Prediction and early-warning for health safety of lead in soil and vegetable system，the Pearl River Delta Plain, southern China

In Shunde District of Foshan City, Pearl River Delta Economic Zone, 208 topsoil samples and 114 vegetable samples were collected from vegetable fields to measure the contents of lead (Pb) ，which species of 38 topsoil samples were extracted. The results showed that the average concentration of heavy metal Pb was 44.3mg/kg. The contents of soil lead that exceeded Guangdong Province soil background values accounted for 77.5%, , the content of lead in vegetable that exceeded safety requirements for non-environ