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Mercury in fish - how does the environment effect the levels?

Published: 19 September 2017

In a new thesis has Pianpian Wu studied methyl mercury in the food web in Swedish lakes and water courses She found that clearcuts increased the concentrations of mercury in fish, but the variations between the studied lakes were large.

Mercury is dangerous for both animal s humans. In her thesis has Pianpian Wu studied different aspects on how mercy is made biologically available in the environment and how mercury is accumulated in the food web.

Measurements in lakes showed that the mercury levels increased in fish after clearcutting in the catchment of the lake. There were however large variations between the studied lakes.

New established beaver ponds were also studied in the thesis work. Increased concentrations of methyl mercury were discovered together with changes in the carbon concentrations in the beaver pond sediments.

Apart from measurements Pianpian Wu also performed a literature review with a meta analysis. It showed that accumulation of methyl mercury in lake ecosystems is related to the relationship between the concentration of methyl mercury in the water and the amount of seston or zooplankton in the water. The bioaccumulation of methyl mercury was in a laboratory study also related to different fatty acids to differentiate between different food sources in the food web.


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