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Background: An association between N-acetyltransferase 2 (NAT2) slow acetylation and bladder cancer has been consistently observed in epidemiologic studies. However, evidence has been mainly derived from case–control studies and was sparse from cohort studies. We evaluated the association between NAT2 slow acetylation and bladder cancer in a case–control study nested in the European Prospective Investigation into Cancer and Nutrition.Methods: Exposure to aromatic amines and polycyclic aromatic hydrocarbons (PAH) could be assessed for 754 cases and 833 controls for whom occupational information was documented. A semiquantitative job-exposure matrix was applied to at-risk occupations to estimate the exposure as low, medium, or high based on tertiles of the distribution of the exposure score in controls. Using a comprehensive genotyping, NAT2 acetylation status could be categorized from 6-single-nucleotide polymorphism genotypes as slow or fast in 607 cases and 695 controls with DNA from archived blood samples.Results: Occupational exposure to aromatic amines and PAH was associated with an increased bladder cancer risk [upper tertile of the distribution of the exposure score: OR = 1.37; 95% confidence interval (CI), 1.02–1.84, and OR = 1.50; 95% CI, 1.09–2.05, respectively]. NAT2 slow acetylation did not modify these risk estimates and was not itself associated with bladder cancer risk (OR = 1.02; 95% CI, 0.81–1.29).Conclusions: These findings confirm established or suspected occupational risk factors but not the anticipated role of NAT2 slow acetylation in bladder cancer. No interaction was detected between NAT2 and any exposure of interest, including smoking.Impact: Genetic testing for NAT2 would be inappropriate in occupational settings. Cancer Epidemiol Biomarkers Prev; 22(11); 2055–65. ©2013 AACR.

PDF - 80KB, Association of smoking and occupational exposure with bladder cancer by NAT2 acetylation in cases and controls from EPIC.

PDF - 63KB, NAT2 variants and bladder cancer risk for 607 cases and 695 controls nested in EPIC.

PDF - 73KB, Joint effects of NAT2 acetylation status and occupational exposure to aromatic amines on the risk of bladder cancer (492 cases and 569 controls).

PDF - 84KB, Association of working in at-risk occupations with bladder cancer in men (609 cases and 665 controls) and women (145 cases and 168 controls) from EPIC.

PDF - 84KB, Joint effects of smoking and occupational exposure to aromatic amines and polycyclic aromatic hydrocarbons on the risk of bladder cancer (754 cases and 833 controls).

In Germany strong efforts have been made within the last years to develop new methods for human biomonitoring (HBM). The German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB) and the German Chemical Industry Association e. V. (VCI) cooperate since 2010 to increase the knowledge on the internal exposure of the general population to chemicals. The projects aim is to promote human biomonitoring by developing new analytical methods Key partner of the cooperation is the German Environment Agency (UBA) which has been entrusted with the scientific coordination. Another key partner is the “HBM Expert Panel” which each year puts together a list of chemicals of interest to the project from which the Steering Committee of the project choses up to five substances for which method development will be started. Emphasis is placed on substances with either a potential health relevance or on substances to which the general population is potentially exposed to a considerable extent. The HBM Expert Panel also advises on method development. Once a method is developed, it is usually first applied to about 40 non-occupationally exposed individuals. A next step is applying the methods to different samples. Either, if the time trend is of major interest, to samples from the German Environmental Specimen Bank, or, in case exposure sources and distribution of exposure levels in the general population are the focus, the new methods are applied to samples from children and adolescents from the population representative 5th German Environmental Survey (GerES V). Results are expected in late 2018. This article describes the challenges faced during method development and solutions found. An overview presents the 34 selected substances, the 14 methods developed and the 7 HBM-I values derived in the period from 2010 to mid 2016.

The German Human Biomonitoring Commission (HBM Commission) derives health-related guidance values (Human Biomonitoring assessment values, HBM values) according to the procedures described in the HBM Commission’s position papers. Since the last adaption of the methodology in 2014, the HBM Commission has established a series of new HBM values, mainly on the basis of internationally agreed TDI/RfD values, or of toxicologically well- founded points of departure observed in animal studies. The derivation of these new HBM values for HBCDD, triclosan, 2-MBT, PFOA and PFOS as well as for the metabolites of glycol ethers, of Hexamoll® DINCH®, DPHP, DEHTP, NMP, NEP, and 4-MBC is specified, and the HBM values are presented together with already established HBM values for other substances. Furthermore, the HBM Commission has defined provisional reference values for 2-methoxyacetic acid and for several parabens in the urine of the German population. It has also updated provisional reference values for PCB in the blood of the German population. An overview of all available reference values is given.

Background: Phthalates, bisphenol A (BPA) and triclosan (TCS) are detectable in the vast majority of people. Most humans are continuously exposed to these chemicals due to their presence in food or in everyday consumer products. The measurement of these compounds in family members may help to explore the impact of major lifestyle factors on exposure. Mothers and (young) children are especially interesting to study, as they mostly share considerable parts of daily life together. Materials and methods: Phthalate metabolites, bisphenol A (BPA) and triclosan (TCS) were measured in first morning void urine, collected in mother-child pairs (n = 129) on the same day. The mothers (27-45y) and their children (6-11y) were recruited in the Brussels agglomeration and rural areas of Belgium in the context of the European COPHES-DEMOCOPHES human biomonitoring project. Face-to-face questionnaires gathered information on major exposure sources and lifestyle factors. Exposure determinants were assessed by multiple linear regression analysis. Results: The investigated compounds were detectable in nearly all mothers (92.8–100%) and all children (95.2–100%). The range (P90 vs. P10) of differences in urinary concentrations within each age group was for most compounds around 10–20 fold, and was very high for TCS up to 35 and 350-fold in children and mothers respectively. Some participants exceeded the tolerable daily intake guidelines as far as they were available from the European Food Safety Authority (EFSA). Overall, for BPA, the urinary concentrations were similar among both age groups. Most urinary phthalate metabolites were higher in children compared to the mothers, except for monoethyl phthalate (MEP). TCS levels were generally higher in the mothers. Despite the difference in mothers' and children's urinary concentrations, the creatinine-corrected levels were correlated for all biomarkers (Spearman rank r = 0.32 to 0.66, p < 0.001). Furthermore, for phthalates, similar home and lifestyle factors were associated with the urinary concentrations in both age groups: home renovation during last two years or redecoration during the last year for di-ethyl phthalate (DEP); PVC in home for di-n-butyl phthalate (DnBP), di-iso-butyl phthalate (DiBP) and butyl benzyl phthalate (BBzP), and personal care products use for DiBP and DnBP. Based on questionnaire information on general food type consumption patterns, the exposure variability could not be explained. However, comparing the phthalate intake from the current study with earlier assessed Belgian food intake calculations for both ages, food in general was estimated to be the major intake source for di-ethyl hexyl phthalate (DEHP), with diminishing importance for BBzP, DiBP and DnBP. Conclusion: Our results confirm, that children and their mothers, sharing diets and home environments, also share exposure in common consumer products related chemicals. By collecting morning urine levels on the same day, and using basic questionnaires, suspected exposure routes could be unraveled.

