校园学生群体食物汞暴露现状及风险评价——以天津大学为例

通过测定校园学生主要食物中(包括主食、鱼类、肉类、蔬菜等)总汞和甲基汞浓度,同时采集志愿者头发作为生物指示物,结合外暴露和内暴露数据系统评估学生群体的汞暴露风险.校园食堂食物总汞浓度范围为0.57~207.50ng/g(以湿重计),甲基汞浓度范围为0.06~49.20ng/g(以湿重计),与已有研究相比处于较低水平.不同食物中汞浓度水平存在显著差异,如水产品中总汞和甲基汞浓度均比其他食物要高.所调查人发中总汞浓度为0.03~0.77 μg/g,甲基汞浓度为0.02~0.67 μg/g,男性发汞浓度要显著高于女性.人体汞浓度与个人饮食习惯存在一定联系,水产品食用频次较高的人群中发汞浓度也相对较高.男性学生总汞摄入量约为9200ng/d,女性约为7500ng/d.总汞摄入主要通过主食摄入,而甲基汞则主要通过水产品摄入.根据现行人群汞摄入风险评价标准,本研究中校园人群汞暴露风险较低,但水产品食用频次增加仍可能造成大量的汞摄入.

Food mercury exposure and risk assessment of the students in the campus

Mercury concentrations in the daily food (including staple food, fish, meat and vegetables) consumed in the TJU campus were investigated. Mercury levels in the hair of the volunteers were also analyzed. Total mercury (THg) and methylmercury (MeHg) concentrations in foods ranged 0.57~207.50ng/g (wet weight) and 0.06~49.20ng/g (wet weight) respectively, and were lower than the previous studies. The mercury concentrations varied among foods, and higher THg and MeHg concentrations were observed in the seafood. THg and MeHg levels in the human hair ranged from 0.03~0.77 and 0.02~0.67 μg/g, respectively, and the concentrations in the males were significantly higher than the females. Dietary habits have an impact on the hair mercury concentrations. The daily mercury exposure from food consumption was 9200ng/d for males and 7500ng/d for females. Compared with the current limit of mercury exposure, the risk imposed to the campus residents were low. However, excessive consumption of seafood could still be an important source of mercury for the consumers.