Correction: Degen et al. Citrinin Exposure in Germany: Urine Biomarker Analysis in Children and Adults. Toxins 2023, 15, 26

In the original publication [...].

Citrinin Exposure in Germany: Urine Biomarker Analysis in Children and Adults

Citrinin (CIT), a mycotoxin known to exert nephrotoxicity, is a contaminant in food and feed. Since CIT contamination is not regularly analyzed, data on its occurrence and especially levels in food commodities are insufficient for conducting a conventional exposure assessment. Yet, human biomonitoring, i.e., an analysis of CIT and its metabolite dihydrocitrinone (DH-CIT) in urine samples allows to estimate exposure. This study investigated CIT exposure in young (2-14 years) and adult (24-61 years) residents of three federal states in Germany. A total of 179 urine samples from children and 142 from adults were collected and analyzed by a targeted LC-MS/MS based method for presence of CIT and DH-CIT. At least one of the biomarkers was detected and quantified in all urines, which indicated a widespread dietary exposure to the mycotoxin in Germany. Interestingly, the biomarker concentrations of CITtotal (sum of CIT and DH-CIT) were higher in children's urine (range 0.05-7.62 ng/mL; median of 0.54 ng/mL) than in urines from adults (range 0.04-3.5 ng/mL; median 0.3 ng/mL). The biomarker levels (CITtotal) of individual urines served to calculate the probable daily CIT intake, for comparison to a value of 0.2 µg/kg bw/day defined as 'level of no concern for nephrotoxicity' by the European Food Safety Authority. The median exposure of German adults was 0.013 µg/kg b.w., with only one urine donor exceeding this provisional tolerable daily intake (pTDI) for CIT. The median exposure of children was 0.05 µg/kg bw per day (i.e., 25% of the pTDI); however, CIT exposure in 12 individuals (6.3% of our study group) exceeded the limit value, with a maximum intake of 0.46 µg/kg b.w. per day. In conclusion, these results show evidence for non-negligible exposure to CIT in some individuals in Germany, mainly in children. Therefore, further biomonitoring studies and investigations aimed to identify the major sources of CIT exposure in food commodities are required.

[Preparedness on Assaults with Highly Toxic Substances in Public Space]

The use of chemical substances in terrorist scenarios is to be feared everywhere, especially in the western world, after the events that have become known in recent years. In order to protect civilian populations in an emergency, it is essential that the poisoning pattern (toxidrome) is recognized as quickly and reliably as possible through further training of the relevant agents and the provision of necessary rescue equipment (antidotes) in prepared facilities. In the event of a chemical attack with terrorist motivation, doctors from the Public Health Service (PHS) will foreseeably play a key role in communicating with decision-makers and the public a spart of a competency network.

Polychlorinated dioxins and dibenzofurans (PCDD/F), polybrominated dioxins and dibenzofurans (PBDD/F), polychlorinated biphenyls (PCB), polybrominated diphenyl ethers (PBDE), and per- and polyfluoroalkyl substances (PFAS) in German breast milk samples (LUPE 8)

