Heavy Metal Contamination and Remediation in Asian Agricultural Land

This paper reviews contamination status, sources and remediation of heavy metals in agricultural land of most Asian countries, with an emphasis to China, which are undergoing rapid economic development. Some farmland soil in suburbs of most cities and sewage irrigation district in China are polluted to some extend with heavy metals such as Cd, As, Zn, Cu, and Hg, consequently resulting in metal contamination of agricultural products and pose a potential risk to human health. It has been reported that foodstuff such as vegetable, grain and domestic animal feed are severely contaminated with heavy metals in the Asian countries. The sources of heavy metals in arable lands in most Asian countries include natural source, mining, smelting, agrochemicals and sewage sludge applications, and livestock manure uses. Systematic remediation technologies for contaminated soils are addressed as well, which include physical/chemical remediation, phytoremediation, microbial remediation and integrated remediation.