phosphate, tris(2-chloroethyl) phosphate, triphenyl phosphate and tris(2-butoxyethyl) phosphate were less than 0.001 microg/m(3). DBP was detected at the highest concentration (6.18 microg/m(3)) in a new residential housing. This research indicated that exposure to phthalate esters through inhalation of air from the indoor environment is as important as dietary intake of phthalate esters, and can contribute to daily intake to a much greater extent than has been assumed hitherto.

Plasticizers, infant nutrition and reproductive health

Since the 1930s, plasticizers have been used to impart flexibility to an otherwise rigid polyvinylchloride (PVC). Di-(2-ethylhexyl)-phthalate (DEHP) is the most widely used plasticizer in PVC formulations. However, DEHP leaks out from PVC items with time and use and consequently it is an ubiquitous environmental contaminant. To date, very little is known about the actual extent of DEHP exposure in infants, who are believed to be the most sensitive population, as they may be exposed to several different sources (breast milk, infant formula, baby food, indoor air, and by dermal and oral exposure via indoor dust containing DEHP) since early in life and since differences in DEHP pharmacokinetics and metabolism between children and adults have been well documented. Little information exists on DEHP dietary exposure, believed to represent a major source and orally administered DEHP is converted more rapidly to MEHP than other routes of exposure. Although DEHP has been shown to induce toxicity in experimental animals, a limited but suggestive human exposure data causes a serious concern that an early in life DEHP exposure may adversely affect male reproductive tract development. Here, we report a review on dietary phthalate exposure in babies.