A vision for safer food contact materials: Public health concerns as drivers for improved testing

Evidence for widespread human exposure to food contact chemicals

BACKGROUND

Over 1800 food contact chemicals (FCCs) are known to migrate from food contact articles used to store, process, package, and serve foodstuffs. Many of these FCCs have hazard properties of concern, and still others have never been tested for toxicity. Humans are known to be exposed to FCCs via foods, but the full extent of human exposure to all FCCs is unknown.

OBJECTIVE

To close this important knowledge gap, we conducted a systematic overview of FCCs that have been monitored and detected in human biomonitoring studies according to a previously published protocol.

METHODS

We first compared the more than 14,000 known FCCs to five biomonitoring programs and three metabolome/exposome databases. In a second step, we prioritized FCCs that have been frequently detected in food contact materials and systematically mapped the available evidence for their presence in humans.

RESULTS

For 25% of the known FCCs (3601), we found evidence for their presence in humans. This includes 194 FCCs from human biomonitoring programs, with 80 of these having hazard properties of high concern. Of the 3528 FCCs included in metabolome/exposome databases, most are from the Blood Exposome Database. We found evidence for the presence in humans for 63 of the 175 prioritized FCCs included in the systematic evidence map, and 59 of the prioritized FCCs lack hazard data.

SIGNIFICANCE

Notwithstanding that there are also other sources of exposure for many FCCs, these data will help to prioritize FCCs of concern by linking information on migration and biomonitoring. Our results on FCCs monitored in humans are available as an interactive dashboard (FCChumon) to enable policymakers, public health researchers, and food industry decision-makers to make food contact materials and articles safer, reduce human exposure to hazardous FCCs and improve public health.

IMPACT STATEMENT

We present systematically compiled evidence on human exposure to 3601 food contact chemicals (FCCs) and highlight FCCs that are of concern because of their known hazard properties. Further, we identify relevant data gaps for FCCs found in food contact materials and foods. This article improves the understanding of food contact materials' contribution to chemical exposure for the human population and highlights opportunities for improving public health.

Health impacts of exposure to synthetic chemicals in food

Humans are widely exposed to synthetic chemicals, especially via food. The types of chemical contaminants in food (including food contact chemicals) are diverse, and many of these are known to be hazardous, with mounting evidence that some contribute to noncommunicable diseases. The increasing consumption of ultra-processed foods, which contain synthetic chemicals, also contributes to adverse health. If the chemical contamination of foods were better characterized, then this issue would likely receive more attention as an important opportunity for disease prevention. In this Review, we discuss types and sources of synthetic food contaminants, focusing on food contact chemicals and their presence in ultra-processed foods. We outline future research needs and highlight possible responses at different food system levels. A sustainable transition of the food system must address the health impacts of synthetic chemicals in food; we discuss existing solutions that do justice to the complexity of the issue while avoiding regrettable substitutions and rebound effects.

Food Packaging and Chemical Migration: A Food Safety Perspective

Packaging has become an essential component of food production and distribution. It plays a vital role in preserving food quality and safety, while also helping to reduce food waste. However, the widespread use of packaging has led to increased chemical migration, posing significant risks to food safety and public health. Migration occurs when low molecular weight compounds from packaging materials, printing inks, or adhesives transfer to food under certain conditions, potentially introducing harmful substances. This contamination can degrade food quality through unwanted changes and expose consumers to serious health risks, highlighting the need for stringent controls. This review examines various packaging materials, explores the factors influencing the migration of chemical substances from packaging into food, compiles data on the presence of migrants in foods, identifies those posing risks to public health, and underlines measures to minimize migration from a food safety perspective.

Degree of food processing and serum poly- and perfluoroalkyl substance concentrations in the US National Health and Nutrition Examination Survey, 2003-2018

BACKGROUND

Ultra-processed foods account for >50% of total energy consumed among U.S. individuals and may be a source of poly- and perfluoroalkyl substances (PFAS) exposure - chemicals linked with cancer/cardiometabolic disorders.

