The 5 Toxic Exposures in the TES Associated with Presumptive Conditions
The five toxic exposures currently highlighted in the Toxic Environmental Substances (TES) framework that are associated with presumptive conditions are: Agent Orange, radiation, air pollutants, heavy metals, and industrial chemicals/byproducts.
Agent Orange Exposure
- Agent Orange, a toxic herbicide mixture contaminated with carcinogenic dioxin that was widely used during the Vietnam War, is associated with increased risk of multiple presumptive conditions 1
- Exposure to Agent Orange has been linked to significantly increased risk of chronic lymphocytic leukemia, diffuse large B-cell lymphoma, follicular lymphoma, and multiple myeloma in veterans 1
- Korean Vietnam veterans with high exposure to Agent Orange experienced higher prevalence of several chronic diseases including peripheral neuropathy, multiple nerve palsy, multiple sclerosis, and skin diseases 2
- Recent research has also found an association between Agent Orange exposure and increased risk of idiopathic pulmonary fibrosis among U.S. veterans 3
Radiation Exposure
- Ionizing radiation exposure during military service has been identified as a toxic environmental substance with long-term health effects on military personnel 4
- The establishment of exposure registries for veterans exposed to radiation has been recommended to address future health effects and provide appropriate medical surveillance 4
Air Pollutants
- Air pollutants represent one of the most studied toxic environmental exposures with established presumptive conditions 5
- Specific air pollutants linked to health conditions include particulate matter, nitrogen dioxide, ozone, and traffic-related air pollution 5
- Exposure to these pollutants has been associated with various health outcomes through mechanisms involving inflammation, oxidative stress, and metabolic pathway disruptions 5
- Multiple studies have consistently identified perturbations in metabolic pathways including glycerophospholipid metabolism, pyrimidine metabolism, and tryptophan metabolism following air pollutant exposure 5
Heavy Metals
- Heavy metals such as arsenic, lead, and uranium in water are recognized toxic environmental substances with established presumptive conditions 5
- Arsenic poisoning specifically presents with characteristic signs including gastrointestinal symptoms, skin changes, neurological manifestations, and multi-organ dysfunction 6
- The American College of Medical Toxicology recommends distinguishing between inorganic and organic arsenic exposure, as they have different toxicity profiles 6
- Exposure assessment for heavy metals often requires specialized testing and consideration of both occupational and environmental sources 5
Industrial Chemicals and Byproducts
- Industrial chemicals and byproducts, including polychlorinated biphenyls (PCBs), endocrine-disrupting chemicals, and other toxic substances, are associated with presumptive conditions 5
- Exposure to certain chemicals like benzene, halocarbons, and ketones can result in inflammatory states such as hepatitis, nephritis, scleroderma, and lupus 7
- These chemicals can produce reactive oxygen species through activation of cytochrome P4502E1 or metabolism to reactive intermediates, initiating immunotoxic effects 7
- PCBs are among the most studied industrial chemicals with established health effects 5
Assessment and Documentation Considerations
- When evaluating potential toxic exposures, a detailed occupational and environmental history is essential, including chronological summary of work activities, description of workplace, and inventory of all chemicals present 5
- For veterans with suspected toxic exposures, it's important to document whether coworkers had similar symptoms and if compensation procedures have been undertaken 5
- The establishment of exposure registries for military personnel exposed to potentially serious long-term health hazards is recommended to facilitate medical surveillance and appropriate response 4