Phthalates: Relationships between Air, Dust, Electronic Devices, and Hands with Implications for Exposure

An automated liquid-liquid extraction platform for high-throughput sample preparation of urinary phthalate metabolites in human biomonitoring

Automated sample preparation reduces variation caused by human factors and improves efficiency, throughput, and reliability, making it especially important in large-scale epidemiological biomonitoring applications. In this study, we demonstrated an automated liquid-liquid extraction platform that streamlines sample preparation for human biomonitoring of urinary phthalate metabolites. This platform integrates temperature-controlled enzymatic hydrolysis, adds extraction solvents, conducts shaking extraction, performs centrifugal separation, and transfers liquids. We optimized extraction solvents for liquid-liquid extraction of urinary phthalate metabolites and compared the extraction efficiency between manual and automated methods. The analytical performance of the platform was validated and compared with those obtained by manual liquid-liquid extraction and solid-phase extraction methods. We applied the automated liquid-liquid platform for determining urinary phthalate metabolites in the human biomonitoring of 232 health participants and evaluated their association with oxidative stress levels. Urinary phthalate metabolite concentrations showed a clear declining trend with increasing age. Males had significantly higher total urinary concentrations of phthalate metabolites than females. Monobutyl phthalate was the dominant metabolite in urine samples, followed by mono-isobutyl phthalate and monoethyl phthalate, with minor gender differences observed among individual metabolites. Trend tests and Bayesian Kernel Machine Regression analysis showed a significant positive association between urinary phthalate metabolites and the oxidative stress markers 8-hydroxyguanosine and 8-hydroxy-2'-deoxyguanosine, and monobutyl phthalate was identified as the most significant metabolite for the elevated 8-hydroxy-2'-deoxyguanosine levels. The automated liquid-liquid extraction platform exhibited high efficiency and reliability in preparing urinary samples for phthalate metabolite analysis, showing great promise in large-scale sample preparation of human biomonitoring applications.

Sex- and trimester-specific impact of gestational co-exposure to organophosphate esters and phthalates on insulin action among preschoolers: Findings from the Ma'anshan birth cohort

INTRODUCTION

Prenatal exposure to organophosphate esters (OPEs) and phthalic acid esters (PAEs) is ubiquitous among pregnant individuals. However, research exploring the relationship between prenatal co-exposure to OPEs and PAEs and childhood insulin function remains limited.

METHODS

In this study, utilizing data from 2,246 maternal-fetal dyads in the Ma'anshan Birth Cohort, associations between co-exposure to OPEs and PAEs and insulin action were analyzed. Repeated measures of tris (2-chloroethyl) phosphate, six OPE metabolites, and seven PAE metabolites were collected from maternal urine. Homeostasis model assessment of insulin resistance (HOMA-IR) and the insulin action index (IAI) served as outcome measures. After adjusting for potential confounders, the effects of repeated exposure on insulin action were evaluated using generalized estimating equations, while mixture effects were assessed through BayesianKernel Machine Regression and Quantile-Based G-Computation.

RESULTS

The average age of the children at the time of the study was 5.33 years. Repeated measures analysis revealed that prenatal exposure to MEP was positively associated with increased HOMA-IR (β, 0.027; 95 % CI: 0.002, 0.053), while IAI was inversely correlated with rising MEP levels (β, 0.025; 95 % CI: -0.046, -0.004) and MEHHP exposure (β, -0.128; 95 % CI: -0.218, -0.037). Mixed exposure modeling further indicated that co-exposure to OPEs and PAEs was positively linked to HOMA-IR (β, 0.058; 95 % CI: 0.001, 0.114) and negatively correlated with IAI (β, -0.054; 95 % CI: -0.097, -0.010), with stronger effects observed during the second trimester. Notably, the association was more pronounced in female children compared to males.

CONCLUSIONS

This study provides the first epidemiological evidence highlighting the pregnancy- and sex-specific links between prenatal co-exposure to OPEs and PAEs and childhood insulin action.

Colonization of phthalate-degrading endophytic bacterial consortium altered bacterial community and enzyme activity in plants

Phthalates (PAEs) are widely distributed hazardous organic compounds that pose threats to ecosystems and human health. Endophytic bacteria can effectively eliminate PAEs contamination risk. However, limited information is available regarding the impact of endophytic bacterial colonization on bacterial communities within plants. In this study, the endophytic bacterial consortium EN was colonized in lettuce by seed soaking, root irrigation, leaf spraying, and combined spraying-irrigation, resulting in a marked improvement in plant growth. The findings revealed that consortium EN colonization through combined spraying-irrigation exhibited superior degradation capability with 40.54% PAEs removal from soil. Meanwhile, the residual PAEs in lettuce decreased by 94.05% compared with the uninoculated treatment. High-throughput sequencing analysis indicated that colonization of consortium EN altered the bacterial community in lettuce. Specifically, the relative abundance of the dominant genus Pseudomonas was significantly higher than that in the uninoculated control (P < 0.01). Additionally, colonization enhanced the activities of peroxidase and catalase in lettuce, thereby improving plant resistance. This work offers a theoretical foundation for comprehending the mechanism underlying the bioremediation of PAEs contamination by endophytic bacteria in soil-plant system.

Infants exposure to chemicals in diapers: A review and perspective

Diapers are a staple care product for infants, yet concerns persist regarding the potential risks posed by dermal exposure to chemicals through their usage. This review provides a comprehensive summary of reported chemicals, highlighting the frequent detection of polychlorodibenzo-p-dioxins (PCDDs), phthalates (PAEs), volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), bisphenols (BPs), organotins, and heavy metals. Disposable diapers commonly exhibit higher concentrations of VOCs, PAEs, BPs, and heavy metals than other chemicals. Our estimation reveals formaldehyde as posing the highest dermal exposure dose, reaching up to 0.018 mg/kg bw/day. Conversely, perfluorooctanoic acid (PFOA) exhibits lower exposure, but its non-cancer hazard quotient (0.062) is the highest. In most scenarios, the risk of chemical exposure through diapers for infants is deemed acceptable, while the risk is higher under some extreme exposure scenarios. Using the cancer slope factor recently suggested by U.S. EPA, the cancer risk in diapers raised by PFOA is 5.5 × 10-5. It should be noted that our estimation is approximately 1000-10,000 folds lower than some previous estimations. The high uncertainties associated with exposure and risk estimations are primarily raised by unclear parameters related to chemical migration coefficients, absorption factors, concentrations, and toxicity data for skin exposure, which requires research attention in future. Besides that, future research endeavors should prioritize the identification of potential toxic chemicals and the development of hygiene guidelines and standards.

Management of phthalates in Canada and beyond: can we do better to protect human health?

Ortho-phthalates (herein referred to as phthalates) are synthetic chemicals used in thousands of different everyday products and materials. Nearly ubiquitous environmental exposure is reflected by phthalate metabolites in the urine of almost all Canadians. However, phthalate exposure tends to be higher amongst people of low socioeconomic status and ethnic minorities. Substantial evidence shows that certain phthalates cause harm to human health, particularly developing fetuses and children. Governments vary in their approach to assessing and managing risks associated with phthalates. Canada continues to take a more permissive stance on phthalate regulations compared to the EU and some US states. We argue that the recent Canadian national risk assessment on phthalates does not appropriately reflect the growing evidence demonstrating harm to human health from phthalate exposure and does not adequately consider the evidence showing higher exposures faced by vulnerable populations. Canadians would benefit from adopting a more stringent regulatory approach to phthalates. Specifically, Canada should expand phthalate restrictions to apply to all consumer products, implement sunset dates toward eliminating the use of existing phthalates, and mandate publicly available evidence of no harm for phthalate alternatives. Canadian alignment on phthalate regulations with the EU and a growing number of US states could encourage other countries to follow suit.

Levels, distribution, and health risk assessment of phthalic acid esters in urban surface soils of Nagpur city, India

Surface soil samples from residential, commercial, and industrial areas of Nagpur city, India, were collected to study the levels, distribution, and impact of land use patterns on phthalic acid ester (PAEs) contamination. The Σ6PAEs concentrations in soils from residential, commercial, and industrial areas ranged between 6,493 to 13,195 µg/kg, 707 to 18,446 µg/kg, and 1,882 to 5,004 µg/kg with medians of 10,399, 6,199, and 3,401 µg/kg, respectively. Bis-2-ethylhexyl phthalate (DEHP) and dimethyl phthalate (DMP) were the dominant PAEs in the urban soils. The concentrations of DEHP and DMP were significantly greater than those in Ontario's soil quality guidelines. Among the PAEs, benzyl-butyl phthalate (BzBP) was found at relatively high concentrations (1,238 and 9,171 µg/kg) at two locations (i.e., S1 and S15). The chronic toxic risk (CTR) of PAEs was below the threshold, although the risk to children through ingestion and dermal exposure routes was greater than that to adults. The CR due to BzBP and DEHP were below the threshold level; however, the CR due to DMP was > 1 × 10-6 in residential areas. The cumulative CR of the six PAEs for adults (1.33-1.41 × 10-5) and children (8.08-8.89 × 10-6) surpassed the threshold level. This study revealed that PAEs in urban soils pose a risk to public health and require immediate risk reduction strategies.

