Non-phthalate plasticizers in German daycare centers and human biomonitoring of DINCH metabolites in children attending the centers (LUPE 3).

Plasticizers have been widely used for decades as additives in diverse applications, including consumer and building products, toys, cables, and floorings. Due to toxicological concerns and restrictions of different dialkyl ortho-phthalates, other plasticizers have been increasingly used in recent years. Therefore, di-isononyl cyclohexane-1,2-dicarboxylate (DINCH), di(2-ethylhexyl) terephthalate (DEHT), di(2-ethylhexyl) adipate (DEHA), acetyl tri-n-butyl citrate (ATBC), and trioctyl trimellitate (TOTM) plasticizer levels in indoor air and dust samples from 63 daycare centers in Germany were measured. Moreover, the urine samples of 208 children who attend 27 of these facilities were analyzed for the presence of four DINCH metabolites. DINCH, DEHT, and DEHA were present in indoor air with median values of 108 ng/m(3), 20 ng/m(3), and 34 ng/m(3), respectively. Median values of 302 mg/kg for DINCH, 49 mg/kg for DEHA, 40 mg/kg for DEHT, and 24 mg/kg ATBC were found in dust. In the urine samples, the three secondary metabolites of DINCH were observed with median values (95th percentiles) of 1.7 µg/l (10.0 µg/l) for OH-MINCH, 1.5 µg/l (8.0 µg/l) for oxo-MINCH, and 1.1 µg/l (6.1 µg/l) for cx-MINCH. Overall, these metabolite levels are orders of magnitude lower than the current HBM I values set by the German Human Biomonitoring Commission. Using general exposure assumptions, the intake resulting from dust ingestion and inhalation is low for children. The total daily DINCH intake calculated from biomonitoring data was 0.5 µg/kg b.w. using median values and 9.8 µg/kg b.w. as the maximum value. At present, non-phthalate plasticizers, especially DINCH, can be found in considerable amounts in dust samples from daycare centers and as DINCH metabolites in the urine of children. In relation to previous studies, the concentrations of DINCH in dust and urine have an increasing time trend. Compared with tolerable daily intake values, the total daily intake of DINCH reached only 1% of its maximum value to date; however, due to its increased use, higher exposure of DINCH is expected in the future.

Organophosphate flame retardants and plasticizers in the air and dust in German daycare centers and human biomonitoring in visiting children (LUPE 3).

Organophosphate (OP) flame retardants and plasticizers are chemicals that have been used in large quantities in diverse consumer and building-related products for decades. In the present study, OPs were measured in paired indoor air and dust samples from 63 daycare centers in Germany. Moreover, the urine of 312 children between 22 and 80 months old who attend these facilities was analyzed for the presence of eight OP metabolites. Tri-(2-butoxyethyl)-phosphate (TBEP), tris-(2-chloroisopropyl) phosphate (TCPP), and tri-n-butyl-phosphate (TnBP) were present in low concentrations in indoor air, with median values of 49 ng/m(3), 2.7 ng/m(3), and 2.2 ng/m(3), respectively. In dust, median values of 225 mg/kg for TBEP, 2.7 mg/kg for TCPP, 1.1mg/kg for diphenyl(2-ethylhexyl) phosphate, and 0.5mg/kg for tri-phenyl-phosphate (TPhP) were found. In the urine samples, the metabolites di-phenyl-phosphate, di-n-butyl-phosphate, and di-(2-butoxyethyl)-phosphate had median values (95th percentiles) of 0.8 µg/l (4.0 µg/l), 0.2 µg/l (0.9 µg/l), and 2.0 µg/l (10.7 µg/l), respectively. A significant correlation was found between the dust and air samples in the levels of TnBP, tris(2-chloroethyl) phosphate (TCEP), and TBEP. For TCEP and TBEP, significant correlations were also observed between the levels in dust and the respective metabolite levels in urine. For TCEP, there was also a significant correlation between the concentration in indoor air and metabolite levels in urine. Based on the 95th percentile in dust and air in our study and data from residences in a previously published study, the daily intake of the most abundant OP (TBEP) is high (i.e., 3.2 µg/kg b.w.). This level is approximately 6.4% of the reference dose (RfD) established by the NSF, U.S.A. Overall, our study shows that daycare centers are indoor environments that contribute to OP exposure.

Phthalates in German daycare centers: occurrence in air and dust and the excretion of their metabolites by children (LUPE 3).

