Generic assessment criteria for human health risk management of agricultural land scenario in Jiangsu Province, China

Abstract

The widespread of agricultural soil pollution in China is posing great risks to food safety and human health. Lack of human health-based generic assessment criteria (GAC) for Chinese agricultural land makes it impossible to efficiently screen and assess the risks unless site-specific risk assessments being carried out, which are both time-consuming and costly. This paper has thus derived the first set human health-based generic assessment criteria (GAC) for 13 substances of concern (including isomers) using the CLEA model for agricultural land scenario in Jiangsu province of China. As there is no authoritative human health risk assessment model in China yet, this paper has determined and demonstrated the applicability of the CLEA model to Chinese agricultural land exposure scenarios. The derived GAC are generally less stringent than the current two Chinese standards (i.e. GB 15618-2018, GB36600-2018) for most substances except for five substances (including cadmium, nickel, alpha-HCH, beta-HCH and gamma-HCH) for which the oral background intake accounts for 50% of the Total Daily Intake. This indicates that the two Chinese soil quality standards maybe over conservative, and oral background intake (i.e. MDIoral) can be a critical parameter when deriving regional GAC for Chinese agricultural land scenarios. Since there is a notable regional difference in MDIoral for some of the substances of concern, as well as in the vegetable consumption rates and vegetable varieties consumed, it is considered necessary to derive GAC for other provinces of China for agricultural land scenario, to further examine the sensitivity of MDIoral on GAC. In addition, the 13 substances of concern in this paper are some of the most prevalent contaminants in agricultural soils in China, but GAC for some emerging new contaminants, such as thallium, vanadium, should also be derived in further research.

Keywords: Agricultural land; CLEA model; China; Generic Assessment Criteria; Jiangsu Province.