Evaluation of environmental contamination in beeswax products

Beeswaxes are used as a coating agent or as a wrapping material for food products making them potentially ingested by consumers. There is no regulation yet in Europe giving maximum levels of contaminants in this type of product. Nevertheless, being a natural product, they are exposed to environmental pollution, thus it appears necessary to establish their contamination rate in order to evaluate potential human exposure. In this study, a method of extraction of different environmental contaminants including pesticides, phthalates, PAHs and phenols was developed. Based on a hot Soxhlet extraction, followed by cleaning steps, the method was validated for the quantitation of the cited contaminants by LC-MS/MS and GC-(MS)/MS. Three different types of waxes were analyzed including typical white waxes (Cera Alba) and yellow waxes (Cera Flava). It was shown that all waxes had the presence of at least one contaminant and that phthalates, in particular DEHP, was present in all beeswax samples. Insecticides were found in majority among all the classes of pesticides screened. The yellow waxes were found to be contaminated with the highest rates of PAHs (60%), pesticides (75%) and phenols (40%). The detection frequency of PAHs, in contrast to phthalates, was the lowest for all the types of waxes combined.

A systematic review of global distribution, sources and exposure risk of phthalate esters (PAEs) in indoor dust

Phthalate esters (PAEs) are a class of plasticizers that are readily released from plastic products, posing a potential exposure risk to human body. At present, much attention is paid on PAE concentrations in indoor dust with the understanding of PAEs toxicity. This study collected 8187 data on 10 PAEs concentrations in indoor dusts from 26 countries and comprehensively reviewed the worldwide distribution, influencing factors, and health risks of PAEs. Di-(2-ethylhexyl) phthalate (DEHP) is the predominant PAE with a median concentration of 316 μg·g-1 in indoor dust. Polyvinyl chloride wallpaper and flooring and personal care products are the main sources of PAEs indoor dust. The dust concentrations of DEHP show a downward trend over the past two decades, while high dust concentrations of DiNP are found from 2011 to 2016. The median dust contents of 8 PAEs in public places are higher than those in households. Moreover, the concentrations of 9 PAEs in indoor dusts from high-income countries are higher than those from upper-middle-income countries. DEHP in 69.8% and 77.8% of the dust samples may pose a potential carcinogenic risk for adults and children, respectively. Besides, DEHP in 16.9% of the dust samples may pose a non-carcinogenic risk to children. Nevertheless, a negligible risk was found for other PAEs in indoor dust worldwide. This review contributes to an in-depth understanding of the global distribution, sources and health risks of PAEs in indoor dust.

Global Environmental and Toxicological Data of Emerging Plasticizers: Current Knowledge, Regrettable Substitution Dilemma, Green Solution and Future Perspectives

The global plasticizer market is projected to increase from $17 billion in 2022 to $22.5 billion in 2027. Various emerging/alternative plasticizers entered the market following the ban on several phthalate plasticizers because of their harmful effects. However, there is limited data (especially peer-reviewed) on emerging plasticizers' toxicity and environmental impact. This review compiles available data on toxicity, exposure, environmental effects, and safe production of emerging plasticizers. It identifies gaps in scientific research and provides evidence that emerging plasticizers are potential cases of regrettable substitution. Several alternative plasticizers, such as acetyl tributyl citrate (ATBC), diisononyl cyclohexane-1,2 dicarboxylate (DINCH), tris-2-ethylhexyl phosphate (TEHP), tricresyl phosphate (TCP), tris-2-ethylhexyl phosphate (TPHP), bis-2-ethylhexyl terephthalate (DEHT), and tris-2-ethylhexyl trimellitate (TOTM), show potential as endocrine disrupting properties and other toxic characteristics. Some chemicals like bis-2-ethylhexyl adipate (DEHA), diisobutyl adipate (DIBA), ATBC, DINCH, bis-2-ethylhexyl sebacate (DOS), diethylene glycol dibenzoate (DEGDB), DEHT, and phosphate esters showed the potential to cause toxicity in aquatic species. Plus, there is great lack of information on compounds like diisononyl adipate (DINA), dibutyl adipate (DBA), diisodecyl adipate (DIDA), dipropylene glycol dibenzoate (DPGDB), dibutyl sebacate (DBS), alkylsulfonic phenyl ester (ASE), trimethyl pentanyl diisobutyrate (TXIB), DEGDB and bis-2-ethylhexyl sebacate (DOS). Some compounds like epoxidized soybean oil (ESBO), castor-oil-mono-hydrogenated acetate (COMGHA), and glycerin triacetate (GTA) are potentially safer or less toxic. Alternative plasticizers such as adipates (LogKow 4.3-10.1), cyclohexane dicarboxylic acids (LogKow 10), phosphate esters (LogKow 2.7-9.5), sebacates (LogKow 6.3-10.1), terephthalates (LogKow 8.4), and vegetable oil derivatives (LogKow 6.4-14.8) have logKow values that are comparable to phthalate plasticizers (LogKow 7.5-10.4), indicating potential bioaccumulation and health consequences. Field studies have demonstrated that phosphate esters can undergo bioaccumulation and biomagnification, but there is a lack of bioaccumulation studies for other compounds. We also discuss the metabolism of emerging plasticizers, though data is limited. Our article highlights that numerous alternative compounds display potential health and ecological risks, indicating they might not be suitable substitutes for legacy plasticizers. There is also a lack of scientific data on most emerging plasticizers. This way, we call for increased research and timely regulatory action to prevent global contamination and health risks. Finally, this study presents a scientifically robust protocol to avoid harmful substitutions and ensure the production of safer chemicals.

Comprehensive characterization of organic compounds in indoor dust after generic sample preparation with SUPRAS and analysis by LC-HRMS/MS

In this study supramolecular solvents (SUPRAS) are employed for the first time to perform a wide screening of organic compounds in indoor dust samples. The potential of SUPRAS to efficiently extract a wide polarity range of compounds, and to simplify and improve the green properties of sample treatment in this area are discussed. SUPRAS made up of inverse aggregates of hexanol in tetrahydrofuran:water mixtures, which have been previously and successfully applied to the target determination of a variety of organic contaminants in different environmental matrices, were employed. Analysis was done with liquid chromatography and high resolution mass spectrometry. Twelve samples from public buildings (six educative buildings, two food stores, two nightclubs, one office and a coffee shop) were collected in South Spain. A total of 146 compounds were detected by target (∼33 %), suspect (∼55 %) and non-target screening (∼12 %). Around 86 % of all the compounds were identified (or tentatively identified) with levels of confidence equal or higher than 3. Novel designer drugs of abuse, unreported organophosphorus compounds and well-known organic contaminants, such as bisphenols, parabens, phthalates and flame retardants are reported. Differences with previous studies on wide screening of indoor dust reveal the influence of the employed databases for data processing and of the extraction method together with the different contamination profiles given by the sample location.

A novel method for assessing indoor di 2-ethylhexyl phthalate (DEHP) contamination and exposure based on dust-phase concentration

Phthalates (PAEs) are a group of typical semivolatile organic compounds that are widely present in indoor environments with multiple phases. Indoor air, airborne particle and settled dust are considered to be typical indicators of PAE contamination as well as media of human exposure, and the interactions between them are complex. Among various phthalate compounds, di 2-ethylhexyl phthalate (DEHP) was identified as the predominant individual phthalate in settled dust. The existing DEHP contamination assessment requires multiphase sampling or solving the dynamic mass transfer models with multiple partial differential equations, which are both complicated and time-consuming. This study investigated the influence of the indoor source loading rate, surface type, particle size and cleaning frequency on the partitioning between the settled dust-phase, airborne particle-phase and gas-phase. The concentration correlations of DEHP between multiphases were consequently derived, which balance accuracy and complexity well. By comparison with field sampling data in the literatures, the rationality and accuracy of the concentration correlations were validated. Based on the concentration correlations, a new method of directly using dust-phase concentration to estimate the non-dietary exposure to DEHP was proposed. The results indicated that ingestion of settled dust contributes the most to non-dietary exposure. Special attention should be given to infants and toddlers, who suffer the highest daily exposure to DEHP among all age groups. This study provides a new and efficient solution for estimating indoor DEHP pollution loads conveniently and rapidly, offering valuable insights for future research in this field.

Comprehensive assessment of phthalates in indoor dust across China between 2007 and 2019: Benefits from regulatory restrictions

China is the largest producer and consumer of phthalates in the world. However, it remains unclear whether China's phthalate restrictions have alleviated indoor phthalate pollution. We extracted the concentrations of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), benzyl butyl phthalate (BBP), and bis(2-ethylhexyl) phthalate (DEHP) in indoor dust at 2762 sites throughout China between 2007 and 2019 from the published literature. Based on these data, we investigated the effects of phthalate restrictions and environmental factors on the temporal-spatial distribution and sources of phthalates and estimated human exposure and risk of phthalates. The results revealed that the mean concentrations of phthalates in indoor dust throughout China decreased in the following order: DEHP > DBP > DIBP > DMP > DEP > BBP. The concentrations of six phthalates were generally higher in northern and central-western China than in southern regions. BBP and DEHP concentrations decreased by 73.5% and 17.9%, respectively, from 2007 to 2019. Sunshine was a critical environmental factor in reducing phthalate levels in indoor dust. Polyvinyl chloride materials, personal care products, building materials, and furniture were the primary sources of phthalates in indoor dust. The phthalates in indoor dust posed the most significant threat to children and older adults. This study provides a picture of phthalate pollution, thus supporting timely and effective policies and legislation.

