Burn pits, radiation, toxin, biological hazards...everything. Everything a veteran might have been exposed to can now be denied by the VA.
That's right. VA did this by redefining the word exposure to their own liking. Since 2012, VA's redefinition of exposure is, "Exposure = contamination field + bioavailability."
This means VA won't acknowledge an exposure event unless and until the veteran can prove some biological harm specifically from the exposure. Unless VA or Congress establishes presumptive service connection, as was done with the "boots on the ground" Vietnam veterans, VA can now block any exposure claim unless the impact of the exposure is so immediate as to be indisputable.
The VA definition is unique to science. In fact, challenged by the rest of science. The Director, National Toxicology Program reports, "In all my years as a toxicologist, I have never heard the term bioavailability as part of the exposure field." In their determination to prevent claims, VA Post Deployment Health invented this just for us veterans!
VA won't concede your exposure if you walk into a tent of Ebola patients...unless you develop Ebola and can prove it was from that tent. But in fact, you've been exposed to Ebola, bioavailability or not, and VA won't treat you unless and until you develop Ebola as proof of your exposure.
But you can't prove it and the VA will deny your claim. That's their purpose of the redefinition of exposure...to prevent exposure claims from veterans who have been exposed.
Makes sense from their perspective: VA saves serious money by not treating disabled veterans ill from their exposures. Makes no sense from a veteran's perspective, finding VA hospital doors locked when we're ill.
The list is long...occupational hazards such as asbestos and lead, inoculations, dirty water, radio frequencies, smoke, toxins, chem warfare, dust, bugs...everything for which a veteran might actually experience exposure can be denied with VA's handi-dandi redefinition of exposure, the magic of defining away your disability claim!
Look at the University of Washington exposure graph below, which shows outcome (bioavailability) as an event after exposure. Do you get it? VA now says exposure requires outcome to be exposure. If you can't prove the outcome you haven't been exposed...for example, if you can't prove your prostate cancer came from contact with Agent Orange, VA's definition says you were never exposed.
Using that definition VA can deny service connection for virtually every exposure. Indeed, using it, Post Deployment Health's Acting Chief Consultant informed The C-123 Veterans Association last year that no veterans were exposed to Agent Orange in Vietnam (other than perhaps some Ranch Hand crews.)