A genetically encoded fluorescent whole-cell biosensor for real-time detecting estrogenic activities in water samples

Real-time monitoring of estrogenic activity in the aquatic environment is a challenging task. Current biosensors face difficulties due to their limited response speed and environmental tolerance, especially for detecting wastewater, the major source of estrogenic compounds in aquatic environments. To address these difficulties, this study developed a single fluorescent protein (FP) -based whole-cell bacterial biosensor named ER-Light, which was achieved by inserting the sensing domain of the estrogen receptor (ER) into the FP Citrine and expressing it in the periplasm of Escherichia coli. As designed, ER-Light enables the detection of net estrogenic activity in mixtures, represented by estradiol equivalent concentration (EEQ). ER-Light detects EEQ in 40 s with a detection limit of 4.55 × 10-7 μM and a maximum working range of 1.1 × 10-4 μM, demonstrating sufficient response speed, sensitivity, and working range. In addition, the ER-Light can survive and tolerate wastewater effluent. Satisfactory recoveries (91.0 % to 102.1 %) eliminated concerns about the matrix effect of wastewater. EEQs (Not detected-2.9 ×10-5 µM) measured by ER-Light from the effluent of 9 wastewater treatment plants validate its practicality in detecting wastewater. This is the first attempt to integrate ER into FP-based biosensors for environment monitoring. Our findings provide valuable design rules for real-time detection of bioactivity effects in the environment, contributing to the safeguarding of ecological and human health.

Impact of ultraviolet filters and polycyclic aromatic hydrocarbon from recreational activities on water reservoirs in southeast Queensland Australia

Water reservoirs and lakes are gaining popularity for recreation activities as populations increase and green spaces become in high demand. However, these activities may cause contamination to critical water resources. This study investigates the impact of recreational activities on the presence and concentration of polycyclic aromatic hydrocarbons (PAHs) and ultraviolet (UV) filters in drinking water reservoirs in Southeast Queensland, Australia. Polydimethylsiloxane passive samplers were used to monitor 14 lakes over a 3-year period, focusing on seasonal variations and the influence of recreational activities such as petrol-powered boating and swimming. A total of 15 PAHs and six UV filters were detected, with chrysene (97%) and octyl salicylate (34%) being the most prevalent PAH and UV filter, respectively. Polycyclic aromatic hydrocarbon levels were statistically significantly higher in lakes permitting petrol-powered boating, especially during summer (p = 0.005 to 0.05). Lake Maroon and Lake Moogerah were the only sites that showed significantly higher PAH levels in summer (3.9 ± 1.1 and 4.0 ± 1.2 ng L-1, respectively) than winter (1.6 ± 0.61 and 1.5 ± 0.84, respectively). Ultraviolet filters were generally detected in higher levels in lakes allowing swimming, with Lake Moogerah and Lake Sommerset measuring UV filter concentrations of 20 ± 4.1 and 20 ± 11 ng L-1 in summer, respectively. Other lakes that do not permit swimming, such as Lake Maroon and Lake Samsonvale, also exhibited elevated UV filter levels, suggesting illegal swimming. These findings highlight the complexity of PAH and UV filter presence, influenced by multiple factors including lake size, recreational activity type, and seasonal variations. The levels of individual PAHs and UV filters in this study were below established freshwater guidelines. However, when considering their bioaccumulation potential and mixture toxicity, mitigating the impact of these substances on our environment and the organisms within it should be of priority.

An Enhanced Protocol to Expand Human Exposome and Machine Learning-Based Prediction for Methodology Application

The human exposome remains limited due to the challenging analytical strategies used to reveal low-level endocrine-disrupting chemicals (EDCs) and their metabolites in serum and urine. This limits the integrity of the EDC exposure assessment and hinders understanding of their cumulative health effects. In this study, we propose an enhanced protocol based on multi-solid-phase extraction (multi-SPE) to expand human exposome with polar EDCs and metabolites and train a machine learning (ML) model for methodology prediction based on molecular descriptors. The protocol enhanced the measurement of 70 (25%) and 34 (12%) out of 295 well-acknowledged EDCs in serum and urine compared to the hydrophilic-lipophilic balance sorbent alone. In a nontarget analysis of serum and urine from 20 women of childbearing age in a cohort of 498, controlling occupational factors and daily behaviors for high chemical exposure potential, the multi-SPE protocol increased the measurement of 10 (40%) and 16 (53%) target EDCs and identification of 17 (77%) and 70 (36%) nontarget chemicals (confidence ≥ level 3) in serum and urine, respectively. Interestingly, the ML model predicted that the multi-SPE protocol could identify an additional 38% of the most bioactive chemicals. In conclusion, the multi-SPE protocol advances human exposome by expanding the measurement and identification of exposure profiles.

Studying interaction effects on toxicokinetics in zebrafish combining experimental and modelling approaches

Humans and wildlife are exposed to a complex mixture of anthropogenic chemicals of which only a few have been subjected to regulations. Chemical risk assessment is currently based on evaluating single chemicals, which is costly, time-consuming, and neglect toxicokinetic and toxicodynamic mixture effects. This study focused on interaction effects on the absorption, distribution, metabolism and excretion (ADME) processes of selected chemicals representing potential modulators of these processes. Adult female zebrafish (Danio rerio) were exposed to selected mixture of 11 chemicals and bioconcentration factors (BCFs) on tissue level were determined for 9 of them: bisphenol A (BPA), bisphenol AF (BPAF), bisphenol Z (BPZ), triclosan, tribromophenol, pentachlorophenol, heptafluorobutyric acid (PFBA), perfluorobutanesulfonic acid (PFBS), and perfluorooctanesulfonic acid (PFOS). Comparison of BCFs of bisphenols obtained from single chemical exposure experiments versus the current study revealed no statistically significant differences (p > 0.05), implying no mixture effects on kinetics of bisphenols at investigated concentrations. The same conclusion was reached using two physiologically based kinetic (PBK) models, developed for individual bisphenols and per- and polyfluoroalkyl substances (PFAS), showing good model fit for BPA, BPZ, BPAF, and PFOS. To simulate exposure scenarios where kinetic interaction effects may occur through competitive protein binding in blood, a new PBK model was developed. Simulations where zebrafish were dosed with BPA and BPZ, individually, and combined with varying levels of PFOS, showed that competitive binding to serum proteins alter tissue levels of bisphenols when levels of PFOS exceeded 1 μg/L. This indicates that chemicals acting in concert could perturb ADME but only at higher levels or in complex mixtures.

Applying quantitative structure-activity relationship (QSAR) models to extend the mixture toxicity prediction of scrubber water

Marine organisms are constantly exposed to complex chemical mixtures from natural and anthropogenic sources. One source that has raised concerns is the discharge water from ships equipped with exhaust gas cleaning systems, commonly known as scrubbers. During operation, ships with scrubbers discharge large volumes of scrubber water, known to adversely affect marine organisms, into the environment. Scrubber water is highly acidic and contains a complex mixture of contaminants, including metals and polycyclic aromatic hydrocarbons (PAHs), at high concentrations. To assess the effect from these mixtures, critical values for individual mixture components can be determined from ecotoxicological studies and then compared to measured exposure concentrations. However, for several substances identified in scrubber water, for instance many alkylated PAHs, ecotoxicological studies are unavailable, preventing the determination of critical values. In this study, Quantitative Structure-Activity Relationship (QSAR) models have been used to amend and complement experimental data to estimate the mixture toxicity of scrubber water. Our results show that the combined predicted ecotoxicological response of an amended list of 50 substances measured in scrubber water from the substance groups metals (n = 10), PAHs (n = 16) and their alkylated derivatives (n = 24), still underestimates the response observed in whole effluent toxicity tests. This suggests that there are additional substances and/or synergistic effects in the scrubber water mixtures that contribute to the overall toxicity. Thus, to accurately describe the toxicity of scrubber water, measurements and toxicity assessments must extend far beyond the usual suspects of 16 PAHs and a limited selection of metals. Here, QSAR models and advanced chemical screening-based methods are valuable tools for identifying substances of concern.

Novel flame retardants (NFRs) in e-waste: Environmental burdens, health implications, and recommendations for safety assessment and sustainable management

Novel flame retardants (NFRs) have emerged as chemicals of environmental health concern due to their widespread use as an alternative to polybrominated diphenyl ethers (PBDE) in electrical and electronic devices. Humans and ecosystems are under threat because of e-waste recycling procedures that may emit NFRs and other anthropogenic chemicals into the e-waste workplace and the surrounding environment. The individual toxicity of NFRs including novel brominated flame retardants (NBFRs), their combined effects and the underlying mechanisms of toxicity have remained poorly understood. Exposure assessment as well as chemical safety testing should focus on prioritizing N(B)FRs for regulation and management. Here, the occurrence of N(B)FRs in the vicinity and surroundings of e-waste recycling sites are presented. Important knowledge gaps and prospects for a more integrated, harmonized, and mechanistically positioned risk assessment strategy for N(B)FRs as well as possible economically feasible and environmentally sustainable approaches for removing them from complex matrices are highlighted. Overall, data in the ng to µg-ranges of N(B)FR in soil, dust, sediment, water and fish were found. Dust and soil sample concentrations ranged from the low ng to low µg/g range while water concentrations were always in the low ng/L range (∼0.5 to ∼4 ng/L). Concentration in fish was usually in the range of 3- ∼300 ng/g with two substances in the low to medium-high µg/g range (DBDPE, BTBPE). From the 20 N(B)FR analysed in sediment samples only 10 were above detection limit. Most chemicals were found in a low ng/g range.