Auf der Grundidee des Siegerentwurfs zum Schinkel-Wettbewerb 2009 entstand zur Bundesgartenschau 2015 in der Havelregion eine 350 Meter lange, im Grundriss S-foermig geschwungene Fussgaengerbruecke, welche die Schwedendamminsel mit dem Weinberg ueber die Havel und das Gewaesser Hellers Loch ansteigend verbindet. Die staehlerne Bruecke besteht aus einem Durchlauftraeger ueber 15 Felder mit Stuetzweiten zwischen 9 und 60 Metern sowie zwei asymmetrischen Bogenbruecken von 50 beziehungsweise 60 Metern Laenge. Die Unterbauten sind ueber Grossbohrpfaehle und Pfahlkopfplatten im tragfaehigen Sand gegruendet. Durch die monolithische Verbindung der Stahltragwerke mit den Widerlagern entstand ein integrales Bauwerk ohne Lager und Uebergangskonstruktionen. Die Pfeiler sind dazu ebenfalls biegesteif mit dem Stuetzenfuss und dem Ueberbau verbunden. Beide Bogenbruecken aus mit Beton gefuellten Stahlhohlkaesten weisen im Grundriss eine sehr starke Kruemmung auf. Die Versteifungstraeger sind ueber Haenger mit den Boegen verbunden. Zur Verbesserung des Verhaltens gegen fussgaengerinduzierte Schwingungen erhielt die Konstruktion eine 15 Zentimeter dicke Gehwegplatte. Im Grundriss weiten sich die Bereiche vor den Bruecken halbkreisfoermig auf und bieten Verweilbereiche mit Baenken und weitem Blick in die Havellandschaft. Aufgrund der schlanken Bauweise ist das Tragwerk sehr anfaellig gegen Biege- und Torsionsschwingungen. Dies fuehrte zur Anordnung von Schwingungstilgern in den beiden Bogenbruecken. Die Werkstattplanung mit circa 3.500 verschiedenen schiefwinkligen Blechzuschnitten war wegen des um alle Achsen gekruemmten Verlaufs der Bruecke sehr aufwendig. Aufgrund des engen Terminplans erfolgte die Werkstattfertigung zeitgleich in vier verschiedenen Fertigungsstaetten. Die Montage der Bruecke mit Mobilkraenen war gekennzeichnet durch beengte Platzverhaeltnisse inmitten des vorhandenen Baumbestands entlang der Havel und ihren Zufluessen. Im Anschluss an die Montage der Stahlkonstruktion wurde die Gehwegplatte betoniert. Die Bruecke konnte rechtzeitig zum Beginn der Bundesgartenschau fertiggestellt werden. ABSTRACT IN ENGLISH: In Rathenow, a new 350 m long bicycling and footbridge spans the river Havel. The ogee Weinberg-Bridge was the main highlight of the Federal Garden Show 2015 in the Havelland. The horticultural show was located in the cities of Brandenburg/Havel, Premnitz, Rathenow and Rhinow/Stoelln of the region of Brandenburg as well as in the city of Havelberg in Saxony-Anhalt. Spanning over the two waters (Havel and Hellers Loch), the construction consists of two arch bridges with slanted archs, an unilaterally jointed bridge deck, which enlarges until the middle of the arch and offers benches for a stay on the bridge. The unilateral connection of the ropes enables unimpeded views over the waters and the trees in the surrounding area of the bridge. The permanent connection between the scenery of the Schwedendamm and the Weinberg is the most important part of the touristic development process of the city and the Optikpark. (A)

Parabens are widely used as antimicrobial preservatives in personal care and consumer products, food and pharmaceuticals. Due to their ubiquity, humans are constantly exposed to these chemicals. We assessed exposure to nine parabens (methyl-, ethyl-, n- and iso-propyl-, n- and iso-butyl-, benzyl-, pentyl- and heptyl paraben) in the German population from 1995 to 2012 based on 660 24h urine samples from the German Environmental Specimen Bank (ESB) using on-line HPLC coupled to isotope dilution tandem mass spectrometry. The limit of quantification (LOQ) was 0.5 μg/L for all parabens. We detected methyl-, ethyl- and n-propyl paraben in 79-99% of samples, followed by n-butyl paraben in 40% of samples. We infrequently detected iso-butyl-, iso-propyl- and benzyl paraben in 24%, 4% and 1.4% of samples, respectively. Urinary concentrations were highest for methyl paraben (median 39.8 μg/L; 95th percentile 319 μg/L) followed by n-propyl paraben (4.8 μg/L; 95th percentile 74.0 μg/L) and ethyl paraben (2.1 μg/L; 95th percentile 39.1 μg/L). Women had significantly higher urinary levels for all parabens than men, except for benzyl paraben. Samples from the ESB revealed that over the investigation period of nearly 20 years urinary paraben levels remained surprisingly constant; only methyl paraben had a significant increase, for both men and women. We found strong correlations between methyl- and n-propyl paraben and between n- and iso-butyl paraben. These results indicate that parabens are used in combination and arise from common sources of exposure. Urinary excretion factors are needed to extrapolate from individual urinary concentrations to actual doses.

Human biomonitoring (HBM) is an effective tool to assess human exposure to environmental pollutants, but comparable HBM data in Europe are lacking. In order to expedite harmonization of HBM studies on a European scale, the twin projects COPHES (Consortium to Perform Human Biomonitoring on a European Scale) and DEMOCOPHES (Demonstration of a study to Coordinate and Perform Human Biomonitoring on a European Scale) were formed, comprising 35 partners from 27 European countries. In COPHES a research scheme and guidelines were developed to exemplarily measure in a pilot study mercury in hair, cadmium, cotinine and several phthalate metabolites in urine of 6-11year old children and their mothers in an urban and a rural region. Seventeen European countries simultaneously conducted this cross-sectional DEMOCOPHES feasibility study. The German study population was taken in the city of Bochum and in the Higher Sauerland District, comprising 120 mother-child pairs. In the present paper features of the study implementation are presented. German exposure concentrations of the pollutants are reported and compared with European average concentrations from DEMOCOPHES and with those measured in the representative German Environmental Survey (GerES IV). German DEMOCOPHES concentrations for mercury and cotinine were lower than the European average. However, 47% of the children were still exposed to environmental tobacco smoke (ETS) outside their home, which gives further potential for enhancing protection of children from ETS. Compared with samples from the other European countries German participating children had lower concentrations of the phthalate metabolites MEP and of the sum of 3 DEHP-metabolites (MEHP, 5OH-MEHP and 5oxo-MEHP), about the same concentrations of the phthalate metabolites MBzP and MiBP and higher concentrations of the phthalate metabolite MnBP. 2.5% of the German children had concentrations of the sum of 4 DEHP-metabolites and 4.2% had concentrations of MnBP that exceeded health based guidance values, indicating reasons for concern. Continuous HBM is necessary to track changes of pollutant exposure over time. Therefore Germany will continue to cooperate on the harmonisation of European human biomonitoring to support the chemicals regulation with the best possible exposure data to protect Europe's people against environmental health risks. publisher: Elsevier articletitle: Human biomonitoring pilot study DEMOCOPHES in Germany: Contribution to a harmonized European approach journaltitle: International Journal of Hygiene and Environmental Health articlelink: http://dx.doi.org/10.1016/j.ijheh.2017.01.012 content_type: article copyright: © 2017 The Authors. Published by Elsevier GmbH. ispartof: International Journal of Hygiene and Environmental Health vol:220 issue:4 pages:686-696 ispartof: location:Germany status: published

Background: Phthalates are chemicals which are widespread in the environment. Although the impacts on health of such exposure are unclear, there is evidence of a possible impact on the incidence of a diverse range of diseases. Monitoring of human exposure to phthalates is therefore important. This study aimed to determine the extent of phthalate exposure among mothers and their children in both rural and urban areas in Ireland, and to identify factors associated with elevated concentrations. It formed part of the 'Demonstration of a study to Co-ordinate and Perform Human Biomonitoring on a European Scale' (DEMOCOPHES) pilot biomonitoring study. Methods: the concentration of phthalate metabolites were determined from a convenience sample of 120 mother/child pairs. The median age of the children was 8 years. A questionnaire was used to collect information regarding lifestyle and environmental conditions of the children and mothers. Rigorous quality assurance within DEMOCOPHES guaranteed the accuracy and international comparability of results. Results: Phthalate metabolites were detected in all of the samples from both children and mothers. Concentrations were significantly higher in respondents from families with lower educational attainment and in those exposed to such items as polyvinyl chloride (PVC), fast food and personal care products (PCP). Conclusions: The study demonstrates that human biomonitoring for assessing exposure to phthalates can be undertaken in Ireland and that the exposure of the population is widespread. Further work will be necessary before the consequences of this exposure are understood. We would like to acknowledge the funders of the DEMOCOPHES project (LIFE09 ENV/BE/000410) which was jointly financed by the European Commission Programme LIFE and each participating country (http://www.eu-hbm.info/democophes/project-partners). In addition, we would like to thank the COPHES project for providing the operational and scientific framework (European Community’s Seventh Framework Programme—DG Research Grant Agreement Number 244237). Special thanks to all the mothers and children who agreed to participate in the study. In addition the WP team leaders and the national implementation teams, particularly the Irish national team (Catherine Cosgrove, David O’Brien, Rita O’Grady, Niamh McGrath, Anita Larini, Carol Nolan, Gemma McGrane and Sarah Duffy) for support in terms of data collection, analysis, and interpretation. We would like to thank Claire Dunne and Fiona Kavanagh for proof reading and assistance throughout the project, and Padraig Manning, Clinical Librarian and Elaine Scanlon, Library assistant from the HSE library in Steevens’ hospital, Dublin 8 for their assistance in accessing the literature. Sí