Phthalates have been used for decades in large quantities, leading to the ubiquitous exposure of the population. In an investigation of 63 German daycare centers, indoor air and dust samples were analyzed for the presence of 10 phthalate diesters. Moreover, 10 primary and secondary phthalate metabolites were quantified in urine samples from 663 children attending these facilities. In addition, the urine specimens of 150 children were collected after the weekend and before they went to daycare centers. Di-isobutyl phthalate (DiBP), dibutyl phthalate (DnBP), and di-2-ethylhexyl phthalate (DEHP) were found in the indoor air, with median values of 468, 227, and 194ng/m(3), respectively. In the dust, median values of 888mg/kg for DEHP and 302mg/kg for di-isononyl phthalate (DiNP) were observed. DnBP and DiBP were together responsible for 55% of the total phthalate concentration in the indoor air, whereas DEHP and DiNP were responsible for 70% and 24% of the total phthalate concentration in the dust. Median concentrations in the urine specimens were 44.7µg/l for the DiBP monoester, 32.4µg/l for the DnBP monoester, and 16.5µg/l and 17.9µg/l for the two secondary DEHP metabolites. For some phthalates, we observed significant correlations between their concentrations in the indoor air and dust and their corresponding metabolites in the urine specimens using bivariate analyses. In multivariate analyses, the concentrations in dust were not associated with urinary metabolite excretion after controlling for the concentrations in the indoor air. The total daily "high" intake levels based on the 95th percentiles calculated from the biomonitoring data were 14.1µg/kg b.w. for DiNP and 11.9µg/kg b.w. for DEHP. Compared with tolerable daily intake (TDI) values, our "high" intake was 62% of the TDI value for DiBP, 49% for DnBP, 24% for DEHP, and 9% for DiNP. For DiBP, the total daily intake exceeded the TDI value for 2.4% of the individuals. Using a cumulative risk-assessment approach for the sum of DEHP, DnBP, and DiBP, 20% of the children had concentrations exceeding the hazard index of one. Therefore, a further reduction of the phthalate exposure of children is needed.

[The occurrence of plasticisers (phthalates) in communal facilities under special consideration of results from LUPE 3]. / Vorkommen von Weichmachern (Phthalaten) in Gemeinschaftseinrichtungen unter besonderer Bedeutung der Ergebnisse von LUPE 3.

Children are a very susceptible subgroup of the general population and therefore health authorities have a special interest to prevent them from health hazards. In a study of 3 German Bundesländer the indoor air and dust samples of altogether 63 German daycare centres were analysed for the presence of phthalate diesters in 2011/12 (LUPE 3 study). Inhalable dust and gas phases were collected with a glass fibre filter and polyurethane foam over approximately 6 h while children were attending these facilities. Settled dust was collected by vacuuming the floor of the room using an ALK dust sampler. Indoor air and dust were analysed using a GC/MS system. Median values in the dust samples were 888 mg/kg for di-2-ethylhexyl phthalate (DEHP), 302 mg/kg for diisononyl phthalate (DiNP), 34 mg/kg for diisodecyl phthalate (DiDP), 21 mg/kg for di-n-butyl phthalate (DnBP), and 20 mg/kg for diisobutyl phthalate (DiBP). For DEHP and DiNP maximum values of 10,086 mg/kg and 7,091 mg/kg were observed, respectively. DEHP and DiNP were responsible for 70% and 24% of the total phthalate concentration in the dust. In indoor air phthalates are found mainly in the particulate phase of the filters. Only the more volatile phthalates dimethyl phthalate and diethyl phthalate were found also in the gas phase. The median values in the indoor air were 470 ng/m³ for DiBP, 230 ng/m³ for DnBP, 190 ng/m³ for DEHP, and 100 ng/m³ for DiNP. DnBP and DiBP were together responsible for 55% of the total phthalate concentration in the indoor air. Overall, our study showed that the concentrations of phthalates in indoor air of daycare centers are slightly higher and in dust samples lower compared with schools.

Effect of classroom air quality on students' concentration: results of a cluster-randomized cross-over experimental study.