Most organic pollutants (POP) are persistent in the environment, accumulate in fatty tissues, and so a transfer through the food chain is probably, thereby causing various health effects. We quantified PCDD/F, PBDD/F, PCB, PBDE, perfluorinated substances, and ADONA in breast milk samples collected in two German federal states and breast milk and blood samples from subjects additionally exposed to PFOA. The median (95th percentile) concentrations were 2.43 (6.58) pgWHO₂₀₀₅TEQ/g l.w. for PCDD/F, 2.45 (4.82) pgWHO₂₀₀₅TEQ/g l.w. for dioxin-like PCB (dl-PCB), and 0.62 (2.69) pgWHO₂₀₀₅TEQ/g l.w. for PBDD/F. The relative contributions of the median values of PCDD/F, dl-PCB, and PBDD/F to the total-TEQ were approximately 41%, 42%, and 11%, respectively. Nondioxin-like PCB (ndl-PCB) concentrations were clearly dominated by the higher chlorinated PCB congeners, with medians of 23.2 ng/g l.w. for PCB 153, 13.9 ng/g l.w. for PCB 138, and 13.0 ng/g l.w. for PCB 180. The sum of the 3 congeners (PCB 138, 153, and 180) were multiplied with 1.64 (total PCB) and showed a median of 82.16 ng/g l.w. and a 95th percentile of 173.3 ng/g l.w. Only PFOA and PFOS could be quantified in 29% and 17% of in total 180 samples with 95th percentiles of 53 ng/l and 33 ng/l, respectively. Milk samples (n = 13) from subjects living on PFOA contaminated sites showed higher levels between 33 and 854 ng/l PFOA (mean: 199 ng/l), whilst PFOS could be quantified only in three samples. The sum of 17 PBDE congeners showed medians (95th percentile) of 1737 pg/g l.w. (22,806 pg/g l.w.), with the highest medians of 422 pg/g l.w. for BDE 209 and 378 pg/g l.w. for BDE 153. Overall, our study confirms the declining contamination level in breast milk during the last decade, but points out the need to further reduce the environmental contamination with persistent substances and subsequently the exposure in childhood.

The oral bioavailability of di-2-ethylhexyl phthalate (DEHP), di-isononyl phthalate (DiNP) and di-(isononyl)-cyclohexane-1,2-dicarboxylate (DINCH®) in house dust

Phthalates and other plasticizers are detected in high amounts in the indoor environment and therefore house dust can be an exposure source. Especially children have a relatively high unintended uptake of house dust, thus a higher exposure to plasticizers compared to adults may be possible. As accurate as possible exposure assessment data of the oral bioavailability of these compounds are necessary, however only one in vivo study with piglets is available so far. The aim of this study was to examine the oral bioavailability of phthalates and DINCH® in humans, which occur in typical house dust samples. We focused on the high molecular weight phthalates DEHP and DINP and their substitute DINCH®. Eleven volunteers ingested 6 g of house dust sieved to 2 mm. The urine was collected over a period of 36 h. The excreted plasticizers metabolites were quantified by an LC-MS/MS method. The mean recovery of urine metabolites was 51 % ± 20 % for DEHP, 26 % ± 13 % for DINP and 19 % ± 6% for DINCH® based on the parent compounds administered as dust samples. The metabolites of DEHP, DINP and DINCH® reached their maximum concentration after 2-19 hours post dose in urine. The bioavailability of DEHP was in agreement among the different dust samples. For DEHP, we were able to confirm previous findings from the oral bioavailability study with piglets and we could not observe a significant difference between the dust particle size (65 μm vs 2 mm) and the bioavailability. Considering the observed bioavailability, an estimated dust intake of 50 mg/d for toddlers can substantially contribute to the total plasticizer exposure.

Time trend of exposure to dechloranes: Plasma samples of German young adults from the environmental specimen bank collected from 1995 to 2017

Dechloranes, like Dechlorane Plus® are commonly used flame retardants identified by the EU as substances of very high concern (SVHC) because of their persistence and bioaccumulation potential. To characterize the dechlorane exposure of Germans in the last two decades, 180 archived blood plasma samples of the German Environmental Specimen Bank (students aged 20-29 years) collected at six time points between 1995 and 2017 were analyzed for four dechloranes; namely Dechlorane Plus® (syn- and anti-DDC-CO), dechlorane 602 (DDC-DBF), and dechlorane 603 (DDC-Ant). These were quantified using a GC-MS/MS method. Overall, anti- and syn-DDC-CO were detected in 88% and 98% of the samples, whereas DDC-DBF and DDC-Ant were found in 40% and 37% of the samples, respectively. The median (95th percentile) values were 1.0 ng/g lipid weight (l.w.) (3.0 ng/g l.w.). for anti-DDC-CO, 0.6 ng/g l.w (1.9 ng/g l.w.). for syn-DDC-CO, 0.1 ng/g l.w (0.6 ng/g l.w.). for DDC-DBF, and 0.1 ng/g l.w (0.2 ng/g l.w.). for DDC-Ant. The 95th percentile concentrations of the sum of syn- and anti-DDC-CO decreased from 4.2 ng/g l.w. in 1995, to 2.9 ng/g l.w. in 1999, and subsequently increased to 3.7 ng/g l.w. in 2008, and up to 5.9 ng/g l.w. in 2017. A statistically significant decrease with time was observed for DDC-DBF and DDC-Ant, but not for DDC-CO. Our medians found in blood samples in 2017 are similar to those observed in Germany in 2013/14, but higher compared to values reported in other European countries. Overall, more toxicological and monitoring data is needed to better characterize the potential impact on health.