Miniaturisation of the Daphnia magna immobilisation assay for the reliable testing of low volume samples

International standard test guidelines for the ecotoxicological characterisation of various substances use organisms such as algae, daphnids and fish embryos. These guidelines recommend or use relatively high volumes of water for the process of testing, for example, 200 mL for a complete dose-response relationship in a daphnia assay. However, for various samples such as concentrated extracts from environmental monitoring or leachates from microplastic ageing experiments, the amount of available sample volume is limited, that is, rather in the range of 10-50 mL/biotest. Using the exposure volumes as recommended in test guidelines would not allow to test a range of different concentrations or to repeat tests or use multiple different organismic bioassays. Lower media volumes would allow the testing of more samples (more concentrations per sample, more test repetitions for statistical robustness, etc.) but it may also decrease the possible number of organisms tested in the same volume. Here, we aimed at reducing the test volumes in the acute daphnia assay (using a maximum of 30 mL for a complete dose-response relationship) without impacting animals' sensitivity towards toxicants. A literature review on existing miniaturisation approaches was used as a starting point. Subsequently, assays employing conventional as well as reduced test volumes were compared for 16 selected test substances with a diverse spectrum of lipophilicity. Results showed that there are differences in EC50 between the two approaches, but that these differences were overall only within a range of a factor of two to three. Further, by retrieving EC50 values for the genus Daphnia and 16 test substances from the United States Environmental Protection Agency database, we demonstrated that our results are well in line with the general differences in sensitivities.

High organofluorine concentrations in municipal wastewater affect downstream drinking water supplies for millions of Americans

Wastewater receives per- and polyfluoroalkyl substances (PFAS) from diverse consumer and industrial sources, and discharges are known to be a concern for drinking water quality. The PFAS family includes thousands of potential chemical structures containing organofluorine moieties. Exposures to a few well-studied PFAS, mainly perfluoroalkyl acids (PFAA), have been associated with increased risk of many adverse health outcomes, prompting federal drinking water regulations for six compounds in 2024. Here, we find that the six regulated PFAS (mean = 7 to 8%) and 18 measured PFAA (mean = 11 to 21%) make up only a small fraction of the extractable organofluorine (EOF) in influent and effluent from eight large municipal wastewater treatment facilities. Most of the EOF in influent (75%) and effluent (62%) consists of mono- and polyfluorinated pharmaceuticals. The treatment technology and sizes of the treatment facilities in this study are similar to those serving 70% of the US population. Despite advanced treatment technologies, the maximum EOF removal efficiency among facilities in this work was <25%. Extrapolating our measurements to other large facilities across the United States results in a nationwide EOF discharge estimate of 1.0 to 2.8 million moles F y-1. Using a national model that simulates connections between wastewater discharges and downstream drinking water intakes, we estimate that the sources of drinking water for up to 23 million Americans could be contaminated above regulatory thresholds by wastewater-derived PFAS alone. These results emphasize the importance of further curbing ongoing PFAS sources and additional evaluations of the fate and toxicity of fluorinated pharmaceuticals.

Personal care product use and risk of adult-onset asthma: findings from the Sister Study

BACKGROUND

Personal care products (PCPs) contain endocrine-disrupting chemicals (EDCs) linked to hormonally-sensitive diseases. Population studies have found associations between prenatal EDC exposure and childhood asthma; however, few have investigated adult-onset asthma.

OBJECTIVES

We investigated the associations between commonly used PCPs and the risk of adult-onset asthma in a prospective cohort study of U.S. women.

METHODS

We analyzed 39,408 participants from the Sister Study (2003-2009). The participants self-reported their usage frequency of 41 PCPs in the 12-month period before baseline. Latent classes were used to identify groups with similar usage patterns ('infrequent', 'moderate', 'frequent') within types of products ('beauty', 'everyday hair', 'hygiene', and 'skincare'). Multivariable Cox regression models were used to assess the associations between PCP use and incident adult-onset asthma.

RESULTS

Over an average 12.5-year follow-up, 1,774 incident asthma cases were identified. Compared to infrequent users, moderate (hazard ratio [HR]=1.21 (95% confidence interval (CI):1.07,1.37)) and frequent (HR=1.22 (95%CI:1.08,1.38)) users of beauty products had significantly higher asthma risk. Similar associations were observed for hygiene (moderate: HR=1.14 (95%CI:1.01,1.29) and frequent: HR=1.20 (95%CI:1.06,1.36)) and skincare products (moderate: HR=1.21 (95%CI:1.06,1.38) and frequent: HR=1.20 (95%CI:1.06,1.35)). Several individual everyday hair products (hair spray, hair styling gel/mousse, and pomade or hair grease) were positively associated with asthma risk, but associations were not detected for everyday hair latent classes.

DISCUSSION

Our findings suggest that PCP use potentially contributes to future risk of adult-onset asthma among women. These novel findings reinforce the need for regulation of PCPs and their components to reduce the burden of asthma.

Novel insights into PAHs accumulation and multi-method characterization of interaction between groundwater and surface water in middle Yangtze River: Hydrochemistry, isotope hydrology and fractionation effect

To meet the challenge of water quality protection and management in the middle Yangtze River and understand the accumulation mechanism of PAHs in aquatic complexity systems, caused by hydro-chemical changes, anthropogenic and geological activities, and intensive surface water-groundwater interaction, a comprehensive study is urgently needed. The study investigated the pollution levels, potential sources, accumulation mechanism, and groundwater- surface water interaction of polycyclic aromatic hydrocarbons (PAHs) in wet and dry seasons of the middle Yangtze River. There was no significant difference of PAHs accumulation between wet and dry seasons of the middle Yangtze River. PAHs occurrence in the middle Yangtze River was dominated by the input of tributary. Phenanthrene and Naphthalene were still the dominant species of PAHs. Coal combustion (CC) and biomass burning (BB) were the major contributor for the PAHs occurrence. However, the CC apportionment concentration increased by 6.18 ng·L-1 from wet to dry season, suggesting higher density of coal consumption in dry season. The potential mechanism of PAHs occurrence was demonstrated by the mantel test and structural equation model (SEM). Results revealed that the pollution of the middle Yangtze River could be mainly affected by primary emission in wet and dry seasons due to the significant positive effect between eutrophication levels and PAHs pollution sources. Meanwhile, the difference in redox conditions could directly affect the fate of pollutants (including the valence state transformation of nitrogen and phosphorus). The stronger interaction of groundwater and surface water in dry season was presented by hydrochemistry and isotope hydrology (δ18O and δ2H). The similar result was also evidenced by fractionation effect of PAHs, because more similar behaviors of characteristic pollutants were observed in dry season. Consequently, PAHs can be considered as an effective geochemical tracer and further expanded their toxic effects through the surface water-groundwater interaction.

A cell-based exploration of environmental and health impacts of food waste digestate for its sustainable reutilization

Anaerobic digestion of food waste is increasingly utilized for bioenergy generation, producing a byproduct known as food waste digestate (FWD), which has potential applications as a fertilizer within the circular economy. However, accumulating numerous pollutants in FWD poses significant challenges to environmental management and human health. The complex nature of these pollutants complicates both targeted and non-targeted chemical analyses, making safety evaluations difficult. To address this, we developed a toxicity evaluation protocol based on comprehensive cellular effects to assess the safety profile of FWD. Our study found that human FHC cells were significantly more sensitive to FWD solutions, with 1.2-, 1.8-, and 1.7-fold greater sensitivity than GES-1, HepG2, and HEK293 cells. We identified oxidative stress levels and the activation of the NF-κB signaling pathway as crucial and sensitive indicators of FWD-induced toxicity. Metabolomics analysis revealed that FWD triggered the activation of the inflammatory mediator regulation of the transient receptor potential channels pathway, indicating a cellular response aimed at mitigating damage through immune repair mechanisms. By comprehensively assessing these cellular and molecular indicators, we can better predict the potential human and environmental risks associated with FWD. This knowledge is essential for establishing safety guidelines and appropriate dilution ratios for FWD reutilization, enhancing environmental management practices within a circular economy framework.

Effects of dichlorobenzene, toluene, benzene and formaldehyde chemicals on Drosophila melanogaster mortality

Environmental exposures to volatile organic compound (VOC) mixtures have received increasing attention, yet the risks are under studied. This study aimed to explore the risks of combined exposures to several commonly detected VOCs and to draw attention to the necessity of studying long-term and low-concentration environmental exposure patterns. In this study, we examined the effects of long-term and low-concentration exposures to VOCs like 1,2-dichlorobenzene, benzene, toluene and formaldehyde either alone or in combination on D. melanogaster mortality. A quantitative relationship was established between 1,2-dichlorobenzene concentration and mortality. Additionally, 1,2-dichlorobenzene was more toxic than toluene, and males were more sensitive to 1,2-dichlorobenzene. In cocktail, 1,2-dichlorobenzene + benzene, 1,2-dichlorobenzene acted as an antagonist and interaction type may depend on component concentration. Antagonistic interaction was also found in twice mixture of toluene + benzene + formaldehyde and the degree of antagonism decreased with increasing concentrations of formaldehyde + benzene. The observed interactions and variations in their type or degree relative to mixture component concentrations may be attributed to inter-component metabolic interference and metabolic saturation.

