Probabilistic risk assessment of inhalation of nickel-rich soil particulates on Jeju Island, Korea

Abstract

ABSTRACTThe soils of Jeju Island contain naturally abundant nickel originating from prehistoric volcanic activity. Nickel is a known human carcinogen via inhalation exposure. A risk assessment of soil particle inhalation was conducted for the first time in Korea through the analysis of soil and air data obtained from agricultural sites. Sixteen sites in Jeju were selected—13 farms, 2 citrus orchards, and 1 ranch. Forty-four soil samples were taken from these sites and analyzed for nickel content. Total suspended solids (TSP) and particulate matter up to 10 µm in size (PM10) were measured directly from the agricultural sites, and nickel concentrations in TSP and PM10 were quantified for use in the inhalation risk assessment. We conducted a probabilistic inhalation risk analysis using monitoring data obtained from the 16 sites on Jeju Island. Risk assessment procedures followed both the Korean Ministry of Environment and the U.S. Environmental Protection Agency (USEPA) risk assessment methodologies. The cancer risk associated with inhalation followed by application of the Korean risk assessment approach ranged from 4.98 × 10−9 to 3.43 × 10−7, whereas the cancer risk associated with inhalation followed by application of the USEPA risk assessment approach ranged from 3.40 × 10−9 to 3.74 × 10−7. This study demonstrates that no carcinogenic risk is associated with inhalation in Jeju, based on a lower cancer risk limit of 10−6.