We developed a fast, selective and sensitive on-line LC/LC-MS/MS method for the simultaneous determination of nine parabens and seven environmental phenols in urine. Parabens are widely used as antimicrobial preservatives. Bisphenol A, triclosan, triclocarban, 2-phenylphenol, and benzophenones are used inter alia in disinfectants, sunscreens and in polymers. Some of these substances are suspected endocrine disruptors. Limits of quantification and analytical quality criteria fully met the needs for determining exposure levels occurring in the general population. We analyzed 157 spot urine samples from the general German population (59 females, 39 males and 59 children). For the parabens, we found methyl, ethyl and n-propyl paraben with high detection rates (77-98%), followed by n-butyl (36%), iso-butyl (17%), iso-propyl (3%) and benzyl paraben (3%). We detected no pentyl and heptyl paraben. Urinary concentrations were highest for methyl paraben (median 24.5 μg/L; 95th percentile 379 μg/L) followed by ethyl (1.4 μg/L; 35.2 μg/L) and n-propyl paraben (1.2 μg/L; 68.1 μg/L). Other environmental phenols with high detection rates were BPA (95%), triclosan (45%) and benzophenone 1 and 3 (26%). For most of the parabens/environmental phenols we found higher urinary levels in females than in males or children, probably due to differences in (personal care) product use. However, high levels (in the mg/L range) were also observed in children. Exposure to the above substances is occurring worldwide. Differences between countries do seem to exist and might be caused by different product compositions or different use habits. Human metabolism data is urgently needed to extrapolate from urinary biomarker levels to doses actually taken up.

BACKGROUND: Monitoring of human exposure to mercury is important due to its adverse health effects. This study aimed to determine the extent of mercury exposure among mothers and their children in Ireland, and to identify factors associated with elevated levels. It formed part of the Demonstration of a study to Coordinate and Perform Human Biomonitoring on a European Scale (DEMOCOPHES) pilot biomonitoring study. METHODS: Hair mercury concentrations were determined from a convenience sample of 120 mother/child pairs. Mothers also completed a questionnaire. Rigorous quality assurance within DEMOCOPHES guaranteed the accuracy and international comparability of results. RESULTS: Mercury was detected in 79.2% of the samples from mothers, and 62.5% of children's samples. Arithmetic mean levels in mothers (0.262 µg/g hair) and children (0.149 µg /g hair) did not exceed the US EPA guidance value. Levels were significantly higher for those with higher education, and those who consumed more fish. CONCLUSIONS: The study demonstrates the benefit of human biomonitoring for assessing and comparing internal exposure levels, both on a population and an individual basis. It enables the potential harmful impact of mercury to be minimised in those highly exposed, and can therefore significantly contribute to population health. We would like to acknowledge the funders of the DEMOCOPHES project (LIFE09 ENV/BE/000410) which was jointly financed by the European Commission Programme LIFE and each participating country (http://www.eu-hbm.info/democophes/project-partners). In addition, we would like to thank the COPHES project for providing the operational and scientific framework (European Community’s Seventh Framework Programme—DG Research Grant Agreement Number 244237). Sí

© 2013 Elsevier GmbH. All rights reserved., The objective of COPHES (Consortium to Perform Human biomonitoring on a European Scale) was to develop a harmonised approach to conduct human biomonitoring on a Europeanscale. COPHES developed a systematic approach for designing and conducting a pilot study for an EU-wide cross-sectional human biomonitoring (HBM) study and for the implementation of the fieldwork procedures. The approach gave the basis for discussion of the main aspects of study design and conduct, and provided a decision making tool which can be applied to many other studies. Each decision that had to be taken was listed in a table of options with their advantages and disadvantages. Based on this the rationale of the decisions could be explained and be transparent. This was important because an EU-wide HBM study demands openness of all decisions taken to encourage as many countries as possible to participate and accept the initiative undertaken. Based on this approach the following study design was suggested: a cross-sectional study including 120 children aged 6–11 years and their mothers aged up to 45 years from each participating country. For the pilot study the children should be sampled in equal shares in an urban and a rural location. Only healthy children and mothers (no metabolic disturbances) should be included, who have a sufficient knowledge of the local language and have been living at least for 5 years at the sampling location. Occupational exposure should not be an exclusion criterion. Recruitment should be performed via inhabitant registries or schools as an alternative option. Measures suitable to increase the response rate should be applied. Preferably, the families should be visited at home and interviewed face-to-face. Various quality control measures to guarantee a good fieldwork performance were recommended., European Commission, DG for Researchand Innovation (RTD), who funded COPHES in the 7th Framework Programme (DG Research – No. 244237) and DG Environment,who co-funded DEMOCOPHES under the LIFE+ Programme (DG Environment-Life09 ENV/BE000410) together with the participating countries.

A harmonized human biomonitoring pilot study was set up within the frame of the European projects DEMOCOPHES and COPHES. In 17 European countries, biomarkers of some environmental pollutants, including urinary cadmium and hair mercury, were measured in children and their mothers in order to obtain European-wide comparison values on these chemicals. The Belgian participant population consisted in 129 school children (6–11 years) and their mothers (≤ 45 years) living in urban or rural areas of Belgium. The geometric mean levels for mercury in hair were 0.383 μg/g and 0.204 μg/g for respectively mothers and children. Cadmium in mother's and children's urine was detected at a geometric mean concentration of respectively 0.21 and 0.04 μg/l. For both biomarkers, levels measured in the mothers and their child were correlated. While the urinary cadmium levels increased with age, no trend was found for hair mercury content, except the fact that mothers hold higher levels than children. The hair mercury content increased significantly with the number of dental amalgam fillings, explaining partially the higher levels in the mothers by their higher presence rate of these amalgams compared to children. Fish or seafood consumption was the other main parameter determining the mercury levels in hair. No relationship was found between smoking status and cadmium or mercury levels, but the studied population included very few smokers. Urinary cadmium levels were higher in both mothers and children living in urban areas, while for mercury this difference was only significant for children. Our small population showed urinary cadmium and hair mercury levels lower than the health based guidelines suggested by the WHO or the JECFA (Joint FAO/WHO Expert Committee on Food Additives). Only 1% had cadmium level slightly higher than the German HBM-I value (1 μg/l for adults), and 9% exceeded the 1 μg mercury/g hair suggested by the US EPA.

This article has no abstract Keywords: propylene glycol 1-methyl ether; 1-methoxypropanol-2; propylene glycol monomethyl ether; occupational exposure; biological tolerance value; BAT value; toxicity

Cobalt The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re-evaluated the exposure equivalents for carcinogenic substances (EKA) for cobalt and cobalt compounds in 2006. Available publications are described in detail. Cobalt is potentially carcinogenic and mutagenic and has a sensitizing effect. This metal has an effect on the bronchopulmonary system, the heart and blood. Most of the recent studies on occupational exposure to cobalt contained data on concentrations in air and urine, only in some cases also in blood. As the concentration of cobalt in urine is about 10 times higher than that in blood, the detection of cobalt in urine both diagnostically and analytically is more reliable and the method is not invasive, the EKA between cobalt in air and cobalt in blood is withdrawn. The relationships between the concentration of cobalt in air and that in urine derived from the more recent studies show results that agree with comparable relationships derived in 1989. The Commission therefore retains the correlation already derived in 1986 between the concentration of cobalt in ambient air and that in urine, and extends this to include lower concentrations. The correlation contains air concentrations from 0.01 to 0.5 mg cobalt/m3 and concentrations of cobalt in urine from 6 to 300 µg/L. The sampling time is at the end of the exposure or shift, for long-term exposures after several shifts. Keywords: cobalt; cobalt(II)sulfide; cobalt(II)oxide; cobalt(ll,lll)oxide; cobalt(ll)carbonate; cobalt(ll)sulfate (heptahydrate); occupational exposure; biological tolerance value; BAT value; EKA; toxicity

The analytical method describes the specific determination of 3‐methyl‐5‐isopropylhydantoin (MIH), a hemoglobin adduct of N,N‐dimethylformamide. Following addition of 13C5,15N‐3‐methyl‐5‐isopropylhydantoin (13C5,15N‐MIH) as internal standard, isolated globin is subjected to acid hydrolysis for one hour at 110°C. After pH adjustment (pH 3 – 5) the hydrolysate is extracted twice with ethyl acetate. The combined extracts are washed with sodium hydrogen carbonate solution and dried under a stream of nitrogen. The residue is dissolved in ethyl acetate. An aliquot of the solution is analyzed using GC–MS. For calibration purposes, calibration standards are prepared in pooled globin. They are processed in the same way as the samples to be analyzed.

