Universiteit Leiden

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Development of a consistent methodology for assessment of the combined effects of metal-based chemicals to lettuce (Lactuca sativa L.)

Hoe kan de methode om de gecombineerde effecten van metaal-gebaseerde chemische stoffetn te bepalen worden verbeterd?

Looptijd 2011  -  2015
Financiering The project is funded by the China Scholarship Council.


Short abstract

With the continuously excessive human activities, organisms are always exposed to chemical mixtures instead of single compounds. How to accurately estimate the combined effects of mixtures to ecosystems has become a critical issue. This PhD project aims at quantifying mixture toxicity of metals with different sizes to lettuce ( Lactuca sativa L.) and the impacts of interacting processes on their actual effects. The expected results are to help understand the mechanisms that metal-based chemicals interact with organisms and create suitable criteria in controlling elevated concentrations of these chemicals to protect biodiversity of aquatic and terrestrial ecosystems.

Project description

Elevated concentrations of metals in different sizes has diminished the biodiversity of aquatic and terrestrial ecosystems and endangered the health of human beings. Plants play an important role in the biogeochemical cycling of the elements and can be efficient biomarkers for metal-related chemical stresses. However, ecological effects assessment for metal mixtures sizes of which ranging down to the nanoscale is still in its infancy.

Multiple layers of interacting processes increase the difficulty of accurate estimation of bioavailability and toxicity of metals. In addition, simple correlations cannot satisfy the specific physiological processes in higher plants such as metal-specific selectivity. How to choose a suitable approach in mixture toxicity modelling across various exposure situations and across different combinations of metal pollutants in different sizes is to be assessed.

CML is a strategic multidisciplinary department in relation to the sustainable management of natural resources, environmental quality and biodiversity. This supports our project in addressing the relations between human activities and the natural environment.