Coordination of chemical analyses under the European Human Biomonitoring Initiative (HBM4EU): Concepts, procedures and lessons learnt

Effects of Turmeric on Manganese-induced Redox Imbalance in Testicular Tissues: Histo-micrometric and Biochemical analyses

Manganese is the most overlooked chemical element, though it is the 5th most abundant metal in earth' crust. Despite being important in the body's mechanisms, bioaccumulation of manganese in living organisms can be noxious. The current study aimed to evaluate the effects of manganese on male mice's reproductive parameters, and turmeric was used as a remedial agent against manganese-induced potential subchronic toxicity. Healthy male mice were distributed into seven groups (n = 10), Control (untreated), Vehicle control; VC-I (0.1 ml of saline solution), Mn-I (5 mg/Kg BW), Mn-II (10 mg/Kg BW), Mn-III (20 mg/Kg BW), Mn + T (20 mg of Mn/Kg +100 mg turmeric/Kg BW) and Vehicle control; VC-II (0.1 ml of olive oil) via oral gavage routinely, once a day. The experiment was continued for 28 days. Before administrations, the antioxidant capacity of turmeric was evaluated via FRAP, TPC & GC-MS assays. Mice were acclimatized for 10 days after dosing, then euthanized and samples (testis & blood) were recovered. Morphological observations showed minute morphological changes in testes as compared to controls. Morphometric analysis revealed average body weight, testis weight and size of Mn-intoxicated mice were reduced remarkably (P ≤ 0.05) in comparison with the control group. Sideways Mn + T group showed non-significant changes in both parameters. Hematological, micrometric findings and serum testosterone, luteinizing hormone and follicle stimulating hormone were significantly different (P ≤ 0.05) in Mn-exposed groups against controls. These alterations were concomitant with histological variations in Mn-treated groups. While such deviations were less obvious in the Mn + T-administered group. The aforesaid findings deduced that the turmeric supplementation manifested improvements in most of the histo-micrometric, hematological, steroidal parameters and enzymatic indices of mice through its antioxidant action.

Plasticizer exposure in Germany from 1988 to 2022: Human biomonitoring data of 20 plasticizers from the German Environmental Specimen Bank

The German Environmental Specimen Bank (ESB) annually archives 24-h urine samples since the early 1980s. In this study, we analyzed 420 of these samples from the years 2014 to 2022 for metabolites of 18 phthalates and two substitutes. We merged the new data with the data from previous measurement campaigns to a combined dataset of 1825 samples covering a 35-year period from 1988 to 2022 to investigate time trends, calculate daily intakes and perform an anti-androgenic mixture risk assessment. With the extended set of 41 biomarkers, we are now able to monitor the exposure to all EU-labelled reprotoxic phthalates. Most phthalate exposures continued to decrease since first measurements in the 80s, with biggest drops for DnBP (96.6 %) and DEHP (90.9 %). DiNP and DiDP, seen on the rise in earlier campaigns, now declined. Exposures to the newly included, reprotoxic phthalates were generally negligible. Regarding mixture risk, 5 % of the highly exposed still exceeded the Hazard Index (HI) of 1 in 2009. In the current measurement campaign only three individuals (0.7 %) exceeded the HI of 1 (with exceedances still driven by DEHP and DnBP).In 2022, 20 % of the individuals still had an HI > 0.2, which we propose as a benchmark for interpreting phthalate mixture risk, considering concurrent exposures to other anti-androgens. Exposure to the substitutes DINCH and DEHTP continues to increase, with daily intakes of DEHTP exceeding those of DEHP since 2018. Compared with the United States (US) National Health and Nutrition Examination Survey (NHANES) phthalate exposures seem to align, except for DEHTP with up to ten times higher levels in the US. Human biomonitoring (HBM) is the ideal tool to capture actual mixture exposures per individual, integrating all external exposure sources and pathways, thus we will continue to use HBM in exposure and risk assessment of phthalates and other (anti-androgenic) chemicals.