UNLABELLED: To assess the effect of indoor air quality as indicated by the median carbon dioxide (CO2) level in the classroom on the concentration performance (CP) of students, a cross-over cluster-randomized experimental study was conducted in 20 classrooms with mechanical ventilation systems. Test conditions 'worse' (median CO2 level on average 2115 ppm) and 'better' (median CO2 level on average 1045 ppm) were established by the regulation of the mechanical ventilation system on two days in one week each in every classroom. Concentration performance was quantified in students of grade three and four by the use of the d2-test and its primary parameter 'CP' and secondary parameters 'total number of characters processed' (TN) and 'total number of errors' (TE). 2366 d2-tests from 417 students could be used in analysis. In hierarchical linear regression accounting for repeated measurements, no significant effect of the experimental condition on CP or TN could be observed. However, TE was increased significantly by 1.65 (95% confidence interval 0.42-2.87) in 'worse' compared to 'better' condition. Thus, low air quality in classrooms as indicated by increased CO2 levels does not reduce overall short-term CP in students, but appears to increase the error rate. PRACTICAL IMPLICATIONS: This study could not confirm that low air quality in classrooms as indicated by increased CO2 levels reduces short-term concentration performance (CP) in students; however, it appears to affect processing accuracy negatively. To ensure a high level of accuracy, good air quality characterized, for example, by low CO2 concentration should be maintained in classrooms.

Elemental carbon and respirable particulate matter in the indoor air of apartments and nursery schools and ambient air in Berlin (Germany).

UNLABELLED: This study was performed to examine exposure to typical carcinogenic traffic air pollutants in the city center of an urban area. In all, 123 apartments and 74 nursery schools were analyzed with and without tobacco smoke interference and the households in two measuring periods. Simultaneously, the air outside 61 apartment windows as well as the average daily traffic volume were measured. Elemental carbon (EC), the marker for particulate diesel exhaust and respirable particulate matter (RPM) were determined. The thermographic EC analysis was conducted with and without prior solvent extraction of the soluble carbon fraction. Comparison of these two thermographic EC measurements clearly showed that method-related differences in the results, especially for indoor measurements, when high background loads of organic material were present (e.g. tobacco smoke), existed. Solvent extraction prior to EC determination was therefore appropriate. For the first winter measuring period, the EC concentration levels without solvent extraction in the indoor air were about 50% higher than those measured in the spring/summer period. In the second measuring period (i.e. spring/summer), the median EC concentrations after solvent extraction were 1.9 microg/m3 for smokers' apartments and 2.1 microg/m3 for non-smokers' apartments, with RPM concentrations of 57 and 27 microg/m3, respectively. Nursery schools showed high concentrations with median values of 53 microg/m3 for RPM and 2.9 microg/m3 for EC after solvent extraction. A significant correlation between the fine dust and EC concentrations (after solvent extraction) in the indoor and ambient air was determined. Outdoor EC values were also correlated with the average daily traffic volume. The EC ratios between indoor and ambient concentration showed a median of 0.8 (range: 0.3-4.2) in non-smoker households and 0.9 (range: 0.4-1.5) in smoker apartments. Furthermore, the EC/RPM ratio in indoor and ambient air was 0.01-0.15 (median 0.06) and 0.04-0.37 (median 0.09), respectively. PRACTICAL IMPLICATIONS: In the absence of indoor sources a significant correlation with regard to respirable particulate matter (RPM) and elemental carbon concentrations between the indoor and ambient air of apartments was observed. The high degree of certainty resulting from this correlation underscores the importance of ambient air concentrations for indoor air quality. In nursery schools we found higher concentrations of RPM. An explanation of these results could be the high number of occupants in the room, their activity and the cleaning intensity.

Occurrence of organotin compounds in house dust in Berlin (Germany).

In a study in the year 2000 on the occurrence of hazardous environmental contaminants house dust samples from 28 Berlin apartments were measured for the presence and concentrations of six organotin compounds, monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), monooctyltin (MOT), dioctyltin (DOT) and triphenyltin (TPT). The concentrations of MBT and DBT determined ranged considerably from 0.01 mg kg-1 to 1.5 mg kg-1 (median: 0.05 mg kg-1) and 0.01 to 5.6 mg kg-1 (median: 0.03 mg kg-1), respectively. Maximum levels of TBT and MOT were only 0.08 mg kg-1 and 0.04 mg kg-1. The maximum total value of the organotins was 7.2 mg kg-1 (median: 0.11 mg kg-1). MBT was found in 86% and DBT in 82% of the samples above the limit of quantification, TBT and MOT only in 50% and DOT in 43%. The focus of ecotoxicology is on the risks arising from organotin compounds (especially butyltins) when used as biocides in antifouling paints. TBT acts as an endocrine disrupter in animals, inducing masculinization (imposex) in female gastropods of different species by increasing testosterone levels. The most critical organ site in experimental animals is the cellular immune system, where lymphocyte depletion in the thymus and peripheral lymphoid tissues takes place. Our study does not provide data on the basis of which population exposure could be estimated; house dust containing harmful organotins could, however, under some conditions, become a relevant intake possibility for young children.

