Biotechnology

Early Murine Immune Responses from Endotracheal Exposures to Biotechnology-Related Bacillus Strains

The Bacillus bacteria are a group that is used in biotechnology applications, but also cause problems such as food poisoning and other infections.  The bacteria can form dormant spores, which are resistant to environmental conditions and can germinate and replicate at a rapid rate.  As Health Canada is responsible for the health risk assessment of biotechnology microorganisms, this study was aimed at developing new scientific tools and contributing knowledge to inform risk assessment.  This study examined different strains of Bacillus bacteria, as well as commercial products containing larger numbers of spores, for their capacity to cause immune system effects in mice following inhalation.  The dormant spores of all the strains examined caused very few effects even one week after exposure, but the replicating bacteria caused mice to show strong immune and systemic effects just two hours after exposure. The Bacillus spores were found to produce few effects compared to the effects of replicating Bacillus bacteria.  This early screening approach was successful in distinguishing the adverse effects of the different Bacillus strains, and may be useful in assessing the relative hazard potential of other biotechnology-related bacteria to inform risk assessment and support safe handling practices.  This study was published in Toxicological and Environmental Chemistry (2011 Feb), 93(2):314-331.