Organic toxicants and emerging contaminants in hospital interiors before and during the SARS-CoV2 pandemic: alkanes and PAHs

Indoor pollution and deposition dust (DD), in particular, are acquiring concern, due to long exposure time and importance of intake by humans through contact and ingestion. Hospitals look a special category of sites, owing to peculiar contaminants affecting them and to presence of people prone to adverse effects induced by toxicants. Four in-field campaigns aimed at understanding the chemical composition of DD were performed in five Italian hospitals. Measurements were performed before (autumn 2019), during (spring 2021), and after (winter 2022) the peak of SARS-CoV2 and when restrictions caused by pandemic were revoked (winter 2023). Parallel measurements were made outdoors (2022), as well as in a university and a dwelling. Targeted contaminants were n-alkanes and polycyclic aromatic hydrocarbons (PAHs), while iso- and anteiso-alkanes were analyzed to assess the impact of tobacco smoking. Total n-alkanes ranged from 3.9 ± 2.3 to 20.5 ± 4.2 mg/g, with higher percentages of short chain homologs in 2019. PAHs ranged from 0.24 ± 0.22 to 0.83 ± 0.50 mg/g, with light congeners (≤ 228 a.m.u.) always exceeding the heavy ones (≥ 252 a.m.u.). According to carbon preference indexes, alkanes originated overall from anthropogenic sources. Microorganisms resulted to affect a hospital, and tobacco smoke accounted for ~ 4-20‰ of DD mass. As for PAH sources, the diagnostic concentration ratios suggested the concourse of biological matter burning and vehicle emission. Benzo[a]pyrene equivalent carcinogenic and mutagenic potencies of depositions at hospitals ranged ~ 9-39 μg/g and ~ 15-76 μg/g, respectively, which seems of concern for health. DD composition in hospitals was different from that outside the premises, as well as that found at university and at dwelling.

Legacy and Emerging Plasticizers and Stabilizers in PVC Floorings and Implications for Recycling

Hazardous chemicals in building and construction plastics can lead to health risks due to indoor exposure and may contaminate recycled materials. We systematically sampled new polyvinyl chloride floorings on the Swiss market (n = 151). We performed elemental analysis by X-ray fluorescence, targeted and suspect gas chromatography-mass spectrometry analysis of ortho-phthalates and alternative plasticizers, and bioassay tests for cytotoxicity and oxidative stress, and endocrine, mutagenic, and genotoxic activities (for selected samples). Surprisingly, 16% of the samples contained regulated chemicals above 0.1 wt %, mainly lead and bis(2-ethylhexyl) phthalate (DEHP). Their presence is likely related to the use of recycled PVC in new flooring, highlighting that uncontrolled recycling can delay the phase-out of hazardous chemicals. Besides DEHP, 29% of the samples contained other ortho-phthalates (mainly diisononyl and diisodecyl phthalates, DiNP and DiDP) above 0.1 wt %, and 17% of the samples indicated a potential to cause biological effects. Considering some overlap between these groups, they together make up an additional 35% of the samples of potential concern. Moreover, both suspect screening and bioassay results indicate the presence of additional potentially hazardous substances. Overall, our study highlights the urgent need to accelerate the phase-out of hazardous substances, increase the transparency of chemical compositions in plastics to protect human and ecosystem health, and enable the transition to a safe and sustainable circular economy.

HBM4EU e-waste study: Occupational exposure of electronic waste workers to phthalates and DINCH in Europe

Workers involved in the processing of electronic waste (e-waste) are potentially exposed to toxic chemicals, including phthalates and alternative plasticizers (APs). Dismantling and shredding of e-waste may lead to the production of dust that contains these plasticizers. The aim of this study, which was part of the European Human Biomonitoring Initiative (HBM4EU), was to assess the exposure to phthalates (e.g. di-(2-ethylhexyl) phthalate (DEHP), diethyl phthalate (DEP), di-butyl phthalate (DBP), butyl-benzyl phthalate (BBzP), di-isononyl phthalate (DiNP), di-isodecyl phthalate (DiDP) and cyclohexane-1,2-dicarboxylic di-isononyl ester (DINCH) in e-waste workers from ten European companies. This was achieved by (i) analysing urine samples from 106 e-waste workers collected at the beginning and at the end of the work week, (ii) comparing these with urine samples from 63 non-occupationally exposed controls, and (iii) analysing settled floor dust collected in e-waste premises. Significantly higher urinary concentrations of seven out of thirteen phthalates and DINCH metabolites were found in the e-waste workers compared to the control population. However, no significant differences were found between pre- and post-shift concentrations in the e-waste workers. Concentrations of DBP, DEHP and DiDP in dust were weakly to moderately positively correlated with their corresponding urinary metabolite concentrations in the e-waste workers (Spearman's ρ = 0.4, 0.3 and 0.2, respectively). Additionally, significantly lower urinary concentrations of nine phthalates and DINCH metabolites were found in e-waste workers using respiratory protective equipment (RPE) during their work activities, reflecting the potential benefits of RPE to prevent occupational exposure to phthalates and DINCH. The estimated daily intake (EDI) values obtained in this study were lower than the corresponding tolerable daily intake (TDI) adopted by the European Food Safety Authority (EFSA) for the general population, suggesting that the risk for negative health consequences in this population of e-waste workers from exposure to phthalates and DINCH is expected to be low. This was confirmed by the urinary metabolite concentrations of all workers being lower than the HBM4EU guidance values derived for the occupational exposed and general population. This study is one of the first to address the occupational exposure to phthalates and DINCH in Europe in e-waste dismantling workers, combining a human biomonitoring approach with analysis of settled indoor dust.

Reducing Transdermal Uptake of Semivolatile Plasticizers from Indoor Environments: A Clothing Intervention

Models and laboratory studies suggest that everyday clothing influences the transdermal uptake of semivolatile organic compounds, including phthalate plasticizers, from indoor environments. However, this effect has not been documented in environmental exposure settings. In this pilot study, we quantified daily excretion of 17 urinary metabolites (μg/day) for phthalates and phthalate alternatives in nine participants during 5 days. On Day 0, baseline daily excretion was determined in participants' urine. Starting on Day 1, participants refrained from eating phthalate-heavy foods and using personal care products. On Days 3 and 4, participants wore precleaned clothing as an exposure intervention. We observed a reduction in the daily excretion of phthalates during the intervention; mono-n-butyl phthalate, monoisobutyl phthalate (MiBP), and monobenzyl phthalate were significantly reduced by 35, 38, and 56%, respectively. Summed metabolites of di(2-ethylhexyl)phthalate (DEHP) were also reduced (27%; not statistically significant). A similar reduction among phthalate alternatives was not observed. The daily excretion of MiBP during the nonintervention period strongly correlated with indoor air concentrations of diisobutyl phthalate (DiBP), suggesting that inhalation and transdermal uptake of DiBP from the air in homes are dominant exposure pathways. The results indicate that precleaned clothing can significantly reduce environmental exposure to phthalates and phthalate alternatives.

Co-occurrence of phthalate and non-phthalate plasticizers in dust and hand wipes: A comparison of levels across various sources

E-waste dismantlers' occupational exposure to plasticizers, particularly non-phthalate (NPAE) plasticizers, is poorly understood. This study monitored 11 phthalates (PAEs) and 16 NPAEs in dust and hand wipe samples from Central China e-waste workplace and ordinary homes. Concentrations of plasticizers in dust from e-waste dismantling workshops (median: 217 μg/g) were significantly lower than that from ordinary homes (462 μg/g; p < 0.01), however, the trend was similar but not significant in hand wipes from these two scenarios (50.2 vs. 72.3 μg/m2; p = 0.139). PAEs were still the dominant plasticizers, which is, on average, 5.46 and 3.58-fold higher than NPAEs. In all samples, di-(2ethylhexyl) phthalate (65.4%) and tri-octyl trimellitate (44.9%) were the most common PAE and NPAE plasticizers. Increasing dust concentrations of di-iso-nonyl ester 1,2-cyclohexane dicarboxylic acid, citrates and sebacates were significantly associated with their levels in worker's hand wipe, by contrast, this trend was not found in general population. Dust ingestion was the main channel, followed by hand-to-mouth contact, all participants' daily plasticizer intakes (median: 154 ng/kg bw/day) are within safety limits. Our work highlights knowledge gaps about co-exposure to PAEs and NPAEs by multiple pathways in occupational e-waste workers, which could provide baseline data in the future.

Phthalates in plastic stationery in China and their exposure risks to school-aged children

Phthalates have been strictly banned in children's products in many countries. However, as a product with a high frequency of daily contact with children, stationery is not strictly regulated for phthalates in many countries and the occurrences and risks of phthalates in stationery are rarely reported. In this study, the contents of sixteen types of common phthalates in stationery were determined and the exposure risk of these phthalates to children was also estimated. The total contents of phthalates in all stationery ranged from 5.56 to 3.46 × 105 μg/g, with a median value of 1.48 × 104 μg/g. Polyvinyl chloride (PVC) desk mats (DMs) contained the highest contents of phthalates among all types of stationery. Percutaneous absorption and hand-to-mouth ingestion levels of phthalates for school-age children from the DMs were 2.03 × 10-5 - 10.14 μg/kg-Bw/day and 2.14 × 10-5 - 10.67 μg/kg-Bw/day, respectively. Di-2-ethylhexyl phthalate (DEHP) had the highest proportion, detection rate, and exposure level among all measured phthalates. Our study revealed that phthalates in PVC stationery, especially classroom DMs, at both contents and exposure risks, were higher than those in many other children's plastic products. It was necessary to strengthen the management of plastic stationery from the perspective of materials and phthalates addition.

