Study On The Urine Safety Critical Value Of 16 Vegetable Soils In Fujian

The contents of mercury in the vegetables and the corresponding surface soils (≤15cm) collected from some agricultural fields in the suburbs of12counties of Fujian Province were investigated. The Hg accumulation and its availability in the soils and the influencing factors, and the accumulation of Hg in the edible parts of different vegetable varieties from the soils were studied. The security thresholds of soil Hg for the vegetable varieties were then calculated. The main results were as follows:1. The contents of total soil Hg ranged between0.038and1.807mg.kg"1with the average being0.283mg.kg-1and those of available soil Hg were between0.003and0.095mg.kg-1with a mean of0.021mg.kg-1.2. The Hg concentrations (FW) of the edible parts of the vegetables varied between0.02and22.65μg.kg-1. Root vegetables and leafy vegetables contained higher levels of Hg than the others while yaro vegetables, beans vegetables, cabbage vegetables had lower concentrations of Hg than the others. The correlation between the Hg concentrations of the vegetables and the available Hg in the soils were better than those between the Hg concentrations in the vegetables and the total soil Hg.3. Different vegetables showed different capacity to absorb Hg from the soils. The capacity of absorbing Hg from the soils of the vegetables were generally in the order of root vegetables and some of the leafy vegetables> aquatic vegetables, melons, some leafy vegetables and root tuber vegetables> solanaceae, cabbage, beans and some root tuber vegetables.4. The accumulation coefficients of soil Hg for most vegetables significantly and negatively correlated with the total soil Hg or the available soil Hg, showing that the accumulation coefficients for the vegetables tended to decrease with increasing soil Hg contents. The correlations between the accumulation coefficients based on the available soil Hg and the available soil Hg were better than those between the accumulation coefficients based on the total soil Hg and the total soil Hg.5. The security thresholds expressed in available soil Hg (mg· kg-1) for the various vegetables calculated according to the above results were celery (0.06), radish (0.06), spinach (0.06), lettuce (0.07), sweet potato (0.19), mustard (0.19), pakchoi (0.31), cowpea (0.65), cabbage (1.29), tomatoes (6.13), pepper (22.11). the corresponding security thresholds expressed in total soil hg (mg· kg-1) were:celery (0.36), radish (0.37), spinach (0.38), lettuce (0.41), sweet potato (0.74), mustard (0.74), pakchoi (1.09), cowpea (2.10), cabbage (3.97), tomatoes (18.15), pepper (64.97).