Exploring diet as a source of plasticizers in pregnancy and implications for maternal second-trimester metabolic health

BACKGROUND AND OBJECTIVES

Diet plays critical roles in modulating maternal metabolic health in pregnancy, but is also a source of metabolic-disrupting phthalates and their replacements. We aimed to evaluate whether the effects of better diet quality on favorable maternal metabolic outcomes could be partially explained by lower exposure to phthalates/replacements.

METHODS

At 13 weeks gestation, 295 Illinois women (enrolled 2015-2018) completed a three-month food frequency questionnaire that we used to calculate the Alternative Healthy Eating Index (AHEI)-2010 to assess diet quality. We quantified 19 metabolites, reflecting exposure to 10 phthalates/replacements, in a pool of five first-morning urine samples collected monthly across pregnancy. We measured 15 metabolic biomarkers in fasting plasma samples collected at 17 weeks gestation, which we reduced to five uncorrelated principal components (PCs), representing adiposity, lipids, cholesterol, inflammation, and growth. We used linear regression to estimate associations of diet quality with [1] phthalates/replacements and [2] metabolic PCs, as well as [3] associations of phthalates/replacements with metabolic PCs. We estimated the proportion of associations between diet quality and metabolic outcomes explained by phthalates/replacements using a causal mediation framework.

RESULTS

Overall, every 10-point improvement in AHEI-2010 score was associated with -0.15 (95% CI: -0.27, -0.04) lower adiposity scores, reflecting lower glucose, insulin, C-peptide, leptin, C-reactive protein, but higher adiponectin biomarker levels. Every 10-point increase in diet quality was also associated with 18% (95%CI: 7%, 28%) lower sum of di-2-ethylhexyl terephthalate urinary metabolites (∑DEHTP). Correspondingly, each 18% increase in ∑DEHTP was associated with 0.03 point (95% CI: 0.01, 0.05) higher adiposity PC scores. In mediation analyses, 21% of the inverse relationship between diet quality and adiposity PC scores was explained by lower ∑DEHTP.

CONCLUSIONS

The favorable impact of diet quality on maternal adiposity biomarkers may be partially attributed to lower metabolite concentrations of DEHTP, a plasticizer allowed to be used in food packaging materials.

Aquatic hazard and risk posed by four pesticides detected in waterways discharging to the Great Barrier Reef, Australia: Part 2. Hazard and risk assessment

Pesticide active ingredients (PAIs) are regularly detected in the rivers, creeks, wetlands, and inshore waterways that discharge to the Great Barrier Reef (GBR) lagoon. Pesticide active ingredients detected above ecologically protective concentrations may pose a hazard and risk to aquatic species. The ability to assess this hazard and risk is reliant on the availability of water quality guidelines, which are only available for a limited number of PAIs detected in GBR catchment waterways. Unendorsed guideline values, known as ecotoxicity threshold values (ETVs) were developed in part one of this study for active ingredients in two fungicides (4-hydroxychlorothalonil (fungicide degradate) and carbendazim) and two insecticides (dimethoate and methoxyfenozide) that are commonly detected in GBR catchment waterways. In the current study, the hazard and risk posed by these PAIs was assessed by comparing the ETVs to environmental monitoring data from the Great Barrier Reef Catchment Loads Monitoring Program. Exceedances of the concentrations that should protect 99 % of aquatic species (i.e., PC99) were observed for all four pesticides. Detected concentrations of 4-hydroxychlorothalonil, carbendazim and methoxyfenozide exceeded the PC95 ETV, however no exceedances of the PC95 were observed for dimethoate. The hazard quotient (HQ) method was used to identify high hazard sites across the GBR catchment area. In total, six sites were identified as having concentrations that exceeded the PC95 ETVs. For 4-hydroxychlorothalonil, the risk to aquatic species based on the 95th percentile concentrations ranged from 3 to 13 %, 1 to 8 % for carbendazim and 2 to 8 % for methoxyfenozide. Detected concentrations of carbendazim were two orders of magnitude higher than concentrations that are reported to induce behavioural effects in some fish species. Considering that detected concentrations of three of the four PAIs individually pose a potential risk to aquatic species, their contributions to pesticide mixture toxicity should be further assessed.

The impact of wastewater treatment plants on the composition and toxicity of pollutants in urban rivers in Nanjing, China

Widespread wastewater pollution is one of the biggest challenges threatening the ecological health of rivers. It is crucial to identify the toxic changes of effluents after entering urban rivers as well as the toxic substances in the complex chemical mixtures found in these urban rivers. This study used HepG2 cell line for cytotoxicity test to evaluate the ecological impact of effluents on urban rivers. Water samples were collected from the Xingwu River and Yunliang River in Nanjing, China. The bacterial communities in the lower reaches of urban rivers were altered due to the differences in total nitrogen and nitrate nitrogen. The complex chemical mixtures collected in the urban rivers were divided into 10 fractions, >100 chemicals were screened in each fraction. The substances with LC50 < 1000 mg/L were listed as toxic substances, and the number of toxic substances dominated the toxicity of urban rivers. Our study highlights toxicity as a comprehensive indicator for assessing river pollutants and reveals relationship between the number of toxic substance and river toxicity. These findings have direct implications for the monitoring and management of environmental stressors and the protection of aquatic organisms and human health.

The potential of Gol-e-Gohar iron ore mine airborne dust to induce toxicity in human lung A549 cells

Airborne particulates in iron ore mining are a risk factor for adverse human lung effects. In this study, fine particulates deposited on surfaces of about 1.5 m above the ground and 6 meters from a milling unit of the Gol-e-Gohar iron ore mine were collected through wipe sampling. Dust particles less than 5 µm in diameter were separated with an electronic sieve. Aliquots were prepared from the sieved iron ore dust estimated to be equivalent to respiratory exposure in the iron ore mill in the concentrations of 1, 5, 10, 50, 100, and 250 µg/mL, which were intended to represent equivalent inhaled doses from working one month to a working life (25 years) in the mine. The airborne concentration of respirable particles was about five times the threshold limit value given (TLV®) for iron oxide published by the American Conference of Governmental Industrial Hygienists. The in vitro toxicity range was estimated to be equivalent to an accumulated dose associated with working from one month to a working life in the mine. Treatment of the A549 cells resulted in decreased dehydrogenase activity and cell glutathione content and increased reactive oxygen species (ROS) generation, mitochondrial membrane permeability, and cell apoptosis-necrosis rates. The results of this study revealed the possibility of lung damage at cell doses for respirable airborne iron oxide particles estimated to be equivalent to accumulated lifetime exposures among Gol-e-Gohar miners. Further studies are recommended to investigate the effect of actual contaminants in the workplace on the occurrence of health effects on workers.

The correlation between single and mixed trace elements exposure in systemic lupus erythematosus: A case-control study

BACKGROUND

Recent studies have shown an association between trace elements and systemic lupus erythematosus (SLE), but the relationship between trace elements and SLE is still unclear. This study aims to determine the distribution of plasma trace elements in newly diagnosed SLE patients and the association between these essential and toxic element mixtures and SLE.

METHODS

In total, 110 SLE patients and 110 healthy controls were included. Blood samples were collected. 15 plasma trace elements were quantified using an inductively coupled plasma mass spectrometer (ICP-MS). Multivariate logistic regression, restricted cubic spline (RCS), weighted quantile sum (WQS) regression, quantile g-computation (qgcomp), and Bayesian kernel machine regression (BKMR) are used to analyze the association between single and mixed exposure of elements and SLE.

RESULTS

The logistic regression model shows that, plasma lithium (Li) [OR (95 % CI): 1.963 (1.49-2.586)], vanadium (V) [OR (95 % CI): 2.617(1.645-4.166)] and lead (Pb) [OR (95 % CI): 1.603(1.197-2.145)] were positively correlated with SLE, while selenium (Se) [OR (95 % CI): 0.055(0.019-0.157)] and barium (Ba) [OR (95 % CI): 0.792(0.656-0.957)] had been identified as protective factors for SLE. RCS results showed a non-linear correlation between the elements Li, V, Ni, copper, Se, rubidium and SLE. In addition, WQS regression, qgcomp, and BKMR models consistently revealed significant positive effects of plasma Li and Pb on SLE, as well as significant negative effects of plasma Se.

CONCLUSIONS

Exposure to heavy metals such as Li and Pb is significantly positively correlated with SLE, but Se may be protective factors for SLE. In addition, there is a nonlinear correlation between the elements Li and Se and SLE, and there are complex interactions between the elements. In the future, larger populations and prospective studies are needed to confirm these associations.