Internal exposure to perfluoroalkyl substances (PFASs) and biological markers in 101 healthy 1-year-old children: associations between levels of perfluorooctanoic acid (PFOA) and vaccine response

Perfluoroalkyl substances (PFASs) are a complex group of man-made chemicals with high stability and mobility leading to ubiquitous environmental contamination and accumulation in the food chain. In human serum/plasma samples, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are the lead compounds. They are immunotoxic in experimental animals, and epidemiological studies provided evidence of a diminished production of vaccine antibodies in young children. However, information on children of the first year of age is missing but relevant, as they have a relatively high exposure if breastfed, and may have a higher susceptibility as their immune system is developing. In a cross-sectional study with 101 healthy 1-year-old children, internal levels of persistent organic pollutants and a broad panel of biological parameters were investigated at the end of the 1990s. Additional analysis of PFASs resulted in plasma levels (mean ± SD) of PFOA and PFOS of 3.8 ± 1.1 and 6.8 ± 3.4 µg/L, respectively, in the 21 formula-fed children, and of 16.8 ± 6.6 and 15.2 ± 6.9 µg/L in the 80 children exclusively breastfed for at least 4 months. The study revealed significant associations between levels of PFOA, but not of PFOS, and adjusted levels of vaccine antibodies against Haemophilus influenza type b (Hib, r = 0.32), tetanus (r = 0.25) and diphtheria (r = 0.23), with no observed adverse effect concentrations (NOAECs) determined by fitting a 'knee' function of 12.2, 16.9 and 16.2 µg/L, respectively. The effect size (means for PFOA quintiles Q1 vs. Q5) was quantified to be - 86, - 54 and - 53%, respectively. Furthermore, levels of PFOA were inversely associated with the interferon gamma (IFNɣ) production of ex-vivo lymphocytes after stimulation with tetanus and diphtheria toxoid, with an effect size of - 64 and - 59% (means Q1 vs. Q5), respectively. The study revealed no influence of PFOA and PFOS on infections during the first year of life and on levels of cholesterol. Our results confirmed the negative associations of PFAS levels and parameters of immune response observed in other epidemiological studies, with high consistency as well as comparable NOAECs and effects sizes for the three vaccine antibodies investigated, but for PFOA only. Due to reduction of background levels of PFASs during the last 20 years, children in Germany nowadays breastfed for a long duration are for the most part not expected to reach PFOA levels at the end of the breastfeeding period above the NOAECs determined.

Persistent Organic Pollutants in Human Breast Milk and Associations with Maternal Thyroid Hormone Homeostasis

