ADONA and perfluoroalkylated substances in plasma samples of German blood donors living in South Germany

Perfluorinated compounds are fully fluorinated anthropogenic substances that have been used in various products, applications, and industrial processes. Due to their persistence and toxic effects, some of them are restricted, and therefore replacement products have been developed. The aim of the study was to quantify the body burden of different perfluorinated substances in two adult populations living close to or about 80km apart from a former perfluorooctanoate (PFOA) production plant who are exposed via drinking water, and in a control population. In this plant, the replacement emulsifier 3H-perfluoro-3-[(3-methoxy-propoxy)propanoic acid] (ADONA) has been used in the production of fluoropolymers since 2008. We quantified 7 perfluorinated compounds and ADONA in a total of 396 plasma samples collected at different time points. With regard to samples collected in 2015 or 2016, the highest 95th percentile levels were 13.5μg/l for perfluorooctane sulfonate (PFOS), 3.0μg/l for perfluorononanoate (PFNA), and 1.5μg/l for perfluorohexane sulfonate (PFHxS). For PFOA, the highest 95th percentile was found at the site close to the facility (85.5μg/l), while in the control region the value was 2.4μg/l. Overall, the concentration of PFOA and PFOS declined over time in all study regions. ADONA was detected only in few samples slightly above the limit of quantification (0.2μg/l). While health risks related to ADONA are unlikely under the present exposure situation, the exposure to PFOA via tap water should be reduced markedly, especially for the population living close to the plant.

Electron microscopic investigation and elemental analysis of titanium dioxide in sun lotion

OBJECTIVE

The objective of this research was to determine the size, shape and aggregation of titanium dioxide (TiO₂ ) particles which are used in sun lotion as UV-blocker.

METHODS

Overall, six sunscreens from various suppliers and two reference substances were analysed by electron microscopy (EM) techniques in combination with energy dispersive X-ray spectroscopy (EDS). Because of a high fat content in sun lotion, it was impossible to visualize the TiO₂ particles without previous EM sample preparation. Different defatting methods for TiO₂ from sun screens were tested. A novel sample preparation method was developed which allowed the characterization of TiO₂ particles with the help of EM and EDS.

RESULTS

Aggregates of titanium dioxide with the size of primary particles varying between 15 and 40 nm were observed only in five products. In the sun lotion with the highest SPF, only few small aggregates were found. In the sun screen with the lowest SPF, the largest aggregates of TiO₂ particles were detected with sizes up to 1.6 μm. In one of the sun lotions, neither TiO₂ nor ZnO was found in spite of the labelling. Instead, approx. 500 nm large diamond-shaped particles were observed. These particles are composed of an organic material as only carbon was detected by EDS.

CONCLUSION

A novel defatting method for sample preparation of titanium dioxide nanoparticles used in sun cosmetics was developed. This method was applied to six different sun lotions with SPF between 30 and 50+. TiO₂ particles were found in only five sunscreens. The sizes of the primary particles were below 100 nm and, according to the EU Cosmetic Regulation, have to be listed on the package with the term 'nano'.

Built and socioeconomic neighbourhood environments and overweight in preschool aged children. A multilevel study to disentangle individual and contextual relationships

BACKGROUND

Structural factors of neighbourhood environments in which children live have attracted increasing attention in epidemiological research. This study investigated whether neighbourhood socioeconomic position (SEP), public playground and park space, and perceived environmental exposures were independently associated with overweight in preschool aged children while simultaneously considering individual child and family factors.

METHODS

Body-Mass-Index (BMI) data from 3499 children (53% boys and 47% girls) from three surveys between 2004 and 2007 from 18 school enrolment zones in the city of Munich, Germany, were analysed with hierarchical logistic regression models. An index of neighbourhood SEP was calculated with principal component analysis. Individual socioeconomic data, parental BMI, birth weight, housing characteristics, and perceived annoyance due to exposures to noise, air pollution, lack of greenspace, and traffic were collected with parental questionnaires. Measures of age-specific playground space and availability of park space derived from Geographic Information System were additionally weighted with age-specific population data.

RESULTS

In bivariate analysis perceived annoyance due to exposures to noise or lack of greenspace, high frequency of lorries, traffic jam, living in a multiple dwelling or next to a main road, low neighbourhood SEP, and low playground space were significantly associated with overweight. However, in multivariate analysis only living in a multiple dwelling was independently associated with overweight. From the considered individual child and family factors low parental education, parental overweight or obesity, and a high birthweight showed an independent relation to overweight.

CONCLUSIONS

Our study identified individual child and parental factors, and living in a multiple dwelling as the strongest predictors for overweight in preschool aged children. However, perceived annoyance to built environmental exposures additionally explained overweight variance between neighbourhoods. Based on our findings interventions and policies addressing overweight prevention in young children should focus on parental behaviours and the immediate home environment.