Uncovering global risk to human and ecosystem health from pesticides in agricultural surface water using a machine learning approach

Pesticides typically co-occur in agricultural surface waters and pose a potential threat to human and ecosystem health. As pesticide screening in global agricultural surface waters is an immense analytical challenge, a detailed risk picture of pesticides in global agricultural surface waters is largely missing. Here, we create the first global maps of human health and ecological risk from pesticides in agricultural surface waters using random forest models based on 27,411 measurements of 309 pesticides and 30 geospatial parameters. Our global risk maps identify the hotspots, mainly in Southern Asia and Africa, with extensive pesticide use and poor wastewater management infrastructure. We identify 4 and 5 priority pesticides for protecting the human and ecosystem health, respectively. Importantly, we estimate that 305 million people worldwide are at potential health risk associated with the surface-water pesticide mixture exposure, with the vast majority (86%) being in Asia. We further identify the hotspots in the Ganges River basin in India, where more than 170 million people are at potential health risk. As pesticides are increasingly used to ensure the food production due to future population growth and climate change, our findings have implications for raising awareness of pesticide pollution, identifying the hotspots and helping to prioritize testing.

Cytotoxic and Molecular Effects of Soil Extracts from the Agbogbloshie Electronic-Waste Site on Fish and Human Cell Lines

Effect-based methods (EBM) are of growing interest in environmental monitoring programs. Few EBM have incorporated transcriptomics even though these provide a wealth of biological information and can be modeled to yield transcriptomic points of departure (tPODs). The study objectives were to: A) characterize cytotoxic effects of soil extracts on the rainbow trout RTgill-W1 and the human Caco-2 cell lines; B) measure gene expression changes and calculate tPODs; and C) compare in vitro responses to available measures of plastic-related compounds and metals. Extracts were prepared from 35 soil samples collected at the Agbogbloshie E-waste site (Accra, Ghana). Cells were exposed to six soil concentrations (0.3 to 9.4 mg dry weight of extract (eQsed)/ml). Many samples caused cytotoxicity with RTgill cells being more sensitive than Caco-2 cells. Eleven samples were analyzed for transcriptomics in both cell lines, with responses measured in all samples (52 to 5925 differentially expressed genes) even in the absence of cytotoxicity. In RTgill cells there was concordance between cytotoxic measures in tPOD values (spearman = 0.85). Though trends between in vitro measures and contaminant data were observed, more work is needed in this area before definitive conclusions are drawn. Nonetheless, this study helps support ongoing efforts in establishing alternative testing strategies (e.g., alternative to animal methods; toxicogenomics) for the assessment of complex environmental samples.

Location-dependent effect of microplastic leachates on the respiration rate of two engineering mussel species

Microplastics are ubiquitous in the world's oceans and pose serious environmental concerns, including their ingestion and the release of potentially toxic mixtures of intrinsic and extrinsic chemical compounds (i.e. leachates; MPLs). Mussels, as key intertidal bioengineers and filter-feeders are particularly susceptible to both exposure pathways. While the effects of microplastic ingestion have been widely investigated, research on the impacts of MPLs has only recently begun. This study examined the influence of MPLs derived from beached pellets collected in two separate regions, namely France and Portugal, on the respiration rates of two key ecosystem engineers, Mytilus edulis and Mytilus galloprovincialis. Possibly due to distinct mixtures of leached chemicals, unlike Portuguese-MPLs, exposure to French-MPLs significantly decreased the respiration rate of both mussel species. This research provides new insights into the physiological impacts of MPLs on bioengineer species, highlighting the importance of MP source and potential cascading effects at the ecosystem level. While we reported significant effects on mussel respiration after acute MPL exposure, future research should investigate long-term impacts and potential detoxification mechanisms to clarify the effects of MPs on mussel physiological performance and their potential consequences on specie fitness.

Reimagining agrochemical pollution mitigation: Leveraging hormesis for sustainable environmental solutions

Emerging evidence reveals that low doses of stress stimulate, and high doses suppress, organism responses - a phenomenon known as hormesis. Here, we propose a framework for harnessing hormesis principles to optimize agrochemical use and mitigate pollution. We discuss how hormesis can be applied in agrochemical context and highlight challenges and needs beyond scientific research, offering a perspective for sustainable environmental solutions.

PBAT-modified starch blended film extract induces in vitro toxicity in L-02 cells: induction of oxidative stress, inflammation, and modulation of AMPK pathway

PBAT-modified starch blended film are thermoplastic biodegradable materials with good properties and a wide range of applications. In this study, L-02 cells were used as an in vitro toxicity evaluation system for risk assessment of PBAT-modified starch films with migration studies obtained in different food simulants. Determination of total migration and organic matter revealed that the results were in accordance with the standard except for the total organic matter under 95% (v/v) ethanol food simulant which exceeded the standard. The CCK-8 assay showed that these compounds affect the cell viability of L-02 cells. It was observed that the compounds made the cells express increased AST, ALT, TNF-α, IL-6, IL-1β, and ROS, and decreased SOD, GSH, and ATP. In addition, we explored the effect of migration in PBAT-modified starch composites on protein and gene expression levels in L-02 cells using a transcriptomic approach and found that the AMPK signaling pathway was affected. The expression of AMPK signaling pathway-related proteins was detected by Western Blot, and the expression levels of p-AMPK/AMPK were found to be upregulated, and those of p-mTOR/mTOR, SIRT1, PGC-1α, NRF1 and TFAM were downregulated. The above data suggest that the compounds migrating into the PBAT-modified starch film when exposed to food may induce oxidative stress and inflammation in hepatocytes, and may cause damage to hepatocytes through the AMPK pathway.

Quality evaluation parameter and classification model for effluents of wastewater treatment plant based on machine learning

With the growing consensus of emerging pollutants and biological toxicity risks in wastewater treatment plant (WWTP) effluents, traditional water quality management based on general chemical parameters no longer meets the new challenges. Here, a first-hand dataset containing 9 conventional parameters, 22 mental and inorganic ions, 25 biotoxicity parameters, and 54 emerging pollutants from effluents of 176 municipal WWTPs across China were measured. Four clustering algorithms and five classification algorithms were applied to 65 well-performing models to determine a novel evaluation parameter system. A total of 14 parameters were selected by semi-supervised machine learning, including TN, TP, NH4+-N, NO2--N, Se, SO42-, Caenorhabditis elegans body width, 72 hpf zebrafish embryo hatching rate, tetracycline, acetaminophen, gemfibrozil (Lopid), PFBA, PFHxA, and HFPO-DA. These parameters were then used to construct a Healthy Effluent Quality Index model (HEQi). The application efficiency of HEQi was compared with other common methods such as the Water Quality Index (WQI), Fuzzy Synthesized Evaluation (FSE), and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) in classifying 176 effluents. Results implicated that under the new evaluation criteria, the major task in North and Northeast China remains to reduce the conventional parameters, especially NO2--N. However, it is necessary to strengthen the removal of biotoxicity and emerging pollutants in parts of Central and Eastern China. This study offers new methodological tools and scientific insights for improving water quality assessment and safe discharge of wastewater.

A systems-based analysis to rethink the European environmental risk assessment of regulated chemicals using pesticides as a pilot case

A growing body of scientific literature stresses the need to advance current environmental risk assessment (ERA) methodologies and associated regulatory frameworks to better address the landscape-scale and long-term impact of pesticide use on biodiversity and the ecosystem. Moreover, more collaborative and integrative approaches are needed to meet sustainability goals. The One Health approach is increasingly applied by the European Food Safety Authority (EFSA) to support the transition towards safer, healthier and more sustainable food. To this end, EFSA commissioned the development of a roadmap for action to establish a European Partnership for next-generation, systems-based Environmental Risk Assessment (PERA). Here, we summarise the main conclusions and recommendations reported in the 2022 PERA Roadmap. This roadmap highlights that fragmentation of data, knowledge and expertise across regulatory sectors results in suboptimal processes and hinders the implementation of integrative ERA approaches needed to better protect the environment. To advance ERA, we revisited the underlying assumptions of the current ERA paradigm; that chemical risks are generally assessed and managed in isolation with a substance-by-substance, realistic worst-case and tiered approach. We suggest optimising the use of the vast amount of information and expertise available with pesticides as a pilot area. It is recommended to as soon as possible adopt a systems-based approach, i.e. within the current regulatory framework, to spark a step-wise transition towards an ERA framed at a system level of ecological and societal relevance. Tangible systems-based and integrative steps are available. For instance, the rich sources of existing data for prospective and retrospective ERA of pesticides could be used to reality-benchmark existing and new ERA methods. To achieve these goals, collaboration among stakeholders across scientific disciplines and regulatory sectors must be strengthened.

The effect of information about hazardous chemicals in consumer products on behaviour - A systematic review

Exposure to hazardous chemicals in consumer products poses significant risks to personal health and the environment, and the combined effects may be negative even if each individual exposure is low. This necessitates informed and effective policies for risk reduction. This systematic review aims to identify and analyse existing evidence on how consumer preferences, product use, and product disposal are affected by information on harmful chemicals in consumer products and by price interventions. The review is conducted according to the PRISMA 2020 guidelines, synthesises forty-eight scientific articles on the relationship between information and consumer responses. No corresponding studies on the effects of price interventions were found. A large share of the identified articles focused on household chemicals, where warning labels are common, while less has been published on "everyday products" where the presence of hazardous chemicals is less clear to consumers. Effects of information on hazardous chemicals on consumer behaviour are highly contextual and dependent on the type of product, consumer behaviour and what kind of label is used. Warning symbols are effective in communicating a general warning of a potential danger, although consumers often misinterpret specifics regarding the exact nature of that danger or what means should be taken to minimise it. Informational texts are more informative but are also often missed or quickly forgotten. Consumer willingness to pay for safer products is generally positive but low. Additional research on how consumers react to information and price signals on chemical hazards is needed to improve policy design.