OBJECTIVE

To evaluate associations between degree of food processing and PFAS exposure.

METHODS

Serum concentrations of seven PFAS were analyzed in 11,530 individuals ≥12-years-old from the U.S. National Health and Nutrition Examination Survey (2003-2018). We averaged responses from two 24-h dietary recalls to calculate relative energy intakes of unprocessed/minimally processed foods, processed culinary ingredients, processed foods, and ultra-processed foods using the Nova food classification system. We estimated percent differences in concentrations (β; PFAS with ≥70% detection) or odds ratios of detection (OR; PFAS with <70% detection) using linear or logistic regression, respectively. We explored associations stratified by cycle, life stage, sex, body mass index, race/ethnicity, and poverty/income ratio.

RESULTS

Each 10% increase in ultra-processed food intake was associated with higher serum perfluorohexanesulfonic acid (PFHxS; β: 1.40; 95%CI: -0.12, 2.94), but lower perfluorodecanoic acid (PFDA; β: -4.41; 95%CI: -5.55, -3.26) and perfluoroundecanoic acid (PFUnDA; OR: 0.82; 95%CI: 0.79, 0.86) concentrations. Positive associations between ultra-processed foods and PFHxS were driven by adolescents and under-/normal weight individuals. Additionally, each 10% increase in unprocessed/minimally processed food intake was associated with lower perfluorooctanoic acid (PFOA; β: -1.10; 95%CI: -2.38, 0.20) and PFHxS (β: -1.50; 95%CI: -3.03, 0.06), but higher perfluorononanoic acid (PFNA; β: 1.71; 95%CI: 0.24, 3.21), PFDA (β: 5.33; 95%CI: 3.78, 6.90), and PFUnDA (OR: 1.22; 95%CI: 1.16, 1.27). Positive and negative associations of unprocessed/minimally processed foods and ultra-processed foods, respectively, with PFDA and PFUnDA were strongest in recent survey cycles, males, and non-Hispanic Asians.

SIGNIFICANCE

Unprocessed/minimally processed foods, more than ultra-processed, were associated with serum PFAS concentrations. Efforts should focus on eliminating PFAS from multiple parts of the food chain.

Rapid Generation of Microplastics and Plastic-Derived Dissolved Organic Matter from Food Packaging Films under Simulated Aging Conditions

In this study, we show that low-density polyethylene films, a prevalent choice for food packaging in everyday life, generated high numbers of microplastics (MPs) and hundreds to thousands of plastic-derived dissolved organic matter (DOM) substances under simulated food preparation and storage conditions. Specifically, the plastic film generated 66-2034 MPs/cm2 (size range 10-5000 μm) under simulated aging conditions involving microwave irradiation, heating, steaming, UV irradiation, refrigeration, freezing, and freeze-thaw cycling alongside contact with water, which were 15-453 times that of the control (plastic film immersed in water without aging). We also noticed a substantial release of plastic-derived DOM. Using ultrahigh-resolution mass spectrometry, we identified 321-1414 analytes with molecular weights ranging from 200 to 800 Da, representing plastic-derived DOM containing C, H, and O. The DOM substances included both degradation products of polyethylene (including oxidized forms of oligomers) and toxic plastic additives. Interestingly, although no apparent oxidation was observed for the plastic film under aging conditions, plastic-derived DOM was more oxidized (average O/C increased by 27-46%) following aging with a higher state of carbon saturation and higher polarity. These findings highlight the future need to assess risks associated with MP and DOM release from plastic wraps.

A toxic relationship: ultra-processed foods & plastics

BACKGROUND

Among the crises engulfing the world is the symbiotic rise of ultra-processed foods (UPFs) and plastics. Together, this co-dependent duo generates substantial profits for agri-food and petrochemical industries at high costs for people and planet. Cheap, lightweight and highly functional, plastics have ideal properties that enable business models to create demand for low-cost, mass-produced and hyper-palatable UPFs among populations worldwide, hungry, or not. Evidence linking UPF consumption to deterioration in diet quality and higher risk of chronic diseases is well-established and growing rapidly. At the same time, the issue of plastic food contact chemicals (FCCs) is receiving increasing attention among the human health community, as is the generation and dispersion of micro- and nanoplastics.

