Human biomonitoring (HBM) plays a pivotal role in assessing exposure to toxicologically relevant chemicals, with urinary metabolites serving as key indicators. Despite the widespread implementation of HBM programs globally, certain metabolites, such as mercapturic acids (MAs) derived from volatile organic compounds (VOCs), remain understudied in non-occupationally exposed populations. To bridge this data gap, we analyzed 18 MAs in 360 24-h urine samples collected over a time span of 21 years from 2000 to 2021 in Germany. Two LC-MS/MS methods were utilized to quantify MAs in urine samples obtained from the Environmental Specimen Bank. Statistical analyses, including Kruskal-Wallis tests and Spearman correlations, were employed to evaluate temporal trends, sex-specific differences, and correlations between MAs. Quantification rates between 95 and 100% were obtained for 14 of the 18 MAs, with notable variations in concentrations among different metabolites. The most pronounced decrease in MA levels was observed from 2010/2015 to 2019 with a significant trend for 8 MAs, potentially reflecting changes in environmental exposures and regulations. Moreover, significant differences in urinary excretion per 24 h between males and females were observed for several MAs, highlighting the importance of considering sex in exposure assessments. Comprehensive human biomonitoring (HBM) data with regard to the exposure to volatile organic compounds (VOCs) in Europe is lacking. This prompted us to quantify 18 mercapturic acids as urinary VOC metabolites in 360 samples from the Environmental Specimen Bank collected between 2000 and 2021 in Germany. Our study demonstrates the ubiquitous exposure to numerous VOCs of high toxicological relevance, albeit with a decreasing trend over time for most of the metabolites. This emphasizes the need for a broader HBM to better understand the risk of VOC exposure in Germany and more general in Europe.

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.

Butylated hydroxytoluene (BHT) is an antioxidant which is used in a vast array of consumer products. The most sensitive toxicological endpoints of BHT are hepatic enzyme induction and reproductive effects. Because of its wide dispersive use and its potential relevance for human health, BHT was included in the human biomonitoring (HBM) cooperation between the German Federal Ministry for the Environment and the German Chemical Industry Association. An analytical method for the sensitive determination of 3,5‑di‑tert‑butyl‑4‑hydroxybenzoic acid (BHT acid)-an oxidized metabolite of BHT which is excreted in urine-was developed. This method was then applied in several environmental and occupational HBM surveys, and BHT acid was detected in the vast majority of samples. Health-based guidance values as well as reference values for the interpretation of HBM results were derived for BHT acid. Thus, a fine-grained picture of the current state of BHT exposure in different populations in Germany is now available. Uncertainties arise from large variability in the fraction of dose excreted as BHT acid and incomplete understanding of human metabolism, which limits reverse dosimetry and risk assessment, particularly for children.

Human biomonitoring (HBM) has become a crucial tool for assessing exposure to emerging chemicals. We analyzed 250 24-h urine samples from the German Environmental Specimen Bank (ESB), collected between 2000 and 2021, for exposure to diethylamino hydroxybenzoyl hexyl benzoate (DHHB), a UV filter increasingly used in sunscreens. Three major metabolites were examined: 2-(4-diethylamino)-, 2-(4-ethylamino)-, and 2-(4-amino)-2-hydroxybenzoyl)benzoic acid (DHB, EHB, AHB), with detection rates of 18°%, 13°%, and 87°%, respectively. While EHB and DHB were specific to DHHB, AHB suggested other exposure sources, making it unreliable for assessing DHHB exposure. DHB and EHB were first detected in 2012, with increased detection rates thereafter. The median daily intake of 37 ng/kg bw/d was much lower than the derived no-effect level of 2900 mg/kg bw/d, indicating low risk from DHHB exposure. However, since the analyzed ESB samples were collected in winter, they likely reflect exposure from other products and the environment rather than sunscreen-related exposure. Recently, concerns have emerged regarding the DHHB impurity di-n-hexylphthalate (DnHexP), a reproductive toxicant not authorized in the EU. Retrospective analysis of oral DHHB dosing experiments indeed revealed impurity related dose-dependent excretion of DnHexP metabolites (MnHexP, oxidized 5-OH-MnHexP, and 5-oxo-MnHexP). Due to uncertainties in dose allocation, only a rough excretion fraction of 45°% for MnHexP was derived. Our findings suggest that the DHHB impurity DnHexP may contribute to DnHexP exposure in sunscreen users applying products with contaminated DHHB. Given DnHexP's toxicity, this warrants re-assessment of DHHB's safety in cosmetics and enhanced surveillance of both DHHB and DnHexP in HBM studies.