Reproductive toxicology: keeping up with our changing world

Reproductive toxicology testing is essential to safeguard public health of current and future generations. Traditional toxicological testing of male reproduction has focused on evaluating substances for acute toxicity to the reproductive system, with fertility assessment as a main endpoint and infertility a main adverse outcome. Newer studies in the last few decades have significantly widened our understanding of what represents an adverse event in reproductive toxicology, and thus changed our perspective of what constitutes a reproductive toxicant, such as endocrine disrupting chemicals that affect fertility and offspring health in an intergenerational manner. Besides infertility or congenital abnormalities, adverse outcomes can present as increased likelihood for various health problems in offspring, including metabolic syndrome, neurodevelopmental problems like autism and increased cancer predisposition, among others. To enable toxicologic studies to accurately represent the population, toxicologic testing designs need to model changing population characteristics and exposure circumstances. Current trends of increasing importance in human reproduction include increased paternal age, with an associated decline of nicotinamide adenine dinucleotide (NAD), and a higher prevalence of obesity, both of which are factors that toxicological testing study design should account for. In this perspective article, we highlighted some limitations of standard testing protocols, the need for expanding the assessed reproductive endpoint by including genetic and epigenetic sperm parameters, and the potential of recent developments, including mixture testing, novel animal models, in vitro systems like organoids, multigenerational testing protocols, as well as in silico modelling, machine learning and artificial intelligence.

Personalized mixture toxicity testing: A proof-of-principle in vitro study evaluating the steroidogenic effects of reconstructed contaminant mixtures measured in blood of individual adults

Chemical risk assessments typically focus on single substances, often overlooking real-world co-exposures to chemical mixtures. Mixture toxicology studies using representative mixtures can reveal potential chemical interactions, but these do not account for the unique chemical profiles that occur in the blood of diverse individuals. Here we used the H295R steroidogenesis assay to screen personalized mixtures of 24 persistent organic pollutants (POPs) for cytotoxicity and endocrine disruption. Each mixture was reconstructed at a human exposure relevant concentration (1×), as well as at 10- and 100-fold higher concentration (10×, 100×) by acoustic liquid handling based on measured blood concentrations in a Swedish cohort. Among the twelve mixtures tested, nine mixtures decreased the cell viability by 4-18%, primarily at the highest concentration. While the median and maximum mixtures based on the whole study population induced no measurable effects on steroidogenesis at any concentration, the personalized mixture from an individual with the lowest total POPs concentration was the only mixture that affected estradiol synthesis (35% increase at the 100× concentration). Mixtures reconstructed from blood levels of three different individuals stimulated testosterone synthesis at the 1× (11-15%) and 10× concentrations (12-16%), but not at the 100× concentration. This proof-of-principle personalized toxicity study illustrates that population-based representative chemical mixtures may not adequately account for the toxicological risks posed to individuals. It highlights the importance of testing a range of real-world mixtures at relevant concentrations to explore potential interactions and non-monotonic effects. Further toxicological studies of personalized contaminant mixtures could improve chemical risk assessment and advance the understanding of human health, as chemical exposome data become increasingly available.

Deep Learning Bridged Bioactivity, Structure, and GC-HRMS-Readable Evidence to Decipher Nontarget Toxicants in Sediments

Identifying causative toxicants in mixtures is critical, but this task is challenging when mixtures contain multiple chemical classes. Effect-based methods are used to complement chemical analyses to identify toxicants, yet conventional bioassays typically rely on an apical and/or single endpoint, providing limited diagnostic potential to guide chemical prioritization. We proposed an event-driven taxonomy framework for mixture risk assessment that relied on high-throughput screening bioassays and toxicant identification integrated by deep learning. In this work, the framework was evaluated using chemical mixtures in sediments eliciting aryl-hydrocarbon receptor activation and oxidative stress response. Mixture prediction using target analysis explained <10% of observed sediment bioactivity. To identify additional contaminants, two deep learning models were developed to predict fingerprints of a pool of bioactive substances (event driver fingerprint, EDFP) and convert these candidates to MS-readable information (event driver ion, EDION) for nontarget analysis. Two libraries with 121 and 118 fingerprints were established, and 247 bioactive compounds were identified at confidence level 2 or 3 in sediment extract using GC-qToF-MS. Among them, 12 toxicants were analytically confirmed using reference standards. Collectively, we present a "bioactivity-signature-toxicant" strategy to deconvolute mixtures and to connect patchy data sets and guide nontarget analysis for diverse chemicals that elicit the same bioactivity.

The dark side of beauty: an in-depth analysis of the health hazards and toxicological impact of synthetic cosmetics and personal care products

Over the past three decades, the popularity of cosmetic and personal care products has skyrocketed, largely driven by social media influence and the propagation of unrealistic beauty standards, especially among younger demographics. These products, promising enhanced appearance and self-esteem, have become integral to contemporary society. However, users of synthetic, chemical-based cosmetics are exposed to significantly higher risks than those opting for natural alternatives. The use of synthetic products has been associated with a variety of chronic diseases, including cancer, respiratory conditions, neurological disorders, and endocrine disruption. This review explores the toxicological impact of beauty and personal care products on human health, highlighting the dangers posed by various chemicals, the rise of natural ingredients, the intricate effects of chemical mixtures, the advent of nanotechnology in cosmetics, and the urgent need for robust regulatory measures to ensure safety. The paper emphasizes the necessity for thorough safety assessments, ethical ingredient sourcing, consumer education, and collaboration between governments, regulatory bodies, manufacturers, and consumers. As we delve into the latest discoveries and emerging trends in beauty product regulation and safety, it is clear that the protection of public health and well-being is a critical concern in this ever-evolving field.

Correlation between environmental pollutant exposure and cardiopulmonary health by serum biomarker analysis in the Swedish elderly population

Persistent organic pollutants (POPs) affect human health through the aryl hydrocarbon receptor (AhR) pathway and are implicated in mitochondrial dysfunction. Using data from the PIVUS study, we investigated the associations of serum AhR ligand (POP)-mediated luciferase activity (AhRL), mitochondrial ATP production inhibiting substances (MIS-ATP), and those affecting reactive oxygen species (MIS-ROS) with several metabolic syndrome (MetS) and cardiopulmonary function parameters. These include insulin resistance (HOMA-IR), inflammation, oxidative stress, and cardiopulmonary variables (FVC, FEV1, LV-EF, CCA distensibility). MIS-ATP showed significant correlations with HOMA-IR and pulmonary functions, indicating its direct impact of MIS-ATP on metabolic and pulmonary health. MIS-ROS correlated with oxidative stress markers and CCA distensibility, suggesting a role in systemic inflammatory responses. This study highlights the intricate relationships between environmental pollutant mixture and cardiopulmonary health in MetS as indicated by biomarkers of POP exposure in the elderly population, suggesting POP exposure may influence MetS onset and progression through mitochondrial dysfunction.

Phthalates and substitute plasticizers: Main achievements from the European human biomonitoring initiative HBM4EU

Phthalates and the substitute plasticizer DINCH belong to the first group of priority substances investigated by the European Human Biomonitoring Initiative (HBM4EU) to answer policy-relevant questions and safeguard an efficient science-to-policy transfer of results. Human internal exposure levels were assessed using two data sets from all European regions and Israel. The first collated existing human biomonitoring (HBM) data (2005-2019). The second consisted of new data generated in the harmonized "HBM4EU Aligned Studies" (2014-2021) on children and teenagers for the ten most relevant phthalates and DINCH, accompanied by a quality assurance/quality control (QA/QC) program for 17 urinary exposure biomarkers. Exposures differed between countries, European regions, age groups and educational levels. Toxicologically derived Human biomonitoring guidance values (HBM-GVs) were exceeded in up to 5% of the participants of the HBM4EU Aligned Studies. A mixture risk assessment (MRA) including five reprotoxic phthalates (DEHP, DnBP, DiBP, BBzP, DiNP) revealed that for about 17% of the children and teenagers, health risks cannot be excluded. Concern about male reproductive health emphasized the need to include other anti-androgenic substances for MRA. Contaminated food and the use of personal care products were identified as relevant exposure determinants paving the way for new regulatory measures. Time trend analyses verified the efficacy of regulations: especially for the highly regulated phthalates exposure dropped significantly, while levels of the substitutes DINCH and DEHTP increased. The HBM4EU e-waste study, however, suggests that workers involved in e-waste management may be exposed to higher levels of restricted phthalates. Exposure-effect association studies indicated the relevance of a range of endpoints. A set of HBM indicators was derived to facilitate and accelerate science-to-policy transfer. Result indicators allow different groups and regions to be easily compared. Impact indicators allow health risks to be directly interpreted. The presented results enable successful science-to-policy transfer and support timely and targeted policy measures.

