Toxicity and accumulation of arsenic in wheat (Triticum aestivum L.) varieties of China Toxicidad y acumulación de arsénico en variedades de trigo (Triticum aestivum L.) en China

Soil arsenic contamination becomes a potential ag- ricultural and environmental hazard worldwide, and has been a serious problem for safe food production. A field experiment on soil contamination was conducted on four wheat varieties ( Jimai, Gaoyou, Weimai and Wennong) in Eastern China, using 50 or 100 mg arsenic/kg soil. Biomass production and yield components were determined and arsenic concentrations were measured in plant tis- sues. Differential arsenic effects on wheat varieties were determined at maturity. Results showed that addition of arsenic significantly (p stems > leaves and rachises > grains > glumes > awns. In the arsenic treatments, arsenic concentrations in bran were about 2-3 times higher than those in flour. Most of the arsenic contaminated flour exceeded the Chinese tolerance limit. Arsenic contents of grain parts were dependent on variety and treat- ment level in polluted soils. Weimai and Wennong showed highest amounts of arsenic in flour than the other varieties at 50 or 100 mg/ kg soil treatment, respectively. Weimai possessed significantly lower (p<0.05) amount of arsenic in bran than any other wheat variety. Re- sults showed significant variety differences in arsenic concentration in polluted areas; it is of outstanding importance that wheat with the lowest possible arsenic concentration is used for food or fodder production. The present results provide scientific basis for revising the standards of wastewater discharges.