Research Program Area: Health & Exposure
Topic Areas: Indoor Air Quality
As part of an earlier California Air Resources Board (CARB) contract (Agreement Number 08-305), we measured VOCs in single-day air samples collected in 2010-2011 from 40 early childhood education (ECE) facilities in California. We observed numerous unknown peaks in the gas chromatography-mass spectrometry (GC/MS) chromatographs for indoor samples. We verified identification of 119 of these non-targeted compounds using automated mass spectral de-convolution and identification software (AMDIS) and mass spectral libraries. We also ran 14 pure standards for selected chemicals, and the results of retention times and probability-based matching indicated that the 14 compounds were correctly identified, confirming the general validity of the method used to identify unknown VOCs. Estimated exposures to naphthalene exceeded age-adjusted “safe harbor levels” based on California’s Proposition 65 guidelines (10-5 lifetime cancer risk) in 97% of the facilities, as did several compounds described in the parent report (benzene, chloroform, ethylbenzene, formaldehyde, and acetaldehyde). While exposures to 17 of the VOC compounds we measured were below non-cancer health benchmarks, more than 70% of the compounds lacked any health-based exposure standards that could be used to assess potential risks. Through extensive review of databases aggregating toxicological information and the application of quantitative structure–activity relationship (QSAR) modeling methods, we identified 12 chemicals that warrant additional exposure and health evaluation due to their potential for carcinogenic, neurologic, or other health effects (acetic acid, butyl ester; camphor; octamethylcyclotetrasiloxane (D4); D5; n-heptane; heptanal; d-limonene; n-pentane; 3-phenyl-2-propenal; α-pinene; α-terpineol; and 1,2,4-trimethylbenzene). These chemicals include commonly used terpenes and fragrance-related compounds, which have been associated with respiratory or other health problems. Given the seriousness of the health risks associated with the VOC levels we observed, our findings demonstrate that potentially harmful VOC exposures are occurring in ECE environments and indicate that more research is needed to fully assess the potential health risks to young children and adult staff and identify major sources of VOCs present in ECE facilities. If warranted, restrictions on the use of some compounds should be considered as well as outreach to child care providers on strategies to improve indoor air quality, such as ensuring proper ventilation, to mitigate these exposures.
For questions regarding this research project, including available data and progress status, contact: Research Division staff at (916) 445-0753
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