We previously reported DNA strand break frequencies and adduct levels of 8-oxo-7,8-dihydro-20-deoxyguanosine (8-oxo-dGuo) in 171 blood samples of coke oven, refractory, graphite electrode, and converter workers exposed to polycyclic aromatic hydrocarbons (PAH). Construction workers (n = 48) were used as controls (Marczynski et al. 2009). Internal dose was assessed by the determination of 1-hydroxypyrene (1-OHP) and the sum of five hydroxyphenanthrenes ( P OHPhe) in post-shift urine samples. Our results clearly indicated increased DNA damage in exposed workers on a group level. The results of the dose–response associations on the individual level, however, did not reveal quantitative correlations between measured exposures and effects. We have discussed several potential reasons for the observed results. In brief, internal exposure and effect was based on single time points (post-shift samples), and kinetics for the formation of 8-oxo-dGuo and DNA strand breaks after exposure to chemical carcinogens such as PAH are not known in detail in humans. The individual exposure circumstances such as varying routes of exposures (dermal vs. inhalation) and potential co-exposures to dust or other chemical compounds at the workplace may have contributed to the dose–response association rather than exposure to PAH alone (Courter et al. 2007). Although PAH can undergo redox cycling and are capable of inducing oxidative DNA damage (Park et al. 2008), DNA strand breaks and 8-oxo-dGuo in blood are general biomarkers of oxidative stress, thus being pathwayspecific rather than substance-specific. Finally, PAH are a complex mixture consisting of carcinogenic and non-carcinogenic compounds and exist in varying profiles in different industries and the environment (Rehwagen et al. 2005; Unwin et al. 2006). 1-OHP and P OHPhe are metabolites of pyrene and phenanthrene, thus representing noncarcinogenic PAH rather than carcinogenic PAH. In order to narrow down the reasons for the lacking association between exposures to PAH and DNA damage on the individual level, we re-analyzed the role of carcinogenic PAH. For this purpose, we focused on benzo[a]pyrene (B[a]P) and naphthalene. B[a]P is a complete carcinogen and often used as a positive control in bioassays when studying genotoxicity and carcinogenicity of chemical compounds (IARC 2010). In addition, B[a]P has been shown to have the highest enzyme inducing efficiency in the lung and liver of rodents, thus self-enhancing the formation of reactive electrophilic and carcinogenic intermediates during its metabolism (Elovaara et al. 2007; Skupinska et al. 2007). Naphthalene has been shown to be carcinogenic in rodents at high concentrations after inhalation (NTP 2000). Available biomarkers to assess H. U. Kafferlein (&) B. Marczynski J. Angerer H.-P. Rihs B. Pesch T. Bruning Institut fur Pravention und Arbeitsmedizin der Deutschen Gesetzlichen Unfallversicherung, Institut der Ruhr Universitat Bochum (IPA), Burkle-de-la-Camp Platz 1, 44789 Bochum, Germany e-mail: kaefferlein@ipa-dguv.de

Human exposure to Bisphenol A (BPA) is omnipresent. Both the extent of the exposure and its toxicological relevance are controversially discussed. We aim to reliably determine and evaluate the extent of BPA body burden in the German population from 1995 to 2009 based on 600 24 h urine samples and corresponding plasma samples from the Environmental Specimen Bank. We determined total and unconjugated BPA in urine and plasma using on-line solid-phase extraction high-performance liquid chromatography coupled to isotope dilution tandem mass spectrometry with a limit of quantification (LOQ) of 0.1 μg/l. In the stored urines, total BPA was quantifiable in >96% (median: 1.49 μg/l; 95th percentile: 7.37 μg/l), whereas unconjugated BPA was quantifiable only in

Di(isononyl)cyclohexane-1,2-dicarboxylate (DINCH) is a major substitute for some high molecular weight phthalates that adversely affect reproductive function. Like for the phthalates a broad exposure of the population has to be expected. We postulated the DINCH monoester (MINCH) and secondary oxidized metabolites (OH-MINCH, cx-MINCH and oxo-MINCH) as human metabolites and possible biomarkers of DINCH exposure. We developed an on-line HPLC–MS/MS method for their determination in human urine. Identification was performed with authentic standard substances and quantification via isotope dilution. The analytical method is highly selective and sensitive with limits of quantification (LOQ) between 0.05 μg/l and 0.1 μg/l. In a pilot study with 22 volunteers from the general German population oxidized DINCH metabolites were found in above 80% of the samples. OH-MINCH was most abundant (mean 0.71 μg/l; maximum 3.69 μg/l) followed by cx-MINCH (0.61 μg/l; 2.82 μg/l) and oxo-MINCH (0.33 μg/l; 1.05 μg/l). All three oxidized metabolites correlated strongly among each other ( ρ ≥ 0.76). MINCH was detected in one sample only and has to be regarded a weak marker of exposure. With this analytical method we are able to perform human metabolism studies to provide metabolic conversion factors and to investigate the extent of DINCH exposure in the general population.

The general population is exposed to acrylamide (AA) mainly through food and tobacco smoke. AA is classified as probably carcinogenic to humans. Glycidamide (GA), as the primary oxidative metabolite, was identified to be the ultimate genotoxic agent. This warrants full investigation of the oxidative pathway in AA metabolism and the share of the oxidative compared to the reductive pathway. 2,3-Dihydroxy-propionamide (OH-PA) as the direct hydrolysis product of GA has been shown to be a major urinary oxidative metabolite in human AA metabolism. We developed an analytical method to reliably quantify OH-PA in urine by GC-MS after a multistep procedure including "stripping" on a solid phase material, lyophilization, silylation and re-extraction. With a detection limit of 1 μg/L, our method is sensitive enough to quantify OH-PA in all urine samples of the general population. Within and between series precisions were between 1.9% and 8.2% and mean recoveries between 97% and 101%. We applied this method to 30 urine samples from the general population. In all the samples, OH-PA was present in concentrations between 6.8 and 109.4 μg/L (median, 49.7 μg/L) with no difference between smokers and non-smokers. OH-PA concentrations were approximately ten times higher than expected from the metabolism of AA via GA. Currently, we cannot confirm OH-PA to be a specific biomarker of the oxidative pathway of AA metabolism. Other sources than AA respectively GA might need to be considered for the formation of OH-PA.

We determined the internal exposure of 111 German primary school starters by analyzing urinary metabolites of six phthalates: butyl benzyl phthalate (BBzP), di-iso-butyl phthalate (DiBP), di-n-butyl phthalate (DnBP), di (2-ethylhexyl) phthalate (DEHP), di-iso-nonyl phthalate (DiNP) and di-iso-decylphthalate (DiDP). From the urinary metabolite levels, we calculated daily intakes and related these values to Tolerable Daily Intake (TDI) values. By introducing the concept of a relative cumulative Tolerable Daily Intake (TDI(cum)) value, we tried to account for the cumulative exposure to several of the above-mentioned phthalates. The TDI(cum) was derived as follows: the daily intake (DI) calculated from the metabolite level was divided by the TDI for each phthalate; this ratio was multiplied by 100% indicating the TDI percentage for which the DI accounted. Finally the % TDIs of the different phthalates were totalled to get the TDI(cum). A TDI(cum) above 100% is a potential cause for concern. We confirmed the ubiquitous exposure of the children to all phthalates investigated. Exposures were within range of levels previously reported for GerES, albeit slightly lower. Regarding daily intakes, two children exceeded the TDI for DnBP, whereas one child closely approached the TDI for DEHP. 24% of the children exceeded the TDI(cum) for the three most critical phthalates: DEHP, DnBP and DiBP. Furthermore, 54% of the children had total exposures that used up more than 50% the TDI(cum). Therefore, the overall exposure to a number of phthalates, and the knowledge that these phthalates (and other anti-androgens) act in a dose-additive manner, urgently warrants a cumulative risk assessment approach.

