Conclusions of the ICT X SATELLITE MEETING: Indoor Mold –A New Challenge for Toxicologists (10th July, 2004 Kuopio).
The symposium of “Indoor Mold -A New Challenge for Toxicologists” was held in Kuopio, Finland, 10th July, 2004. The event was a satellite symposium of the 10th International Congress of Toxicology, Tampere, 11-15 July.
The exposure to biological contaminants in indoor air of damp and moldy indoor environments is a challenge for toxicological research and risk assessment. The intent of this Satellite meeting was to present recent scientific results on exposure and health effects of microbes and their toxins in indoor air, and to discuss the implementation of current knowledge.
The specific aims were:
• To bring forth the clinical aspects of exposure to indoor mold both in home and in workplace
• To share the recent scientific advances in experimental toxicology
The symposium had over 30 participants from different countries and different areas of research. The symposium ended up with a conclusion that dampness control of buildings is essential for the prevention of health effects. However, due to the many existing problems, the need for the toxicological documentation of the harmful agents and their effects was recognized. As the summary of the Symposium, the following conclusions, challenges and research needs for toxicology were presented.
Conclusions
• Dampness and mold in indoor environments are associated with many diverse health effects, some of which are well documented in epidemiological studies, and some of which have been reported as clinical observations
• Based on current evidence, it can be concluded that there is a biologically plausible connection between the growth and occurrence of toxigenic molds in indoor environments and health effects of the occupants. However, many aspects of exposure and pathophysiological mechanisms are still to be revealed
• No single exposing agent appears to be the causative factor for the health effects
• Moist building materials may be favourable habitats for many potentially toxin-producing fungi and bacteria
• Toxins occur both in the mycelium and in spores. The release of spores and mycelial fragments can be a source of inhalation and dermal exposure to toxins
• Other microbial products and components such as peptides, enzymes, ?-D-glucans and LPS may have significant biological effects
• Health endpoints are probably results from exposure to many exposing agents, which also have interactions
• More toxicological research is needed to reveal the causal connections between exposure and health effects of moldy indoor environments
Challenges and research needs for toxicology
• Challenges for toxicological risk assessment
-Wide variety of health end points and wide variety of mechanisms
-Importance of building materials on microbe’s toxicological behaviour
-Interactions of different species in microbial growth and/or in exposure situations
-Solving the key question of ”causative agent”
• Open questions
-What model system would give the best measure for neurotoxicity or for pulmonary toxicity?
-Which organs are typically affected?
-What explains gender, genetic, age and other host factor differences?
• Research needs on microbes and their toxins
-Development of biomarkers
-Toxicity assessment of airborne material
-Assessment of neurocognitive outcome
-Case-control studies, intervention studies
-Establishment of NOAEL in acute animal models
-Long term, low-dose exposures in animal models
-In vivo studies on effects of fungal particles and toxins especially in proximal respiratory tract