Epidemiological studies have indicated the thyroid-disrupting effects of persistent organic pollutants (POPs). However, the association of low-exposure POPs with thyroid hormones (THs) remains unclear. Here, we aim to assess the association of low exposure of POPs, including polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), and polybrominated dibenzo-p-dioxins and furans, with THs [total _L-thyroxine (TT₄), total 3,3',5-triiodo-_L-thyronine (TT₃), and total 3,3',5'-triiodo-_L-thyronine (TrT₃)] measured in human breast milk. Ninety-nine breast milk samples were collected from the LUPE cohort (2015-2016, Bavaria, Germany). Fourteen PBDEs, 17 PCBs, and 5 PCDD/Fs had quantification rates of >80%. Nonmonotonic associations were observed. In adjusted single-pollutant models, (1) TT₄ was inversely associated with BDE-99, -154, and -196; (2) TT₃ was inversely associated with BDE-47, -99, -100, -197, -203, -207, and OCDD; and (3) TrT₃ was inversely associated with BDE-47, -99, -183, and -203. Multipollutant analysis using principal component analysis and hierarchical clustering revealed inverse associations of PBDEs (BDE-28, -47, -99, -100, -154, -183, and -197) with TT₄ and TrT₃. These results indicate that POPs at low levels might be related to reduced THs. This study shows that human breast milk might be an appropriate specimen to evaluate the thyroid disruption of POPs.

Bioavailability of phthalate and DINCH® plasticizers, after oral administration of dust to piglets

For decades, phthalates have been widely used as plasticizers in a large number of consumer products, leading to a complex exposure to humans via ingestion, inhalation or dermal uptake. Children may have a higher unintended dust intake per day compared to adults. Therefore, dust intake of children could pose a relevant exposure and subsequently a potential health risk. The aim of this study was to determine the relative bioavailability of certain phthalates, such as di(2-ethylhexyl) phthalate (DEHP), di-isononyl phthalate (DINP) and the non-phthalate plasticizer diisononyl 1,2-cyclohexanedicarboxylic acid (DINCH^®, Hexamoll^®), after ingestion of dust. Seven 5-week-old male piglets were fed five different dust samples collected from daycare centers. Overall, 0.43 g to 0.83 g of dust sieved to 63 μm were administered orally. The piglets' urine was collected over a period of 38 h. The excreted metabolites were quantified using an LC-MS/MS method. The mean uptake rates of the applied doses for DEHP, DINP, and DINCH^® were 43% ± 11%, 47% ± 26%, and 9% ± 3.5%, respectively. The metabolites of DEHP and DINP showed maximum concentrations in urine after three to five hours, whereas the metabolites of DINCH^®, reached maximum concentrations 24 h post-dose. The oral bioavailability of the investigated plasticizers was higher compared to the bioaccessibility reported from in vitro digestion tests. Furthermore, the bioavailability of DEHP did not vary substantially between the dust samples, whereas a dose-dependent saturation process for DINP was observed. In addition to other intake pathways, dust could be a source of plasticizers in children using the recent intake rates for dust ingestion.

Siloxane in baking moulds, emission to indoor air and migration to food during baking with an electric oven

Linear and cyclic volatile methylsiloxanes (l-VMS and c-VMS) are man-made chemicals with no natural source. They have been widely used in cosmetics, personal care products, coatings and many other products. As a consequence of their wide use, VMS can be found in different environmental media, as well as in humans. We bought 14 new silicone baking moulds and 3 metallic moulds from the market and used them in different baking experiments. Four of the silicone baking moulds were produced in Germany, two in Italy, four in China, and for the other moulds were no information available. The metal forms were all produced in Germany. VMS were measured in the indoor air throughout the baking process and at the edge and in the center of the finished cakes using a GC/MS system. Additionally, the particle number concentration (PNC) and particle size distribution were measured in the indoor air. The highest median concentrations of VMS were observed immediately following baking: 301 μg/m³ of D7, 212 μg/m³ of D6, and 130 μg/m³ of D8. The silicone moulds containing the highest concentrations of c-VMS corresponded with distinctly higher concentrations of the compounds in indoor air. Using a mould for more than one baking cycle reduced the indoor air concentrations substantially. Samples collected from the edge of the cake had higher concentrations relative to samples from the center, with a mean initial concentration of 6.6 mg/kg of D15, 3.9 mg/kg of D9, 3.7 mg/kg of D12, and 4.8 mg/kg of D18. D3 to D5 were measured only at very low concentrations. Before starting the experiment, an average PNC of 7300 particles/cm³ was observed in the room's air, while a PNC of 140,000 particles/cm³ was observed around the electric stove while it was baking, but this PNC slowly decreased after the oven was switched off. Baking with 4 of the moulds exceeded the German indoor precaution guide value for c-VMS, but the health hazard guide value was not reached during every experiment. Compared to other exposure routes, c-VMS contamination of cake from silicone moulds seems to be low, as demonstrated by the low concentrations of D4 and D6 measured. For less volatile c-VMS > D6 the results of the study indicate that food might play a more important role for daily intake. As a general rule, silicone moulds should be used only after precleaning and while strictly following the temperature suggestions of the producers.

