Polybrominated diphenyl ethers in student dormitory microenvironments: Concentrations, sources, and human exposure.

Microenvironments, such as student dormitories, differ from general residential environments. They are characterized by small spaces, poor air circulation, high personnel densities, and electronic products, such as computers that are turned on for extended periods, leading to increased pollution concentrations. The limited space and poor air circulation reduce migration of contaminants, such as polybrominated diphenyl ethers (PBDEs), making it easier for PBDEs to accumulate. However, few studies have been conducted on small group dwellings, including student dormitory dwellings. We collected dust samples from student dormitories of a university to analyze the characteristics and traceability of PBDEs in dormitory microenvironments. The results showed that PBDE congeners were widely present in university dormitories and the order of median concentration of ∑10PBDEs was as follows: male old-fashioned dormitory (273 ng/g) > female four-person dormitory (132 ng/g) > female two-person dormitory (132 ng/g) > male two-person dormitory (96.2 ng/g) > female old-fashioned dormitory (91.6 ng/g) > male four-person apartment (51.8 ng/g). BDE-209 was the most abundant PBDE congener, followed by BDE-47, and BDE-28. PBDEs were also found in typical electrical appliances, with higher concentrations in laptops than in desktops, and higher concentrations in desktops than in idle ones. According to Spearman correlation and Principal Component Analysis (PCA), we also found that boards and wallpaper materials were common sources of contamination in the microenvironment of student dormitories, and that female dormitories had more sources of PBDE emissions. Human exposure to PBDEs in students is below the US Environmental Protection Agency reference dose. Although exposure to PBDEs generated in dormitories does not pose a significant health risk, the potential hazards of PBDEs to the reagent environment remain to be investigated.

Distribution and source of and health risks associated with polybrominated diphenyl ethers in dust generated by public transportation.

Carcinogenic and neurotoxic polybrominated diphenyl ethers (PBDEs) are environmentally ubiquitous and have been widely investigated. However, little is understood regarding their pollution status, sources, and potential risk to persons in public transportation microenvironments (PTMs). We collected 60 dust samples from PTMs and then selected four materials typical of bus interiors to determine the sources of PBDEs in dust using principal component analysis coupled with Mantel tests. We then evaluated the risk of PBDEs to public health using Monte Carlo simulations. We found that PBDE concentrations in dust were 2-fold higher in buses than at bus stops and that brominated diphenyl ether (BDE)-209 was the main pollutant. The number of buses that passed through a bust stop contributed to the extent of PBDE pollution, and the primary potential sources of PBDEs in dust were plastic handles and curtains inside buses; BDE-209 and BDE-154 were the main contributors of pollution. We found that health risk was 8-fold higher in toddlers than in adults and that the reference doses of PBDEs in dust were far below the United States Environmental Protection Agency limits. Our findings provide a scientific basis that may aid in preventing PBDE pollution and guiding related pollution management strategies in PTMs.

Pollution characteristics and source identification of PBDEs in public transport microenvironments.

Public transport microenvironments easily accumulate pollutants due to high airtightness and poor circulation. To investigate and analyze the pollution levels and sources of polybrominated diphenyl ethers (PBDEs), air and dust samples were collected from hybrid buses, electric buses and subways in Hangzhou, China. The components of six priority control PBDE congeners (BDE-28, -47, -99, -100, -153, and -209) were analyzed. The average concentrations of Σ6PBDEs in the air and dust samples were 625.38 pg/m3 and 1200.58 ng/g from hybrid buses; 747.46 pg/m3 and 1160.07 ng/g from electric buses; and 407.57 pg/m3 and 925.93 ng/g from subways, respectively. Decabromodiphenyl ether (BDE-209) was the main proportion of Σ6PBDEs in the air and dust samples. Several types of materials were collected from the interior as samples to investigate pollutant sources. Using principal component analysis (PCA), it was found that seat cover, polyvinyl chloride (PVC) plastic, rubber, and wire shells were the primary sources. Compared with the reference dose of several PBDE congeners proposed by the U.S. Environmental Protection Agency (US EPA), the exposure level of the population in public transport microenvironments to PBDEs was estimated to be low; however, the potential danger cannot be ignored.

Polybrominated diphenyl ethers from automobile microenvironment: Occurrence, sources, and exposure assessment.

To investigate the level of polybrominated diphenyl ether (PBDE) contamination in the automobile microenvironment, air and dust samples were collected from 15 family automobiles in Hangzhou City, China. The PBDE concentrations, distribution of congeners, and human exposure were determined; and the content and distribution of PBDEs in automotive interior materials were analyzed. The results revealed that the average and median concentrations of ∑14PBDEs in the air in automobiles were 732 and 695 pg/m3, respectively, whereas those in automotive dust were 4913 and 5094 ng/g, respectively. Decabromodiphenyl ether (BDE-209) had the highest proportion, accounting for 61.3% and 88.8% of the ∑14PBDEs in the air and dust, respectively. The potential primary sources of PBDEs in automobile air and dust were volatile polyurethanes in seat covers and foot pads, respectively. Human exposure calculations revealed that infants and toddlers in cars were most exposed to air and dust, respectively. BDE-47 and -99 were the primary sources of health risks related to air and dust in cars.