To study the associations between exposure to vapours and aerosols of bitumen and genotoxic effects, a cross-sectional and cross-shift study was conducted in 320 exposed workers and 118 non-exposed construction workers. Ambient air measurements were carried out to assess external exposure to vapours and aerosols of bitumen. Hydroxylated metabolites of naphthalene, phenanthrene and pyrene were measured in urine, whereas (+)-anti-benzo[a]pyrene-7,8-diol-9,10-epoxide ((+)-anti-BPDE), 8-oxo-7,8-dihydro-2'-deoxyguanosine (8oxodGuo) and DNA strand breaks were determined in blood. Significantly higher levels of 8-oxodGuo adducts and DNA strand breaks were found in both pre- and post-shift blood samples of exposed workers compared to those of the referents. No differences between exposed workers and referents were observed for (+)-anti-BPDE. Moreover, no positive associations between DNA damage and magnitude of airborne exposure to vapours and aerosols of bitumen could be observed in our study. Additionally, no relevant association between the urinary metabolites of PAH and the DNA damage in blood was observed. Overall, our results indicate increased oxidative DNA damage in workers exposed to vapours and aerosols of bitumen compared to non-exposed referents at the group level. However, increased DNA strand breaks in bitumen workers were still within the range of those found in non-exposed and healthy persons as reported earlier. Due to the lack of an association between oxidative DNA damage and exposure levels at the workplaces under study, the observed increase in genotoxic effects in bitumen workers cannot be attributed to vapours and aerosols of bitumen.

The chemical complexity of emissions from bitumen applications is a challenge in the assessment of exposure. Personal sampling of vapours and aerosols of bitumen was organized in 320 bitumen-exposed workers and 69 non-exposed construction workers during 2001-2008. Area sampling was conducted at 44 construction sites. Area and personal sampling of vapours and aerosols of bitumen showed similar concentrations between 5 and 10 mg/m(3), while area sampling yielded higher concentrations above the former occupational exposure limit (OEL) of 10 mg/m(3). The median concentration of personal bitumen exposure was 3.46 mg/m(3) (inter-quartile range 1.80-5.90 mg/m(3)). Only few workers were exposed above the former OEL. The specificity of the method measuring C-H stretch vibration is limited. This accounts for a median background level of 0.20 mg/m³ in non-exposed workers which is likely due to ubiquitous aliphatic hydrocarbons. Further, area measurements of polycyclic aromatic hydrocarbons (PAHs) were taken at 25 construction sites. U.S. EPA PAHs were determined with GC/MS, with the result of a median concentration of 2.47 μg/m(3) at 15 mastic asphalt worksites associated with vapours and aerosols of bitumen, with a Spearman correlation coefficient of 0.45 (95% CI -0.13 to 0.78). PAH exposure at mastic-asphalt works was higher than at reference worksites (median 0.21 μg/m(3)), but about one order of magnitude lower compared to coke-oven works. For a comparison of concentrations of vapours and aerosols of bitumen and PAHs in asphalt works, differences in sampling and analytical methods must to be taken into account.

Phthalate exposure was found to be associated with endocrine disruption, respiratory effects, reproductive and developmental toxicity. The intensive use of plastics may be increasing the exposure to phthalates in Taiwanese population, particularly for young children. We studied phthalate metabolites in pregnant women and their newborns in a prospective cohort from a medical center in Central Taiwan. One hundred maternal urine samples and 30 paired cord blood and milk samples were randomly selected from all of participants (430 pregnant women). Eleven phthalate metabolites (MEHP, 5OH-MEHP, 2cx-MEHP, 5cx-MEPP, 5oxo-MEHP, MiBP, MnBP, MBzP, OH-MiNP, oxo-MiNP, and cx-MiNP) representing the exposure to five commonly used phthalates (DEHP, di-isobutyl phthalate (DiBP), DnBP, BBP, DiNP) were measured in urine of pregnant women, cord serum and breast milk after delivery, and in urine of their children. Exposure was estimated with excretion factors and correlation among metabolites of the same parent compound. Thirty and 59 urinary samples from 2 and 5 years-old children were randomly selected from 185 children successfully followed. Total urinary phthalate metabolite concentration (geometric mean, μg L⁻¹) was found to be higher in 2-years-olds (398.6) and 5-years-olds (333.7) than pregnant women (205.2). Metabolites in urine are mainly from DEHP. The proportion of DiNP metabolites was higher in children urine (4.39 and 8.31%, ages 2 and 5) than in adults (0.83%) (p0.01). Compared to urinary levels, phthalate metabolite levels are low in cord blood (37.45) and milk (14.90). DEHP metabolite levels in women's urine and their corresponding cord blood are significantly correlated. Compared to other populations in the world, DEHP derived metabolites in maternal urine were higher, while phthalate metabolite levels in milk and cord blood were similar. The level of phthalate metabolites in milk and cord blood were comparable to those found in other populations. Further studies of health effects related to DEHP and DiNP exposure are necessary for the children.

Some phthalates are developmental and reproductive toxicants in animals. Exposure to phthalates is considered to be potentially harmful to human health as well. Based on a comprehensive literature research, we present an overview of the sources of human phthalate exposure and results of exposure assessments with special focus on human biomonitoring data. Among the general population, there is widespread exposure to a number of phthalates. Foodstuff is the major source of phthalate exposure, particularly for the long-chain phthalates such as di(2-ethylhexyl) phthalate. For short-chain phthalates such as di-n-butyl-phthalate, additional pathways are of relevance. In general, children are exposed to higher phthalate doses than adults. Especially, high exposures can occur through some medications or medical devices. By comparing exposure data with existing limit values, one can also assess the risks associated with exposure to phthalates. Within the general population, some individuals exceed tolerable daily intake values for one or more phthalates. In high exposure groups, (intensive medical care, medications) tolerable daily intake transgressions can be substantial. Recent findings from animal studies suggest that a cumulative risk assessment for phthalates is warranted, and a cumulative exposure assessment to phthalates via human biomonitoring is a major step into this direction.

A dose of 0.99 mg d(3)-acrylamide (d(3)-AA) (13.2 μg/kg body weight) was ingested by a healthy male volunteer. Urine samples were collected over a period of 46 h after the intake and analyzed for the hydrolysis product of glycidamide (GA), 2,3-dihydroxy-propionamide (OH-PA), a metabolite of the toxicologically relevant oxidative AA metabolism pathway; 5.4% of the administered d(3)-AA dose was eliminated as OH-PA within 46 h after ingestion. Therefore, OH-PA represents a major metabolite of the oxidative metabolism pathway. Elimination kinetics of OH-PA is similar to the oxidative metabolites N-acetyl-S-(2-carbamoyl-2-hydroxyethyl)-cysteine (GAMA) and N-acetyl-S-(1-carbamoyl-2-hydroxyethyl)-cysteine (iso-GAMA). The major excretion of d(3)-OH-PA took place between 8 and 22 h with the highest urinary d(3)-OH-PA concentration (c (max)) of 69.3 μg/L urine, 18 h (t (max)) postdose. OH-PA (5.4%), together with the other known urinary metabolites of the oxidative pathway GAMA (4.6%) and iso-GAMA (0.8%), represents 10.8% of the total AA dose. The share of the oxidative pathway metabolites is much smaller than the share of the reductive pathway metabolite N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA) that represents 51.7% of the ingested d(3)-AA dose. However, this new quantitative human data on OH-PA together with the previous data on the other oxidative pathway metabolites are of special importance when evaluating the carcinogenic potential of AA and when comparing human data with data from animal studies.

