Nearly half of the 5 million veterans that have been screened by the Department of Veterans Affairs (VA) under a new law have reported at least one possible exposure to toxic substances during their military service.

Announcing the 5 million screening milestone, the VA revealed that 2.1 million veterans — or 43 percent of those screened — were potentially exposed to such substances during their service.

A variety of toxic exposures can come up in these screenings, but the most common were exposures to burn pits and Agent Orange.

Exposure to burn pits and other airborne hazards that can be encountered during military service can cause a variety of cancers including those affecting the brain, neck, kidneys and pancreas.