Neighbourhood socioeconomic context, individual socioeconomic position, and overweight in young children: a multilevel study in a large German city

BACKGROUND

The context of the close neighbourhood environment in which children live has gained increasing attention in epidemiological research. This study aimed to investigate if contextual neighbourhood socioeconomic position (SEP) was independently associated with overweight in young children aged 5-7 years while simultaneously considering a wide range of individual socioeconomic determinants and known risk factors for overweight.

METHODS

Objectively measured body mass index (BMI) data from 3499 children (53 % boys and 47 % girls) from three surveys between 2004 and 2007 clustered in 18 school enrolment zones in the city of Munich, Germany, were analysed with hierarchical logistic regression models. An index of neighbourhood SEP was calculated with principal component analysis using aggregated data. Individual socioeconomic data, maternal BMI, and birth weight were collected with parental questionnaires. We analysed how much of the between neighbourhood variance of overweight was attributable to individual factors and how much was explained by neighbourhood SEP.

RESULTS

The prevalence of overweight, including obesity, was 14.1 %. In the final adjusted model low neighbourhood SEP was independently associated with overweight (odds ratio (OR) = 1.42, 95 % confidence interval (CI) = 1.00-2.00) compared to high neighbourhood SEP. On the individual level low parental education (OR = 1.99, 95 % CI = 1.49-2.65) or middle parental education (OR = 1.50, 95 % CI = 1.16-1.95) compared to high parental education and nationality of the child other than German (OR = 1.53, 95 % CI = 1.17-1.99) compared to German nationality were independently associated with overweight.

CONCLUSIONS

Whereas individual determinants were the main drivers in explaining between neighbourhood variance, neighbourhood SEP additionally explained differences in overweight between neighbourhoods. Thus, considering neighbourhood context in intervention planning could result in more effective strategies compared to measures only focusing on individual determinants of overweight.

A Simple Pharmacokinetic Model of Prenatal and Postnatal Exposure to Perfluoroalkyl Substances (PFASs)

Most children are exposed to perfluoroalkyl substances (PFASs) through placental transfer, breastfeeding, and other environmental sources. To date, there are no validated tools to estimate exposure and body burden during infancy and childhood. In this study, we aimed to (i) develop a two-generation pharmacokinetic model of prenatal and postnatal exposure to perfluorooctanoic acid (PFOA), perfluorooctanesulfonate (PFOS), and perfluorohexanesulfonate (PFHxS); and to (ii) evaluate it against measured children's levels in two studies. We developed a pharmacokinetic model consisting of a maternal and a child compartment to simulate lifetime exposure in women and transfer to the child across the placenta and through breastfeeding. To evaluate the model, we performed simulations for each mother-child dyad from two studies in which maternal PFAS levels at delivery and children's PFAS levels were available. Model predictions based on maternal PFAS levels, sex of child, body weight, and duration of breastfeeding explained between 52% and 60% of the variability in measured children's levels at 6 months of age and between 52% and 62% at 36 months. Monte Carlo simulations showed that the daily intake through breastfeeding and resulting internal PFAS levels can be much higher in nursing infants than in mothers. This pharmacokinetic model shows potential for postnatal exposure assessment in the context of epidemiological studies and risk assessment.

Persistent and emerging pollutants in the blood of German adults: Occurrence of dechloranes, polychlorinated naphthalenes, and siloxanes

Human biomonitoring is a valid method to determine exposure, identify time trends, and monitor the effects of restrictions and measures. To characterize the recent exposure of Germans to persistent or emerging substances, we analyzed 4 dechloranes, 33 polychlorinated naphthalenes (PCNs), and 3 cyclic volatile methyl siloxanes (cVMS) in 42 plasma samples. The samples were collected from blood donors on a random selection. The median values of both Dechlorane Plus (DDC-CO) isomers were 1.23ng/gl.w. for anti- and 0.77ng/gl.w. for syn-DDC-CO. The two other dechloranes were found at lower levels. The median level of ∑-PCNs was 575pg/gl.w. (range: 101-1406pg/gl.w.). On average, the levels of PCNs in plasma were dominated by the congeners CN73, CN66/67, and CN51, which were responsible for approximately 71% of the total amount of PCNs. The cVMS octa-, deca-, and dodecamethylcyclotetrasiloxane could be determined in only some samples, with maximum values of 0.73, 0.48, and 0.79μg/l, respectively. Regarding dechloranes, our results are similar to those from other western countries but slightly lower than results from China. The levels of PCNs in German blood are similar to those observed in the U.S.A., but considerably lower than those reported for Korea. Using a preliminary TEF (toxic equivalency factor), the mean TEQ of the 9 quantifiable PCNs in Germany was low (0.36pg TEQ/gl.w.). The PCN levels in our study group are lower compared to previous studies.

Environmental noise and incident mental health problems: A prospective cohort study among school children in Germany

BACKGROUND

Environmental noise is considered a threat to public health as 20% of the EU population is exposed to health influencing noise levels. An association of noise and mental health problems in children has been suggested by some studies, but results are not consistent and there are no longitudinal studies of this association. Our aim was to investigate the influence of different environmental noise sources at children's homes on incident mental health problems in school-aged children.