Polycyclic aromatic hydrocarbons inside and outside of apartments in an urban area.

In the context of environmental monitoring in Berlin polycyclic aromatic hydrocarbon (PAH) concentrations in air and household dust were measured inside 123 residences (and simultaneously in a sub group in the air outside the windows). The aim of this study was to determine exposure to PAHs in the environment influencing by several factors, for instance, motor vehicle traffic in a populous urban area. Indoor air samplings were carried out in two periods (winter and spring/summer) in smokers and non-smokers apartments. Benzo(a)pyrene (BaP) median values were 0.65 ng m(-3) (winter) and 0.27 ng m(-3) (spring/summer) in smokers' apartments and 0.25 ng m(-3) (winter) and 0.09 ng m(-3) (spring/summer) in the apartments of non-smokers. The median BaP content in ambient air was 0.10 ng m(-3) (maximum: 1.1 ng/m(-3)) with an indoor-outdoor mean concentration ratio of 0.9 in non-smoker households and 5.4 in smoker apartments. In household dust we obtained median values of 0.3 mg kg(-1) (range: 0.1-1.4 mg kg(-1)). We found a significant relation between indoor and outdoor values. Approximately 75% of the variance of indoor air values was caused by the corresponding BaP concentrations in the air outside the apartment windows. Otherwise a significant correlation between indoor air and household dust values cannot be found. Therefore, according to our results, it is suggested that the indoor PAH concentration in non-smoker apartments could be attributed mainly to vehicular emissions.

Occurrence of phthalates and musk fragrances in indoor air and dust from apartments and kindergartens in Berlin (Germany).

UNLABELLED: In this study, the occurrence of persistent environmental contaminants room air samples from 59 apartments and 74 kindergartens in Berlin were tested in 2000 and 2001 for the presence of phthalates and musk fragrances (polycyclic musks in particular). These substances were also measured in household dust from 30 apartments. The aim of the study was to measure exposure levels in typical central borough apartments, kindergartens and estimate their effects on health. Of phthalates, dibutyl phthalate had the highest concentrations in room air, with median values of 1083 ng/m(3) in apartments and 1188 ng/m(3) in kindergartens. With around 80% of all values, the main phthalate in house dust was diethylhexyl phthalate, with median values of 703 mg/kg (range: 231-1763 mg/kg). No statistically significant correlation could be found between air and dust concentration. Musk compounds were detected in the indoor air of kindergartens with median values of 101 ng/m(3) [1,3,4,6,7,8-hexahydro-4,6,6,7,8,8- hexamethylcyclopenta-(g) 2-benzopyrane (HHCB)] and 44 ng/m(3) [7-acetyl-1,1,3,4,4,6-hexamethyl-tetraline (AHTN)] and maximum concentrations of up to 299 and 107 ng/m(3) respectively. In household dust HHCB and AHTN were detected in 63 and 83% of the samples with median values of 0.7 and 0.9 mg/kg (Maximum: 11.4 and 3.1 mg/kg) each. On comparing the above phthalate concentrations with presently acceptable tolerable daily intake values (TDI), we are talking about only a small average intake [di(2-ethylhexyl) phthalate and diethyl phthalate less than 1 and 8% of the TDI] by indoor air for children. The dominant intake path was the ingestion of foodstuffs. For certain subsets of the population, notably premature infants (through migration from soft polyvinyl chloride products), children and other patients undergoing medical treatment like dialysis, exchange transfusion, an important additional intake of phthalates must taken into account. PRACTICAL IMPLICATIONS: The phthalate and musk compounds load in a sample of apartments and kindergartens were low with a typical distribution pattern in air and household dust, but without a significant correlation between air and dust concentration. The largest source of general population exposure to phthalates is dietary. For certain subsets of the general population non-dietary ingestion (medical and occupational) is important.

Influence of solvents and gas chromatographic injector conditions on the detectability of nitroaromatic compounds.