Influence of humic acid on the bioaccumulation, elimination, and toxicity of PFOS and TBBPA co-exposure in Mytilus unguiculatus Valenciennes

Tetrabromobisphenol A (TBBPA) and Perfluorooctane sulfonate (PFOS) are emerging contaminants which coexist in marine environments, posing significant risks to ecosystems and human health. The behavior of these contaminants in the presence of dissolved organic matter (DOM), specifically the co-contamination of TBBPA and PFOS, is not well understood. The bioaccumulation, distribution, elimination, and toxic effects of TBBPA and PFOS on thick-shell mussels (Mytilus unguiculatus V.), with the absence and presence of humic acid (HA), a typical DOM, were studied. The results showed that the uptake of TBBPA decreased and the uptake of PFOS increased when exposed to 1 mg/L HA. However, at higher concentrations of HA (5 and 25 mg/L), the opposite effect was observed. Combined exposure to HA, TBBPA, and PFOS resulted in oxidative stress in the digestive gland, with the severity of stress dependent on exposure time and HA dose. Histological analysis revealed a positive correlation between HA concentration and tissue damage caused by TBBPA and PFOS. This study provides insights into the influence of HA on the bioaccumulation-elimination patterns and toxicity of TBBPA and PFOS in marine bivalves, offering valuable data for ecological and health risk assessments of combined pollutants in aquatic environments rich in DOM.

The use of effect biomarkers in chemical mixtures risk assessment - Are they still important?

Human epidemiological studies with biomarkers of effect play an invaluable role in identifying health effects with chemical exposures and in disease prevention. Effect biomarkers that measure genetic damage are potent tools to address the carcinogenic and/or mutagenic potential of chemical exposures, increasing confidence in regulatory risk assessment decision-making processes. The micronucleus (MN) test is recognized as one of the most successful and reliable assays to assess genotoxic events, which are associated with exposures that may cause cancer. To move towards the next generation risk assessment is crucial to establish bridges between standard approaches, new approach methodologies (NAMs) and tools for increase the mechanistically-based biological plausibility in human studies, such as the adverse outcome pathways (AOPs) framework. This paper aims to highlight the still active role of MN as biomarker of effect in the evolution and applicability of new methods and approaches in human risk assessment, with the positive consequence, that the new methods provide a deeper knowledge of the mechanistically-based biology of these endpoints.

Innovative analytical methodologies for characterizing chemical exposure with a view to next-generation risk assessment

The chemical burden on the environment and human population is increasing. Consequently, regulatory risk assessment must keep pace to manage, reduce, and prevent adverse impacts on human and environmental health associated with hazardous chemicals. Surveillance of chemicals of known, emerging, or potential future concern, entering the environment-food-human continuum is needed to document the reality of risks posed by chemicals on ecosystem and human health from a one health perspective, feed into early warning systems and support public policies for exposure mitigation provisions and safe and sustainable by design strategies. The use of less-conventional sampling strategies and integration of full-scan, high-resolution mass spectrometry and effect-directed analysis in environmental and human monitoring programmes have the potential to enhance the screening and identification of a wider range of chemicals of known, emerging or potential future concern. Here, we outline the key needs and recommendations identified within the European Partnership for Assessment of Risks from Chemicals (PARC) project for leveraging these innovative methodologies to support the development of next-generation chemical risk assessment.

Influence of ozonation and UV/H2O2 on the genotoxicity of secondary wastewater effluents

The implementation of novel wastewater treatment technologies, including Advanced Oxidation Processes (AOPs) such as ozonation and ultraviolet radiation (UV) combined with hydrogen peroxide (H2O2), can be a promising strategy for enhancing the quality of these effluents. However, during effluent oxidation AOPs may produce toxic compounds that can compromise the water reuse and the receiving water body. Given this possibility, the aim of this study was to evaluate the genotoxic potential of secondary effluents from two different Wastewater Treatment Plants (WWTP) that were subjected to ozonation or UV/H2O2 for periods of 20 (T1) and 40 (T2) minutes. The genotoxic potential was carried out with the Comet assay (for clastogenic damage) and the Micronucleus assay (for clastogenic and aneugenic damage) in HepG2/C3A cell culture (metabolizing cell line). The results of the comet assay revealed a significant increase in tail intensity in the Municipal WWTP (dry period) effluents treated with UV/H2O2 (T1 and T2). MN occurrence was noted across all treatments in both Pilot and Municipal WWTP (dry period) effluents, whereas nuclear buds (NBs) were noted for all Pilot WWTP treatments and UV/H2O2 treatments of Municipal WWTP (dry period). Moreover, the UV/H2O2 (T1) treatment of Municipal WWTP (dry period) exhibited a noteworthy incidence of multiple alterations per cell (MN + NBs). These findings imply that UV/H2O2 treatment demonstrates higher genotoxic potential compared to ozonation. Furthermore, seasonal variations can have an impact on the genotoxicity of the samples. Results of the study emphasize the importance of conducting genotoxicological tests using human cell cultures, such as HepG2/C3A, to assess the final effluent quality from WWTP before its discharge or reuse. This precaution is essential to safeguard the integrity of the receiving water body and, by extension, the biotic components it contains.

Spatial distributions and temporal trends (2009-2020) of chemical mixtures in streams and rivers across Lombardy region (Italy)

Chemical mixtures in the environment are of increasing concern in the scientific community and regulators. Indeed, evidence indicates that aquatic wildlife and humans can be simultaneously and successively exposed to multiple chemicals mainly originating from different anthropic sources by direct uptake from water and indirectly via eating aquatic organisms. This study analyses a large set of sampling data referring to the entire Lombardy region, the most industrialised and at the same time the most important agriculture area in Italy, investigating the presence and potential effects of chemical mixtures in surface water bodies. We enriched and further developed an approach based on a previous work, where the overall mixture toxicity was evaluated for three representative aquatic organisms (algae, Daphnia, fish) using the concentration addition model to combine exposure with ecotoxicological data. The calculation of the mixture toxicity has been realised for two scenarios, namely best- and worst-case scenarios. The former considered only quantified compounds in the monitoring campaign, while the latter also included substances with concentrations below the limit of quantification (LoQ). Differences between the two scenario results established the potential toxicity range. Our findings revealed that differences were minimal when the calculated toxicity in the best-case scenario indicated potential risk and, on the contrary, they suggest that the worst-case scenario is overly conservative; we could also state that including substances with concentrations below the LoQ when calculating the overall toxicity of the mixture is useless and then we focused solely on the best-case scenario. The analysis of spatial and temporal risk trends together with contaminant types and target organisms highlighted specific clusters of contamination. Finally, in several cases, our study found that only few compounds were responsible for the majority of mixture toxicity.

Multi-source exposure and health risks of phthalates among university students in Northeastern China

The endocrine disruptor phthalates (PAEs) are widely used as important chemical additives in a variety of areas around the globe. PAEs are toxic to reproduction and development and may adversely affect the health of adolescents. Risk assessments of exposure to PAEs from different sources are more reflective of actual exposure than single-source assessments. We used personal exposure parameters to estimate the dose of PAEs to 107 university students from six media (including dormitory dust, dormitory air, clothing, food, disposable food containers, and personal care products (PCPs)) and three exposure routes (including ingestion, inhalation, and dermal absorption). Individual factors and lifestyles may affect PAE exposure to varying degrees. Based on a positive matrix factorization (PMF) model, the results indicated that the main sources of PAEs in dust were indoor building materials and plastics, while PCPs and adhesives were the major sources of airborne PAEs. The relative contribution of each source to PAE exposure showed that food and air were the primary sources of dimethyl phthalate (DMP) and dibutyl phthalate (DBP). Air source contributed the most to diethyl phthalate (DEP) exposure, followed by PCPs. Food was the most significant source of diisobutyl phthalate (DiBP), benzyl butyl phthalate (BBP), and bis(2-ethylhexyl) phthalate (DEHP) exposure. Additionally, the exposure of DEHP to dust was not negligible. The ingestion pathway was the most dominant among the three exposure pathways, followed by dermal absorption. The non-carcinogenic risk of PAEs from the six sources was within acceptable limits. DEHP exhibits a low carcinogenic risk. We suggest university students maintain good hygienic and living habits to minimize exposure to PAEs.

Class-specific recognition and monitoring of environmental steroid estrogens in real water systems utilizing aptamer base substitution mutagenesis approach

The same class of environmental steroid estrogens (SEs) with the highest estrogenic activity share the same chemical core structure and are often found together in the environment, posing significant risks to organismal health and environmental safety due to toxicity accumulation. In this study, a novel method for constructing the group-targeting aptasensor was developed to comprehensively analyze SEs. Through artificial intervention base substitution mutagenesis of adjacent bases T13 and C20 of the aptamer-binding domain recognizing 17β-estradiol, combined with docking calculations, the group-targeting SEs-aptamer for class-specific recognition SEs, such as estrone, estradiol, estriol, and ethinylestradiol were obtained. The binding constant of the SEs-aptamer to the SEs was 108 M-1. The established group-targeting SEs aptasensor exhibited high sensitivity within a concentration range from 0.1 to 10 nM and demonstrated strong interference resistance, as well as high stability and wide pH water applicability. It was further applied to analyze real water samples and monitor changes in SEs concentrations during the removal process by Chlorella pyrenoidosa. These successful applications have demonstrated the excellent ability of this aptasensor to monitor SE in the environment. The method offered a new approach and idea for recognizing and detecting the same class of environmental pollutants in complex systems.

