Abstract:

Cadmium contamination of soils poses a hazard to safety quality of agricultural products and brings about harmful effects on ecoenvironment and human health. It is, therefore, of important significance to develop reasonable standards for Cd in soil environment in China to the enhancement of management of Cadmium contamination in soil environment. A total of 156 data concerning soil environment standards (SESs) for cadmium (Cd) pollution were gathered 〖JP〗from 52 regions in 16 countries and 2 international organizations. By taking into consideration the types of land use suitable to the standards, SESs for Cd pollution in 32 tracts of agricultural land, 70 tracts of residential land and 56 tracts of industrial (and commercial) land were analyzed. Results show that: (1) Grade II criteria for Cd of the “Standard for soil environmental quality” GB 15618-1995, of China applicable to agricultural lands, are more stringent than the international SESs for agricultural lands; (2) the riskbased remediation goals for rural residential, urban residential lands of the Hong Kong Special Administrative Region of China are more flexible than the international SESs for residential land, while the standards for soil Cd monitoring and Cd contamination control in nonagricultural land in Taiwan region are generally lower than the median value of the international counterparts; (3) Grades A and B criteria of the Standard for Soil Quality Assessment of Exhibition Sites [HJ 350-2007 (interim)] of China are more stringent than their respective international counterparts for industrial (and commercial) land; and (4) the variation in SESs from different countries and regions may be attributed to differences in objectives of and technical methodology used for developing SESs for soil Cd, differences in acceptable risk levels and toxicity parameter values of cadmium, differences in land use patterns and assumption of associated exposure scenarios and differences in human health risk assessment models and parameters. This study aims to provide technical support for developing/revising the SESs for Cd in soils for different land uses in China.

Key words: soil, cadmium (Cd), environmental quality standard, criteria, guideline, screening value, risk assessment