[Electronic Shiazo waterpipes: a new source of indoor air pollutants]

BACKGROUND

For some time, a new form of waterpipe smoking has been advertised, where steam stones moistened with aroma fluids (Shiazo) are heated electronically. Since there is no combustion of tobacco, it is often assumed that the produced vapor is not harmful to health. To clarify this issue, we performed a comprehensive inner and outer exposure assessment during the use of an electronic Shiazo waterpipe.

METHODS

Three volunteers smoked an electronic waterpipe operated with nicotine-free Shiazo stones in a thoroughly ventilated room for 2 h. In three smoking sessions, three fluids with different flavorings were vaporized. In parallel, emissions of particles, volatile organic compounds, polycyclic aromatic hydrocarbons (PAH), and metals were measured in indoor air. Within a biomonitoring study, urinary metabolite profiles of air pollutants were checked. For comparison, the components of the Shiazo fluids were also analyzed.

RESULTS

During the smoking sessions, concentrations of formaldehyde, acetaldehyde, glycerine, and propylene glycol rose significantly in the indoor environment. The content of putative carcinogenic PAH in indoor air increased by 42% to 174 ng/m³. Particle number concentrations ranged from 39,968 to 65,610 particles/cm³ (median), with peaks at diameters from 25 to 31 nm. 3‑HPMA, the mercapturic acid metabolite of the pyrolysis product acrolein, was strongly elevated in urine samples of the smokers. All fluids contained high amounts of contact allergens.

CONCLUSIONS

Electronic Shiazo waterpipes release various harmful substances that considerably impact indoor air quality. Compared to conventional waterpipes, the release of pollutants is lower. Nevertheless, smoking with Shiazo waterpipes is a source of health risks for both users and bystanders.

Air quality in indoor go-kart facilities in Germany

Indoor go-kart driving and viewing is enjoyed by people of all ages. However, it may pose health hazards, especially for children, pregnant women, cardiovascular patients, and elderly individuals. Depending on the race length, for example, high concentrations of various contaminants may result in severe health problems. Therefore, this project investigated the Indoor Air Quality of eight indoor go-kart facilities. In general, karts that used regular fuel produced the highest concentrations of CO, benzene, TVOC, and BaP, with maximum levels up to 150 mg/m³ , 170 μg/m³ , 2690 μg/m³ , and 8.7 ng/m³ , respectively. As expected, the maximum CO concentrations at go-kart facilities that used liquid gas and electric karts (20 and <6 mg/m³ , respectively) were significantly lower than those at other facilities. The highest 95th percentile values for NO (2680 μg/m³ ) and NO₂ (280 μg/m³ ) were measured for karts with liquid gas. The alkane, alkene, and cycloalkane groups, as well as benzene and the alkyl benzenes, were the predominant components of the measured TVOCs. Overall, owners of indoor go-kart tracks should ensure that the ventilation with regard to combustion products is optimally adapted in any case to reduce the levels of critical air pollutants.

