Characteristics and evaluation of heavy metal (Pb and Zn) contamination on vegetables grown in the suburbs of Huanggang, China

Vegetables are the extremely important life-supporting materials for human beings. However, many vegetables are contaminated by heavy metals. No published data are available on heavy metal concentrations in Huanggang City, Hubei Province, China. This study focused on characteristics and evaluation on heavy metal (Pb and Zn) concentrations in vegetables grown in the suburbs of Huanggang. Several important vegetable bases in the suburbs of Huanggang were employed as study areas, 63 representative vegetable samples, including leaf vegetables, melon-fruit vegetables, root-stem vegetables and bean vegetables, were collected to determine the contents of heavy metal Pb and Zn using atomic absorption spectrophotometer (Varian, AA240FS, USA). The status of Pb and Zn concentrations were analyzed and evaluated according to Chinese Food and Health National Standard. The results showed that vegetables grown in the city were seriously contaminated by heavy metal Pb; the pollution degree differed from vegetable varieties, leaf-, root- and stem-vegetables were contaminated mostly, followed by bean- and melon-fruit-vegetables. Vegetables grown in the area were not contaminated by heavy metal Zn. It is strongly recommended that the local government of Huanggang City should pay much more attention to the vegetable contamination by heavy metals in the city. The reason why heavy metal Pb polluted seriously and how to prevent it in the city need to be further studied.