Exposure assessment of the European adult population to deoxynivalenol - Results from the HBM4EU Aligned Studies

Mycotoxins are natural toxins produced by fungi that may cause adverse health effects thus constituting a public health concern. Deoxynivalenol (DON), a mycotoxin affecting the immune system and causing intestinal disorders, was selected as a priority under the European Human Biomonitoring Initiative (HBM4EU). Urinary total DON levels (tDON) of 1270 participants from six countries were used to characterize the internal exposure of the adult European population and identify the most relevant determinants of exposure. tDON concentrations' P50 and P95 were in the range of 0.41-10.16 µg/L (0.39-9.05 µg/g crt) and 3.25-46.58 µg/L (2.12-33.50 µg/g crt) respectively. Higher tDON levels were observed for (i) male participants from France and Germany, (ii) samples collected in spring and summer, (iii) participants with a lower educational level, (iv) participants living in rural areas, (v) individuals without a job in France and Luxembourg, while in Portugal higher exposure was observed in working individuals, (vi) individuals with higher consumption of cereals and bread. The proportion of individuals with exposure levels exceeding the HBM-GV of 23 µg/L was 12.3 %, ranging from 0.8 % to 20.7 % in the individual countries. This study on mycotoxins exposure has used post harmonized questionnaire data and validated analytical methodologies for analysis and covered countries representing the four geographical regions of Europe, having produced much needed knowledge on the exposure of the European adult population to deoxynivalenol.

Influence of bisphenol A and its analogues on human gut microbiota composition and metabolic activity: Insights from an in vitro model

Food contamination is a primary route of human exposure to bisphenols (BPs), which are known to affect gut microbiota (GM) and intestinal health. This study comprehensively assessed the impact of bisphenol A (BPA) and three of its substitutes-bisphenol S (BPS), bisphenol F (BPF), and tetramethyl bisphenol F (TMBPF, the monomer of valPure V70) - on the taxonomic and functional profile of human GM using an in vitro model. Human GM was acutely exposed to 1 mM concentrations of these BPs during a 48 h anaerobic cultivation. We first examined the effects of BPA, BPS, BPF, and TMBPF on GM taxonomic and metabolic profiles, mainly focusing on short-chain fatty acids (SCFAs) production. We then evaluated the degradation potential of these BPs by GM and its influence on their estrogenic activity. Finally, we assessed the impact of GM metabolites from BPs-exposed cultures on the viability of intestinal epithelial cells (Caco-2). BPA, BPS, and BPF severely disrupted GM taxonomic composition and metabolite profiles, significantly reducing SCFAs production. In contrast, TMBPF exhibited the least disruptive effects, suggesting it may be a safer alternative. Although the GM did not biotransform the BPs, bioadsorption occurred, with affinity correlating to hydrophobicity in the order of TMBPF > BPA > BPF > BPS. GM reduced the estrogenic activity of BPs primarily through bioadsorption. However, exposure of gut epithelial cells to Post-Culture Supernatants of BPA, BPF, and TMBPF significantly reduced Caco-2 cell viability, indicating the potential formation of harmful GM-derived metabolites and/or a depletion of beneficial GM metabolites.

Exposure to bisphenol A in European women from 2007 to 2014 using human biomonitoring data - The European Joint Programme HBM4EU

BACKGROUND

Bisphenol A (BPA; or 4,4'-isopropylidenediphenol) is an endocrine disrupting chemical. It was widely used in a variety of plastic-based manufactured products for several years. The European Food Safety Authority (EFSA) recently reduced the Tolerable Daily Intake (TDI) for BPA by 20,000 times due to concerns about immune-toxicity.

OBJECTIVE

We used human biomonitoring (HBM) data to investigate the general level of BPA exposure from 2007 to 2014 of European women aged 18-73 years (n = 4,226) and its determinants.

METHODS

Fifteen studies from 12 countries (Austria, Belgium, Denmark, France, Germany, Greece, Israel, Luxembourg, Slovenia, Spain, Sweden, and the United Kingdom) were included in the BPA Study protocol developed within the European Joint Programme HBM4EU. Seventy variables related to the BPA exposure were collected through a rigorous post-harmonization process. Linear mixed regression models were used to investigate the determinants of total urine BPA in the combined population.