MAIN BODY

In this commentary, we explore how the lifecycles and shared economic benefits of UPFs and plastics interact to co-produce a range of direct and indirect harms. We caution that the chemical dimension of these harms is underappreciated, with thousands of plastic FCCs known to migrate into foodstuffs. Some of these are hazardous and have been detected in humans and the broader environment, while many are yet to be adequately tested. We question whether policies on both UPF and plastic chemicals are fit for purpose when production and consumption of these products is adding to the chronic chemical exposures that plausibly contribute to the increasing global burden of non-communicable diseases.

CONCLUSIONS

In the context of ongoing negotiations for a legally binding global treaty to end plastics pollution, and rapidly growing concern about the burgeoning share of UPFs in diets worldwide, we ask: What steps are needed to call time on this toxic relationship?

Potential mammary carcinogens used in food contact articles: implications for policy, enforcement, and prevention

Many nations have food contact material (FCM) legislation purporting to protect citizens from hazardous chemicals, often specifically by regulating genotoxic carcinogens. Despite such regulations, cancers that are associated with harmful chemical exposures are highly prevalent, especially breast cancer. Using the novel Key Characteristics of Toxicants framework, Kay et al. found 921 substances that are potential mammary carcinogens. By comparing Kay et al.'s chemicals list with our own Database on migrating and extractable food contact chemicals (FCCmigex), we found that 189 (21%) of the potential mammary carcinogens have been measured in FCMs. When limiting these results to migration studies published in 2020-2022, 76 potential mammary carcinogens have been detected to migrate from FCMs sold in markets across the globe, under realistic conditions of use. This implies that chronic exposure of the entire population to potential mammary carcinogens from FCMs is the norm and highlights an important, but currently underappreciated opportunity for prevention. Reducing population-wide exposure to potential mammary carcinogens can be achieved by science-based policy amendments addressing the assessment and management of food contact chemicals.

Polyfluoroalkyl-Substances Detection in Junk Food Packing Materials Using Various Analytical Methods: A Review

Per- and polyfluoroalkyl substances (PFAS) are unseen, dangerous organic compounds that can cause major health disorders. PFASs have been categorized as persistent, bioaccumulative, and toxic (PBT). This review provides knowledge about the PFASs present in junk food packaging materials, which can migrate into the food. Different types of samples were analyzed using the analytical methods. The most preferred method of extraction is ultrasonic-assisted extraction (UAE). It summarizes the analytical approaches of PFASs. The results of numerous studies show that perfluorooctanoic acid is the most often detected compound with high concentrations. The European Food Safety Authority (EFSA) announced that the tolerable weekly intake (TWI) of PFASs is 4.4 ng/kg. The US Environmental Protection Agency (EPA) has announced the limit for perfluorobutane sulfonic acid due to its toxicity level. These compounds have potential effects on both people's health and the biosphere. PFAS usage has to stop in the industries for a better future.

Aged fragmented-polypropylene microplastics induced ageing statues-dependent bioenergetic imbalance and reductive stress: In vivo and liver organoids-based in vitro study

