Abstract:

In this study, soil samples were collected from a largescale coal chemical industry area in Northwest China. And then arsenic (As) in soil samples was detected by novel collision/reaction cell technology (CCT) of inductively coupled plasma mass spectrometry (ICPMS, collectively ICPCCTMS) after closed vessel microwave digestion. Human health risks of As for three different gasification units were evaluated in three major exposure pathways, including inhalation particles, skin contact and ingestion of soil particles. Results showed that the comprehensive carcinogenic risk of As in coal chemical industry area soils is 6.159.24 times the acceptable risk level, and the hazard quotient of different coal chemical industry area is acceptable. The main exposure route of As in coal chemical industry area soils is ingestion of soil particles, which can account for 68.64% of total carcinogenic risk. Considering different control values by each exposure pathway, the minimum control value (1.59 mg/kg) in the pathway of ingestion of soil particles, which also have a maximum contribution to the carcinogenic risk could be selected as the strict reference of safety threshold for As in soil environment in coal chemical industry area. Combining the characteristics of coal chemical industry in China, background value of As in regional soil, regional climate and geological characteristics, etc., and taking into account the difference of the acceptable level of human health risk of As in different countries and regions and feasibility, the safety threshold of As in the soil environment of certain coal chemical industry could be comprehensively determined.

Key words: carcinogenic risk, hazard quotient, coal chemical industry, arsenic, soil, safety threshold