SAN FRANCISCO (KCBS)— Harbor seals are helping with human health research. According to Dr. Jennifer Scarlett with the San Francisco SPCA, because they live their life on the shore or very close to the shore, researchers view them as samplers of the environment.

The grey-spotted seals that are about five-feet long, have a population of about 35,000 along the California coast live close to humans and eat many of the same fish.

“Basically if Harbor seals are coming into contact with anything toxic so are Californians,” Scarlett said.

The Marine Mammal Center has been able to create disease maps because the toxins are so regional. In San Francisco water, samples showed a high incidence of flame-retardant chemicals and other industrial toxins. In Monterey, Scarlett said researchers are finding pesticides.

The purpose of the disease maps are primarily used to help marine mammals, but they can alleviate the disease conditions in the long-term by helping areas with persistently high-levels of toxins.