Analysis and contamination levels of ten phthalic acid esters (PAEs) in Chinese commercial bubble tea: a comparison with commercial milk

Phthalic acid ester (PAE) contamination in popular drink bubble tea has been hardly studied in the world. In this work, a liquid-liquid extraction following solid phase extraction (LLE-SPE)-UPLC-MS/MS method was first established for trace determination of ten PAEs in bubble tea. The developed method was validated with respect to linearity (R2 > 0.992), low limit of detections (LODs, 0.49-3.16 µg/L), and satisfactory recoveries (61.8-127.6%) with a low relative standard derivations (RSDs, 1.1-16.4%), which was also validated for commercial milk. Six out of ten PAEs, i.e., diethylhexyl phthalate (DEHP), dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), diethyl phthalate (DEP), dihexyl phthalate (DHP), and diphenyl phthalate (DPP) were detected in Chinese bubble tea with concentrations ranging from not detection (ND) to 53.43 µg/L, while DEHP, DBP, DIBP, DEP, and dimethyl phthalate (DMP) were detected in commercial milk with concentrations ranging from ND to 110.58 µg/L. The respective average concentrations of DEHP in Chinese bubble tea and commercial milk were 19.40 and 23.46 µg/L, which were over two times that in drinking water quality standards of several countries including Israel, Korea, Oman, and Singapore (i.e., 8 µg/L). Calculated with human estimated daily intake (EDI), the average EDIs of five out of seven PAEs in bubble tea were higher than those in commercial milk. For example, the calculated EDI of DIBP in bubble tea was 5 times that in commercial milk, while their respective corresponding EDIs of DBP and DEHP were over 2.4 and 1.6 times. Based on estrogen equivalence (EEQ) with the unit of ng E2/L, the average EEQs of the ten PAEs in Chinese bubble tea and commercial milk were 14.26 and 17.06 ng E2/L, which were 52.8 and 62.3 times the observed effect concentration that could cause egg mortality of zebrafish. It is evident that the potential estrogenic effect of PAEs in bubble tea and commercial milk cannot be negligible. Given the fact that PAE contamination in bubble tea has been hardly investigated, such study is urgently to be performed in a global view.

Derivation and application of indoor air screening values for inhalation exposure to semi-volatile organic compounds

Semi-volatile organic compounds (SVOCs) are being increasingly studied in indoor air. The absence of health-based inhalation exposure guidelines for most SVOCs impedes the interpretation of indoor air concentrations from a health risk context. To accelerate the derivation of screening values for a large number of SVOCs, a tiered framework was developed to evaluate and adjust published hazard assessments for SVOCs to calculate benchmarks relevant for evaluation of inhalation risk. Inhalation screening values were derived for 43 SVOCs considered in this study, most of which required extrapolation from oral exposure guidelines. The screening values were compared to published SVOC concentrations in homes in Canada to evaluate the potential health risks of chronic exposure to SVOCs in indoor residential environments. SVOCs that could be prioritized for further evaluation were dibutyl phthalates (DBP), di(2-ethylhexyl) phthalate (DEHP) and polybrominated diphenyl ethers (PBDEs). The framework could be applied more broadly in the future to derive screening values for other non-traditional indoor air contaminants with limited inhalation hazard data or assessments.

Endocrine disrupting compounds in the baby's world - A harmful environment to the health of babies

Globally, there has been a significant increase in awareness of the adverse effects of chemicals with known or suspected endocrine-acting properties on human health. Human exposure to endocrine disrupting compounds (EDCs) mainly occurs by ingestion and to some extent by inhalation and dermal uptake. Although it is difficult to assess the full impact of human exposure to EDCs, it is well known that timing of exposure is of importance and therefore infants are more vulnerable to EDCs and are at greater risk compared to adults. In this regard, infant safety and assessment of associations between prenatal exposure to EDCs and growth during infancy and childhood has been received considerable attention in the last years. Hence, the purpose of this review is to provide a current update on the evidence from biomonitoring studies on the exposure of infants to EDCs and a comprehensive view of the uptake, the mechanisms of action and biotransformation in baby/human body. Analytical methods used and concentration levels of EDCs in different biological matrices (e.g., placenta, cord plasma, amniotic fluid, breast milk, urine, and blood of pregnant women) are also discussed. Finally, key issues and recommendations were provided to avoid hazardous exposure to these chemicals, taking into account family and lifestyle factors related to this exposure.

Physico-chemical characterization of indoor settled dust in Children's microenvironments in Ikeja and Ota, Nigeria

Indoor dust is a collection of particles identified as a major reservoir for several emerging indoor chemical pollutants. This study presents indoor dust particles' morphology and elemental composition in eight children's urban and semi-urban microenvironments (A-H) in Nigeria. Samples were collected using a Tesco vacuum cleaner and analyzed with scanning electron microscopy coupled with an energy-dispersive X-ray (SEM-EDX). The morphology results confirm the presence of alumino silicates, mineral particles and flakes, fly ash and soot, and soot aggregates deposited on alumino silicate particles in the sampled microenvironments. These particles may trigger serious health concerns that directly or indirectly affect the overall well-being of children. From the EDX analysis, the trend of elements (w/w %) in the dust particles across the sampled sites was silicon (386) > oxygen (174)> aluminium (114) > carbon (34.5) > iron (28.0) > calcium (16.7) > magnesium (14.2) > sodium (7.92) > potassium (7.58) > phosphorus (2.22) > lead (2.04) > manganese (1.17) > titanium (0.21). Lead (Pb), a toxic and carcinogenic heavy metal, was observed in locations A and B. This is a concern without a safe lead level because of the neurotoxicity effect on children. As a result, further research on the concentrations, bioavailability, and health risk assessment of heavy metals in these sampled locations is recommended. Furthermore, frequent vacuum cleaning, wet moping and adequate ventilation systems will significantly reduce the accumulation of indoor dust-bound metals.

Endocrine disrupting chemicals in indoor dust: A review of temporal and spatial trends, and human exposure

Several chemicals with widespread consumer uses have been identified as endocrine-disrupting chemicals (EDCs), with a potential risk to humans. The occurrence in indoor dust and resulting human exposure have been reviewed for six groups of known and suspected EDCs, including phthalates and non-phthalate plasticizers, flame retardants, bisphenols, per- and polyfluoroalkyl substances (PFAS), biocides and personal care product additives (PCPs). Some banned or restricted EDCs, such as polybrominated diphenyl ethers (PBDEs), di-(2-ethylhexyl) phthalate (DEHP), bisphenol A (BPA), perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), are still widely detected in indoor dust in most countries, even as the predominating compounds of their group, but generally with decreasing trends. Meanwhile, alternatives that are also potential EDCs, such as bisphenol S (BPS), bisphenol F (BPF), decabromodiphenyl ethane (DBDPE) and organophosphate flame retardants (OPFRs), and PFAS precursors, such as fluorotelomer alcohols, have been detected in indoor dust with increasing frequencies and concentrations. Associations between some known and suspected EDCs, such as phthalate and non-phthalate plasticizers, FRs and BPs, in indoor dust and paired human samples indicate indoor dust as an important human exposure pathway. Although the estimated daily intake (EDI) of most of the investigated compounds was mostly below reference values, the co-exposure to a multitude of known or suspected EDCs requires a better understanding of mixture effects.

Fire accelerant classification from GC–MS data of suspected arson cases using machine–learning models

Using a practical GC-MS dataset containing approximately 4000 suspected arson cases, three machine-learning based classification models were developed and their performances were evaluated. All models trained for classifying the data from fire residue into six categories; no fire accelerants detected or else one of fire accelerants was used within gasoline, kerosene, diesel, solvents, or candle. The classification accuracies of the random forest, supporting vector machine, and convolutional neural network model were 0.88, 0.88, and 0.92, respectively. By calculating feature importance of the random forest model, several potential chemical fingerprints of fire accelerants were discovered.

Health Risks Posed by Dermal and Inhalation Exposure to High Concentrations of Chlorinated Paraffins Found in Soft Poly(vinyl chloride) Curtains

Chlorinated paraffins (CPs) are used in many products, including soft poly(vinyl chloride) curtains, which are used in many indoor environments. Health hazards posed by CPs in curtains are poorly understood. Here, chamber tests and an indoor fugacity model were used to predict CP emissions from soft poly(vinyl chloride) curtains, and dermal uptake through direct contact was assessed using surface wipes. Short-chain and medium-chain CPs accounted for 30% by weight of the curtains. Evaporation drives CP migration, like for other semivolatile organic plasticizers, at room temperature. The CP emission rate to air was 7.09 ng/(cm² h), and the estimated short-chain and medium-chain CP concentrations were 583 and 95.3 ng/m³ in indoor air 21.2 and 172 μg/g in dust, respectively. Curtains could be important indoor sources of CPs to dust and air. The calculated total daily CP intakes from air and dust were 165 ng/(kg day) for an adult and 514 ng/(kg day) for a toddler, and an assessment of dermal intake through direct contact indicated that touching just once could increase intake by 274 μg. The results indicated that curtains, which are common in houses, could pose considerable health risks through inhalation of and dermal contact with CPs.