Despite regulatory actions, lead (Pb) exposure remains a major environmental health concern worldwide due to its widespread occurrence and potential adverse effects. The aims of this study were to explore internal Pb exposure in EU citizens, identify its main sociodemographic determinants, and investigate temporal variations over the last decades. Blood Pb data from a total of 17,790 individuals from 9 biomonitoring studies conducted between 2003 and 2019 in four European countries [Belgium (FLEHS I-IV), teenagers and adults; Czech Republic (SZU), children and adults; Spain (BIOAMBIENT.ES), adults; Germany (ESB, GerES IV and V), with all three age groups] were used. The European Human Biomonitoring Initiative (HBM4EU) harmonized and integrated the different datasets. Linear mixed-model analyses were performed to explore exposure determinants related to Pb concentrations. All participants showed detectable blood Pb concentrations, with an overall mean concentration (± standard deviation) of 20.6 (± 16.7) µg/L. In multivariable analyses, older age at recruitment, smoking habit and residence in more urbanized areas were associated with higher Pb levels, whereas more recent sampling year and higher educational level with lower concentrations. After pooled analysis of individual data, no significant differences were found in the Pb levels of the European citizens studied, probably due to the heterogeneity of the studies included. Collaborative efforts between public health agencies, environmental regulators and communities must continue to monitor trends, explore emerging sources of exposure and refine strategies to ensure sustained progress in reducing Pb levels and protecting the health of European population.

Polycyclic aromatic hydrocarbons (PAHs) are persistent environmental pollutants with well-documented associations to adverse health effects, posing significant public health challenges across Europe. Human exposure to 13 urinary PAH metabolites was assessed in a harmonized cohort of European adults aged 20-39, representing diverse geographic regions across Europe: North (Iceland and Denmark), East (Poland and the Czech Republic), South (Croatia and Portugal), and West (France, Germany, Switzerland, and Luxembourg). This study aimed to achieve a unified understanding of PAH exposure by employing stringent participant selection criteria and harmonizing biomarker analyses by utilizing high-quality analytical protocols across multiple laboratories in Europe. Key findings revealed consistently elevated metabolite levels in smokers compared to non-smokers, with naphthalene metabolites dominating the profiles over phenanthrene and fluorene derivatives. Country-specific analyses highlighted Poland as having the highest naphthalene metabolite concentrations, while Luxembourg exhibited elevated pyrene metabolite levels. Urbanization influenced exposure, with slightly higher metabolite concentrations in town populations compared to rural areas. While sex-based stratification revealed no marked differences, gender emerged as a significant covariate in regression models, with women generally displaying higher exposure to naphthalene metabolites. Educational level further stratified exposure, with lower education correlating with increased PAH levels. Multivariate linear regression identified key exposure factors, including sampling season (i.e., summer, winter, autumn, and spring), dietary habits e.g., smoked foods, and proximity to smoke-prone environments. This dataset provides a significant baseline for evaluating the European Commission's Chemicals Strategy for Sustainability (CSS) and underscores the utility of harmonized human biomonitoring studies in informing targeted public health interventions.

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.

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 mu g/L (0.39-9.05 mu g/g crt) and 3.25-46.58 mu g/L (2.12-33.50 mu g/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 mu g/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.

Little is known about exposure determinants of acrylamide (AA), a genotoxic food-processing contaminant, in Europe. We assessed determinants of AA exposure, measured by urinary mercapturic acids of AA (AAMA) and glycidamide (GAMA), its main metabolite, in 3157 children/adolescents and 1297 adults in the European Human Biomonitoring Initiative. Harmonized individual-level questionnaires data and quality assured measurements of AAMA and GAMA (urine collection: 2014–2021), the short-term validated biomarkers of AA exposure, were obtained from four studies (Italy, France, Germany, and Norway) in children/adolescents (age range: 3–18 years) and six studies (Portugal, Spain, France, Germany, Luxembourg, and Iceland) in adults (age range: 20–45 years). Multivariable-adjusted pooled quantile regressions were employed to assess median differences (β coefficients) with 95% confidence intervals (95% CI) in AAMA and GAMA (µg/g creatinine) in relation to exposure determinants. Southern European studies had higher AAMA than Northern studies. In children/adolescents, we observed significant lower AA associated with high socioeconomic status (AAMA:β = − 9.1 µg/g creatinine, 95% CI − 15.8, − 2.4; GAMA: β = − 3.4 µg/g creatinine, 95% CI − 4.7, − 2.2), living in rural areas (AAMA:β = − 4.7 µg/g creatinine, 95% CI − 8.6, − 0.8; GAMA:β = − 1.1 µg/g creatinine, 95% CI − 1.9, − 0.4) and increasing age (AAMA:β = − 1.9 µg/g creatinine, 95% CI − 2.4, − 1.4; GAMA:β = − 0.7 µg/g creatinine, 95% CI − 0.8, − 0.6). In adults, higher AAMA was also associated with high consumption of fried potatoes whereas lower AAMA was associated with higher body-mass-index. Based on this large-scale study, several potential determinants of AA exposure were identified in children/adolescents and adults in European countries.

