A comparison between toxicity tests using single species and a microbial process.

P van Beelen; A K Fleuren-Kemilä

doi:10.1016/s0045-6535(98)00559-1

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A comparison between toxicity tests using single species and a microbial process.

P van Beelen·A K Fleuren-Kemilä

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Abstract

In this study the sensitivity of the acetate mineralization process performed by five strains of microorganisms in soil for the toxicants Zn2+ or PCP was calculated from the sensitivity of the contributing species. The species used were a fungus (Aspergillus niger CBS 121.49), an actinomycete (Streptomyces lividans 66), two Gram-negative Pseudomonas putida strains (MT-2 and DSM 50026) and a Gram-positive strain Rhodococcus erythropolis A177. For zinc the EC10 of the process performed by the five strains together was 77 mg/kg whereas for pentachlorophenol it was 2 mg/kg. The EC10 of the process was compared with the EC50 of the most sensitive species contributing to the process. P. putida MT2 was the most zinc sensitive strain (EC50 = 22 mg Zn/kg) and A. niger was the most sensitive strain for pentachlorophenol (EC50 = 1.4 mg/kg). This shows that a 10% inhibition of a process can be accompanied by a more than 50% inhibition of the most sensitive species.

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Acetates Aspergillus niger Environmental Pollutants Pentachlorophenol Pseudomonas Sensitivity and Specificity Soil Microbiology Streptomyces Toxicity Tests Zinc Isotopes Comparative Study Journal Article

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P van Beelen, A K Fleuren-Kemilä. 1999. A comparison between toxicity tests using single species and a microbial process.. https://doi.org/10.1016/s0045-6535(98)00559-1

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