TO OUR KNOWLEDGE, THE ADVERSE EFFECTS OF BURN PIT EXPOSURE HAVE NOT BEEN INVESTIGATED AT THE SUBCELLULAR LEVEL BUT COULD BE THE BASIS FOR SERIOUS PROBLEMS. THE IDEA THAT TOXIC EXPOSURE CAUSES BIOCHEMICAL AND EPIGENETIC CHANGES THAT LEAD TO SERIOUS CHRONIC HEALTH PROBLEMS IS SUPPORTED BY THE LITERATURE AND OUR PRELIMINARY DATA. WE COMPARED THE BLOOD FROM FIREFIGHTERS TO CONTROLS AND FOUND REGIONS WITH DIFFERENTIAL DNA METHYLATION IN GENES THAT REGULATE REPRODUCTIVE FUNCTION. SUCH EFFECTS WERE EVIDENT IN ABNORMAL REPRODUCTIVE HORMONE LEVELS FOR THE FIREFIGHTERS. SIMILARLY, WE PROPOSE THAT PARTICIPANTS OF THE BURN PIT REGISTRY POSSESS LASTING EPIGENETIC AND HEALTH CONSEQUENCES CAUSED BY THE EXPOSURE THAT REQUIRES INVESTIGATION.