For the investigation of diseases and other harmful environmental influences (e.g., chemicals) epidemiological studies rely on high quality human samples, among others. Collecting samples and data in the field can pose an enormous challenge to the study team with regard to health protection and occupational safety, especially in the context of a pandemic where there was great uncertainty about the biological risks associated with SARS-CoV-2. The German Environmental Specimen Bank (German ESB) is a key element of environmental and human biomonitoring in Germany with the aim to document and assess trends of human and environmental exposure to chemicals over time and to provide scientific data for policy decision makers. Starting with a pilot study in 1978 human samples are now collected at four sampling locations annually, while sampling is carried out with a highly standardized mobile laboratory since 2013. Due to the corona pandemic 3 of 4 ESB sampling campaigns had to be cancelled in 2020. However, a continuous sampling is crucial to generate current policy relevant data on chemical exposure. Hence, a protection and hygiene concept has been developed including COVID-19 testing with the goal to protect the health of participants and employees during sampling and to meet legal requirements, while sustaining the standardized procedures of sampling and sample preparation. The concept is based on a flexible approach to allow adjustments to changing government regulations and recommendations in the course of the pandemic. By implementing this concept, all samplings were successfully carried out in 2021 & 2022, with the pandemic still ongoing. This paper provides an example of good practice and valuable insights in how to collect human samples during a pandemic.

The fungicide climbazole is mainly used as an anti-dandruff (AD) agent in cosmetics, such as shampoos or other hair care products. Consequently, an exposure of the general population seems likely because many people suffer from dandruff. We have analyzed urine samples from the German Environmental Specimen Bank (ESB) for two specific climbazole biomarkers, namely (OH)2-climbazole and cx–OH–climbazole, in samples collected in the years 2002, 2007, 2012, 2017 and 2022. (OH)2-Climbazole was determined diastereoselectively, hence three analytes are discussed ((OH)2-climbazole 1, (OH)2-climbazole 2 and cx–OH–climbazole). The study population consisted of 300 students (150 male, 150 female) aged between 20 and 29 at the time of sampling from Halle/Saale in Germany. Most samples under scrutiny did not contain any climbazole metabolites in levels above the limit of quantification (LOQ, 0.5 μg/L for either analyte), only in 16 samples at least one analyte could be quantitated. Even the sample with the highest metabolite concentrations (10.23 μg/L (OH)2-climbazole and 2.53 μg/L cx–OH–climbazole) barely reached the urinary concentrations found in an excretion kinetics study after the typical application of a climbazole-containing shampoo in three volunteers. As a result, estimated daily intakes (max. 1.8 μg/kg bw/d) lay below the subchronic NOAEL (15 mg/kg bw/d) and NOEL (5 mg/kg bw/d) by a factor of more than 8300 and 2700, respectively. The evaluation of the climbazole burden of the general population gives valuable insights for the authorities on the effect of legal restrictions.

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.

Controlling and minimising background contamination is crucial for maintaining a high quality of samples in human biomonitoring targeting organic chemicals. We assessed the contamination of three previous types and one newly introduced medical-grade type of sample tubes used for storing human body fluids at the German Environmental Specimen Bank. Aqueous extracts from these tubes were analysed by non-targeted liquid chromatography-high resolution mass spectrometry (LC-HRMS) before and after a dedicated cleaning procedure. After peak detection using MZmine, Bayesian hypothesis testing was used to group peaks into those originating either from instrumental and laboratory background contamination, or actual tube contaminants, based on if their peak height was reduced, increased or not affected by the cleaning procedure. For all four tube types 80-90% of the 2475 peaks (1549 in positive and 926 in negative mode) were assigned to laboratory/instrumental background, which we have to consider as potential sample tube contaminants. Among the tube contaminants, results suggest a considerable difference in the contaminant peak inventory and the absolute level of contamination among the different sample tube types. The cleaning procedure did not affect the largest fraction of peaks (50-70%). For the medical grade tubes, the removal of contaminants by the cleaning procedure was strongest compared to the previous tubes, but in all cases a small fraction increased in intensity after cleaning, probably due to a release of oligomers or additives. The identified laboratory background contaminants were mainly semi-volatile polymer additives such as phthalates and phosphate esters. A few compounds could be assigned solely as tube-specific contaminants, such as N,N-dibutylformamide and several constituents of the oligomeric light stabiliser Tinuvin-622. A cleaning procedure before use is an effective way to standardise the used sample tubes and minimises the background contamination, and therefore increases sample quality and therewith analytical results.