In Germany, the Human Biomonitoring Commission of the Federal Environment Agency continuously assesses environmental pollutants to derive human biomonitoring (HBM) and reference values. HBM values are derived on the basis of toxicological, epidemiological studies or toxicokinetic extrapolation which provides a concentration of a substance or its metabolites corresponding to tolerable intake doses. Two levels are defined: HBM I and HBM II. In 1996, the Commission set a HBM I of 100 microg/l for lead in blood of children < or =12 years and females of a reproductive age and a HBM I of 150 microg/l for the other persons. In the light of findings from epidemiological studies on effects below 100 microg/l, the Commission reevaluated and confirmed the assessment from 1996 in 2002. Meanwhile the general decline in lead pollution has allowed recent studies to include more cohorts with blood lead levels predominantly below 100 microg/l. These data confirm that lead's critical effect, particularly on the developing organism and during early childhood, concerns the nervous system and that negative correlations between blood lead levels and relevant variables (cognitive function, behaviour) occur at blood lead levels below 100 microg/l. The new data also support the possible persistence of lead-induced effects into adulthood. It is not possible to indicate thresholds. Concerning the estimation of the size of the effects, recent studies suggest that lead's influence on development is comparable with other factors influencing development. Furthermore inorganic lead and compounds were classified by IARC in group 2A (probably carcinogenic to humans) and by the German Research Foundation (MAK Commission) in category 2 (to be regarded as human carcinogen). We conclude that any setting of an "effect threshold" for blood lead levels would be arbitrary and therefore unjustified. As a consequence the Commission suspends the HBM values for lead in blood of children and adults.

Phthalates are suspected to act as endocrine modulators in humans and exert reproductive toxicity. The general population is exposed to phthalates through nutrition, consumer products, medications and medical devices. The aim of the present study is to explore whether internal phthalate exposure represented by metabolites of di(2-ethylhexyl) phthalate (DEHP) can be related to human markers of reproductive function (i.e. semen concentration, motility and morphology).We recruited 349 men who were part of subfertile couples and were referred for fertility work-up between April 2004 and November 2005. Semen analysis was performed according to recommendations of the World Health Organization (WHO). Parameters were dichotomized based on 1999 WHO reference values for sperm concentration (20million/ml) and motility (50% sperm with progressive motility), as well as Tygerberg strict criteria for morphology (4% normal forms). We analyzed internal DEHP exposure in single spot urine samples by determining its secondary metabolites mono(2-ethyl-5-oxo-hexyl)phthalate (5oxo-MEHP), mono(2-ethyl-5-hydroxyhexyl)phthalate (5OH-MEHP) and 5carboxy-mono(2-ethylhexyl)phthalate (5cx-MEPP) next to the monoester metabolite mono(2-ethylhexyl)phthalate (MEHP). Logistic regression was performed for the three semen parameters (concentration, motility, and normal morphology) to estimate their dependence on the sum of the four DEHP metabolites (DEHP-4) under consideration. Adjustment was performed for age, duration of abstinence, and smoking status.DEHP metabolites of n=349 men (age: median=34ys) were analysed. Median concentrations [microg/l] were MEHP (n=337) 4.35, 5OH-MEHP (n=341) 12.66, 5oxo-MEHP (n=341) 9.02, and 5cx- MEPP (n=292) 14.53. Semen parameters of n=349 men were analysed by logistic regression. Semen concentration (20mio/ml: 35%) or sperm motility (WHO A+B50%=20%) were not found to be associated statistically significantly with the sum the DEHP metabolites (DEHP-4).Metabolites of DEHP and other phthalates analyzed in urine are very specific for determining recent internal phthalate exposure. According to our evaluation human reproductive parameters from semen analyses do not show significant associations with concentrations of DEHP metabolites determined in spot urine sampled at the day of andrological examination.

Trialkyl esters of phosphoric acid are widely used as flame retardants. The corresponding dialkylphosphates are formed as the main metabolites in animal experiments. We extended a previously published method for the determination of four organophosphorus flame retardant metabolites [bis(2-chloroethyl) phosphate, diphenyl phosphate, di-m-cresyl phosphate and di-p-cresyl phosphate] to be able to determine di-n-butyl phosphate (DBP) and bis(2-chloropropyl) phosphate (BCPP) in human urine samples additionally in one run. After solid-phase extraction, derivatization with pentafluorobenzyl bromide and further solid-phase cleanup, the extracts were analysed by gas chromatography-tandem mass spectrometry. The limits of detection were 0.25 microg/l for both analytes. Interday imprecisions were 2-6%. To show the applicability of the method, the internal burden of 25 persons of the population was determined. Twelve percent of the urine samples analysed tested positive for BCPP at concentrations from below the limit of detection to 0.85 microg/l; one sample contained 0.26 microg/l DBP.

In Arnsberg, Sauerland area Germany, 40000 residents were exposed to PFOA-contaminated drinking water (500-640ng PFOA/l; May 2006). In July 2006, the PFOA-concentrations in drinking water were lowered significantly by activated charcoal filtering in the waterworks, mostly below the limit of detection (10ng/l). A first human biomonitoring study performed in autumn 2006 revealed that PFOA-concentrations in blood plasma of residents living in Arnsberg were 4.5-8.3 times higher than in the reference groups. One year after the first survey, all participants (2006: 164 mothers, 90 children, 101 men) were invited to take part in a follow-up study. It was the aim of the study to determine the decline of the PFOA-concentrations in blood plasma. 288 persons (81%) were included in the statistical analysis. The (geometric) mean PFOA-concentrations in blood plasma of Arnsberg's residents decreased from 22.1 to 17.4 microg/l in children, from 23.4 to 18.8 microg/l in mothers and from 25.3 to 23.4 microg/l in men within one year. The average (geometric mean) changes in each individual's PFOA-concentrations were approximately 10 (men), 17 (mothers) and 20 (children) percent/year. The observed decline in PFOA-concentrations indicates a slow elimination in humans. This finding in groups of the general population is in agreement with data on long elimination half-lives observed in occupationally exposed workers.

The present population-based cross-sectional study in 1008 volunteers was aimed at quantifying the internal burden of acrylamide (AM) in the general population using hemoglobin adduct levels as biomarker of exposure. Based on these adduct levels the risk of (AM) related hazardous health effects in the general population is assessed. Hemoglobin adducts of acrylamide were detected in 999 out of 1008 analyzed blood samples (99.1%). Smoking can be regarded as a main source of overall acrylamide intake in persons without occupational exposure to acrylamide but a second main influence factor, i.e. food intake, is of environmental importance. Due to the sizable study population the 95th percentile differentiated in smokers and non-smokers are actually the best available reference values for an internal environmental acrylamide burden. Based on our data neurotoxicity and reproductive toxicity due to acrylamide are not likely to occur in the general population except very high consumers. However, carcinogenicity and mutagenicity are possible hazardous health effects for the general population.

Exposure to polycyclic aromatic hydrocarbons (PAH) and DNA damage were analyzed in coke oven (n = 37), refractory (n = 96), graphite electrode (n = 26), and converter workers (n = 12), whereas construction workers (n = 48) served as referents. PAH exposure was assessed by personal air sampling during shift and biological monitoring in urine post shift (1-hydroxypyrene, 1-OHP and 1-, 2 + 9-, 3-, 4-hydroxyphenanthrenes, SigmaOHPHE). DNA damage was measured by 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) and DNA strand breaks in blood post shift. Median 1-OHP and SigmaOHPHE were highest in converter workers (13.5 and 37.2 microg/g crea). The industrial setting contributed to the metabolite concentrations rather than the air-borne concentration alone. Other routes of uptake, probably dermal, influenced associations between air-borne concentrations and levels of PAH metabolites in urine making biomonitoring results preferred parameters to assess exposure to PAH. DNA damage in terms of 8-oxo-dGuo and DNA strand breaks was higher in exposed workers compared to referents ranking highest for graphite-electrode production. The type of industry contributed to genotoxic DNA damage and DNA damage was not unequivocally associated to PAH on the individual level most likely due to potential contributions of co-exposures.