Ageing is a nature process of microplastics that occurrs daily, and human beings are inevitably exposed to aged microplastics. However, a systematic understanding of ageing status and its toxic effect is currently still lacking. In this study, plastic cup lids-originated polypropylene (PP) microplastics were UV-photoaged until the carbonyl index (CI), a canonical indicator for plastic ageing, achieved 0.08, 0.17, 0.22 and 0.28. The adverse hepatic effect of these aged PPs (aPPs) was evaluated in Balb/c mice (75 ng/mL water, about 200 particles/day) and human-originated liver organoids (LOs, 50 particles/mL, ranged from 5.94 to 13.15 ng/mL) at low-dose equivalent to human exposure level. Low-dose of aged PP could induce hepatic reductive stress both in vitro and in vivo, by elevating the NADH/NAD+ratio in a CI-dependent manner, together with hepatoxicity (indicated by increased AST secretion and cytotoxicity), and disrupted the genes encoding the nutrients transporters and NADH subunits accompanied by the restricted ATP supply, declined mitochondrial membrane potential and mitochondrial complexI/IV activities, without significant increase in MDA levels in the liver. These changes in the liver disrupted systematic metabolism, representing a circulatory panel of increases in the lactate, triglyceride, Fgf21 levels, and decreases in the pyruvate level, linked the reductive stress to the declined body weight gain but elevated hepatic NADH contents following aPPs exposure. Additionally, assessing by the LOs, it was found that digestion drastically accelerated the ageing of aPPs and worsen the energy supply upon mitochondria, representing a "scattergun effect" induced by the formation of micro- and nano-plastics mixture toward NADH/NAD+imbalance.

Potential for Glove Risk Amplification via Direct Physical, Chemical, and Microbiological Contamination

This review focuses on the potential direct physical, chemical, and microbiological contamination from disposable gloves when utilized in food environments, inclusive of the risks posed to food products as well as worker safety. Unrecognized problems endemic to glove manufacturing were magnified during the COVID-19 pandemic due to high demand, increased focus on PPE performance, availability, supply chain instability, and labor shortages. Multiple evidence-based reports of contamination, toxicity, illness, deaths, and related regulatory action linked to contaminated gloves in food and healthcare have highlighted problems indicative of systemic glove industry shortcomings. The glove manufacturing process was diagramed with sources and pathways of contamination identified, indicating weak points with documented occurrences detailed. Numerous unsafe ingredients can introduce chemical contaminants, potentially posing risks to food and to glove users. Microbial hazards present significant challenges to overall glove safety as contaminants appear to be introduced via polluted water sources or flawed glove manufacturing processes, resulting in increased risks within food and healthcare environments. Frank and opportunistic pathogens along with food spoilage organisms can be introduced to foods and wearers. When the sources and pathways of glove-borne contamination were explored, it was found that physical failures play a pivotal role in the release of sweat build-up, liquefaction of chemical residues, and incubation of microbial contaminants from hands and gloves. Thus, with glove physical integrity issues, including punctures in new, unused gloves that can develop into significant rips and tears, not only can direct physical food contamination occur but also chemical and microbiological contamination can find their way into food. Enhanced regulatory requirements for Acceptable Quality Limits of food-grade gloves, and the establishment of appropriate bioburden standards would enhance safety in food applications. Based on the information provided, together with a false sense of security associated with glove use, the unconditional belief in glove chemical and microbiological purity may be unfounded.

Beyond the Nucleus: Plastic Chemicals Activate G Protein-Coupled Receptors

G protein-coupled receptors (GPCRs) are central mediators of cell signaling and physiological function. Despite their biological significance, GPCRs have not been widely studied in the field of toxicology. Herein, we investigated these receptors as novel targets of plastic chemicals using a high-throughput drug screening assay with 126 human non-olfactory GPCRs. In a first-pass screen, we tested the activity of triphenol phosphate, bisphenol A, and diethyl phthalate, as well as three real-world mixtures of chemicals extracted from plastic food packaging covering all major polymer types. We found 11 GPCR-chemical interactions, of which the chemical mixtures exhibited the most robust activity at adenosine receptor 1 (ADORA1) and melatonin receptor 1 (MTNR1A). We further confirm that polyvinyl chloride and polyurethane products contain ADORA1 or MTNRA1 agonists using a confirmatory secondary screen and pharmacological knockdown experiments. Finally, an analysis of the associated gene ontology terms suggests that ADORA1 and MTNR1A activation may be linked to downstream effects on circadian and metabolic processes. This work highlights that signaling disruption caused by plastic chemicals is broader than that previously believed and demonstrates the relevance of nongenomic pathways, which have, thus far, remained unexplored.