Abstract # 1769 Exposure during fire-overhaul period demonstrates an increase in disease risk and immune dysregulation for first responders with impact being reduced using a transitional technique

Exposure during firefighting activities to combustion products (including carcinogens and asphyxiants) has been shown to increase immediate and long-term health risks of first responders. Therefore, we investigated the role of smoke inhalation on increasing disease risk and immune dysregulation by placing mice in the overhaul period of a live-fire scenario for 15 min. During the attack, we used two separate firefighting techniques, interior vs transitional. Lung tissue was harvested 2 hours post-exposure and RNA extracted for RNA-seq analysis. There was a 10.3% reduction in the temperature between interior and transitional techniques amongst live-fire scenarios. Correspondingly, there was greater differential gene expression with the conventional interior technique when compared to the transitional attack (2666 vs 60 genes, respectively). Within the interior technique, gene pathways that were over-represented included rap1 signaling, asthma, B-cell receptor signaling, proteoglycans in cancer, and non-small cell lung cancer. Interior technique showed upregulation of carcinogenic proteins such as Rorc and capn11 with downregulation of tumor inhibitors such as S100a8 and S100a9 whereas transitional technique did not show similar gene expression changes. Consequently, we conclude that first responders face an increased risk of disease during overhaul as demonstrated by over-representation of cancer-related pathways and changes in immune regulation. Importantly, this data shows strong evidence for first responders using techniques that rapidly apply water to mitigate their risk of cancer and immune related diseases.