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Glycol ethers are a class of semi-volatile substances used as solvents in a variety of consumer products like cleaning agents, paints, cosmetics as well as chemical intermediates. We determined 11 metabolites of ethylene and propylene glycol ethers in 44 urine samples of German residents (background level study) and in urine samples of individuals after exposure to glycol ethers during cleaning activities (exposure study). In the study on the background exposure, methoxyacetic acid and phenoxyacetic acid (PhAA) could be detected in each urine sample with median (95th percentile) values of 0.11 mgL(-1) (0.30 mgL(-1)) and 0.80 mgL(-1) (23.6 mgL(-1)), respectively. The other metabolites were found in a limited number of samples or in none. In the exposure study, 5-8 rooms were cleaned with a cleaner containing ethylene glycol monobutyl ether (EGBE), propylene glycol monobutyl ether (PGBE), or ethylene glycol monopropyl ether (EGPE). During cleaning the mean levels in the indoor air were 7.5 mgm(-3) (EGBE), 3.0 mgm(-3) (PGBE), and 3.3 mgm(-3) (EGPE), respectively. The related metabolite levels analysed in the urine of the residents of the rooms at the day of cleaning were 2.4 mgL(-1) for butoxyacetic acid, 0.06 mgL(-1) for 2-butoxypropionic acid, and 2.3 mgL(-1) for n-propoxyacetic acid. Overall, our study indicates that the exposure of the population to glycol ethers is generally low, with the exception of PhAA. Moreover, the results of the cleaning scenarios demonstrate that the use of indoor cleaning agents containing glycol ethers can lead to a detectable internal exposure of residents., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Polybrominated diphenyl ethers (PBDE) are used as flame retardants in a wide variety of products. As part of the Integrated Exposure Assessment Survey (INES), this study aimed to characterize the exposure of an adult German population using duplicate diet samples, which were collected daily over seven consecutive days, and indoor air and house dust measurements. Our study population consisted of 27 female and 23 male healthy subjects, aged 14-60 years, all of whom resided in 34 homes in southern Bavaria. In these 34 residences the air was sampled using glass fiber filters and polyurethane foams and the dust was collected from used vacuum cleaner bags. The median (95th percentile) daily dietary intake of six Tetra- to HeptaBDE congeners was 1.2 ng/kg b.w. (3.3 ng/kg b.w.) or 67.8 ng/day (208 ng/day) (calculated from the 7-day median values of each study subject). Concentrations in indoor air and dust (cumulative Tri- to DecaBDE congener readings) ranged from 8.2 to 477 pg/m(3) (median: 37.8 pg/m(3)) and 36.6 to 1580 ng/g (median: 386 ng/g), respectively. For some congeners, we identified a significant correlation between air and dust levels. The median (95th percentile) blood concentration of total Tetra- to HexaBDE congener readings was 5.6 (13.2)ng/g lipid. No significant sex differences were observed, but higher blood concentrations were found in younger participants. Using a simplified toxicokinetic model to predict the body burden from exposure doses led to results that were of the same order of magnitude as the measured blood concentrations. Based on these measurements and given our exposure assumptions, we estimated for the total tetra- to heptabrominated congener count an average (high) comprehensive total daily intake of 1.2 ng/kg b.w. (2.5 ng/kg b.w.). Overall, our results suggest that dietary exposure is the dominant intake pathway at least in our study population, responsible for 97% (average intake) and 95% (high intake) of the total intake of an adult population.

Polychlorinated biphenyls (PCB) were widely used in numerous industrial and commercial applications in high quantities in the past. Based on their persistence in the environment, their tendency to accumulate in the organism and their specific health effects, PCBs have to be assessed as critical substances. Because the dietary intake was assumed to be the main intake route, the Integrated Exposure Assessment Survey (INES) aimed to measure the recent exposure to PCBs in Germany. The study consisted of 10 female and 10 male participants living in Munich and surroundings. The participants collected dietary duplicates of all food consumed and prepared as for consumption over 7 consecutive days. Altogether the 6 non-dioxin-like PCB congeners 28, 52, 101, 138, 153 and 180 ndl-PCB or, respectively, indicator PCB and furthermore the congener 118 were detected using a gas chromatographic method. Dietary intake was calculated using the amount of food eaten daily and the results from the duplicates. Using the sum of PCB 138, 153 and 180 multiplied by 4, the daily intake ranged from 4.0 to 24.1 ng/kg b.w. (median: 9.5 ng/kg b.w.). On the contrary, the daily intake was 2.9 to 20.6 ng/kg b.w. (median: 11.2 ng/kg b.w.) if the sum of the 6 indicator PCBs multiplied by factor 2 was used for quantification. No sex-related difference of the dietary intake was observable. Overall, it can be concluded that the dietary PCB intake has further decreased in the last years in Germany. At present, the toxicological database is not suitable to assess the risks coming solely from the non-dioxin-like PCBs because it is not possible to differentiate between non dioxin-like and dioxin-like effects in toxicological studies. Nevertheless, a further reduction of PCB exposure via food by searching for possible sources is needed.

Objectives: Perfluorinated compounds (PFCs) are a large group of chemicals produced for several decades and widely used for many industrial and consumer applications. Because of their global occurrence in different environmental media, their persistence, and their potential to bioaccumulate in organisms they are of toxicological and public concern., Methods: In the present study, the internal exposure to perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in 356 human plasma samples collected from an adult population in Germany in 2005 is quantified., Results: We were able to detect the target analytes in all plasma samples and observed a significant correlation between the PFOS and PFOA concentrations. In female participants, the levels of PFOS and PFOA ranged between 2.5-30.7 (median: 10.9 microg/l) and 1.5-16.2 microg/l (median: 4.8 microg/l), respectively. In males we observed concentrations from 2.1 to 55.0 microg/l (median: 13.7 microg/l) for PFOS and from 0.5 to 19.1 microg/l (median: 5.7 microg/l) for PFOA. A significant correlation between both PFOS and PFOA concentrations and gender was observed. We also found increased levels of the PFCs with increasing age of the participants, but this association reached statistical significance among females only., Conclusions: Our data agree well with results of other recent studies in Europe and suggest that the current exposure of the adult German population is lower than the exposure of the US and Canadian population. The sources of human exposure are currently not well understood. Toxicological implications are restricted to animal studies and occupational investigations not adequate for quantitative risk assessment in humans. Overall, more scientific research is necessary to characterize the body burden of PFCs (especially for relevant subsets of the population) and the main sources and routes, which are responsible for human exposure and possible health implications of these compounds.