二元含Hg(Ⅱ)重金属混合物对发光细菌的联合毒性

Effects of joint toxicity of mercury and another heavy metal on luminescent bacteria

本文采用二次二因子回归通用旋转组合实验设计,以明亮发光杆菌(photobacterium phosphoreum)T3变种作为毒性测试物种,研究了Hg2++Pb2+、Hg2++Cd2+和Hg2++Cr6+等二元含Hg(Ⅱ)重金属混合物的联合毒性作用和主因子作用,建立了3个相应的数学模型。结果表明,Hg2+、Pb2+、Cd2+与Cr6+对明亮发光杆菌的毒性有显著的正效应。3个含Hg2+二元重金属混合物对发光细菌的联合毒性作用不同,总体上Hg2+与Pb2+以协同作用为主,Hg2+与Cd2+为相加作用,而Hg2+与Cr6+以拮抗作用为主。从单因子作用效应的角度看,3个混合物中对发光细菌的毒性Hg2+大于另一重金属,即Hg2+为主因子。发光细菌法作为一种快速、操作方便、成本低廉的生物监测方法,将在农产品污染物毒性评价和农产品安全快速检测中有着广泛的应用前景。

The joint toxicity effects of heavy metals on luminescent bacteria Photobacterium phosphoreum T3 were investigated. The joint and integral toxicity of Mercury, Plumbum, Cadmium and Chromium were tested by oceanic luminous bacteria. The concentrations of each kind of heavy metal in mixture were determined by a statistical method called general regression circumrotate experimental design and the test results were analyzed using software such as SAS, MINTAB etc. Three function models were built which showed that the toxicity of each heavy metal on luminescent bacteria was usually in positive effect. The effects of toxicity on bacteria vary through concentration of heavy metals in mixtures. As for the three kinds of mixtures containing Mercury the binary toxicity of mixtures was different from each other. Generally, the binary toxicity of Mercury and Plumbum is synergism. The binary toxicity of Mercury and Cadmium is only addictive, and the binary toxicity of Mercury and Chromium is antagonism. From the view of single heavy metal effect, the toxicity effects of Mercury are outweighed over the other metal in mixture. The determination of joined toxicity of various kinds of mixture of pollutants using luminescent bacteria is a rapid, cheap and easy biological method which can be used widely in the assessment of farm product pollution and the detection of products safety in the future.