ABSTRACT
Indoor air concentrations of formaldehyde, furfural, benzaldehyde, and 11 aliphatic aldehydes (C2 -C11 ) were measured in residences of 639 participants in the German Environmental Survey for Children and Adolescents 2014-2017 (GerES V). Sampling was conducted using passive samplers over periods of approximately seven days for each participant. The most abundant compounds were formaldehyde and hexanal with median concentrations of 24.9 µg m-3 and 10.9 µg m-3 , respectively. Formaldehyde concentrations exceeded the Guide Value I recommended by the German Committee on Indoor Guide Values (Ausschuss für Innenraumrichtwerte - AIR) (0.10 mg m-3 ) for 0.3% of the participating residences. The sum of aliphatic n-aldehydes between C4 (butanal) and C11 (undecanal) exceeded their Guide Value (0.10 mg m-3 ) for 2.0% of the residences. The geometric mean concentrations of most aldehydes were lower than in the earlier GerES IV (2003-2006) study. Formaldehyde and hexanal concentrations, however, were comparable in both studies and showed no significant difference. Indoor aldehyde concentrations did not exhibit significant correlations with factors collected in questionnaires, such as the age of the participants, their socio-economic status, the location of the residence (former East/West Germany), migration background, tobacco exposure, and the type of furniture used. The validity of the passive sampler measurements was verified against active sampling techniques in a test chamber experiment.
Subject(s)
Air Pollutants , Air Pollution, Indoor , Adolescent , Air Pollutants/analysis , Air Pollution, Indoor/analysis , Aldehydes/analysis , Benzaldehydes , Child , Environmental Monitoring/methods , Formaldehyde/analysis , Furaldehyde , Humans , Surveys and QuestionnairesABSTRACT
Exhaled aerosol particles play an important role in the transmission of SARS-CoV2, particularly when many people gather indoors. This article summarises the knowledge on virus transmission in schools and practical measures to reduce aerosol-driven infections. A central preventive measure is to enhance room and building ventilation, i.e. the exchange of possibly contaminated indoor air with ambient air. Besides the concentrations of possibly infectious particles, ventilation reduces carbon dioxide concentrations, humidity and other chemical substances in indoor air as well. Irrespective of ventilation, face masks (surgical or FFP2) represent a vital part of hygiene measures. Fixed or mobile air purifiers can support these measures particularly when rooms providing only poor ventilation must be utilized. The article reflects the state of knowledge in October 2021 of the various techniques that have been shown as useful for the prevention of indirect infections. New variants of SARS-CoV2, the progress of the vaccination campaign in children and adolescents, and the increase in general immunity might require a re-evaluation of the prevention strategies described. The COVID-19 pandemic has revealed common deficits in room and building ventilation, not least in schools. Apart from short-term measures for the prevention of airborne infectious diseases, a long-term strategy seems advisable to alleviate the deficits encountered in schools with respect to room and building ventilation. In view of a permanent improvement of indoor air and prevention against airborne infections the fitting of schools with fixed ventilation systems - preferably including heat and moisture recovery - appears to be a sustainable social investment.
Subject(s)
Air Pollution, Indoor , COVID-19 , Adolescent , Aerosols , Child , Germany , Humans , Pandemics , SARS-CoV-2 , SchoolsABSTRACT
The UV filter 4-methylbenzylidene camphor (4-MBC), used in cosmetics, the antioxidant butylated hydroxytoluene (BHT), used inter alia as a food additive and in cosmetics, and the plasticizer tris(2-ethylhexyl) trimellitate (TOTM), used mainly in medical devices as substitute for di-(2-ethylhexyl) phthalate (DEHP), are suspected to have endocrine disrupting effects. Human biomonitoring methods that allow for assessing the internal exposure of the general population to these substances were recently developed in a German cooperation to enhance the use of human biomonitoring. First-morning void urine samples from 3- to 17-year-old children and adolescents living in Germany were analysed for metabolites of 4-MBC (N = 447), BHT (N = 2091), and TOTM (N = 431) in the population-representative German Environmental Survey on Children and Adolescents 2014-2017 (GerES V). 4-MBC metabolites were found in quantifiable amounts only in single cases and exposure levels remained well below health-based guidance values. In contrast, ubiquitous exposure to BHT became evident with a geometric mean (GM) urinary concentration of the metabolite BHT acid of 2.346 µg/L (1.989 µg/gcreatinine) and a maximum concentration of 248 µg/L (269 µg/gcrea). The highest GM concentration was found in young children aged 3-5 years, yet no specific sources of exposure could be identified. Also, TOTM metabolites were found in quantifiable amounts only in very few samples. None of these findings could be related to previous hospital treatment or exposure via house dust. The presented results will be the basis to derive reference values for exposure of children and adolescents in Germany to BHT and will facilitate to identify changing exposure levels in the general population.
Subject(s)
Environmental Pollutants , Phthalic Acids , Adolescent , Benzoates , Biological Monitoring , Butylated Hydroxytoluene , Camphor/analogs & derivatives , Child , Child, Preschool , Environmental Exposure/analysis , Environmental Monitoring , Germany , HumansABSTRACT
During the population representative German Environmental Survey of Children and Adolescents (GerES V, 2014-2017) 2256 first-morning void urine samples from 3 to 17 years old children and adolescents were analysed for 21 metabolites of 11 different phthalates (di-methyl phthalate (DMP), di-ethyl phthalate (DEP), butylbenzyl phthalate (BBzP), di-iso-butyl phthalate (DiBP), di-n-butyl phthalate (DnBP), di-cyclohexyl phthalate (DCHP), di-n-pentyl phthalate (DnPeP), di-(2-ethylhexyl) phthalate (DEHP), di-iso-nonyl phthalate (DiNP), di-iso-decyl phthalate (DiDP) and di-n-octyl phthalate (DnOP)). Metabolites of DMP, DEP, BBzP, DiBP, DnBP, DEHP, DiNP and DiDP were found in 97%-100% of the participants, DCHP and DnPeP in 6%, and DnOP in none of the urine samples. Geometric means (GM) were highest for metabolites of DiBP (MiBP: 26.1 µg/L), DEP (MEP: 25.8 µg/L), DnBP (MnBP: 20.9 µg/L), and DEHP (cx-MEPP: 11.9 µg/L). For all phthalates but DEP, GMs were consistently higher in the 3-5 years old children than in the 14-17 years old adolescents. For DEHP, the age differences were most pronounced. All detectable phthalate biomarker concentrations were positively associated with the levels of the respective phthalate in house dust. In GerES V we found considerably lower phthalate biomarker levels than in the preceding GerES IV (2003-2006). GMs of biomarker levels in GerES V were only 18% (BBzP), 23% (MnBP), 23% (DEHP), 29% (MiBP) and 57% (DiNP) of those measured a decade earlier in GerES IV. However, some children and adolescents still exceeded health-based guidance values in the current GerES V. 0.38% of the participants had levels of DnBP, 0.08% levels of DEHP and 0.007% levels of DiNP which were higher than the respective health-based guidance values. Accordingly, for these persons an impact on health cannot be excluded with sufficient certainty. The ongoing and substantial exposure of vulnerable children and adolescents to many phthalates confirms the need of a continued monitoring of established phthalates, whether regulated or not, as well as of potential substitutes. With this biomonitoring approach we provide a picture of current individual and cumulative exposure developments and body burdens to phthalates, thus providing support for timely and effective chemicals policies and legislation.
