Testing of biota for pollutants or chemicals is often a part of environmental assessment projects.
Some of the best known examples are testing biota of eagle, seal, and fish to assess PCB levels in the Baltic sea and artic animals to prove the long-range transport of pollutants to pristine areas.
Often the testing of biota samples are done in connection with testing of other sample types such as water and/or sediments. ALS has participated in projects where water and sediments together with biota (where applicable) has been tested for all the compounds in the Water Frame Directive. Assessing levels of contaminants in biota will give a different view compared to sediments. The levels found in biota will be the so-called bioavailable fraction of the contaminants. For some compounds, or groups of compounds, the difference is more pronounced. Dioxins will show a different pattern of congeners in biota than in sediment. This is partly due to the bioavailability but also to an extent the speed of which some congeners are excreted.
Certain contaminants travel through the different levels of the food chain and can affect human beings by bioaccumulation and biomagnification in the ecosystem. ALS offers a range of tests for this segment, and depending on the compound in question we can test terrestrial and aquatic plants and animals, animal tissue, eggs, blood and serum, as well as human blood, human serum and human milk.
Natural events and human activity can indeed affect aquatic an terrestrial environment in many ways. At ALS, aquatic and terrestrial organisms can be studied – bacteria (Vibrio fischeri), fish (Poecilia reticulata), algae (Desmodesmus subspicatus), water arthropod (Daphnia magna Straus), higher plant (Sinapis alba, lactuca sativa), terrestrial arthropod (Folsomia candida), terrestrial annelidan (Enchytraeus crypticus) to mention but a few. Ecotoxicity tests provide information on the intensity of adverse effects resulting from human influences and can produce data in the evaluation of the potential environmental impact of substances discharged into water or spread on land.