Physicochemical characterization of aerosol particles emitted by electrical appliances

Adverse health effects of airborne particulate matter depend on parameters like particle size, particle surface and chemical composition. Major emission of indoor particles is caused by combustion processes like tobacco smoking and cooking. Nevertheless, the use of household electrical appliances, such as vacuum cleaners, flat irons or hair dryers, can produce particles as well. In this study the emissions of different hair dryers and flat irons were investigated using a test chamber. The particle number concentrations, particle volume concentrations, as well as the size distributions were measured. Particles were sampled and analyzed by electron microscopy, inductively coupled plasma mass spectrometry and gas chromatography mass spectrometry. Moreover different volatile organic compounds (VOCs) were measured. Each tested appliance, especially flat irons produced small particles with diameters far below 100nm and might be a nonnegligible source for indoor particles. Copper was the main identified element in most of the particles emitted from hair dryers, but in the emission of two hair dryers silver-containing nanoparticles were found as well. Various VOCs were observed in the emission of both flat irons and hair dryers, while cyclic siloxanes were detected only in the emission of flat irons. The use of flat irons or hair dryers may significantly contribute to the personal particle exposure.

Excretion of Di-2-ethylhexyl phthalate (DEHP) metabolites in urine is related to body mass index because of higher energy intake in the overweight and obese

A higher body mass index (BMI) has been positively associated with the rate of excretion of di-2-ethylhexyl phthalate (DEHP) metabolites in urine in data from the National Health and Nutrition Examination Survey (NHANES), suggesting an association between DEHP exposure and BMI. The association, however, may be due to the association between body mass maintenance and higher energy intake, with higher energy intake being accompanied by a higher intake of DEHP. To examine this hypothesis, we ran a Monte Carlo simulation with a DEHP physiologically-based pharmacokinetic (PBPK) model for adult humans. A realistic exposure sub-model was used, which included the relation of body weight to energy intake and of energy intake to DEHP intake. The model simulation output, when compared with urinary metabolite data from NHANES, supported good model validity. The distribution of BMI in the simulated population closely resembled that in the NHANES population. This indicated that the simulated subjects and DEHP exposure model were closely aligned with the NHANES population of interest. In the simulated population, the ordinary least squares regression coefficient for log(BMI) as a function of log(DEHP nmol/min) was 0.048 (SE 0.001), as compared with the reported value of 0.019 (SE 0.005). In other words, given our model structure, the higher energy intake in the overweight and obese, and the concomitant higher DEHP exposure, describes the reported relationship between BMI and DEHP.

Occurrence of carbazoles in dust and air samples from different locations in Germany

9H-carbazole is generated from incomplete combustion of diverse fossil fuels and biomass, in tobacco smoke and from industrial processes, while halogenated carbazoles have natural and anthropogenic sources. We analyzed 9H-carbazole and 14 halogenated carbazoles in dust samples from 14 schools, 13 daycare centers, and 13 residences, as well as 5 indoor air samples from residences in Munich, Germany. Overall, we present first data of various carbazoles in different indoor environments without visible combustion sources. The median (95th percentile) values of the halogenated analytes mainly detected in the entire study group were 10.3ng/g (308ng/g) for 9H-carbazole, 13.3ng/g (735ng/g) for 3,6-dichloro-9H-carbazole, 6.2ng/g (159ng/g) for 1,3,6-tribromo-9H-carbazole, and 1.2ng/g (21.1ng/g) for 2,7-dibromo-9H-carbazole. For most of the target analytes, the highest concentrations were observed in dust samples from schools, and the lowest were found in residences. In the air samples, all analytes were found only at low levels, with median values of 7.7pg/m³ for 9H-carbazole and 6.1pg/m³ for 2,3,6,7-tetrachloro-9H-carbazole. For 9H-carbazole, "typical" and "high" non-dietary intake of children through dust ingestion using median and 95th percentile values were calculated to be 0.03ng/kg b.w. and 1.1ng/kg b.w. daily, respectively. Due to limited toxicological information and exposure data for other relevant pathways (e.g., dietary intake), the risk assessment is inconclusive. Nevertheless, there are indications that 9H-carbazole has carcinogenic properties and that halogenated carbazoles have dioxin-like toxicities. Therefore, further research is essential.

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.