Urinary cotinine and exposure to passive smoke in children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

Passive smoking is a preventable and significant cause of many serious health problems, with children being particularly at risk. In the fifth German Environmental Survey (GerES V), conducted from 2014 to 2017, information reflecting the extent of passive smoke exposure in children and adolescents was collected by interview-based questionnaires and human biomonitoring (HBM) analyses of cotinine in urine from 2260 participants, aged 3-17 years. Based on these population-representative data, we describe current passive smoke exposure stratified by different subgroups and identify specific exposure determinants using multivariate logistic regression. The questionnaire data revealed that 42% of children and adolescents lived with at least one smoker in the household. Quantifiable concentrations of cotinine could be detected in 56% of the participants. The overall median concentration of cotinine was 0.2 µg/L, with children and adolescents of low socioeconomic status found to be a group particularly affected by passive smoke with higher cotinine concentrations (median = 1.2 µg/L). In the multiple analysis, the most significant predictor of cotinine levels derived from the questionnaire was passive smoking at home (odds ratio (OR) 13.07 [95CI: 4.65, 36.70]). However, parental smoking and passive smoking among friends and relatives could also be identified as independent factors influencing elevated cotinine levels. The comparison between the previous cycle GerES IV (2003-2006) on 3-14-year-olds and GerES V shows that tobacco smoke exposure of children decreased significantly. This decrease is likely an effect of extensive non-smoker protection laws being enforced 2007-2008 on federal and state level. This is reflected by a halving of urinary cotinine concentrations. Nevertheless, our results indicate that passive smoke is still a relevant source of harmful pollutants for many children and adolescents in Germany, and thus support the need for further efforts to reduce passive smoke exposure, especially in the private environment.

Harmonization of Human Biomonitoring Studies in Europe: Characteristics of the HBM4EU-Aligned Studies Participants.

Human biomonitoring has become a pivotal tool for supporting chemicals' policies. It provides information on real-life human exposures and is increasingly used to prioritize chemicals of health concern and to evaluate the success of chemical policies. Europe has launched the ambitious REACH program in 2007 to improve the protection of human health and the environment. In October 2020 the EU commission published its new chemicals strategy for sustainability towards a toxic-free environment. The European Parliament called upon the commission to collect human biomonitoring data to support chemical's risk assessment and risk management. This manuscript describes the organization of the first HBM4EU-aligned studies that obtain comparable human biomonitoring (HBM) data of European citizens to monitor their internal exposure to environmental chemicals. The HBM4EU-aligned studies build on existing HBM capacity in Europe by aligning national or regional HBM studies. The HBM4EU-aligned studies focus on three age groups: children, teenagers, and adults. The participants are recruited between 2014 and 2021 in 11 to 12 primary sampling units that are geographically distributed across Europe. Urine samples are collected in all age groups, and blood samples are collected in children and teenagers. Auxiliary information on socio-demographics, lifestyle, health status, environment, and diet is collected using questionnaires. In total, biological samples from 3137 children aged 6-12 years are collected for the analysis of biomarkers for phthalates, HEXAMOLL® DINCH, and flame retardants. Samples from 2950 teenagers aged 12-18 years are collected for the analysis of biomarkers for phthalates, Hexamoll® DINCH, and per- and polyfluoroalkyl substances (PFASs), and samples from 3522 adults aged 20-39 years are collected for the analysis of cadmium, bisphenols, and metabolites of polyaromatic hydrocarbons (PAHs). The children's group consists of 50.4% boys and 49.5% girls, of which 44.1% live in cities, 29.0% live in towns/suburbs, and 26.8% live in rural areas. The teenagers' group includes 50.6% girls and 49.4% boys, with 37.7% of residents in cities, 31.2% in towns/suburbs, and 30.2% in rural areas. The adult group consists of 52.6% women and 47.4% men, 71.9% live in cities, 14.2% in towns/suburbs, and only 13.4% live in rural areas. The study population approaches the characteristics of the general European population based on age-matched EUROSTAT EU-28, 2017 data; however, individuals who obtained no to lower educational level (ISCED 0-2) are underrepresented. The data on internal human exposure to priority chemicals from this unique cohort will provide a baseline for Europe's strategy towards a non-toxic environment and challenges and recommendations to improve the sampling frame for future EU-wide HBM surveys are discussed.

The German Environmental Survey for Children and Adolescents 2014-2017 (GerES V) - Study population, response rates and representativeness.

