Risks include exposure to swimming pools, salt water aquariums, or ocean fish.

Ultimately it may determine whether we can keep on eating ocean fish, the last truly wild food on earth.

Indeed, ocean fish are the last wild food on earth we eat with any regularity.

They are ocean fish which regularly stray into coastal waters around the world.

They traded for ocean fish with the coastal Tongva on a daily basis.

But some ocean fish are contaminated with parasites that can cause infection in humans.

Some ocean fish, like salmon and halibut, can be contaminated with parasites.

They help determine where ocean fish can thrive and where they cannot.

A lot fresher than any ocean fish available here.

They traded for ocean fish with the coastal Tongva.