Polycyclic aromatic hydrocarbon exposures of children in low-income families1

Abstract

Ž. Children in low-income families may have high exposures to polycyclic aromatic hydrocarbons PAH . Such exposures could result from household proximity to heavy traffic or industrial sources, environmental tobacco smoke, contaminated house dust or soil, among others. The objectives of this study were: to establish methods for measuring total PAH exposure of children in low-income families, to estimate the PAH exposures of these children, and to estimate the relative importance of the environmental pathways for PAH exposure. Analytical methods to determine PAH in air, dust, soil, and food and to determine hydroxy-PAH in urine samples were evaluated and validated. A two-home pilot study was conducted in downtown Durham, North Carolina Ž . NC during February 1994. One smoker's and one nonsmoker's household, which had preschool children and income at or below the official U.S. poverty level, participated. A nine-home winter and a nine-home summer study were conducted in Durham and the NC Piedmont area during February 1995 and August 1995, respectively. A summer study in four smokers' homes was also conducted. In each of these studies, multimedia samples were collected and analyzed for PAH or hydroxy-PAH. Summary statistics, Pearson correlations, and analysis of variance were performed on the combined data from these four field studies. An effective screening method was established for recruiting low-income families. The field protocol involved measurements of three homes in 2-day periods. This protocol should be suitable for large-scale studies. The results showed that indoor PAH levels were generally higher than outdoor PAH levels. Higher indoor PAH levels were observed in the smokers' homes compared to nonsmokers' homes. Higher outdoor PAH levels were found in inner city as opposed to rural areas. The relative concentration trend for PAH in dust and soil was: house dust ) entryway dust ) pathway soil. The PAH concentrations in adults' food samples were generally higher than those in children's food samples. Children's potential daily doses of PAH were higher than those of adults in the same household, when intakes were normalized to body weights. Inhalation is an important pathway for children's exposure to total PAH because of the high levels of naphthalene present in both indoor and outdoor air. Dietary ingestion and nondietary ingestion Ž pathways became more important for children's exposure to the B2 PAH ranked as probable human carcinogens, B2 by the U.S. EPA's Integrated Risk . System , most of which are of low volatility. The analysis of variance results showed that inner city participants had higher total exposure to B2 PAH than did rural participants.

Mutagenic and Carcinogenic Hazards of Settled House Dust I: Polycyclic Aromatic Hydrocarbon Content and Excess Lifetime Cancer Risk from Preschool Exposure

“…Similar results were observed in other studies where the concentrations of the B2 PAHs, were shown to be approximately one-half of the total PAH concentrations (24,50).…”

“…A small number of studies have assessed children's exposure to PAHs in SHD as compared to other matrices (22)(23)(24). These assessments show that dietary ingestion of PAHs in food is often the primary exposure pathway for children.…”

Particulate matter and polycyclic aromatic hydrocarbon concentrations in indoor and outdoor microenvironments in Boston, Massachusetts

“…Although resuspension processes largely influence coarse particles, larger particles in the PM 2.5 fraction can also be affected by resuspension ( Chow et al, 1994;Vette et al, 2001 ). PAH concentrations followed generally similar trends as PM 2.5 , with elevated concentrations mostly associated with high -traffic settings or cooking, as documented previously (Chuang et al, 1999;Dubowsky et al, 1999). For all three pollutants, we determined that outdoor concentrations are relatively poor predictors of indoor levels in short sampling periods in microenvironments.…”

An investigation of the association between traffic exposure and the diagnosis of asthma in children

“…(PAH), a product of diesel combustion, showed that children in inner cities had significantly higher exposure to PAH than did rural children (Chuang et al, 1999). High traffic exposure is a risk factor for the development of wheeze and asthma diagnoses.…”