The German Environmental Survey (GerES) is a population-representative, cross-sectional study on environmental exposures of the general population of Germany. GerES has repeatedly been conducted since 1985 by the German Environment Agency (UBA) in close collaboration with the Health Interview and Examination Surveys of the Robert Koch Institute (RKI). In the German Environmental Survey for Children and adolescents 2014-2017 (GerES V) pollutants and other environmental stressors were measured in human samples as well as in the homes of 3- to 17-year-old children and adolescents. Interviews were conducted about health-related behaviors and living conditions. The GerES V basic program encompassed examinations of whole blood, blood plasma, morning urine and drinking water samples, measurements of ultrafine particles and noise levels, comprehensive standardized interviews, and self-administrated questionnaires. Additional modules on volatile organic compounds and aldehydes, particulate matter (PM2.5) in indoor air, organic compounds in drinking water and pollutants in house dust were conducted in subsamples. Potential GerES V participants were identified and attained by the RKI from those participants who were examined and interviewed for the cross-sectional component of the second follow-up to the German Health Interview and Examination Survey for Children and Adolescents (KiGGS Wave 2). The gross sample of GerES V comprised 3031 children and adolescents of which 2294 finally took part in the survey. This equals a total response rate of 75.7 %. Response rates varied, depending on region, type of municipality, age and sex, from 66.0 % to 78.3 %. By calculating individual case weights, discrepancies due to sample design and non-response between the GerES V sample and the whole population could be considered in statistical analysis. Therefore, the representativeness of the GerES V results with regard to age, sex, community size and region was assured.

Lead, cadmium, mercury, and chromium in urine and blood of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

Metals reach humans through food and drinking water intake and inhalation of airborne particles and can have detrimental health effects in particular for children. The metals presented here (lead, cadmium, chromium, and mercury) could lead to toxic effects such as neurotoxicity, mutagenicity, and have been classified as (possible) carcinogens. Using population representative data from the German Environmental Survey 2014-2017 (GerES V) from 3- to 17-year-old children on lead and cadmium in blood (n = 720) and on cadmium, chromium, and mercury in urine (n = 2250) we describe current internal exposure levels, and socio-demographic and substance-specific exposure determinants. Average internal exposure (geometric means) in blood was 9.47 µg/L for lead and below 0.06 µg/L (limit of quantification) for cadmium, and in urine 0.072 µg/L for cadmium, 0.067 µg/L for mercury, and 0.393 µg/L for chromium, respectively. Younger children have higher concentrations of lead and chromium compared to 14-17-year-old adolescents, and boys have slightly higher mercury concentrations than girls. With respect to substance specific determinants, higher lead concentrations emerged in participants with domestic fuel and in non-smoking children with smokers in the household, higher levels of cadmium were associated with smoking and vegetarian diet and higher levels of mercury with the consumption of seafood and amalgam teeth fillings. No specific exposure determinants emerged for chromium. The health based guidance value HBM-I was not exceeded for mercury and for cadmium in urine it was exceeded by 0.6% of the study population. None of the exceedances was related to substantial tobacco smoke exposure. Comparisons to previous GerES cycles (GerES II, 1990-1992; GerES IV, 2003-2006) indicate continuously lower levels.

Glyphosate and aminomethylphosphonic acid (AMPA) in urine of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

Since the 1970s, glyphosate has become the most used herbicide of the world. The general population is ubiquitously exposed to glyphosate. Its long-term toxicity, carcinogenic potential and other health effects are controversially discussed. Even though the possible health impacts of glyphosate are of global concern, no population-wide monitoring of glyphosate was done yet. This study presents the worldwide first population-representative data on glyphosate and its metabolite aminomethylphosphonic acid (AMPA) for children and adolescents. 2144 first-morning void urine samples of 3-17-year-old children and adolescents living in Germany were analysed for concentrations of glyphosate and AMPA in the German Environmental Survey for Children and Adolescents 2014-2017 (GerESV). In 52 % of the samples (46 % for AMPA) the urinary glyphosate concentrations were above the limit of quantification of 0.1 µg/L. The geometric mean concentrations were 0.107 µg/L (0.090 µg/gcreatinine) for glyphosate and 0.100 µg/L (0.085 µg/gcreatinine) for AMPA. No clear association between exposure to glyphosate or AMPA and vegetarian diet or consumption of cereals, pulses, or vegetables could be identified. The low quantification rate and the 95th percentiles for glyphosate and AMPA of around 0.5 µg/L demonstrate an overall low exposure of the young population in Germany.