RESULTS

Total BPA was quantified in 85-100 % of women in 14 out of 15 contributing studies. Only the Austrian PBAT study (Western Europe), which had a limit of quantification 2.5 to 25-fold higher than the other studies (LOQ=2.5 µg/L), found total BPA in less than 5 % of the urine samples analyzed. The geometric mean (GM) of total urine BPA ranged from 0.77 to 2.47 µg/L among the contributing studies. The lowest GM of total BPA was observed in France (Western Europe) from the ELFE subset (GM=0.77 µg/L (0.98 µg/g creatinine), n = 1741), and the highest levels were found in Belgium (Western Europe) and Greece (Southern Europe), from DEMOCOPHES (GM=2.47 µg/L (2.26 µg/g creatinine), n = 129) and HELIX-RHEA (GM=2.47 µg/L (2.44 µg/g creatinine), n = 194) subsets, respectively. One hundred percent of women in 14 out of 15 data collections in this study exceeded the health-based human biomonitoring guidance value for the general population (HBM-GVGenPop) of 0.0115 µg total BPA/L urine derived from the updated EFSA's BPA TDI. Variables related to the measurement of total urine BPA and those related to the main socio-demographic characteristics (age, height, weight, education, smoking status) were collected in almost all studies, while several variables related to BPA exposure factors were not gathered in most of the original studies (consumption of beverages contained in plastic bottles, consumption of canned food or beverages, consumption of food in contact with plastic packaging, use of plastic film or plastic containers for food, having a plastic floor covering in the house, use of thermal paper…). No clear determinants of total urine BPA concentrations among European women were found. A broader range of data planned for collection in the original questionnaires of the contributing studies would have resulted in a more thorough investigation of the determinants of BPA exposure in European women.

CONCLUSION

This study highlights the urgent need for action to further reduce exposure to BPA to protect the population, as is already the case in the European Union. The study also underscores the importance of pre-harmonizing HBM design and data for producing comparable data and interpretable results at a European-wide level, and to increase HBM uptake by regulatory agencies.

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.

Characterization of organic contaminants in hair for biomonitoring purposes

Biological monitoring is one way to assess human exposure to contaminants. Blood and urine are often used as biological matrices, but hair is an innovative and effective tool for quantifying more biomarkers over a wider exposure window. In order to improve the use of hair in exposure assessment, this article identifies relevant compounds in the literature to investigate hair contamination. Statistical analysis was performed to correlate the physical-chemical properties of the relevant compounds and their concentration levels in hair. Phthalates, pyrethroids and organophosphate flame retardants were chosen for further study of the interpretation of hair measurements for exposure assessment. No significant correlation was found between the average concentration levels in the literature and the physical-chemical properties of the selected compounds. This work also explores the properties of hair and the analytical process that may impact the quantification of organic contaminants in hair. The sample preparation method (sampling, storage, washing) were also studied and adaptations were suggested to improve the existing methods.

Time Patterns in Internal Human Exposure Data to Bisphenols, Phthalates, DINCH, Organophosphate Flame Retardants, Cadmium and Polyaromatic Hydrocarbons in Europe

Human biomonitoring (HBM) data in Europe are often fragmented and collected in different EU countries and sampling periods. Exposure levels for children and adult women in Europe were evaluated over time. For the period 2000-2010, literature and aggregated data were collected in a harmonized way across studies. Between 2011-2012, biobanked samples from the DEMOCOPHES project were used. For 2014-2021, HBM data were generated within the HBM4EU Aligned Studies. Time patterns on internal exposure were evaluated visually and statistically using the 50th and 90th percentiles (P50/P90) for phthalates/DINCH and organophosphorus flame retardants (OPFRs) in children (5-12 years), and cadmium, bisphenols and polycyclic aromatic hydrocarbons (PAHs) in women (24-52 years). Restricted phthalate metabolites show decreasing patterns for children. Phthalate substitute, DINCH, shows a non-significant increasing pattern. For OPFRs, no trends were statistically significant. For women, BPA shows a clear decreasing pattern, while substitutes BPF and BPS show an increasing pattern coinciding with the BPA restrictions introduced. No clear patterns are observed for PAHs or cadmium. Although the causal relations were not studied as such, exposure levels to chemicals restricted at EU level visually decreased, while the levels for some of their substitutes increased. The results support policy efficacy monitoring and the policy-supportive role played by HBM.