Exposure assessment and health risk of poly-brominated diphenyl ether (PBDE) flame retardants in the indoor environment of elementary school students in Korea

Abstract

This study assessed the health risks of elementary school students' exposure to PBDEs via different possible pathways in children's facilities. After PBDE contamination was measured, exposure was demonstrated to occur through multiple routes, including inhalation of indoor dust, dermal contact with products' surfaces and children's hands, and incidental dust ingestion. Samples were collected from various children's facilities (30 elementary schools, 31 private academies, 12 living rooms and bedrooms in houses, 5 public libraries of children's literature, and 3 large hypermalls) in summer (Jul-Sep, 2008) and winter (Jan-Feb, 2009). The hazard index (HI) was estimated for non-carcinogens and PBDEs, such as TeBDE, PeBDE, HxBDE, OcBDE, and DeBDE. PBDEs were detected in all floor dust samples, 99% of indoor air samples, 94% of product-wipe samples, and 86% of hand wipe samples. The average levels of PBDEs ranged from 0.19 to 1.06 ng/m(3) in indoor air, 4623 to 6,650 ng/g-dust in floor dust, 0.012 to 0.103 ng/cm(2) on product surfaces, and 7.89 to 25.38 ng/hand on the surface of children's hands. The HI for school children via multimedia and multipathway exposure to PBDEs did not exceed 1.0. The exposure to PBDEs at home (approximately 80%) was dominant. The contribution rates of PBDE risk were 77% and 15% via dust ingestion at home and at elementary school, respectively; thus, intake of floor dust was determined to be the primary route of exposure.

Indoor Level of Polybrominated Diphenyl Ethers in the Home Environment and Assessment of Human Health Risks

“…Although several studies did not detect BDE-209 Zhang et al, 2011;Watkins et al, 2013;Bennett et al, 2014), BDE-209 was at least compositing of 50% in the environmental samples and human specimens (Chao et al, 2014a). BDE-209 was the predominant BDE congener in indoor air of various microenvironments except Korean elementary schools where the concentration of airborne BDE-47 was highest among 8 airborne BDE congeners (Lim et al, 2014). Indoor air levels of PBDEs were lower in residences including houses and apartments than in other microenvironments (Table 2).…”

“…Table 2 shows airborne PBDE concentrations in residential houses, apartments, offices, daycare centers, cars, public facilities, and schools according to currently published and the present data. The levels of airborne PBDEs in residences are lower in Taiwan than in Sweden , Vietnam (in houses near backyard electronic (e)-waste recycling sites; Tue et al, 2013), Korea (Lim et al, 2014), and the United States (Allen et al, 2007;Bennett et al, 2014), and slightly higher in Taiwan than Japan (Takigami et al, 2009), United Kingdom , Sweden (in apartments; Thuresson et al, 2012), Vietnam (in houses in suburban and rural areas; Tue et al, 2013), and Australia (Toms et al, 2009). Compared to their levels in other microenvironments listed in Table 2, PBDE levels in the houses or apartments (except Vietnamese houses near backyard e-waste recycling sites) were lower.…”

“…Health risks were assessed with the Monte Carlo simulation. Airborne PBDE levels from the present study and house dust PBDE levels from our previous study (Chao et al, 2014b) (Lim et al, 2014) was used to estimate noncancer risk in Taiwan, where DI, EF, ED, and AT nc are daily intake, exposure frequency per year (day/year), exposure duration (year), and average time for non-cancer effects during exposure duration (year), respectively. Quantitative estimates of carcinogenic risk with neurobehavioral effects via oral ingestion of BDE-209 (oral slope factor = 0.0007 per mg/Kg/day) was also obtained from IRIS (US EPA, 2008).…”

“…Several reports propose that the indoor home environment is a major source of exposure to PBDEs in humans, especially the very young who spend a lot of time at home, play on the floor, and have frequent hand-tomouth contact (Stapleton et al, 2008;Stapleton et al, 2012;Buttke et al, 2013). Lim et al (2014) indicated that the home among indoor environments was recognized as the largest contributor to daily exposure and health risk among Korean school children (daily dose: 80%, 16%, 3%, and 1% for home, elementary school, private academy, and public facility, respectively). In addition to dietary PBDE daily intake (67.95 ng/day for Taiwanese adults) (Chen et al, 2012), non-dietary PBDE daily intake (adult males: 39.2 ng/day, adult females: 41.2 ng/day) estimated in the present study is also an important source of PBDEs exposure in Taiwan.…”

Initial Evaluation of Provincial-Level Environmental Risks from the Perspective of Human Settlements

“…However, the present environmental risks are not limited to such fields as environmental toxicology, ecotoxicology, environmental pollution, and disruption of environment geology. There are many newly emerging topics, such as ecological risk assessment of elevated carbon dioxide levels in the marine environment [4], ecological risk assessment of heavy metal-polluted lakes (Morocco) [5], ecological risk assessment of rivers influenced by heavy use of antibiotics for aquaculture (Vietnam) [6], environmental risk assessment from the perspective of public health (Brazil) [7], risk assessment of indoor environments exposed to risks (Korea) [8], risk assessment of cumulative chemical exposure in urban environments (Holland) [9], environmental risk assessment based on mercury exposure (France) [10], risk assessment of the presence of pharmaceutical residues in water resources (France) [11], and medical waste and environmental health risk assessment (Mauritius) [12]. Approaches to environmental risk assessment are either qualitative or quantitative.…”