Pentachlorophenol and nine other chlorophenols in urine of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

Chlorophenols comprise of a large group of chemicals used inter alia for the production of biocides, pharmaceuticals, other industrial products and are used e.g. as antiseptics or wood preservatives due to their biocidal properties. Several of them are classified as toxic to aquatic life and harmful to humans by ingestion, inhalation, or dermal contact, causing skin and eye irritation. Moreover, chlorophenols are possibly carcinogenic to humans. The most prominent chlorophenol - pentachlorophenol - is carcinogenic to humans, was banned in Germany in 1989 and further regulated by the European Commission in 2006 and included in the Stockholm Convention in 2017. Some chlorophenols are persistent in the environment and are also biodegradation products of precursor substances. To evaluate the health-relevance of recent exposure and monitor the effectiveness of regulatory measures, chlorophenols were analysed in the population-representative German Environmental Survey on Children and Adolescents 2014-2017 (GerES V). First-morning void urine samples of 485 3-17-year-old children and adolescents were analysed for ten chlorophenols. Pentachlorophenol was still quantified in 87% of the children and adolescents with a geometric mean (GM) concentration of 0.19 µg/L (0.16 µg/gcrea) and a maximum concentration of 6.7 µg/L (5.4 µg/gcrea). The maximum concentration was well below the health-based guidance value HBM-I of 25 µg/L (20 µg/gcrea). 4-Monochlorophenol was quantified in all samples with a GM concentration of 1.38 µg/L (1.14 µg/gcrea). 2-Monochlorophenol, 2,4-dichlorophenol, and 2,5-dichlorophenol were quantified in 97%, 98%, and 95% of the samples, with GMs of 0.26 µg/L (0.21 µg/gcrea), 0.24 µg/L (0.20 µg/gcrea), and 0.26 µg/L (0.21 µg/gcrea). 2,6-dichlorophenol, 2,3,4-trichlorophenol, and 2,4,5-trichlorophenol were quantified in 17-25% of the samples with GMs below the limit of quantification (LOQ) of 0.1 µg/L 2,4,6-trichlorophenol was quantified in 72% of the samples (GM: 0.13 µg/L, 0.11 µg/gcrea), 2,3,4,6-tetrachlorophenol in 44% of the samples (GM < LOQ). Comparison to previous cycles of GerES revealed substantially lower exposure to most of the chlorophenols in GerES V. Exposure levels found in Germany were comparatively low in contrast to North American results.

Bisphenol A and six other environmental phenols in urine of children and adolescents in Germany - human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

Exposure to environmental phenols such as bisphenol A, benzophenones, 2-phenylphenol, triclosan, and triclocarban is of concern, because of their endocrine disrupting properties and broad application in consumer products. The current body burden of the 3-17-year-old population in Germany to these substances was assessed in first-morning void urine samples (N = 515-516) collected within the population-representative German Environmental Survey for Children and Adolescents 2014-2017 (GerES V). Bisphenol A was the most prominent phenol analysed here, ubiquitously found in almost all samples with a geometric mean (GM) concentration of 1.905 µg/L (1.669 µg/gcreatinine) and a maximum (MAX) urinary concentration of 399 µg/L. Benzophenone-3 and benzophenone-1 were quantified in 35% and 41% of the samples. GM was below the limit of quantification (LOQ) for benzophenone-3 and 0.559 µg/L (0.489 µg/gcrea) for benzophenone-1, MAX concentrations were 845 µg/L and 202 µg/L, respectively. In 16% of the samples triclosan was found in quantifiable amounts resulting in a GM below LOQ and a MAX concentration of 801 µg/L. Benzophenone-8, 2-phenylphenol and triclocarban were quantified in none or only 1% of the samples. Benzophenone-1 and -3 concentrations were found to be associated with frequent application of personal care products. A comparison with the previous cycle of the survey, GerES IV (2003-2006), showed a decrease of urinary bisphenol A concentrations, mainly in young children. Despite this decrease, the concentration of bisphenol A exceeded the human biomonitoring (HBM) value HBM-I of 0.1 mg/L in 0.11% of the samples. For triclosan, all urinary concentrations were well below the HBM-I value of 2 mg/L. To minimise environmental health risks, it is therefore necessary to maintain a further declining trend for bisphenol A and continue monitoring the exposure to environmental phenols, as well as to monitor substitutes such as bisphenol F and S.

Parabens in urine of children and adolescents in Germany - human biomonitoring results of the german environmental survey 2014-2017 (GerES V).

