Comparison of organics and heavy metals acute toxicities to Vibrio fischeri

Abstract

Vibrio fischeri bioluminescence inhibition has been widely used to test acute toxicities of metals and organics contaminants. However, the differ­ences of metals and organics acute toxicities to V. fischeri have not been com­pared. Here, four heavy metals (Zn²⁺, Cu²⁺, Cd²⁺ and Cr⁶⁺) and five organics (phenol, benzoic acid, p-hydroxybenzoic acid, nitro-benzene and benzene) acute toxicities to V. fischeri were investigated. Heavy metals toxicities to V. fischeri were increased along with the reaction time, while the organics toxi­cities kept the same level in different reaction times. In order to explain the dif­ference, the relative cell death rate of V. fischeri was detected. In metals toxi­cities tests, the bioluminescence inhibition rate of V. fischeri was found to be significantly higher than the relative cell death rate (P < 0.05), while for the organics toxicities tests, the cell death rate was similar to the bioluminescence inhibition rate. These results indicated that organics acute toxicities to V. fisch­eri could reflect the death of cell, but metals acute toxicities to V. fischeri may not lead to the death of cell, just represent the bioluminescence inhibition.