Seasonal variations of airborne phthalates and novel non-phthalate plasticizers in a test residence in cold regions: Effects of temperature, humidity, total suspended particulate matter, and sources

As a class of plasticizers widely used in consumer products, some phthalate esters (PAEs) have been restricted due to their adverse health effects and ubiquitous presence, leading to the introduction of alternative non-phthalates plasticizers (NPPs) to the market. However, few studies focus on the influence of environmental parameters on the presence of these plasticizers and the potential human health risks for people living in poorly ventilated indoor spaces in cold regions. We investigated the trends of PAEs and NPPs in air in a typical indoor residence in northern China for over one year. The air concentrations of PAEs were significantly higher than those of NPPs (p < 0.05), indicating that PAEs are still the dominant plasticizers currently being used in the studied residence. PAEs showed seasonal fluctuation patterns of the highest levels found in summer and autumn. The temperature and relative humidity dependence for most PAEs and NPPs decreased with decreasing vapor pressure. Concentrations of the high molecular weight NPPs and PAEs positively correlated with total suspended particles (TSP). It is worth noting that the peak concentrations of PAEs and NPPs were found when the haze occurred in autumn. Principal component analysis (PCA) suggested the diverse applications of PAEs and NPPs in the indoor environment. The hazard index (HI) values observed in this study were all below international guidelines (<1); however, the average carcinogenic risk (CR) values for some compounds exceeded acceptable levels (One in a million), which raised concerns about the possibility of carcinogenicity for people living indoors for long periods of time in cold regions.

Remediation of phthalate acid esters from contaminated environment—Insights on the bioremedial approaches and future perspectives

Phthalates are well-known emerging pollutants that are toxic to the environment and human health. Phthalates are lipophilic chemicals used as plasticizers in many of the items for improving their material properties. These compounds are not chemically bound and are released to the surroundings directly. Phthalate acid esters (PAEs) are endocrine disruptors and can interfere with hormones, which can cause issues with development and reproduction, thus there is a huge concern over their existence in various ecological surroundings. The purpose of this review is to explore the occurrence, fate, and concentration of phthalates in various environmental matrices. This article also covers the phthalate degradation process, mechanism, and outcomes. Besides the conventional treatment technology, the paper also aims at the recent advancements in various physical, chemical, and biological approaches developed for phthalate degradation. In this paper, a special focus has been given on the diverse microbial entities and their bioremedial mechanisms executes the PAEs removal. Critically, the analyses method for determining intermediate products generated during phthalate biotransformation have been discussed. Concluisvely, the challenges, limitations, knowledge gaps and future opportunities of bioremediation and their significant role in ecology have also been highlighted.

Tetrabromobisphenol A and hexabromocyclododecanes from interior and surface dust of personal computers: implications for sources and human exposure

Tetrabromobisphenol A (TBBPA) and hexabromocyclododecane isomers (HBCDs) are widely detected in indoor environments, but the research on the accumulation, contamination, and human exposure of TBBPA and HBCDs in electronic products dust is still limited. It is unclear whether electronic products might pose human health risk via dust ingestion and dermal absorption. In this study, the levels and distributions of TBBPA and HBCDs were investigated in the personal computer (PC) interior dust and PC surface (upper and bottom) wipes. The median concentrations of TBBPA in PC interior dust, upper, and bottom surface wipes were 168.1 ng/g, 13.2 ng/m², and 15.2 ng/m², respectively. These levels were generally higher than those of HBCDs, which were 95.2 ng/g, 11.7 ng/m², and 12.3 ng/m², respectively. No significant correlations were found among the PC upper and bottom surface wipes, and interior dust, indicating different sources of TBBPA and HBCDs in PC interior and surface dust. The TBBPA and HBCDs in the PC interior dust were mainly released from inner PC materials, while the sources of target compounds on the surface wipes were likely from external environments. The exposure values of two occupational populations (including PC owners and PC repair workers) to TBBPA and HBCDs were measured by PC interior dust and upper surface wipes. The results imply dust ingestion (including hand-to-mouth uptake) is the main contributor of the exposure route to TBBPA and HBCDs for both PC owners and repair workers. Compared to PC owners, PC repair workers showed the greater risk in exposure assessment, which should be paid more attention.

Phthalate exposure is associated with more rapid body fat gain in midlife women: The Study of Women's Health Across the Nation (SWAN) Multi-Pollutant Study

Obesity is a major threat to health, but the etiology of obesity is incompletely understood. Phthalates, synthetic chemicals ubiquitous in the environment, are suspected to have obesogenic effects, but the relationship of phthalates and obesity in humans remains uncertain. We examined whether phthalate exposure was associated with body fat gain in midlife women. We analyzed data from 1369 women in the Study of Women's Health Across the Nation Multi-Pollutant Study. Eleven phthalate metabolites measured in spot urine samples at baseline (1999/2000) were standardized with covariate-adjusted creatinine. Body weight (BW), fat mass (FM) from dual-energy X-ray absorptiometry (DXA), and body fat percentage (BF%) from DXA were measured near-annually until 2016/2017. For each metabolite, linear mixed effects models with time and log2(metabolite) interactions were examined, adjusting for demographic, lifestyle, and menopause-related factors. Analyses were conducted overall and stratified by baseline obesity status. As sensitivity analyses, all analyses were repeated using a second set of metabolites measured in 2002/2003. Higher levels of all metabolites except mono-carboxy-isononyl phthalate were associated with faster increases in BF%. Per doubling of metabolite concentrations, differences in five-year BF% change ranged from 0.03 percentage point (ppt) (95% confidence interval (CI): -0.03, 0.09) for mono-isobutyl phthalate to 0.09 ppt (95% CI: 0.02, 0.16) for mono(3-carboxypropyl) phthalate. Results were similar for FM change, but associations with BW change were mostly null. In stratified analyses by baseline obesity status, positive associations were strongest in women who were normal/underweight at baseline. When metabolites from 2002/2003 were used as exposures, most associations were attenuated and not statistically significant, but they remained positive for normal/underweight women. In conclusion, phthalate metabolites were associated with more rapid body fat gain in midlife women, but our results need confirmation given attenuation of estimates in the sensitivity analyses.

Identification of Glucocorticoid Receptor Antagonistic Activities and Responsible Compounds in House Dust: Bioaccessibility Should Not Be Ignored

More and more contaminants in dust have been found to be glucocorticoid receptor (GR) disrupting chemicals. However, little is known about the related potency and responsible toxicants, especially for the main bioaccessible ones in dust. An effect-directed analysis (EDA)-based workflow was developed, including solvent-based exhaustive extraction/tenax-assisted bioaccessible extraction (TBE), high-throughput bioassays, suspect and non-target analysis, as well as in silico candidate selection, for a more realistic identification of responsible contaminants in dust. None of the 39 dust samples from 23 cities in China exhibited GR agonistic activity, while GR antagonistic potencies were detected in 34.8% of samples, being significantly different from the high detection frequency of GR agonistic activities in other environmental media. The GR antagonistic potencies of the dust samples were all reduced after bioaccessible extraction. The mean bioaccessibility of GR antagonistic potency compared with the related exhaustive extracts was 36.8%, and the lowest value was 9%. By using in silico candidate selection, greater than 99% candidate chemical structures which were found by a non-target screening strategy were removed. Di-n-butyl phthalate (DnBP), diisobutyl phthalate (DiBP), and nicotine (NIC) were responsible for the activities of the exhaustive extracts of dust, contributing up to 91% potencies. DiBP and DnBP were also responsible for the bioaccessible activities, contributing up to 79% potencies. However, the contribution from NIC decreased significantly and can be ignored because of its low bioaccessibility. This study suggests that the improved workflow combining extraction, reporter gene bioassays, suspect and non-target analysis, as well as in silico candidate selection is useful for EDA analysis in dust samples. In addition, exhaustive extraction may overestimate the risk of contaminants, while bioaccessibility evaluation based on bioaccessible extraction is essential in both effect evaluation and toxicant identification.

Equilibrium distribution of diethyl phthalate plasticiser in cellulose acetate-based materials: Modelling and parameter estimation of temperature and composition effects

Understanding the transport and fate of semi-volatile organic compounds (SVOCs) such as phthalates in indoor environments is fundamental for quantifying levels of human exposure and preventing adverse health effects. In this context, the partition coefficient of phthalates between indoor built materials and/or consumer goods and the surrounding atmosphere represents a key parameter for determining concentration distributions. Partition coefficients are also of fundamental importance for describing degradation phenomena associated with plasticiser loss from polymeric materials. However, this key parameter has only been determined for a limited number of systems and environmental conditions. Here, we assess the partitioning behaviour of the diethyl phthalate (DEP) plasticiser in cellulose acetate (CA)-based materials for the first time, determining the effects of temperature and plasticiser composition on equilibrium distributions at temperatures between 20 and 80 °C and using CA samples with DEP contents ranging from 6 to 22 wt%. Additionally, we propose a model to describe and quantify the effect of temperature and plasticiser composition, with model parameters being estimated using non-linear regression and measurements from 130 distinct experiments. Finally, we assess the suitability of our developed model to simulate the migration of DEP from CA-based materials.

The p-Phthalates Terephthalic Acid and Dimethyl Terephthalate Used in the Manufacture of PET Induce In Vitro Adipocytes Dysfunction by Altering Adipogenesis and Thermogenesis Mechanisms

Public health concerns associated with the potential leaching of substances from Polyethylene terephthalate (PET) packaging have been raised due to the role of phthalates as endocrine-disrupting chemicals or obesogens. In particular, changes in the environment such as pH, temperature, and irradiation can improve contaminant migration from PET food packaging. In this study, the in vitro effects of p-phthalates terephthalic acid (TPA) and dimethyl terephthalate (DMT) on murine adipocytes (3T3-L1) were evaluated using concentrations that might be obtained in adult humans exposed to contaminated sources. TPA and, in particular, DMT exposure during 3T3-L1 differentiation increased the cellular lipid content and induced adipogenic markers PPAR-γ, C/EBPß, FABP4, and FASN, starting from low nanomolar concentrations. Interestingly, the adipogenic action of TPA- and DMT-induced PPAR-γ was reverted by ICI 182,780, a specific antagonist of the estrogen receptor. Furthermore, TPA and DMT affected adipocytes’ thermogenic program, reducing pAMPK and PGC-1α levels, and induced the NF-κB proinflammatory pathway. Given the observed effects of biologically relevant chronic concentrations of these p-phthalates and taking into account humans’ close and constant contact with plastics, it seems appropriate that ascertaining safe levels of TPA and DMT exposure is considered a high priority.