Parabens are antimicrobial preservatives used in a wide range of consumer products such as personal care products, cosmetics, pharmaceuticals, and food. Consequently, the general population is ubiquitously exposed to these substances via dermal absorption, ingestion, and inhalation. Parabens promote estrogenic activity and are hence under assessment as endocrine disrupting substances. Urine samples from 3- to 17-year-old children and adolescents (N = 516) living in Germany were analysed for concentrations of nine parabens in the population representative German Environmental Survey for Children and Adolescents 2014-2017 (GerES V). Detection rates and urinary concentrations of the parabens decreased with increasing length of the alkyl chain. Methyl paraben was quantified in 97% of the samples with a geometric mean (GM) concentration of 7.724 µg/L (6.714 µg/gcreatinine), ethyl paraben was quantified in 69% (GM: 0.943 µg/L and 0.825 µg/gcrea), and n-propyl paraben in 31% (GM: 0.563 µg/L and 0.493 µg/gcrea). Concentrations of iso-propyl paraben, butyl paraben, iso-butyl paraben, and benzyl paraben were below the limit of quantification in most samples. Pentyl paraben and heptyl paraben were not detected in any of the samples. Paraben concentrations in urine were found to be associated with frequent usage of leave-on personal care products and cosmetics. Cumulative exposure to parabens (back-calculated daily intakes, expressed as hazard index) was found to be on a level raising concern in up to 14% of the population, mainly driven by n-propyl paraben, and depending on the level of conservativeness and point-of departures used for calculation.

Benzene metabolite SPMA and acrylamide metabolites AAMA and GAMA in urine of children and adolescents in Germany - human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

Benzene and acrylamide are carcinogenic substances contained inter alia in tobacco smoke. The mercapturic acid metabolites of benzene, N-acetyl-S-phenyl-L-cysteine (SPMA), and of acrylamide, N-acetyl-S-(3-amino-3-oxopropyl)-cysteine (AAMA) and N-acetyl-S-(3-amino-2-hydroxy-3-oxopropyl)-cysteine (GAMA), were analysed in 2260 first-morning void urine samples from children and adolescents aged 3-17 years, participating in the population-representative German Environmental Survey on Children and Adolescents, GerES V 2014-2017. SPMA was detected in 98% of the participants with a geometric mean (GM) of 0.097 µg/L urine. Smokers had about 10-fold higher levels of the benzene metabolite SPMA than non-smokers. The sample comprises of 48 self-reported smokers, mainly in the oldest age group (14-17-year-olds). Second-hand smoke exposure, living near busy or very busy roads, and using domestic fuels for heating were additionally associated with higher benzene metabolite levels. SPMA levels in GerES V were lower compared to levels found in other countries, which in part however may reflect different proportions of smokers. The acrylamide metabolites AAMA and GAMA were detected in 100% of the participants with a GM of 72.6 µg/L urine for AAMA and 15.0 µg/L urine for GAMA. Smoking children and adolescents had about 2.5-fold higher AAMA levels than non-smoking ones. The frequency of consumption of french-fried potatoes and potato crisps consumption was also positively associated with urinary AAMA and GAMA levels. Compared to the urinary AAMA and GAMA levels in Germany and other countries, levels in GerES V tended to be higher than in the few studies reported. The urinary levels of the benzene biomarker SPMA, and the acrylamide biomarkers AAMA and GAMA build the basis to derive reference values for the exposure of children and adolescents in Germany. The results reveal options for exposure reduction mainly in personal choices regarding smoking and diet, but also requiring policy to maintain efforts in non-smoking regulations and improving ambient air quality. Providing these results also to the European HBM Initiative HBM4EU will contribute to gain knowledge on the exposure of the European population, the health impact of carcinogens and thus providing support for substantiated exposure assessment.

Metabolites of 4-methylbenzylidene camphor (4-MBC), butylated hydroxytoluene (BHT), and tris(2-ethylhexyl) trimellitate (TOTM) in urine of children and adolescents in Germany - human biomonitoring results of the German Environmental Survey GerES V (2014-2017).

The UV filter 4-methylbenzylidene camphor (4-MBC), used in cosmetics, the antioxidant butylated hydroxytoluene (BHT), used inter alia as a food additive and in cosmetics, and the plasticizer tris(2-ethylhexyl) trimellitate (TOTM), used mainly in medical devices as substitute for di-(2-ethylhexyl) phthalate (DEHP), are suspected to have endocrine disrupting effects. Human biomonitoring methods that allow for assessing the internal exposure of the general population to these substances were recently developed in a German cooperation to enhance the use of human biomonitoring. First-morning void urine samples from 3- to 17-year-old children and adolescents living in Germany were analysed for metabolites of 4-MBC (N = 447), BHT (N = 2091), and TOTM (N = 431) in the population-representative German Environmental Survey on Children and Adolescents 2014-2017 (GerES V). 4-MBC metabolites were found in quantifiable amounts only in single cases and exposure levels remained well below health-based guidance values. In contrast, ubiquitous exposure to BHT became evident with a geometric mean (GM) urinary concentration of the metabolite BHT acid of 2.346 µg/L (1.989 µg/gcreatinine) and a maximum concentration of 248 µg/L (269 µg/gcrea). The highest GM concentration was found in young children aged 3-5 years, yet no specific sources of exposure could be identified. Also, TOTM metabolites were found in quantifiable amounts only in very few samples. None of these findings could be related to previous hospital treatment or exposure via house dust. The presented results will be the basis to derive reference values for exposure of children and adolescents in Germany to BHT and will facilitate to identify changing exposure levels in the general population.