Impact of chemical mixtures from wastewater treatment plant effluents on human immune cell activation: An effect-based analysis

BACKGROUND

Humans are exposed to many different chemicals on a daily basis, mostly as chemical mixtures, usually from food, consumer products and the environment. Wastewater treatment plant effluent contains mixtures of chemicals that have been discarded or excreted by humans and not removed by water treatment. These effluents contribute directly to water pollution, they are used in agriculture and may affect human health. The possible effect of such chemical mixtures on the immune system has not been characterized.

OBJECTIVE

The aim of this study was to investigate the effect of extracts obtained from four European wastewater treatment plant effluents on human primary immune cell activation.

METHODS

Immune cells were exposed to the effluent extracts and modulation of cell activation was performed by multi-parameter flow cytometry. Messenger-RNA (mRNA) expression of genes related to immune system and hormone receptors was measured by RT-PCR.

RESULTS

The exposure of immune cells to these extracts, containing 339 detected chemicals, significantly reduced the activation of human lymphocytes, mainly affecting T helper and mucosal-associated invariant T cells. In addition, basophil activation was also altered upon mixture exposure. Concerning mRNA expression, we observed that 12 transcripts were down-regulated by at least one extract while 11 were up-regulated. Correlation analyses between the analyzed immune parameters and the concentration of chemicals in the WWTP extracts, highlighted the most immunomodulatory chemicals.

DISCUSSION

Our results suggest that the mixture of chemicals present in the effluents of wastewater treatment plants could be considered as immunosuppressive, due to their ability to interfere with the activation of immune cells, a process of utmost importance for the functionality of the immune system. The combined approach of immune effect-based analysis and chemical content analysis used in our study provides a useful tool for investigating the effect of environmental mixtures on the human immune response.

Assessment of the contribution of surfactants to mixture toxicity in French surface waters

Surfactants are widely used 'down-the-drain' chemicals with the potential to occur at high concentrations in local water bodies and to be part of unintentional environmental mixtures. Recently, increased regulatory focus has been placed on the impacts of complex mixtures in aquatic environments and the substances that are likely to drive mixture risk. This study assessed the contribution of surfactants to the total mixture pressure in freshwater ecosystems. Environmental concentrations, collated from existing French monitoring data, were combined with estimated ecotoxicological thresholds to calculate hazard quotients (HQ) for each substance, and hazard indices (HI) for each mixture. Two scenarios were investigated to correct for concentrations below the limit of quantification (LOQ) in the dataset. The first (best-case) scenario assumed all values Collapse

Key Words

• Aquatic
• Complex mixtures
• Concentration addition
• Environmental monitoring
• Risk assessment
• Surfactants

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MESH Headings Collapse

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Affiliation(s)

Nathalie Briels ARCHE Consulting, Liefkensstraat 35d, 9032 Gent (Wondelgem), Belgium
Charlotte Nys ARCHE Consulting, Liefkensstraat 35d, 9032 Gent (Wondelgem), Belgium
Karel P J Viaene ARCHE Consulting, Liefkensstraat 35d, 9032 Gent (Wondelgem), Belgium
Frederik Verdonck ARCHE Consulting, Liefkensstraat 35d, 9032 Gent (Wondelgem), Belgium
Erin M Maloney Shell Global Solutions International B.V., Carel van Bylandtlaan 16, 2596 HR Den Haag, the Netherlands
James Dawick Innospec Limited, Innospec Manufacturing Park, Oil G Sites Road Ellesmere Port, Cheshire CH65 4EY, UK
Chiara Maria Vitale Procter & Gamble, Brussels Innovation Centre, Temselaan 100, B-1853 Strombeek-Bever, Belgium
Diederik Schowanek Procter & Gamble, Brussels Innovation Centre, Temselaan 100, B-1853 Strombeek-Bever, Belgium.

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Spatiotemporal Trends Spanning Three Decades Show Toxic Levels of Chemical Contaminants in Marine Mammals

Despite their ban and restriction under the 2001 Stockholm Convention, persistent organic pollutants (POPs) are still widespread and pervasive in the environment. Releases of these toxic and bioaccumulative chemicals are ongoing, and their contribution to population declines of marine mammals is of global concern. To safeguard their survival, it is of paramount importance to understand the effectiveness of mitigation measures. Using one of the world's largest marine mammals strandings data sets, we combine published and unpublished data to examine pollutant concentrations in 11 species that stranded along the coast of Great Britain to quantify spatiotemporal trends over three decades and identify species and regions where pollutants pose the greatest threat. We find that although levels of pollutants have decreased overall, there is significant spatial and taxonomic heterogeneity such that pollutants remain a threat to biodiversity in several species and regions. Of individuals sampled within the most recent five years (2014-2018), 48% of individuals exhibited a concentration known to exceed toxic thresholds. Notably, pollutant concentrations are highest in long-lived, apex odontocetes (e.g., killer whales (Orcinus orca), bottlenose dolphins (Tursiops truncatus), and white-beaked dolphins (Lagenorhynchus albirostris)) and were significantly higher in animals that stranded on more industrialized coastlines. At the present concentrations, POPs are likely to be significantly impacting marine mammal health. We conclude that more effective international elimination and mitigation strategies are urgently needed to address this critical issue for the global ocean health.

Sex-specific association of exposure to a mixture of phenols, parabens, and phthalates with thyroid hormone and antibody levels in US adolescents and adults

Individuals are exposed to multiple phenols, parabens, and phthalates simultaneously since they are important endocrine-disrupting compounds (EDCs) and share common exposure pathways. It is necessary to assess the effects of the co-exposure of these EDCs on thyroid hormones (THs). In this study, data included 704 adolescents and 2911 adults from the 2007-2012 National Health and Nutrition Examination Survey (NHANES). Serum THs measured total triiodothyronine (T3), total thyroxine (T4), free forms of T3 (FT3) and T4 (FT4), thyroid-stimulating hormone (TSH), thyroglobulin (Tg), thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb). And 16 EDCs (3 phenols, 2 parabens, and 11 phthalates) were measured from urine. The relationship between single EDCs and single THs was analyzed using generalized linear regression. And results showed that several EDCs were positively associated with serum T3 and FT3 levels in boys but negatively associated with serum T4 and FT4 levels in girls. And in adults, five EDCs were negatively associated with T3, T4, or FT4. The effects of co-exposure to 16 EDCs on THs were calculated using Bayesian kernel machine regression and quantile-based g-computational modeling, confirmed that co-exposure was related to the increase of T3 in adolescents and the decrease of T4 in both adolescents and adults. Besides, nonlinear and linear relationships were identified between co-exposure and the risk of positive TPOAb and TgAb in girls and adult females, respectively. In conclusion, phenols, parabens, and phthalates as a mixture might interfere the concentrations of THs and thyroid autoantibodies, and the interfering effect varies significantly by sex as well as by age. Further prospective research is warranted to investigate the causal effects and underlying mechanisms of co-exposure on thyroid dysfunction.

Review on new approach methods to gain insight into the feto-maternal interface physiology

Non-human animals represent a large and important feature in the history of biomedical research. The validity of their use, in terms of reproducible outcomes and translational confidence to the human situation, as well as ethical concerns surrounding that use, have been and remain controversial topics. Over the last 10 years, the communities developing microphysiological systems (MPS) have produced new approach method (NAMs) such as organoids and organs-on-a-chip. These alternative methodologies have shown indications of greater reliability and translatability than animal use in some areas, represent more humane substitutions for animals in these settings, and - with continued scientific effort - may change the conduct of basic research, clinical studies, safety testing, and drug development. Here, we present an introduction to these more human-relevant methodologies and suggest how a suite of pregnancy associated feto-maternal interface system-oriented NAMs may be integrated as reliable partial-/full animal replacements for investigators, significantly aid animal-/environmental welfare, and improve healthcare outcomes.

[Disruptors of thyroid hormones: Which consequences for human health and environment?]

Endocrine disruptors (EDs) of chemical origin are the subject of numerous studies, some of which have led to measures aimed at limiting their use and their impact on the environment and human health. Dozens of hormones have been described and are common to all vertebrates (some chemically related messengers have also been identified in invertebrates), with variable roles that are not always known. The effects of endocrine disruptors therefore potentially concern all animal species via all endocrine axes. These effects are added to the other parameters of the exposome, leading to strong, multiple and complex adaptive pressures. The effects of EDs on reproductive and thyroid pathways have been among the most extensively studied over the last 30 years, in a large number of species. The study of the effects of EDs on thyroid pathways and brain development goes hand in hand with increasing knowledge of 1) the different roles of thyroid hormones at cellular or tissue level (particularly developing brain tissue) in many species, 2) other hormonal pathways and 3) epigenetic interactions. If we want to understand how EDs affect living organisms, we need to integrate results from complementary scientific fields within an integrated, multi-model approach (the so-called translational approach). In the present review article, we aim at reporting recent discoveries and discuss prospects for action in the fields of medicine and research. We also want to highlight the need for an integrated, multi-disciplinary approach to studying impacts and taking appropriate action.