Accumulation and translocation of traditional and novel organophosphate esters and phthalic acid esters in plants during the whole life cycle

Organophosphate esters (OPEs) and phthalic acid esters (PAEs) are widespread contaminants in the environment. The variations of these chemicals in plants throughout their life cycle is little known. In this study, OPEs, OPE metabolites, and PAEs in peanut and corn grown under field conditions, soil, and air were measured to understand the uptake and translocation, distributions in the plant compartments, and metabolism in the plants. The soil concentrations showed an enrichment effect of OPEs onto the rhizosphere soil but a depletion effect of PAEs on rhizosphere soils. The PAE concentrations between peanut (with a mean of 1295 ng/g dw) and corn (3339 ng/g dw) were significantly different, but the OPE concentrations were not significantly different (with means of 15.6 and 19.2 ng/g dw, respectively). OPE metabolites were also detected in the plants, with lower concentrations and detection rates. Similarities and differences in the temporal variations of the concentrations of traditional OPEs, novel OPEs, and PAEs in plants during their growth were observed. The variations were dependent on both plant species and particular tissues. The leaf compartment is the most important reservoir of OPEs and PAEs (but not OPE metabolites) for both species, highlighting the importance of an aerial uptake pathway. The chemicals have a low potential to be translocated into peanut and corn kernels, reducing their risks via food consumption. Less hydrophobic compounds have higher root concentration factors in this study. These observations differ from those of previous hydroponic experiments.

Occurrence, distribution and sources of phthalates and petroleum hydrocarbons in tropical estuarine sediments (Mandovi and Ashtamudi) of western Peninsular India

The present study provides baseline information on the concentration levels, distribution characteristics and pollution sources of environmental contaminants, such as phthalic acid esters (PAEs or phthalates) and petroleum hydrocarbons in surface sediments of the tropical estuaries (Mandovi and Ashtamudi) from western Peninsular India. Total PAEs (∑₅PAEs), hopanes, steranes and diasteranes concentrations from Ashtamudi estuary ranged from 7.77 to 1478.2 ng/g, n.d.-363.2 ng/g, n.d.-121.5 ng/g and n.d.-116.6 ng/g, respectively. Likewise, PAEs (∑₆PAEs), steranes and diasteranes concentrations from Mandovi estuary ranged from 60.1 to 271.9 ng/g, 2.33-40.1 ng/g and 2.28-23.0 ng/g, respectively. The PAEs comprising di-isobutyl phthalate (DIBP), dibutyl phthalate (DBP), an isomer peak for DBP, di(2-ethylhexyl) phthalate (DEHP), di-isononyl phthalate were dominant in Ashtamudi estuary sediments, while PAEs including diethyl phthalate, DIBP, DBP and its isomer, DEHP, di(2-ethylhexyl) terephthalate were detected in the Mandovi sediment samples. The results of this study show an insignificant correlation of TOC with PAEs, and indicates that the varying spatial distributions of the PAEs in both the estuaries can be the result of discharge sources. The higher concentration of PAE congeners was noticed in Ashtamudi, a Ramsar wetland site, that can be attributed to land-based plastic waste. The petroleum biomarkers were abundantly present in Mandovi estuary due to anthropogenic activities such as boating and spillage from oil tankers. The findings of the present study will serve as a reference point for future investigation of organic contaminants in Indian estuaries, and calls for attention towards implementing effective measures in controlling the pervasion of the PAEs and petroleum biomarkers.

Urinary metabolites and handwipe phthalate levels among adults and children in southern China: Implication for dermal exposure

Paired handwipe and urine samples were collected from adult (n = 130) and child (n = 82) residents of a typical urban community in southern China to examine relationships between external and internal exposure as well as the contribution of dermal absorption to the exposure of phthalates. The concentrations and composition profiles of phthalates were similar in handwipes from both adults and children, and contained mainly di-2-ethylhexyl phthalate (DEHP), di-n-butyl phthalate (DnBP) and di-iso-butyl phthalate (DiBP), consistent with profiles of phthalates in air and dust. The major metabolites of these phthalates, i.e., mono-n-butyl phthalate (mnBP) from DnBP, mono-iso-butyl phthalate (miBP) from DiBP and three metabolites of DEHP (namely mEHP, mEHHP and mEOHP) were widely detected in paired urine samples. Positive correlations were found between contamination levels of DiBP and DnBP in handwipes and their corresponding urinary metabolites, whereas no significant correlation was observed for DEHP. This suggests that dermal absorption might be an important exposure pathway particularly for low molecular weight phthalates. Our study shows that dermal absorption is a non-negligible exposure pathway for phthalates, to which children are particularly sensitive since the contribution of dermal uptake to the internal exposure of phthalates was higher in children than adults.

Transfer of Frictional Contact Derived Phthalates from Pad Surface Enhances Dermal Exposure

Dermal exposure to chemicals derived from object surface contact is an important contributor to increased health risk. However, chemical transfer induced by mechanical friction between dermal and object surface has yet to be adequately addressed. To fill this knowledge gap, rubbing fabrics were used as surrogate skins to stimulate dermal mechanical friction with pad products with phthalates as target analytes. The results showed that the amounts of phthalates transferred increased linearly with contact burden (50-1000 g), contact duration (1-10 min), and sliding speed (3.0-9.0 cm s^-1). The surface texture of surrogate skins dictated the accumulation of phthalates. Net/pocket micro-surface structures of rubbing fabrics induced a higher accumulation of phthalates than U-shape structures of fabrics with a similar surface roughness. Covering of the pad surface by a layer of textile was effective in minimizing the transfer of phthalates induced by mechanical motion. The estimated transfer efficiency of bis(2-ethylhexyl) ester (DEHP) derived from rubbing friction (0.005-0.05%) upon the pad surface over 8 h was greater than those for gas-phase emission (0.00002-0.0005% over 24 h) and sweat transfer (0.008-0.012% over 24 h). These results indicated that dermal frictional contact with the surface of pad products was an important exposure pathway.

National-scale urinary phthalate metabolites in the general urban residents involving 26 provincial capital cities in China and the influencing factors as well as non-carcinogenic risks

Phthalates (PAEs) are widely used in daily products but can cause a variety of adverse effects in humans. Few studies have been carried out on human internal exposure levels of PAEs on a large-scale, especially in developing countries. In the present study, 1161 urine samples collected from residents of 26 provincial capitals in China were analyzed for nine phthalate metabolites (mPAEs). The chemicals were widely detected, and the median specific gravity adjusted urinary concentration of Σ₉mPAEs was 278 μg/L. Di-(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DnBP) were the main parent PAEs that the residents were exposed to. Demographic characteristics, such as age and educational level, were significantly associated with PAE exposure. Children and the elderly had higher mPAE levels. Subjects with lower educational levels were more frequently exposed to DnBP and DEHP. However, mono-ethyl phthalate showed the opposite trend, i.e., higher concentrations in subjects aged 18-59 years and with higher educational levels. Geographic differences were detected at the national scale. Residents in northeastern and western China had higher levels of mPAEs than those in central China, most likely because of different industrial usage of the chemicals and different living habits and living conditions of the residents. Health risk assessment showed that hazard indices of PAEs ranged from 0.07 to 9.34, with 20.0% of the subjects being concern for potential non-carcinogenic risk as assessed by Monte Carlo simulation. DEHP and DnBP were the primary contributors, representing 96.7% of total risk. This first large-scale study on PAE human internal exposure in China provides useful information on residents' health in a developing country, which could be used for chemical management and health protection.

Occurrence and health risk assessment of phthalate esters in tobacco and soils in tobacco-producing areas of Guizhou province, southwest China

Flue-cured tobacco is one of the important sources of national economy in China. However, Phthalic acid esters (PAEs) are ubiquitous contaminants in the cultivation and growth management of flue-cured tobacco, and attracting more and more attention. Here, six priority PAEs were detected in tobacco and soils and their residue characteristics, pollution sources were analyzed, and their exposure risks to the health of farmers were assessed. The concentration of six total PAEs ranged from 0.78 to 4.79 mg/kg in tobacco with the average of 1.75 mg/kg, and 0.84-25.68 mg/kg in soils with the average of 5.40 mg/kg. Di-(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) had the highest detection frequency (DF = 100%) both in soil and tobacco samples. DEHP was the most abundant of the total PAEs in soil and tobacco samples, with the mean contribution values of 71.0% and 58.8%, respectively. Principal component analysis (PCA) indicates that the major sources of PAEs in the tobacco-soil system were plastic films, fertilizers and pesticides. Health risk assessment suggests that the non-cancer hazard indexes (NCHI) of dimethyl phthalate (DMP), diethyl phthalate (DEP), DBP and di-n-octyl phthalate (DnOP) in all samples for farmers were at acceptable levels (NCHI < 1), and the average carcinogenic hazard indexes (CHI) of butyl benzyl phthalate (BBP) and DEHP for farmers were 3.79 × 10-13 and 8.54 × 10-11 in soils, respectively, 8.23 × 10-13 and 1.95 × 10-11 in tobacco, respectively, which were considered to be very low level (CHI < 10-6). This study provides data on PAEs in tobacco and soils and their health risks which may provide valuable information to aid the management of tobacco cultivation and risk avoidance.