Alkyl pyrrolidone solvents N-methyl-2-pyrrolidone (NMP) and N-ethyl-2-pyrrolidone (NEP) in urine of children and adolescents in Germany - human biomonitoring results of the German Environmental Survey 2014-2017 (GerESV).

N-methyl-2-pyrrolidone (NMP) and its substitute N-ethyl-2-pyrrolidone (NEP) are aprotic solvents used in many technical applications, but also in carpets, and consumer products such as cleaning agents, and cosmetics. NMP and NEP are classified as reproductive toxicants. As a substance of very high concern (SVHC), NMP is included in the European REACH (Registration, Evaluation, Authorisation of Chemicals) candidate listfor authorisation. NMP and NEP metabolites were measured in more than 2100 urine samples of 3- to 17-year-old children and adolescents, participating in the population-representative German Environmental Survey for Children and Adolescents 2014-2017 (GerESV). The two NMP metabolites 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) and 2-hydroxy-N-methylsuccinimide (2-HMSI) could be detected and quantified in all urine samples, and the two NEP metabolites 5-hydroxy-N-ethylpyrrolidone (5-HNEP) and 2-hydroxy-N-ethylsuccinimide (2-HESI) in 32% and 87% of the urine samples. Geometric mean concentrations were 103.1 µg/L (88.21 µg/gcreatinine) for the sum of NMP metabolites and 11.86 µg/L (10.15 µg/gcreatinine) for the sum of NEP metabolites, thus remaining below the current health-based human biomonitoring values. For NMP, highest exposure was found in young children, but exposure pathways could not be revealed. Exposure to NEP was highest in adolescents and participants with low socio-economic status or migration background. Associations to usage of personal care products suggested the choice of products to have a distinct impact on NEP exposure. The presented data can be used by the German Human Biomonitoring Commission to derive new reference values (RV95) for NMP and NEP for children and adolescents in Germany. This will facilitate to recognise changing exposure levels in this population group in Germany.

Metabolites of the fragrance 2-(4-tert-butylbenzyl)propionaldehyde (lysmeral) in urine of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

The synthetic fragrance 2-(4-tert-butylbenzyl)propionaldehyde, also known as lysmeral, butylphenyl methylpropional, lilial, or lily aldehyde, is widely used in cosmetics, personal care products, laundry detergents, and air fresheners. It is classified as suspected to be harmful to fertility and possibly endocrine disrupting. Its maximum concentration in cosmetics is limited. First-morning void urine samples (N = 2133) were analysed for several metabolites of lysmeral (Chemical Abstract Service (CAS) No.: 80-54-6). Samples were collected in the population-representative German Environmental Survey for Children and Adolescents 2014-2017 (GerES V) from German residents aged 3-17 years. Four main metabolites tert-butylbenzoic acid, lysmerol, lysmerylic acid, and hydroxy-lysmerylic acid were found in quantifiable amounts in 100%, 99%, 40%, and 23% of the samples, respectively, with geometric mean concentrations of 10.21 µg/L (8.658 µg/gcrea) for tert-butylbenzoic acid, 1.528 µg/L (1.296 µg/gcrea) for lysmerol, and below the limit of quantification of 0.2 µg/L and 0.4 µg/L for lysmerylic acid and hydroxy-lysmerylic acid, respectively. Girls had higher urinary concentrations of lysmeral metabolites than boys. Usage of fragrances, fabric softener, and personal care products, especially perfume, was positively associated with urinary concentrations of lysmeral metabolites. Source identification builds a basis to derive proposals for reduction of exposure. These results can also provide the foundation for developing reference values for urinary metabolite concentrations of lysmeral in children and adolescents in Germany that will facilitate recognising future exposure trends.

Metabolites of the substitute plasticiser Di-(2-ethylhexyl) terephthalate (DEHTP) in urine of children and adolescents investigated in the German Environmental Survey GerES V, 2014-2017.

