Toxicity of sediments and their leachates in samples from portman bay (SE, SPAIN)

Abstract

Increasing evidence suggests that the use of a single bioassay will never provide a full picture of the quality of the environment. Only a test battery composed of bioassays of different animal and plant species from different trophic levels will reduce uncertainty, allowing an accurate assessment of the quality of the environment. In the present study, a multitrophic assessment approach was applied to characterize the toxicity of sediments collected from Portman Bay (SE Spain), polluted by mining activities. Elutriate toxicity tests (Vibrio fischen) and whole sediment toxicity tests (plant species Sorghum saccharatum, Lepidium sativum and Sinapis alba and the crustacean Heterocypris incongruens) were evaluated and results suggested that all the leachate samples were non-toxic for Vibrio fischeri bioassay. However, sediments were toxic for plants and ostracods, showing the highest toxicity in Sl and S6. Correlation analysis results showed that toxicity was positively correlated with total Pb and Zn contents, and with soluble As.