We investigated the influence of four common solvents and of several liner packings of a split/splitless injector on the gas chromatographic behavior of trinitrotoluenes and related nitroaromatic compounds. The highest peaks are observed using toluene in combination with an empty liner or with a prepacked CarboFrit liner. In particular, the peaks of trinitrotoluene isomers and 1,3,5-trinitrobenzene significantly decreased or even totally disappeared when using quartz wool or glass wool, even when treated with dimethylchlorosilane. Similiar peak reductions are obtained with methanol or acetonitrile. Effects of decreasing peak are accompanied by the formation of two additional products when using methanol.

Polycyclic aromatic hydrocarbons (PAH) and diesel engine emission (elemental carbon) inside a car and a subway train.

Significant concentrations of potentially harmful substances can be present in the interior of vehicles. The main sources of PAHs and elemental carbon (EC) inside a car are likely to be combustion emissions, especially from coal and traffic. The same sources can also be important for the interior of a subway train for which there are specific sources in the tunnel system, for example diesel engines. Twice, in summer 1995 and winter 1996 polycyclic aromatic hydrocarbons (PAH) and diesel motor emission (estimated as elemental carbon) were determined in the interior of a car (a 2-year-old VW Golf with a three-way catalytic converter) and in the passenger compartment of a subway train (below ground). On each sampling day (in total 16 daily measurements in the car and 16 in the subway) the substances were determined in the breathing zone of the passengers from 07:00 h to 16:00 h under different meteorologic conditions (winter- and summertime). The car followed the route of the subway from the western Berlin borough of Spandau to the south-eastern borough of Neukölln, and back. The sampling represented a realistic exposure model for driving in a high traffic and polluted urban area. The electric subway train (also 2 years in use) connected the same parts of Berlin (31 km underground). The mean values obtained during the two measurement periods (summer/winter) inside the car were 1.0 and 3.2 ng/m3 for benzo[a]pyrene, 10.2 and 28.7 ng/m3 for total-measured-PAHs, 14.1 and 8.2 micrograms/m3 for EC and in the subway 0.7 and 4.0 ng/m3 for benzol[a]pyrene, 30.2 and 67.5 ng/m3 for total PAHs, 109 and 6.9 micrograms/m3 for EC. A comparison between subway and car exposures shows significantly higher concentrations of PAHs in the subway train, which can be explained by relatively high concentrations of fluoranthene and pyrene in the subway. So far a satisfactory explanation has not been found, but one source might be the wooden railway ties which were formerly preserved with tar based products. In wintertime in both transportation systems the concentrations of beno[a]pyrene are three to four times higher than in summer corresponding to the changing of the ambient air concentrations.

[Exposure of the population to volatile organic compounds inside an automobile and a subway train]. / Exposition der Bevölkerung gegenüber flüchtigen Luftschadstoffen im Autoinnenraum und in der U-Bahn.

Air quality, in particular in urban regions, is affected by the emissions of the traffic and meanwhile for some substances motor vehicles became the dominating source. For valid quantitative risk assessment of the general population it is necessary to have informations about the main routes of exposure. Therefore in a pilot study 1994 and two times in summer 1995 and winter 1996 aromatic hydrocarbons, carbon monoxide (CO) and carbon dioxide (CO2) were determined under different meteorologic conditions inside of a car (a two year old VW-Golf with a three-way catalyst) and in a subway-train. The car route followed the subway (31 km underground) and crossed the central parts of Berlin in streets with high traffic density. The mean values for benzene obtained during the three measurement periods inside the car were 21.1/21.5 and 21.6 micrograms/m3 (daily maximum: 31.9/26.3 and 35.0 micrograms/m3) and inside the subway 8.4/5.4 and 7.4 micrograms/m3 (daily maximum: 16.0/7.4 and 10.3 micrograms/m3). The mean levels of CO in the car were 6 ppm (summer) and 5 ppm (winter) respectively, with peak concentrations of 33 and 70 ppm (10-minutes maximum). In the subway the values were 2 ppm (summer and winter); (10-minutes maximum: 5 and 12 ppm). A comparison between the two types of traffic shows three times higher concentrations of benzene inside the car. Our results demonstrate that the exposure of car occupants to benzene has to be taken into account for risk assessment. The concentration of CO inside the car is three to four times higher than in the subway train. Compared with other studies we found only low concentrations of CO inside the car.