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.

The mycotoxin deoxynivalenol (DON) is a frequently found contaminant in cereals and cereal-based products. As a German contribution to the European Joint Programme HBM4EU, we analysed the total DON concentration (tDON) in 24-h urine samples from the German Environmental Specimen Bank (ESB). In total, 360 samples collected in 1996, 2001, 2006, 2011, 2016, and 2021 from young adults in Muenster (Germany), were measured by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) after enzymatic deconjugation of the glucuronide metabolites.tDON was found in concentrations above the lower limit of quantification (0.3 & mu;g/L) in 99% of the samples. Medians of the measured concentrations and the daily excretion were 4.3 & mu;g/L and 7.9 & mu;g/24 h, respectively. For only nine participants, urinary tDON concentrations exceeded the provisional Human biomonitoring guidance value (HBM GV) of 23 & mu;g/L.Urinary tDON concentrations were significantly higher for male participants. However, 24-h excretion values normalized to the participant's body weight did not exhibit any significant difference between males and females and the magnitude remained unchanged over the sampling years with exception of the sampling year 2001. Daily intakes were estimated from excretion values. Exceedance of the tolerable daily intake (TDI) of 1 & mu;g/kg bw per day was observed for less than 1% of all participants. TDI exceedances were only present in the sampling year 2001 and not in more recent sampling years while exceedance of the HBM guidance value was also observed in 2011 and 2021.

As one of the core elements of the European Human Biomonitoring Initiative (HBM4EU) a human biomonitoring (HBM) survey was conducted in 23 countries to generate EU-wide comparable HBM data. This survey has built on existing HBM capacity in Europe by aligning national or regional HBM studies, referred to as the HBM4EU Aligned Studies. The HBM4EU Aligned Studies included a total of 10,795 participants of three age groups: (i) 3,576 children aged 6-12 years, (ii) 3,117 teenagers aged 12-18 years and (iii) 4,102 young adults aged 20-39 years. The participants were recruited between 2014 and 2021 in 11-12 countries per age group, geographically distributed across Europe. Depending on the age group, internal exposure to phthalates and the substitute DINCH, halogenated and organophosphorus flame retardants, per-and polyfluoroalkyl substances (PFASs), cadmium, bisphenols, polycyclic aromatic hydrocarbons (PAHs), arsenic species, acrylamide, mycotoxins (deoxynivalenol (total DON)), benzophenones and selected pesticides was assessed by measuring substance specific biomarkers subjected to stringent quality control programs for chemical analysis. For substance groups analyzed in different age groups higher average exposure levels were observed in the youngest age group, i.e., phthalates/DINCH in children versus teenagers, acrylamide and pesticides in children versus adults, benzo-phenones in teenagers versus adults. Many biomarkers in teenagers and adults varied significantly according to educational attainment, with higher exposure levels of bisphenols, phthalates, benzophenones, PAHs and acrylamide in participants (from households) with lower educational attainment, while teenagers from house-holds with higher educational attainment have higher exposure levels for PFASs and arsenic. In children, a social gradient was only observed for the non-specific pyrethroid metabolite 3-PBA and di-isodecyl phthalate (DiDP), with higher levels in children from households with higher educational attainment. Geographical variations were seen for all exposure biomarkers. For 15 biomarkers, the available health-based HBM guidance values were exceeded with highest exceedance rates for toxicologically relevant arsenic in teenagers (40%), 3-PBA in children (36%), and between 11 and 14% for total DON, Sigma (PFOA + PFNA + PFHxS + PFOS), bisphenol S and cadmium. The infrastructure and harmonized approach succeeded in obtaining comparable European wide internal exposure data for a prioritized set of 11 chemical groups. These data serve as a reference for comparison at the global level, provide a baseline to compare the efficacy of the European Commission's chemical strategy for sustainability and will give leverage to national policy makers for the implementation of targeted measures.

