Health Risk Assessment Related to Inhalation Exposure of BTEX in Ambient Air of Major Intersections in Hanoi City

Abstract

BTEX (Benzene, Toluene, Ethylbenzene, Xylene) are a cause of concern because they are potential carcinogens and adversely affect human health. In urban areas, BTEX pollution in the air comes mainly from vehicles. In this study, 24-hour sampling was conducted in dry and rainy seasons to determine the level of BTEX in the air of major intersections in Cau Giay and Dong Da Districts, Hanoi. Samples were taken at center of the intersections and three distances from the center, i.e., 20, 50 and 100 m. The concentrations of B/T/E/X at O Cho Dua (Dong Da) intersection were 0.21-32.69/ 19.43-159.74/0.27-33.45/0.44- 89.69 μg/m³, respectively; at the intersection of Xuan Thuy (Cau Giay) 0.55-14.16/3.17-107.04/0.86-24.41/1.06-53.01 μg/m³, respectively. Health risks for adults living near intersections were identified. The risk of carcinogenicity with regard to benzen > 1 part per million (regulated by CALEPA), the risk to health of toluen < 1. People living within 20-meter radius may be exposed more frequenty to BTEX through respiration. The risk to health is therefore more obvious. Effects of BTEX on health were lower at the distances of 50 and 100 m from intersection centers.