METHOD

A cohort study of children from first (t0) to fourth grade (t1) of primary school was conducted. Different environmental noise sources (day/night separately) at children's home were assessed via parental annoyance reports. Increased noise exposure between t0 and t1 was the exposure variable. Incident mental health problems were assessed with the parental version of the Strengths and Difficulties Questionnaire (SDQ). RRs and 95% CIs were analysed to investigate the association between different noise sources and incident mental health problems.

RESULTS

The study population consisted of 583 boys and 602 girls. The most common increase in noise exposure between t0 and t1 was road traffic noise day (26.38%). After adjusting for covariates exposure to road traffic night was significantly associated with the total difficulties score (RR=2.06; 95% CI=1.25-3.40), emotional symptoms (RR=1.69, 95% CI=1.04-2.72), and conduct problems (RR=1.57, 95% CI=1.04-2.38). Noise by neighbours during the day was associated with conduct problems (RR=1.62, 95% CI=1.11-2.40) and hyperactivity (RR=1.69, 95% CI=1.08-2.65). Aircraft noise day and construction work day were not associated with any of the SDQ categories at a significant level.

CONCLUSION

Environmental noise is an important public health problem. This is the first study to investigate the association of a broad range of noise sources and incident mental health problems in children in a cohort study. Our results suggest that exposure to noise at children's home is associated with mental health problems such as emotional symptoms, conduct problems and hyperactivity.

Neutral polyfluorinated compounds in indoor air in Germany--the LUPE 4 study

Perfluoroalkyl- and polyfluoroalkyl-substances (PFAS) have been detected in many types of environmental media and biota including humans. We determined volatile PFAS, including fluorotelomer alcohols (FTOHs), fluorotelomer acrylates (FTACs), perfluorooctane sulfonamides (FOSAs), and perfluorooctane sulfonamidoethanols (FOSEs), in indoor air of residences and schools in Germany. FTOHs, FTACs, FOSEs, and FOSAs were quantified with median levels in schools (in residences) of 11,783pg/m(3) (13,198pg/m(3)), 737pg/m(3) (450pg/m(3)), 130pg/m(3) (278pg/m(3)), and 243pg/m(3) (110pg/m(3)), respectively. Using our data and previously published results in a simplified model based on the medians and 95th percentiles, the "typical" and "high" daily non-dietary exposures were calculated to be 4.2ng/kg body weight (9.9ng/kgb.w.) for Σ-FTOHs and 0.1ng/kgb.w. (0.8ng/kgb.w.) for Σ-FOSEs/FOSAs in children. Inhalation was the dominant intake pathway for FTOHs; however, dust ingestion contributed significantly to the total intake of FOSEs/FOSAs. In organisms, 8:2 FTOH is degraded to perfluorooctanoate (PFOA). Assuming that 1% of 8:2 FTOH is converted to PFOA, 8:2 FTOH exposure in Germany has a negligible contribution to the total daily PFOA exposure, which is mainly driven by dietary intake.

Monocyclic and bicyclic monoterpenes in air of German daycare centers and human biomonitoring in visiting children, the LUPE 3 study

To investigate the assumed association between indoor air pollution with monoterpenes (MTps) and the internal MTp exposure of occupants, a comparative study was performed in daycare centers in two federal states of Germany. Three well-known monoterpenoid air pollutants, viz. α-pinene (αPN), Δ(3)-carene (CRN), and R-limonene (LMN), were measured in indoor air in 45 daycare centers. Additionally, urine samples of 222 children visiting these facilities were collected in the evening after a full-day stay. Altogether 11 MTp metabolites were analyzed in the urine samples using a novel highly sensitive and selective gas chromatographic-tandem-mass spectrometric procedure. The medians (95th percentiles) of the MTp levels in indoor air were 9.1 μg m(-3) (94 μg m(-3)) for LMN, 2.6 μg m(-3) (13 μg m(-3)) for αPN, and <1.0 μg m(-3) (3.2 μg m(-3)) for CRN. None of the day care centers exceeded the German health precaution or hazard guide value. In spite of the low MTp air exposure, the urine analyses revealed an exposure to the three monoterpenes in almost all children. The median levels of MTp metabolites in urine were 0.11 mg L(-1) for LMN-8,9-OH, 0.10 mg L(-1) for LMN-1,2-OH, 49 μg L(-1) for PA, 2.9 μg L(-1) for POH, 5.2 μg L(-1) for tCAR, and 4.1 μg L(-1) for cCAR (LMN metabolites), 7.2 μg L(-1) for MYR, 19 μg L(-1) for tVER, and 19 μg L(-1) for cVER (αPN metabolites), as well as 8.2 μg L(-1) for CRN-10-COOH (CRN metabolite). Statistically significant and strong correlations among the urinary metabolites of each MTp were found. Moreover, statistical associations between LMN metabolites and the LMN indoor air levels were revealed. However, the weakness of the associations indicates a considerable impact of other MTp sources, e.g. diet and consumer products, on the internal exposure.