Metabolites of di-(2-ethylhexyl) terephthalate (DEHTP), a substitute for ortho-based phthalate plasticisers like di-(2-ethylhexyl) phthalate (DEHP), were analysed in 2112 first-morning void urine samples from children and adolescents aged 3-17 years, participating in the population representative German Environmental Survey on Children and Adolescents, GerES V 2014-2017. The major metabolite 5cx-MEPTP was detected in all urine samples with a geometric mean (GM) of 7.39 µg/L, with highest levels in the mg/L range. The GM for the other metabolites were 0.55 µg/L for 5OH-MEHTP, 0.54 µg/L for 5oxo-MEHTP and below the limit of quantification (LOQ) for 2cx-MMHTP. As already observed for other plasticisers and their substitutes, the youngest children (3-5 years) had 2-2.5-fold higher urinary DEHTP metabolite levels compared to 14-17 years old adolescents. High urinary levels of DEHTP metabolites were associated with high DEHTP concentrations in house dust. None of the samples analysed exceeded the toxicologically derived German human biomonitoring guidance value (HBM-I-Value) of 1.8 mg/L for 5cx-MEPTP. Comparison with DEHTP levels reported in other HBM studies worldwide confirmed a widespread exposure of children, adolescents and adults, with considerably higher exposures (2.6-7 fold) reported in the United States. In GerES V, exposure data for 12 different phthalates and the phthalate substitute DINCH were generated as well. Together with the data for DEHTP presented in this manuscript, GerES V allows a current and comprehensive overview on the concurrent exposure of German children and adolescents to common plasticisers. Further evaluation of aggregate exposure characteristics shall support efforts to reduce chemical hazard burden from plasticisers in Germany and beyond.

Per- and polyfluoroalkyl substances in blood plasma - Results of the German Environmental Survey for children and adolescents 2014-2017 (GerES V).

The 5th cycle of the German Environmental Survey (GerES V) investigated the internal human exposure of children and adolescents aged 3-17 years in Germany to per- and polyfluoroalkyl substances (PFAS). The fieldwork of the population-representative GerES V was performed from 2014 to 2017. In total, 1109 blood plasma samples were analysed for 12 PFAS including perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorohexane sulfonic acid (PFHxS). PFOS was quantified in all and PFOA in almost all samples, demonstrating ubiquitous exposure. The highest geometric mean concentrations measured were 2.49 ng/mL for PFOS, followed by PFOA (1.12 ng/mL) and PFHxS (0.36 ng/mL), while concentrations of other PFAS were found in much lower concentrations. The 95th percentile levels of PFOS and PFOA were 6.00 and 3.24 ng/mL, respectively. The results document a still considerable exposure of the young generation to the phased out chemicals PFOS and PFOA. The observed exposure levels vary substantially between individuals and might be due to different multiple sources. The relative contribution of various exposure parameters such as diet or the specific use of consumer products need to be further explored. Although additional investigations on the time trend of human exposure are warranted, GerES V underlines the need for an effective and sustainable regulation of PFAS as a whole.

2-Mercaptobenzothiazole in urine of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

2-Mercaptobenzothiazole (2-MBT) is widely used as a vulcanisation accelerator and is contained in many products made from natural rubber, e.g. car tires. Additionally, it is used as a fungicide in paint or fibre. Systemically human exposure to 2-MBT can occur via dermal and oral uptake or inhalation. Locally, 2-MBT can cause skin sensitisation. The International Agency for Research on Cancer (IARC) classified 2-MBT as probably carcinogenic to humans. 516 urine samples of 3- to 17-year-old children and adolescents living in Germany were analysed for the concentration of 2-MBT in the population representative German Environmental Survey for Children and Adolescents 2014-2017 (GerES V). 2-MBT was quantified above the limit of quantification (LOQ) of 1.0 µg/L in 50% of the 516 samples analysed. The geometric mean of urinary 2-MBT concentration was 1.018 µg/L and 0.892 µg/gcreatinine, the arithmetic mean was 1.576 µg/L (1.351 µg/gcrea). The median concentration was below the LOQ. Analyses of subgroups revealed higher 2-MBT concentrations in children aged 3-5 years compared to 14- to 17-year-old adolescents. All urinary 2-MBT concentrations were well below the health-based guidance value HBM-I for children of 4.5 µg/L. Therefore, current exposure levels are - according to current knowledge - not of concern. For the first time, reference values can be derived for 2-MBT for children and adolescents in Germany. This will facilitate to recognise changing exposure levels in this population group in Germany and identification of unusually high exposures.

