Fine particle exhaust from the combustion of wood has become a relevant issue in risk assessment for human health because there is an increased use of renewable energy. Our project intends to establish in vitro methods that provide a holistic risk assessment of fine particles originating from the furnaces of wood. As a particle feeder C. elegans is a suitable model organism to examine the effect of ingested particles. Expression profiling is conducted with C. elegans to identify and distinguish the modes of action of the particles. Former studies by other authors reveal a high risk for mammals exposed to atmospheric dusts to present with respiratory diseases e.g. asthma, COPD and lung cancer. The latter is ascribed to oxi dative stress and ensuing reactive oxygen species within the alveolar tissue. Although the oxidative stress mediated pattern of changes in gene expression in C. elegans is well characterised, it does not allow clear distinction of changes subsequent to pure oxidative stressors from other stresses. A first step is to characterize signal-transduction factors possibly unanimously involved in an oxidative stress response. This includes the transcription factor
skn-1. Skn-1 displays a relation to human Nrf2 transcription factor and in embryonic development is required for intestinal development. Its nuclear translocation is regulated by
p38 MAPK. In the nucleus
skn-1 initiates the transcription of many genes responsible for the defence against oxidative stress and for phase II detoxification. GFP fusion proteins may allow clarification of the role of key-factors in the oxidative stress. Furthermore we will concentrate on other modes of action induced by wood combustion particles e.g. neuro- and cytotoxity, inflammation, endocrine disruption or mutagenicity. In combination with other test systems encompassing cell lines and bacteria we aim to achieve a holistic risk assessment for particles originating from the combustion of wood.