Occurrence, exposure and risk assessment of semi-volatile organic compounds in Chinese homes

Indoor semi-volatile organic compounds (SVOCs) can have a significant impact on human health. Previous studies involved the detection of limited classes of indoor SVOCs in different regions of China. However, overall indoor pollution profiles and the associated health risks via multiple exposure pathways remain unclear. High-throughput screening of SVOCs would help clarify the overall indoor pollution status and identify high-risk pollutants. We collected indoor air and dust samples from 35 Chinese homes and investigated the occurrence of a wide range of SVOCs. Ninety-seven SVOCs including phthalate esters (PAEs), polycyclic aromatic hydrocarbons (PAHs), organophosphate esters, alcohols, fatty acids, phenols, etc., were detected in the air (total concentrations: 0.13-48 μg/m³; median: 3.4 μg/m³) and dust (total concentrations: 120-1500 μg/g; median: 490 μg/g) samples. PAEs were the most abundant, accounting for 55.3 ± 28.6% and 43.4 ± 16.9% of the total SVOC concentrations in the air and dust samples respectively. Human exposure and health risks of 34 SVOCs with detection frequencies >10% were assessed based on inhalation, ingestion and dermal absorption of SVOCs from air and dust by infants and adults. In the case of indoor SVOCs with log K_oa < 9, inhalation and dermal contact with air was >90% for adults and >69% for infants. The following five SVOCs in air samples posed significant non-carcinogenic risks and are listed based on their decreasing risk level: dibutyl phthalate > phenanthrene > stearic acid > methyl palmitate > lauryl alcohol. Four PAHs with 2-4 rings posed potential carcinogenic risks, with phenanthrene exceeding the acceptable risk level of 10^-4. The high risks posed by SVOCs were due to inhalation exposure. Therefore, keeping the air concentrations of SVOCs, especially that of PAEs and PAHs under check would greatly benefit human health in indoor environments.

Simultaneous assessment of organophosphate flame retardants, plasticizers, trace metals, and house dust mite allergens in settled house dust

Settled house dust (SHD) is a reservoir for various contaminants, including endocrine-disrupting chemicals (EDCs), trace metals, and house dust mite allergens. This study aimed to characterize various chemical and biological contaminants in SHD and identify determinants governing the indoor contaminants. In total, 106 SHD samples were collected from 106 houses in Seoul and Gyeonggi Province, Korea, in 2021. Bedding dust samples were collected from 30 of these 106 houses. All participants completed a questionnaire comprised of housing and lifestyle-related factors. The samples were analyzed for 18 organophosphate flame retardants (OPFRs), 16 phthalates, five alternative plasticizers (APs), seven trace metals, and two house dust mite allergens (Dermatophagoides farinae type 1 [Der f1] and Dermatophagoides pteronyssinus type 1 [Der p1]). A multiple regression analysis was conducted to identify the determinants governing the concentrations and profiles of various contaminants. OPFRs, phthalates, APs, and trace metals were detected in all SHD samples, indicating ubiquitous contamination in indoor environments. Among the three EDC groups, APs were detected at the highest concentrations (geometric mean [GM] (geometric standard deviation, [GSD]): 1452 (1.6) μg/g in total), followed by phthalates (GM (GSD): 676 (1.4) μg/g in total) and OPFRs (GM (GSD): 10 (1.4) μg/g in total). Der f1 was detected in all bedding dust samples with significantly higher levels than Der p1 (GM (GSD): 0.1 (1.8) μg/g vs. 1.4 × 10^-3 (2.3) μg/g). The concentrations of OPFRs, plasticizers, and trace metals in SHD were significantly associated with the type and number of electronic appliances and combustion activities. Der f1 was significantly associated with the number of occupants and water penetration. Ventilation, vacuum cleaning, and wet cleaning or dry mopping significantly reduced the levels of most contaminants in SHD. As residents are persistently exposed to a wide array of pollutants, comprehensive and adequate measures are required to prevent potential exposures.

Identification of Phthalates from Artificial Products in Chinese Kindergarten Classrooms and the Implications for Preschool Children's Exposure Assessments

Phthalates are typical chemical pollutants in kindergarten classrooms since numerous artificial products (e.g., polyvinyl chloride (PVC) floorings, soft polymers and plastic toys) that might contain phthalates are widely distributed in kindergarten classrooms. Although Chinese preschool children spend a considerable amount of their waking hours (>8 h/day) in kindergartens, phthalate exposure in such indoor environment has not been given much attention. In this study, the mass fractions of six phthalates in twenty-six artificial products (fifteen flat decoration materials and eleven plastic toys) commonly found in Chinese kindergarten classrooms were measured. Di-2-ethylhexyl phthalate (DEHP) was the most predominant compound in all materials. The emission characteristics of the DEHP from these materials were further investigated. The measured emission characteristics were used for predicting multi-phase DEHP concentrations in kindergarten classrooms by applying a mass transfer model. The modeled concentrations were comparable with those measured in the real environment, indicating that these products might be the major sources of DEHP in Chinese kindergarten classrooms. Preschool children’s exposure to DEHP was found to be 0.42 μg/kg/day in kindergartens under baseline conditions, accounting for 18% of the total exposure to DEHP in Chinese indoor environments.

Prenatal maternal phthalate exposures and trajectories of childhood adiposity from four to twelve years

BACKGROUND/AIM

Adiposity trajectories reflect dynamic process of growth and may predict later life health better than individual measures. Prenatal phthalate exposures may program later childhood adiposity, but findings from studies examining these associations are conflicting. We investigated associations between phthalate biomarker concentrations during pregnancy with child adiposity trajectories.

METHODS

We followed 514 mother-child pairs from the Mexico City PROGRESS cohort from pregnancy through twelve years. We measured concentrations of nine phthalate biomarkers in 2nd and 3rd trimester maternal urine samples to create a pregnancy average using the geometric mean. We measured child BMI z-score, fat mass index (FMI), and waist-to-height ratio (WHtR) at three study visits between four and 12 years of age. We identified adiposity trajectories using multivariate latent class growth modeling, considering BMI z-score, FMI, and WHtR as joint indicators of latent adiposity. We estimated associations of phthalates biomarkers with class membership using multinomial logistic regression. We used quantile g-computation to estimate the potential effect of the total phthalate mixture and assessed effect modification by sex.

RESULTS

We identified three trajectories of child adiposity, a "low-stable", a "low-high", and a "high-high" group. A doubling of the sum of di (2-ethylhexyl) phthalate metabolites (ΣDEHP), was associated with 1.53 (1.08, 2.19) greater odds of being in the "high-high" trajectory in comparison to the "low-stable" group, whereas a doubling in di-isononyl phthalate metabolites (ΣDiNP) was associated with 1.43 (1.02, 2.02) greater odds of being in the "low-high" trajectory and mono (carboxy-isononyl) phthalate (MCNP) was associated with 0.66 (0.45, 97) lower odds of being in the "low-high" trajectory. No sex-specific associations or mixture associations were observed.

CONCLUSIONS

Prenatal concentrations of urinary DEHP metabolites, DiNP metabolites, and MCNP, a di-isodecyl phthalate metabolite, were associated with trajectories of child adiposity. The total phthalate mixture was not associated with early life child adiposity.

Occupational Exposure of Canadian Nail Salon Workers to Plasticizers Including Phthalates and Organophosphate Esters

Personal exposure of nail salon workers to 10 phthalates and 19 organophosphate esters (OPEs) was assessed in 18 nail salons in Toronto, Canada. Active air samplers (n = 60) and silicone passive samplers, including brooches (n = 58) and wristbands (n = 60), were worn by 45 nail salon workers for ∼8 working hours. Diethyl phthalate (median = 471 ng m^-3) and diisobutyl phthalate (337 ng m^-3) were highest in active air samplers. Most abundant OPEs in active air samplers were tris(2-chloroisopropyl)phosphate or TCIPP (303 ng m^-3) and tris(2-chloroethyl)phosphate or TCEP (139 ng m^-3), which are used as flame retardants but have not been reported for use in personal care products or nail salon accessories. Air concentrations of phthalates and OPEs were not associated with the number of services performed during each worker's shift. Within a single work shift, a combined total of 16 (55%) phthalates and OPEs were detected on passive silicone brooches; 19 (66%) were detected on wristbands. Levels of tris(2-chloroisopropyl)phosphate, tris(1,3-dichloro-2-propyl)phosphate or TDCIPP, and triphenyl phosphate or TPhP wristbands were significantly higher than those worn by e-waste workers. Significant correlations (p < 0.05) were found between the levels of some phthalates and OPEs in silicone brooches and wristbands versus those in active air samplers. Stronger correlations were observed between active air samplers versus brooches than wristbands. Sampler characteristics, personal characteristics, and chemical emission sources are the three main factors proposed to influence the use of passive samplers for measuring semi-volatile organic compound exposure.