Developmental programming: Impact of preconceptional and gestational exposure to a real-life environmental chemical mixture on maternal steroid, cytokine and oxidative stress milieus in sheep

BACKGROUND

Gestational exposure to environmental chemicals (ECs) is associated with adverse, sex-specific offspring health effects of global concern. As the maternal steroid, cytokine and oxidative stress milieus can have critical effects on pregnancy outcomes and the programming of diseases in offspring, it is important to study the impact of real-life EC exposure, i.e., chronic low levels of mixtures of ECs on these milieus. Sheep exposed to biosolids, derived from human waste, is an impactful model representing the ECs humans are exposed to in real-life. Offspring of sheep grazed on biosolids-treated pasture are characterized by reproductive and metabolic disruptions.

OBJECTIVE

To determine if biosolids exposure disrupts the maternal steroid, cytokine and oxidative stress milieus, in a fetal sex-specific manner.

METHODS

Ewes were maintained before mating and through gestation on pastures fertilized with biosolids (BTP), or inorganic fertilizer (Control). From maternal plasma collected mid-gestation, 19 steroids, 14 cytokines, 6 oxidative stress markers were quantified. Unpaired t-test and ANOVA were used to test for differences between control and BTP groups (n = 15/group) and between groups based on fetal sex, respectively. Correlation between the different markers was assessed by Spearman correlation.

RESULTS

Concentrations of the mineralocorticoids - deoxycorticosterone, corticosterone, the glucocorticoids - deoxycortisol, cortisol, cortisone, the sex steroids - androstenedione, dehydroepiandrosterone, 16-OH-progesterone and reactive oxygen metabolites were higher in the BTP ewes compared to Controls, while the proinflammatory cytokines IL-1β and IL-17A and anti-inflammatory IL-36RA were decreased in the BTP group. BTP ewes with a female fetus had lower levels of IP-10.

DISCUSSION

These findings suggest that pre-conceptional and gestational exposure to ECs in biosolids increases steroids, reactive oxygen metabolites and disrupts cytokines in maternal circulation, likely contributors to the aberrant phenotypic outcomes seen in offspring of BTP sheep - a translationally relevant precocial model.

PBT assessment of chemicals detected in effluent of wastewater treatment plants by suspected screening analysis

Wastewater treatment plants (WWTPs) are the major sources of contaminants discharged into downstream water bodies. Profiling the contaminants in effluent of WWTPs is crucial to assess the potential eco-risks toward downstream organisms. To this end, this study investigated the contaminants in effluent of 10 WWTPs locating in 10 cities of Yangtze River delta region of China by suspected screening analysis. Further, the persistence, bioaccumulation, toxicity (PBT) and the characteristics sub-structures of PBT-like chemicals were analyzed. Totally, 704 chemicals including 155 chemical products, 31 food additives, 52 natural substances, 112 personal care products, 123 pesticides, 192 pharmaceuticals, 17 hormones and 22 others were found. The results of PBT analysis suggested that 42 chemicals (5.97% among the detected chemicals in WWTPs) were with PBT property. Among them, 31 contaminants were not reported previously. 9 characteristics sub-structures (N-methyleneisobutylamine, 1-naphthaldehyde, 2,3,3-trimethylcyclohexene, cyclohexanol, N-sec-butyl-n-propylamine, (5E)-2,6-dimethylocta-1,5-diene, 2-ethylphenol, pentadecane and 6-methoxyhexane) were found for PBT-like chemicals. The sub-structures of highly linear alkyl partially explained the significantly higher PBT score for personal care products. Present study provides fundamental information on PBT properties of contaminants in effluent of WWTPs, which will benefit to prioritize contaminants with high concerns in effluent of WWTPs.

The plastic health map: A systematic evidence map of human health studies on plastic-associated chemicals

BACKGROUND

The global production and use of plastic materials has increased dramatically since the 1960s and there is increasing evidence of human health impacts related to exposure to plastic-associated chemicals. There is, however, no comprehensive, regulatory, post-market monitoring for human health effects of plastic-associated chemicals or particles and it is unclear how many of these have been investigated for effects in humans, and therefore what the knowledge gaps are.

OBJECTIVE

To create a systematic evidence map of peer-reviewed human studies investigating the potential effects of exposure to plastic-associated particles/chemicals on health to identify research gaps and provide recommendations for future research and regulation policy.

METHODS

Medline and Embase databases were used to identify peer-reviewed primary human studies published in English from Jan 1960 - Jan 2022 that investigated relationships between exposures to included plastic-associated particles/chemicals measured and detected in bio-samples and human health outcomes. Plastic-associated particles/chemicals included are: micro and nanoplastics, due to their widespread occurrence and potential for human exposure; polymers, the main building blocks of plastic; plasticizers and flame retardants, the two most common types of plastic additives with the highest concentration ranges in plastic materials; and bisphenols and per- or polyfluoroalkyl substances, two chemical classes of known health concern that are common in plastics. We extracted metadata on the population and study characteristics (country, intergenerational, sex, age, general/special exposure risk status, study design), exposure (plastic-associated particle/chemical, multiple exposures), and health outcome measures (biochemical, physiological, and/or clinical), from which we produced the interactive database 'Plastic Health Map' and a narrative summary.

RESULTS

We identified 100,949 unique articles, of which 3,587 met our inclusion criteria and were used to create a systematic evidence map. The Plastic Health Map with extracted metadata from included studies are freely available at https://osf.io/fhw7d/ and summary tables, plots and overall observations are included in this report.

CONCLUSIONS

We present the first evidence map compiling human health research on a wide range of plastic-associated chemicals from several different chemical classes, in order to provide stakeholders, including researchers, regulators, and concerned individuals, with an efficient way to access published literature on the matter and determine knowledge gaps. We also provide examples of data clusters to facilitate systematic reviews and research gaps to help direct future research efforts. Extensive gaps are identified in the breadth of populations, exposures and outcomes addressed in studies of potential human health effects of plastic-associated chemicals. No studies of the human health effects of micro and/or nanoplastics were found, and no studies were found for 26/1,202 additives included in our search that are of known hazard concern and confirmed to be in active production. Few studies have addressed recent "substitution" chemicals for restricted additives such as organophosphate flame retardants, phthalate substitutes, and bisphenol analogues. We call for a paradigm shift in chemical regulation whereby new plastic chemicals are rigorously tested for safety before being introduced in consumer products, with ongoing post-introduction biomonitoring of their levels in humans and health effects throughout individuals' life span, including in old age and across generations.

A critical review on quantitative evaluation of aqueous toxicity in water quality assessment

Conventional chemical techniques have inherent limitations in detecting unknown chemical substances in water. As a result, effect-based methods have emerged as a viable alternative to overcome these limitations. These methods provide more accurate and intuitive evaluations of the toxic effects of water. While numerous studies have been conducted, only a few have been applied to national water quality monitoring. Therefore, it is crucial to develop toxicity evaluation methods and establish thresholds based on quantifying toxicity. This article provides an overview of the development and application of bioanalytical tools, including in vitro and in vivo bioassays. The available methods for quantifying toxicity are then summarized. These methods include aquatic life criteria for assessing the toxicity of a single compound, comprehensive wastewater toxicity testing for all contaminants in a water sample (toxicity units, whole effluent toxicity, the potential ecotoxic effects probe, the potential toxicology method, and the lowest ineffective dilution), methods based on mechanisms and relative toxicity ratios for substances with the same mode of action (the toxicity equivalency factors, toxic equivalents, bioanalytical equivalents), and effect-based trigger values for micropollutants. The article also highlights the advantages and disadvantages of each method. Finally, it proposes potential areas for applying toxicity quantification methods and offers insights into future research directions. This review emphasizes the significance of enhancing the evaluation methods for assessing aqueous toxicity in water quality assessment.

Anti-androgenic activity of novel flame retardants in mixtures: Newly identified contribution from tris(2,3-dibromopropyl) isocyanurate (TDBP-TAZTO)

In recent decades, male infertility has been on the rise, largely attributed to exposure to chemicals with endocrine-disrupting properties. The adverse effects of disrupting androgen actions on the development and reproductive health of children and adolescents have been extensively studied. Flame retardants (FRs), used in consumer products to delay flammability, have been identified as antagonists of the androgen receptor (AR), potentially leading to adverse outcomes in male reproductive health later in life. This study examined the interaction of eight novel FRs with the AR, employing an in vitro AR-dependent luciferase reporter gene assay utilizing MDA-kb2 cells. The investigation revealed the anti-androgenic activity of tris(2,3-dibromopropyl) isocyanurate (TDBP-TAZTO), a frequently detected FR in the environment. Furthermore, TDBP-TAZTO contributed to anti-androgenic activity when combined with six other anti-androgenic FRs. The mixture effects were predicted by three commonly employed models: concentration addition (CA), generalized CA, and independent action, with the CA model showcasing the highest accuracy. This suggests that all FRs act through a similar mechanism, as further confirmed by in silico molecular docking, indicating limited synergy or antagonism. Importantly, in the mixtures, each FR contributed to the induction of anti-androgenic effects at concentrations below their individual effective concentrations in single exposures. This raises concern for public health, especially considering the co-detection of these FRs and their potential co-occurrence with other anti-androgenic chemicals like bisphenols. Therefore, our findings, along with previous research, strongly support the incorporation of combined effects of mixtures in risk assessment to efficiently safeguard population health.