Acrylamide (AA), a substance classified as probably carcinogenic to humans, was detected for the first time in food products in 2002. AA can be primarily found in foods containing carbohydrates and proteins, where it is formed during the heating process. Exposure assessment based on food consumption data revealed an average daily intake of AA between 0.3 and 0.8 μg/kg BW/day. These data have been confirmed by human biomonitoring using haemoglobin adducts of AA in blood or the specific mercapturic acids in urine. However, human biomonitoring data on the internal exposure of children were only sporadically available. Especially data about the excretion of both relevant mercapturic acids were missing. The mercapturic acids other than the haemoglobin adducts give the recent AA exposure of the last 24 h. In this study, we quantify the internal exposure of AA and the genotoxic metabolite glycidamide (GA) in 110 children with regard to their exposure through diet and/or environmental tobacco smoke. Material and methods Hundred and ten 5–6-year-old children were randomly selected. Their dietary habits as well as their exposure to the environmental tobacco smoke were assessed by means of a questionnaire. By means of spot urine samples, mercapturic acids of acrylamide (AAMA) and mercapturic acids of glycidamide (GAMA) were analysed with LC-ESI-MS/MS. Results Median (95th percentile) urinary levels were 36.0 (152.7) μg AAMA/l and 13.4 (55.9) μg GAMA/l. Based on the metabolite levels, the median uptake of acrylamide was calculated to be 0.54 μg/kg BW/d. A number of associations with the consumption of French fries, various potato products, as well as fried cereals could be found. Significant results were found for French fries. No correlations between the exposure to environmental smoke and cotinine levels in urine were found. Conclusion This is the first study to show the presence of AAMA and GAMA in urine specimens of 110 children, thus providing evidence for a background exposure by nutrition. Median (95th percentile) uptake of AA in children was 0.54 (1.91) μg/kg bodyweight and day, exceeding exposure in adults by 50%. These findings support the efforts to minimize AA formation and contamination in food. Comparing our findings with that of other human studies, there are hints that children have a higher AA intake than adults and that children more effectively oxidize AA. Both findings indicate that children might be the most vulnerable group of the population.

Background: Phthalates, reproductive toxicants in animals, are synthetic chemicals with ubiquitous human exposures because of their extensive use, with potential detrimental health effects. Infants are considered to represent a population at increased risk, as they are exposed early in life to several different sources of exposure to phthalates. Objectives and methods: Little information exists on phthalate exposure through breast milk from different geographic areas. By means of a LC/LC–MS/MS method we tested the presence of several different phthalate metabolites in breast milk from 62 healthy mothers living in Southern Italy. Results: The simple monoesters mono-isobutyl phthalate (MiBP) (median 18.8 μg/l) and mono(2-ethylhexyl) phthalate (MEHP) (median 8.4 μg/l) were present in all milk samples, whereas mono-n-butyl phthalate (MnBP) (median 1.5 μg/l) and mono-benzyl phthalate (MBzP) (median

Organophosphorus flame retardants (OPFR), phosphorus triesters, are widely used chemicals with a high share of the worldwide flame retardant market. In animal experiments, dialkyl- and diarylphosphates are the main metabolites of OPFR. Therefore we elaborated a GC-MS/MS-method for the detection of OPFR-metabolites in human urine after solid phase extraction and derivatization with pentafluorobenzylbromide. The limits of detection range from 0.1 to 1 microg/l. Interday imprecision were 2-8%. The applicability of the method is shown by determination of the internal burden of 30 persons of the German general population. OPFR-metabolite concentrations range from

A simple pharmacokinetic model to predict concentrations of metabolites of di-2-ethylhexyl phthalate, DEHP, in humans starting from intakes of DEHP was developed and applied. This model predicts serum and urine concentrations of five DEHP metabolites: MEHP, 5oxo-MEHP, 5OH-MEHP, 5cx-MEPP, and 2cx-MMHP. The model was calibrated using data from an individual who dosed himself with 48.5 mg DEHP, and then took blood and urine samples over a 44-h period. The calibrated model was then used in two applications: one on a second set of individuals whose exposure to DEHP was through PVC medical devices in a blood platelet donation procedure, and one on background exposures in the United States (US). Based on 2001/02 NHANES data, median US background urine concentrations of MEHP, 5OH-MEHP, and 5oxo-MEHP are 4.1, 20.1, and 14.0 microg/l, respectively. Creatine and urine volume-correction approaches were used to backcalculate an average daily dose of DEHP in the range of 0.6-2.2 microg/kg per day. A "background cohort" including 8 individuals and 57 complete days of urination were assumed to be exposed to1.5 microg/kg per day, spread out in equal doses of 0.3 microg/kg per day at 0900, 1200, 1500, 1800, and 2100 h. The average predicted urine concentrations were 4.6, 15.9, and 9.4 microg/l for MEHP, 5OH-MEHP, and 5oxo-MEHP. These are similar, but the two secondary metabolites are slightly lower than medians found in NHANES. This slight difference between the NHANES results and the background simulations could have been due to differences in metabolism between the individual who provided the calibration data (61-year-old Caucasian male) and the general US population. Another explanation evaluated was that urine concentrations further from the time of exposure may have larger disparities between MEHP and the two secondary metabolites as compared with concentrations measured closer to the time of exposure.

Concerns about reproductive and developmental health risks of exposure to organophosphate (OP) pesticides, phthalates, and bisphenol A (BPA) among the general population are increasing. Six dialkyl phosphate (DAP) metabolites, 3,5,6-trichloro-2-pyridinol (TCPy), BPA, and fourteen phthalate metabolites were measured in 10 pooled urine samples representing 110 pregnant women who participated in the Norwegian Mother and Child Birth Cohort (MoBa) study in 2004. Daily intakes were estimated from urinary data and compared with reference doses (RfDs) and daily tolerable intakes (TDIs). The MoBa women had a higher mean BPA concentration (4.50 mu g/L) than the pregnant women in the Generation R Study (Generation R) in the Netherlands and the National Health and Nutrition Examination Survey (NHANES) in the United States. The mean concentration of total DAP metabolites (24.20 mu g/L) in MoBa women was higher than that in NHANES women but lower than that in Generation R women. The diethyl phthalate metabolite mono-ethyl phthalate (MEP) was the dominant phthalate metabolite in all three studies, with the mean concentrations of greater than 300 mu g/L. The MoBa and Generation R women had higher mean concentrations of mono-n-butyl phthalate (MnBP) and mono-isobutyl phthalate (MiBP) than the NHANES women. The estimated average daily intakes of BPA, chlorpyrifos/chlorpyrifos-methyl and phthalates in MoBa (and the other two studies) were below the RfDs and TDIs. The higher levels of metabolites in the MoBa participants may have been from intake via pesticide residues in food (organophosphates), consumption of canned food, especially fish/seafood (BPA), and use of personal care products (selected phthalates). Published by Elsevier GmbH.

Background: Trace element external quality assessment schemes monitor laboratory performance and provide a stimulus for improvement in accuracy. However, monitoring of participant performance varies according to the scheme and can lead to conflicting conclusions. Methods: Quality specifications based on biological intra- and interindividual variability were calculated and compared to those currently used by various trace element external quality assessment schemes for plasma or serum copper, zinc, and selenium concentrations. For this purpose, we evaluated results reported by participating laboratories in different schemes, at key concentrations, using z scores. Results: Minimal quality specifications developed from the biological intra- and interindividual variability were, for Cu, ±0.84 μmol/L or 12% of the assigned target concentration, whichever is greater; for Zn, ±1.20 μmol/L or 15% of the assigned target concentration, whichever is greater; and for Se, ±0.072 μmol/L or 12% of the assigned target concentration, whichever is greater. Reported performance of the participating laboratories depended on analyte, concentration, and the selected quality specification. In addition, the most commonly used methods for the determination of Cu, Zn, and Se may give different results. Conclusions: The proposed minimal quality specifications based on biological variation are generally slightly less stringent than those currently in use, although they do not drastically change the performance evaluation in the different schemes. These specifications are a first step in the harmonization of practices among the schemes and remain to be evaluated.