The methylisothiazolinone and methylchloroisothiazolinone metabolite N-methylmalonamic acid (NMMA) in urine of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

Mixtures of methylisothiazolinone and methylchloroisothiazolinone are used as biocides in cosmetics, cleaning agents, and water-based paint. A biomonitoring method to evaluate exposure to these compounds was developed using N-methylmalonamic acid (NMMA), the main metabolite of both, methylisothiazolinone and methylchloroisothiazolinone, as the exposure biomarker. First-morning void urine samples (N = 2078) of 3- to 17-year-old children and adolescents living in Germany were analysed for concentrations of NMMA in the population representative German Environmental Survey for Children and Adolescents GerES V (2014-2017). NMMA was quantified in almost all samples, with a geometric mean concentration of 6.245 µg/L (5.303 µg/gcrea) and a 95th percentile of 15.0 µg/L (12.6 µg/gcrea). Urinary concentrations could not be related to self-reported application of specific cleaning agents or personal care products, leaving potential, specific sources of exposure unrevealed as most products relevant for isothiazolinone exposure are used ubiquitously. For the first time, reference values can be derived for urinary NMMA for children and adolescents in Germany, facilitating a more substantiated exposure assessment.

Polycyclic aromatic hydrocarbons (PAH) in urine of children and adolescents in Germany - human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

Polycyclic aromatic hydrocarbons (PAH) mainly originate from incomplete combustion of organic materials and are, among other sources, found in traffic emissions, smoked or barbecued food, leafy vegetables, and tobacco smoke. Some PAH or their metabolites are hazardous for health and classified as carcinogenic, mutagenic, or toxic to reproduction. Urine samples from 3- to 17-year-old children and adolescents living in Germany were analysed for concentrations of metabolites of the PAH fluorene, naphthalene, phenanthrene, and pyrene in the population-representative German Environmental Survey for Children and Adolescents GerES V (2014-2017). PAH metabolites were analysed in urine samples of 516 participants and could be quantified in 88-100% of the samples. Geometric mean concentrations were: 0.785 µg/L (0.688 µg/gcreatinine) for 1-OH-naphthalene, 4.233 µg/L (3.706 µg/gcrea) for 2-OH-naphthalene, 0.139 µg/L (0.122 µg/gcrea) for 1-OH-phenanthrene, 0.085 µg/L (0.075 µg/gcrea) for 2-OH-phenanthrene, 0.131 µg/L (0.115 µg/gcrea) for 3-OH-phenanthrene, 0.045 µg/L (0.040 µg/gcrea) for 4-OH-phenanthrene, 0.058 µg/L (0.050 µg/gcrea) for 9-OH-phenanthrene, 0.511 µg/L (0.448 µg/gcrea) for Σ-OH-phenanthrene, and 0.099 µg/L (0.087 µg/gcrea) for 1-OH-pyrene. Analyses of subgroups revealed higher PAH metabolite concentrations in young children compared to adolescents, and also in residents of former East Germany compared to those living in former West Germany. Increased urinary PAH metabolite concentrations were found in participants using domestic fuel for heating or gas for cooking. Plastic objects were identified as another potential source of exposure. Urinary concentrations of naphthalene and fluorene metabolites were elevated in active smokers and to the same extent in non-smokers exposed to passive smoking. Comparison with previous cycles of GerES revealed a decrease over time and a further decline in the still significant differences in urinary PAH metabolite concentrations of participants living in former East versus West Germany.

Phthalate metabolites in urine of children and adolescents in Germany. Human biomonitoring results of the German Environmental Survey GerES V, 2014-2017.

