Effects induced in non-human biota

There is an increasing interest for studying the effects of pollutants at the molecular, biochemical and genetic level. In plants, environmental adversity often leads to the increase in formation of highly reactive oxygen species (ROS) resulting in a subsequent enhancement of the antioxidative defence system. The defence systems comprise antioxidative enzymes and antioxidants. Exposition to radionuclides and heavy metals may also result in direct or indirect (oxidative stress mediated) genotoxic effects. Biota possess of DNA repair systems to counteract these genetic effects.

Single stressor studies

We are analysing the biological effects induced by bioaccumulation of uranium by beans and Arabidopsis thaliana (exposed to a U concentration range) or following gamma exposure of Arabidopsis thaliana while applying a multi-biomarkers approach focused on subtle intracellular effects (DNA damage, oxidative stress, metabolites, gene expression of stress enzymes and DNA repair genes, …) viewed as early responses for individual disturbances (reduction in growth, decrease in reproductive capacity,…).

To identify the biochemical pathways and genetic changes induced following exposure to stressors, whole genome micro array analysis will be undertaken to compare gene expression patterns under control conditions and following exposure to stressors. This research is mainly done in collaboration with the university of Hasselt, Belgium.

Multiple stressor studies

Research will continue using single stressors (U, gamma irradiation, Cd) but we also started investigating investigate multiple stressors exposures. Understanding multiple stressors is particularly challenging when their combined effect cannot be predicted based on evidence from single-stressor studies, i.e. where interactions that cause non-additive effects occur. In this context we started experiments with the test plant Arabidopsis thaliana exposed to U and gamma radiation or U and Cd. We study the combined effect of radiation (and/or radiation type), U uptake and heavy metals on the measurement endpoints described above.

Environmental protection

In a larger context, we have contributed as end-users to the EC-ERICA project (An Integrated Approach to the assessment and management of environmental risks from ionising radiation) and are contributing as end-users to the EC-PROTECT project (Evaluation of practicability and merits of different approaches to protection of the environment from ionising radiation).

We actively contribute to the IAEA-Biota workgroup. We have developed and a model to assess the exposure to non-human biota in terrestrial environments, DosSDiMEco.