Syntheses of the labelled oxidative metabolites of acrylamide and acrylonitrile – reference compounds for the evaluation of human exposure to important toxicants – are reported. For that, L-cystine tert-butyl ester was acetylated and the product reductively cleaved to L-cysteine tert-butyl ester, which reacted with carbamoyl[D3]oxirane (obtained from [D3]acrylonitrile and 30 % aq. H2O2 at pH = 7.0–7.5) and afforded a separable mixture of tert-butyl N-acetyl-S-(2-hydroxy-2-carbamoyl[D3]ethyl)cysteinate and tert-butyl N-acetyl-S-(1-carbamoyl-2-hydroxy[D3]ethyl)cysteinate (ca. 9:1). Removal of the tert-butyl group in these intermediates with aq. HCl gave the final deuterated internal standards with carbamoyl residues. Protection of the secondary hydroxy group in the major intermediate with tBuMe2SiCl/imidazole in DMF followed by dehydration of the carbamoyl group (trifluoroacetic anhydride/pyridine in CH2Cl2) and stepwise removal of the tert-butyl and tBuMe2Si protecting groups (TFA, Et3SiH,CH2Cl2; aq. HF in MeCN) yielded N-acetyl-S-(2-cyano-2-hydroxy[D3]ethyl)cysteine. Monoprotection of [D4]ethylene glycol with tBuMe2SiCl and NaH in THF, oxidation to tBuMe2SiOCD2CDO, conversion to tBuMe2SiOCD2CD(OH)CN and tBuMe2SiOCD2CD(OTs)CN followed by nucleophilic substitution of the tosyloxy group with N-acetyl-L-cysteine (MeOD, Et3N) and deprotection with 4 M HCl in dioxane resulted in N-acetyl-S-(1-cyano-2-hydroxy[D3]ethyl)cysteine. All transformations (except the last but one) gave the respective products in good yields.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Polycyclic aromatic hydrocarbons (PAH) are metabolized in a complex manner. Although biological activity is associated with diol-epoxide formation, phenolic metabolites have predominantly been used in human biomonitoring. In this study monohydroxylated and new metabolites were characterized as biomarkers for occupational PAH exposure. In 97 male workers, personal exposure to 16 airborne PAH compounds was measured during shift. In postshift urine, 1-hydroxypyrene and 1,6- and 1,8-dihydroxypyrene (1-OHP, DiOHP) were determined as metabolites of pyrene (P), and the sum of 1-, 2-, 3-, 4-, and 9-hydroxyphenanthrenes (OHPHE), and PHE-dihydrodiols (PHED) as metabolites of phenanthrene (PHE). The referent group comprised 21 nonsmoking construction workers. Median (interquartile range) shift concentrations of airborne P and PHE were 1.46 (0.62-4.05 microg/m(3)) and 10.9 (3.69-23.77 microg/m(3)), respectively. The corresponding parameters were 3.86 (2.08-7.44) microg/g creatinine (crn) for 1-OHP, 0.66 (0.17-1.65) microg/g crn for DiOHP, 11.44 (5.21-34.76) microg/g crn for OHPHE, and 12.28 (3.3-97.76) microg/g crn for PHED in PAH-exposed workers. The median levels of 1-OHP and OHPHE were 0.09 (0.08-0.17 microg/m(3)) and 0.59 (0.45-1.39 microg/m(3)), respectively, in the referents. PHE correlated significantly with OHPHE and PHED, and P with 1-OHP but not with DiOHP. Under a doubling of PHE, OHPHE increased by a factor of 1.56 and PHED by 1.57. With a doubling of P, 1-OHP rose by 1.31 and DiOHP by 1.27. P is predominantly metabolized into 1-OHP, whereas PHE is metabolized equally into OHPHE and PHED. Thus metabolites of PHE were found as reliable biomarkers for PAH exposure.

In our research project entitled "Chemical irritative and/or genotoxic effect of fumes of bitumen under high processing temperatures on the airways," 73 mastic asphalt workers exposed to fumes of bitumen and 49 construction nonexposed workers were analyzed and compared with respect to polycyclic aromatic hydrocarbons (PAHs) exposure and exposure-related health effects. In order to assess the internal exposure the monohydroxylated metabolites of pyrene, 1- hydroxypyrene (1-OHP), and phenanthrene, 1-, 2- and 9-, and 3- and 4-hydroxyphenanthrene (OHPH) were determined in pre- and post-shift urinary samples. Significantly higher concentrations 1-OHP and OHPH were detected in the post-shift urine samples of 7 mastic asphalt workers working on the same construction site compared to the reference workers and all other 66 mastic asphalt workers. The adjusted mean OHPH in the reference, 66 mastic worker, and 7 worker subgroups was 1022, 1544, and 12919 ng/g creatinine (crn) respectively, indicating a marked rise in the 7 worker subgroup. In addition, there was a more than 12-fold increase of PAH metabolites from pre- to post-shift in these 7 workers, whereas in the other mastic asphalt workers there was only a twofold rise in PAH-metabolite concentration between pre- and post-shift values. The analysis of a drilling core from the construction site of the seven workers led to the detection of the source for this marked PAH exposure during the working shift as being coal tar plates, which were, without knowledge of the workers and coordinators, the underground material of the mastic asphalt layer. The evaluation of the stationary workplace concentration showed enhanced levels of phenanthrene, pyrene, fluorene, anthracene, and acenaphthene during working shifts at the construction site of these seven workers. Our study shows that biological monitoring is also a useful tool for the detection of unrecognized sources with high PAH concentrations.

Summary In human metabolism studies we found that after oral application of di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DiNP) and di(2-propylheptyl) phthalate (DPHP), at least 74, 44 and 34%, respectively, are excreted via urine. In contrast to the short chain phthalates, their oxidized products, not the simple monoesters, were found to be the main metabolites. Based on urinary phthalate metabolite concentrations we estimated in 102 German subjects between 6 and 80 years of age median daily intakes (μg/kg/day) of 2.7 for DEHP, 2.1 for di-n-butyl phthalate, 1.5 for diisobutyl phthalate, 0.6 for DiNP, and 0.3 for butylbenzyl phthalate. In general, children have higher exposures compared to adults and seem to have a more effective oxidative metabolism of phthalates. For individual phthalates tolerable daily intake (TDI) values have been deduced. However, in rats some phthalates have been shown to act as endocrine disrupters via a common mechanism of action in a dose-additive manner. Therefore, the concept of a cumulative TDI value may be more appropriate for the consideration of the overall exposure and the potential human health risks resulting from everyday and simultaneous exposure to several phthalates.

Aniline (ANI) and the human carcinogen o-toluidine (OT) are released at the workplace during the production and processing of rubber. Recently, we showed in rubber industry workers that a frequent use of skin barrier creams (SBC) increased the internal exposure of ANI and OT. In the present study, diffusion cells were used to investigate the effects of two SBC and one skin care cream (SCC) on percutaneous penetration of neat ANI and OT as well as of OT from a mixture with a workplace specific lubricant. The experiments were carried out with untreated and with skin creams treated human skin. A considerable percutaneous penetration enhancement of test compounds was observed for treated skin compared with untreated skin; the highest enhancement (mean factors 6.2-12.3) was found for SBC (based on oil in water emulsion) treated skin. The lowest penetration enhancement showed SCC treated skin (mean factors 4.2-9.7). The in vitro data support our findings in workers that the percutaneous absorption of aromatic amines significantly increases in presence of skin creams. The efficacy of skin creams to protect the percutaneous penetration of aromatic amines is not confirmed by our own experiments.

This study was conducted to assess external and internal exposure of workers to polycyclic aromatic hydrocarbons (PAHs). In this context, the analytical and diagnostical reliability of 3-hydroxybenzo[a]pyrene (3OH-BaP) as a biomarker of internal exposure to PAHs was established.Ambient and biological monitoring was carried out of 225 PAH-exposed employees of different industries. External exposure was determined by personal air sampling and analysis of 16 EPA-PAH. Internal exposure was examined by the urinary metabolites 3OH-BaP, 1-hydroxypyrene (OH-Pyr) and monohydroxylated phenanthrenes (OH-Phens).Benzo[a]pyrene (BaP) was detected at all workplaces. Concentrations in the breathing zone of the workers ranged from below the limit of detection up to 44.3 mug/m(3). In biological monitoring, urinary 3OH-BaP was found in median concentrations of 0.8 ng/g creatinine (crea) and the 95th percentile of 6.7 ng/g crea. The results ranged from the limit of detection up to 19.5 ng/g crea. Only 1% of the analysed samples showed concentrations below the limit of detection (0.05 ng/l). Regarding median concentrations, workers in coking plants showed lower 3OH-BaP concentrations (0.5 ng/g crea) than those employed in the production of fireproof material in refractories (1.1 ng/g crea), converter infeed (1.2 ng/g crea) and graphite electrode production (1.3 ng/g crea). Strong correlations of 3OH-BaP with OH-Pyr and the sum of OH-Phens were found for the workplaces converter infeed, coking plants and graphite electrode production (r(Pearson) ranging from 0.618 to 0.867, p0.001). The poor correlation of BaP in the air and 3OH-BaP in urine is most probably caused by routes of uptake other than via air-for example, dermal uptake.3OH-BaP as a metabolite of the carcinogenic BaP could be shown to be a diagnostically specific and sensitive biomarker for determining the internal exposure of workers in different industries. Using this method, the estimation of health risks for workers can be fundamentally improved, because the 3OH-BaP represents the group of carcinogenic PAHs. The procedure for analysing 3OH-BaP is complex, but it is robust and produces reliable results.