During the population representative German Environmental Survey of Children and Adolescents (GerES V, 2014-2017) 2256 first-morning void urine samples from 3 to 17 years old children and adolescents were analysed for 21 metabolites of 11 different phthalates (di-methyl phthalate (DMP), di-ethyl phthalate (DEP), butylbenzyl phthalate (BBzP), di-iso-butyl phthalate (DiBP), di-n-butyl phthalate (DnBP), di-cyclohexyl phthalate (DCHP), di-n-pentyl phthalate (DnPeP), di-(2-ethylhexyl) phthalate (DEHP), di-iso-nonyl phthalate (DiNP), di-iso-decyl phthalate (DiDP) and di-n-octyl phthalate (DnOP)). Metabolites of DMP, DEP, BBzP, DiBP, DnBP, DEHP, DiNP and DiDP were found in 97%-100% of the participants, DCHP and DnPeP in 6%, and DnOP in none of the urine samples. Geometric means (GM) were highest for metabolites of DiBP (MiBP: 26.1 µg/L), DEP (MEP: 25.8 µg/L), DnBP (MnBP: 20.9 µg/L), and DEHP (cx-MEPP: 11.9 µg/L). For all phthalates but DEP, GMs were consistently higher in the 3-5 years old children than in the 14-17 years old adolescents. For DEHP, the age differences were most pronounced. All detectable phthalate biomarker concentrations were positively associated with the levels of the respective phthalate in house dust. In GerES V we found considerably lower phthalate biomarker levels than in the preceding GerES IV (2003-2006). GMs of biomarker levels in GerES V were only 18% (BBzP), 23% (MnBP), 23% (DEHP), 29% (MiBP) and 57% (DiNP) of those measured a decade earlier in GerES IV. However, some children and adolescents still exceeded health-based guidance values in the current GerES V. 0.38% of the participants had levels of DnBP, 0.08% levels of DEHP and 0.007% levels of DiNP which were higher than the respective health-based guidance values. Accordingly, for these persons an impact on health cannot be excluded with sufficient certainty. The ongoing and substantial exposure of vulnerable children and adolescents to many phthalates confirms the need of a continued monitoring of established phthalates, whether regulated or not, as well as of potential substitutes. With this biomonitoring approach we provide a picture of current individual and cumulative exposure developments and body burdens to phthalates, thus providing support for timely and effective chemicals policies and legislation.

Hexamoll® DINCH and DPHP metabolites in urine of children and adolescents in Germany. Human biomonitoring results of the German Environmental Survey GerES V, 2014-2017.

The production and use of the plasticisers Hexamoll® DINCH (di-(iso-nonyl)-cyclohexane-1,2-dicarboxylate) and DPHP (di-(2-propylheptyl) phthalate) have increased after both chemicals were introduced into the market in the early 2000s as substitutes for restricted high molecular weight phthalates. During the population representative German Environmental Survey (GerES) of Children and Adolescents (GerES V, 2014-2017), we collected urine samples and measured the concentrations of DINCH and DPHP metabolites in 2228 and in a subsample of 516 participants, respectively. We detected DINCH and DPHP metabolites in 100% and 62% of the 3-17 years old children and adolescents, respectively. Geometric means of DINCH metabolites were 2.27 µg/L for OH-MINCH, 0.93 µg/L for oxo-MINCH, 1.14 µg/L for cx-MINCH and 3.47 µg/L for DINCH (Σ of OH-MINCH + cx-MINCH). Geometric means of DPHP metabolites were 0.30 µg/L for OH-MPHP, 0.32 µg/L for oxo-MPHP and 0.64 µg/L for DPHP (Σ of OH-MPHP + oxo-MPHP). The 3-5 years old children had almost 3-fold higher DINCH biomarkers levels than adolescents (14-17 years). Higher concentrations of DPHP biomarkers among young children only became apparent after creatinine adjustment. Urinary levels of DINCH but not of DPHP biomarkers were associated with the levels of the respective plasticisers in house dust. When compared to HBM health-based guidance values, we observed no exceedance of the HBM-I value of 1 mg/L for DPHP (Σ of OH-MPHP + oxo-MPHP). However, 0.04% of the children exceeded the health based guidance value HBM-I of 3 mg/L for DINCH (Σ of OH-MINCH + cx-MINCH). This finding shows that even a less toxic replacement of restricted chemicals can reach exposures in some individuals, at which, according to current knowledge, health impacts cannot be excluded with sufficient certainty. In conclusion, we provide representative data on DINCH and DPHP exposure of children and adolescents in Germany. Further surveillance is warranted to assess the substitution process of plasticisers, and to advise exposure reduction measures, especially for highly exposed children and adolescents. Providing the results to the European HBM Initiative HBM4EU will support risk assessment and risk management not only in Germany but also in Europe.

Human biomonitoring reference values: Differences and similarities between approaches for identifying unusually high exposure of pollutants in humans.

In exposure and risk assessment, the indication of unusually high exposure levels in humans to chemicals has been considered as an important objective for decades. To realize this objective, reference values (RV) need to be derived. However, while there is a tendency towards using the 95th percentile as a basis for deriving these reference values there is still no consensus. Moreover, side approaches have evolved including deriving RVs based on other percentiles, reporting multiple RVs or only reporting percentiles. The purpose of this article is to give an overview of the current literature, to point out differences and similarities between existing approaches, and to highlight important criteria for the derivation of RVs. We observe the majority of studies to base RVs on the 95th percentile and its 95% confidence interval which can been justified by statistical paradigms, present arguments for a single defined reference value, and discuss characteristics which call for more consistency. To conclude, our overview provides a first step towards a more homogenous and standardized derivation procedure to identify unusually high exposures in exposure science.