Phthalates in skin wipes: Distribution, sources, and exposure via dermal absorption

Phthalates, which are widely used in industrial products, can be dermally absorbed into the human body and harm human health. In this study, we measured the levels of phthalates in skin wipes collected from 30 undergraduate volunteers. The body surfaces wiped include the forehead, forearms, hands, back, calves, and insteps. We analyzed the characteristics and possible sources of phthalates on the skin surface and used Monte Carlo simulations to estimate dermal exposure. The mean total dermal exposure was in the range of 0.129-8.25 μg/(kg·day). Seven phthalates were detected, with a detection frequency of 57-100%. Phthalate levels were not significantly different between symmetrical locations, but differed significantly at the same sampling location. The mean dinonyl phthalate (DNP) contribution was the highest on the forehead, back, and forearm. The mean DNP and di (2-n-butoxyethyl) phthalate (DBEP) contributions on hands were the highest and second-highest, respectively. The mean DBEP contribution was the highest on calf and instep. Phthalates level was the maximum on the forehead and instep. Habit and activities can lead to significant differences in phthalate concentrations on the skin surfaces of male and female students. The sum of dermal exposure on the torso, head, and feet perhaps best approximates the total body exposure. To date, information on the dermal exposure and related species of phthalates are limited; therefore, further study is needed.

Brønsted-acid sites promoted degradation of phthalate esters over MnO2: Mineralization enhancement and aquatic toxicity assessment

Advanced oxidation processes (AOPs) are important technologies for aqueous organics removal. Despite organic pollutants can be degraded via AOPs generally, high mineralization of them is hard to achieve. Herein, we synthesized a manganese oxide nanomaterial (H2-OMS-2) with abundant Brønsted-acid sites via ion-exchange of cryptomelane-type MnO₂ (OMS-2), and tested its catalytic performance for the degradation of phthalate esters via peroxymonosulfate (PMS) activation. About 99% of dimethyl phthalate (DMP) at a concentration of 20 mg/L could be degraded within 90 min and 82% of it could be mineralized within 180 min over 0.6 g/L of catalyst and 1.8 g/L of PMS. The catalyst could activate PMS to generate SO₄^-˙ and ·OH as the dominant reactive oxygen species to reach complete degradation of DMP. Especially, the higher TOC removal rate was obtained due to the rich Brønsted-acid sites and surface oxygen vacancies on the catalyst. Kinetics and mechanism study showed that Mn^II/Mn^III might work as the active sites during the catalytic process with a lower reaction energy barrier of 55.61 kJ/mol. Furthermore, the catalyst could be reused for many times through the regeneration of the catalytic ability. The degradation and TOC removal efficiencies were still above 98% and 65% after seven consecutive cycles, respectively. Finally, H2-OMS-2-catalyzed AOPs significantly reduced the organismal developmental toxicity of the DMP wastewater through the investigation of zebrafish model system. The present work, for the first time, provides an idea for promoting the oxidative degradation and mineralization efficiencies of aqueous organic pollutants by surface acid-modification on the catalysts.

Identifying dermal exposure as the dominant pathway of children's exposure to flame retardants in kindergartens

Exploration of multiple sources of brominated (BFRs) and organophosphate flame retardants (OPFRs) for children promotes the understanding of exposure pathways and health risk. 10 BFRs and 9 OPFRs were measured in skin wipes from hands, forehead, and arms of 30 children, and surface wipe samples from sills, toys, desks and floors, and indoor air samples of kindergartens from Xinxiang, China. Higher ∑₉OPFRs concentrations were observed in the forehead (1840 ng/m²), followed by hand (1420 ng/m²) and arm wipes (1130 ng/m²), and the ∑₈BFRs concentrations in forehead, hand and arm wipes were 116, 315 and 165 ng/m², respectively. The total concentration of OPFRs and BFRs in floor wipes (66.1 and 24.5 ng/m²) were lower than those in toy (205 and 535 ng/m²), sill (227 and 30.1 ng/m²) and desk (84.4 and 139 ng/m²) wipes. Concentrations of FRs in forehead wipes were significantly correlated with those in gaseous air (p < 0.05), moderate correlations were found between the hand wipes and surface wipes (p = 0.054). We estimated the daily average dosages (DADs) of children exposure to FRs via multiple pathways. Compared to DADs via inhalation and hand-to-mouth transfer, dermal exposure was determined to be the predominant exposure pathway to ∑₉OPFRs and ∑₈BFRs.

Quantitative filter forensics for semivolatile organic compounds in social housing apartments

Residents from low-income social housing are vulnerable to adverse health effects from indoor air pollution. Particle-bound concentrations of eight phthalates and 12 polycyclic aromatic hydrocarbons (PAHs) in indoor air were measured using quantitative filter forensics with portable air cleaners deployed for three one-week periods from 2015 to 2017. The sample included 143 apartments across seven multi-unit social housing buildings in Toronto, Canada, that went through energy retrofits in 2016. Eight phthalates and six PAHs were found in more than 50% of the apartments in either of the three sampling periods. Di(2-ethylhexyl) phthalate (DEHP) and phenanthrene were the dominant phthalate and PAH, with median concentrations of 146, 143, and 130 ng/m³ and 1.51, 0.58, and 0.76 ng/m³ in the late spring of 2015, and after retrofits in late spring 2017 and winter of 2017, respectively. SVOC concentrations were generally lower after energy retrofits, with significant differences for phenanthrene, fluoranthene, and pyrene. Lower concentrations post-retrofit may be related to less overheating and less need for opening windows. Concentrations of phthalates and PAHs in this study were similar to or higher than those reported in the literature. Results suggest that the use of portable air filters is a promising method to assess concentrations of indoor particle-bound SVOCs.

Indoor exposure to phthalates and polycyclic aromatic hydrocarbons (PAHs) to Canadian children: the Kingston allergy birth cohort

BACKGROUND

Canadian children are widely exposed to phthalates and polycyclic aromatic hydrocarbons (PAHs) from indoor sources. Both sets of compounds have been implicated in allergic symptoms in children.

OBJECTIVE

We characterize concentrations of eight phthalates and 12 PAHs in floor dust from the bedrooms of 79 children enrolled in the Kingston Allergy Birth Cohort (KABC).

METHOD

Floor dust was collected from the bedrooms of 79 children who underwent skin prick testing for common allergens after their first birthday. Data were collected on activities, household, and building characteristics via questionnaire.

RESULTS

Diisononyl phthalate (DiNP) and phenanthrene were the dominant phthalate and PAH with median concentrations of 561 µg/g and 341 ng/g, respectively. Benzyl butyl phthalate (BzBP) and chrysene had the highest variations among all tested homes, ranging from 1-95% to 1-99%, respectively.

SIGNIFICANCE

Some phthalates were significantly associated with product and material use such as diethyl phthalate (DEP) with fragranced products and DiNP and DiDP with vinyl materials. Some PAHs were significantly associated with household characteristics, such as benzo[a]pyrene with smoking, and phenanthrene and fluoranthene with the presence of an attached garage. Socioeconomic status (SES) had positive and negative relationships with some concentrations and some explanatory factors. No significant increases in risk of atopy (positive skin prick test) was found as a function of phthalate or PAH dust concentrations.

Algae bioprocess to deal with cosmetic chemical pollutants in natural ecosystems: A comprehensive review

Elevated demand and extensive exploitation of cosmetics in day-to-day life have hiked up its industrial productions worldwide. Organic and inorganic chemicals like parabens, phthalates, sulfates, and so forth are being applied as constituents towards the formulations, which tend to be the mainspring ecological complication due to their enduring nature and accumulation properties in various sections of the ecosystem. These cosmetic chemicals get accrued into the terrestrial and aquatic systems on account of various anthropogenic activities involving agricultural runoff, industrial discharge, and domestic effluents. Recently, the use of microbes for remediating persistent cosmetic chemicals has gained immense interest. Among different forms of the microbial community being applied as an environmental beneficiary, algae play a vital role in both terrestrial and aquatic ecosystems by their biologically beneficial metabolites and molecules, resulting in the biobenign and efficacious consequences. The use of various bacterial, fungal, and higher plant species has been studied intensely for their bioremediation elements. The bioremediating property of the algal cells through biosorption, bioassimilation, biotransformation, and biodegradation has made it favorable for the removal of persistent and toxic pollutants from the environment. However, the research investigation concerned with the bioremediation potential of the algal kingdom is limited. This review summarizes and provides updated and comprehensive insights into the potential remediation capabilities of algal species against ecologically hazardous pollutants concerning cosmetic chemicals.

Modelling and parameter estimation of diethyl phthalate partitioning behaviour on glass and aluminum surfaces

The knowledge of the partitioning behaviour of semi-volatile organic compounds (SVOCs), such as phthalates, between different materials and their surrounding air is of extreme importance for quantifying levels of human exposure to these compounds, which have been associated with adverse health effects. Phthalates' partitioning behaviour also represents a key property for modelling and assessing polymer degradation mechanisms associated with plasticiser loss. However, the characterisation of phthalates partitioning behaviour has been reported only for a limited number of compounds, mainly involving di-2-ethylhexyl phthalate (DEHP), di-isononyl phthalate (DINP) and di-isodecyl phtahalate (DIDP), while the characterisation of diethyl phthalate (DEP) partitioning has been overlooked. As one of the first plasticisers employed in the production of semi-synthetic plastics produced industrially in the late 19th and early 20th century, DEP plays an important role for understanding stability issues associated with historically significant artefacts in museum collections and archives. Here we show that the partitioning behaviour of DEP between borosilicate glass and aluminum surfaces and their surrounding air can be described by an exponential function of temperature, presenting a model to describe this relationship for the first time. Model parameters are estimated using nonlinear regression from experimental measurements acquired using 109 samples which have been equilibrated at different temperatures between 20 and 80 °C in sealed environments. Measured partition coefficients have been predicted accurately by our proposed model. The knowledge of DEP equilibrium distribution between adsorptive surfaces and neighbouring environments will be relevant for developing improved mathematical descriptions of degradation mechanisms related to plasticiser loss.