Cadmium accumulation in pak choi (Brassica chinensis L.) and estimated dietary intake in the suburb of Hangzhou city, China.

The total content of cadmium and its distribution between leaves and roots were investigated for pak choi (Brassica chinensis L.), which was grown in a contaminated area of Hangzhou city, China. Results showed that cadmium concentrations in 90% of samples exceeded the Chinese tolerance limit for food. Although roots of pak choi had a higher concentration of cadmium than leaves, leaf tissue (the edible part) accumulated over 80% (on average) of the whole plant cadmium burden due to the greater biomass in leaf tissue. Since pak choi is the staple vegetable in the study area and of great relevance to human health, the dietary intake of cadmium and calculated risk indexes to local residents through the food chain were determined.