对粤西某硫酸厂周边农田的农作物及其种植土壤中重金属Tl的含量分布、潜在生态风险进行了探讨。结果表明,硫酸厂周边农作物及其种植土壤均受到了Tl污染,其中作物种植土壤中Tl的含量变化范围为3.76~7.24mg·kg^-1,表现出中度以上的Tl污染和较高程度的潜在生态风险;Tl在6种不同农作物中的含量变化范围为20.69~176.7mg·kg^-1,表现出明显的生物富集效应。其中番薯中Tl的富集系数最大,为26.9;油麦菜中Tl的富集系数最小,为4.11。农作物中Tl的健康风险评价表明,在硫酸厂周边农田种植的作物中除毛豆外,其余的农作物可食用部分中Tl的危险商(HQ)值均大于1.0,食用这些农作物将可能对人体产生健康风险,应当引起足够的重视。
The distribution and potential ecological risk of thallium in six vegetables and arable soils taken from a sulfuric acid plant in western Guangdong Province were investigated in this paper. The concentrations of thallium in sweet potato, lettuce, eggplant, dasheen, green soy bean and leaf lettuce were 176.7, 110.0, 56.3, 20.69, 51.2, 22.2 mg·kg-1, respectively; While the concentrations of thallium in arable soils were 6.56, 7.24, 4.27, 5.03, 3.76, 5.32 mg·kg-1, respectively. The Single Factor Pollution Index and the Single Factor Potential Pollution index were in the range of 2.05~3.96 and 82.0~158, respectively. The potential ecological risk assessment indicated thallium pollution in arable soils around the sulfuric acid plant was moderate or severe. Furthermore, the bio-concentration factor of thallium in the crops were in the range of 4.11~26.9, which in sweet potato and leaf lettuce were the maximum and minimum value respectively. The aforementioned results revealed that the crops and their arable soils around the sulfuric acid factory were both contaminated by thallium and vegetables showed significant bioaccumulation effect on thallium. Basing on the health risk assessments, the hazard quotients(HQ) of the crops except green soy bean were all above 1.0. Therefore, much attention should be paid to consume these Tl contaminated vegetables which may cause great potential risks.