Starting in 2002, regulations and legislative amendments in Germany focused on the non-smoker protection with several measures to reduce exposure to secondhand tobacco smoke (SHS). The present work aimed to evaluate the relationship between polycyclic aromatic hydrocarbons (PAHs) and SHS exposure and to determine to which extent enforced non-smoking regulations and smoking bans affected the exposure of the non-smoking population in Germany since their implementation in the early 2000s until today. For this purpose, cotinine and selected monohydroxylated PAHs (OH-PAHs) were analyzed by means of (UP)LC-MS/MS in 510 24-h-urine samples of the Environmental Specimen Bank collected over a time span of 24 years from 1995 to 2019. Median urinary cotinine levels were found to steadily and significantly decline by 82% from 1995 to 2019. A significant decrease of urinary 3-hydroxybenzo[a]pyrene (19%), 1-OH-pyrene (39%), 1-naphthol (66%), 1- (17%), 2- (25%), and 3-OH-phenanthrene (22%) was also observed throughout the same time span. The decline in urinary levels of cotinine and several OH-PAHs can most likely be attributed to smoking bans and regulations limiting SHS and PAH exposure. This study therefore emphasizes the relevance of human biomonitoring to investigate the exposure of humans to chemicals of concern, assess the effectiveness of regulatory measures, and help policies to enforce provisions to protect public health.

Human Biomonitoring (HBM) of emerging chemicals gained increasing attention within the EU in recent years. After evaluating the metabolism, we established a new HBM method for ethoxyquin (EQ), a feed additive, which was banned in 2017 due to concerns regarding the possible exposure of the general population to it and its highly toxic precursor p-phenetidine. The method was applied to 250 urine samples from the Environmental Specimen Bank collected between 2000 and 2021. The major metabolite EQI was quantified in the majority of the study samples illustrating the ubiquitous exposure of the non-occupationally exposed population. A rather constant exposure was observed until 2016 with a significant decline from 2016 to 2021. This drop falls within the EU wide ban of the chemical as a feed additive from June 2017 which led to a gradual removal until its complete suspension in June 2020. The daily intake (DI) was evaluated with respect to the reported derived no-effect level (DNEL) to estimate the potential health risks from EQ exposure. The median DI of 0.0181 µg/kg bw/d corresponds to only 0.01 % of the DNEL. Even the observed maxima up to 13.1 µg/kg bw/d only accounted for 10 % of the DNEL. Nevertheless, the values suggest a general exposure with the risk of higher burden in a low fraction of the population. In regard to the EQ associated intake of the carcinogen and suspected mutagen p-phenetidine, this level of exposure cannot be evaluated as safe. The recent decrease and the broad exposure substantiate the need for future HBM campaigns in population representative studies to further investigate the observed reductions, potentially find highly exposed subgroups and clarify the impact of the ban as feed additive on EQ exposure.

The UV filters octocrylene (OC) and 2-ethylhexyl salicylate (EHS) are commonly used in sunscreens and frequently detected in environmental media. However, knowledge on human exposures is scarce.In this human biomonitoring (HBM) study, we analyzed concentrations of exposure biomarkers specific to OC (CPAA, DOCCA, 5OH-OC) and EHS (5OH-EHS, 5oxo-EHS, 5cx-EPS) in 24-h urine samples (n = 420) from the German Environmental Specimen Bank (ESB). These samples were collected from German students (20–29 years; 30 males/30 females per year) between 1996 and 2020 (4-year intervals; collection in winter).We found continuously increasing OC and EHS exposures (Jonckheere-Terpstra; p < 0.001) documented by very few to no samples with concentrations of the most sensitive biomarkers CPAA and 5cx-EPS above the limit of quantification (LOQ) in 1996 (5 % and 0 %, respectively) and reaching 100 % and 93 % above the LOQ in 2016, with median concentrations of 4.79 and 0.071 µg/L, respectively. In 2020, biomarker concentrations slightly decreased to 3.12 µg/L CPAA (97 %>LOQ) and 0.060 µg/L 5cx-EPS (88 %>LOQ). This general trend was confirmed by the other biomarkers, however at lower detection rates. Based on metabolite excretion in the 24-h urine samples and human toxicokinetic data, we calculated maximum daily intakes (DI) of 17 µg/(kg bw * d) OC and 59 µg/(kg bw * d) EHS. Based on a derived no-effect level (DNEL) of 0.8 mg/(kg bw * d), the OC exposures of individuals in our study did not indicate any health risk. Similarly, for EHS all biomarker concentrations were well below the HBM-I values of 12 µg/L 5OH-EHS and 11 µg/L 5cx-EPS.Our data proves the general applicability of specific OC and EHS metabolites for HBM in the general population and shows clearly increasing exposures. Higher (co-)exposures must be expected in populations with increased sunscreen use such as (summer) vacationers, children and outdoor workers.