Onions and garlic can absorb toxic leftovers from factories. | varbenov/Shutterstock

Sign up for the Newsletter Sign Up

Sign up for our email newsletter for the latest science news

Onions and garlic can turn around a bland dish, but Indian biotechnologists have found another use for these roots: filtering heavy metals from toxic brews.

Scientists looking for new cleaning compounds mixed onion and garlic leftovers from canning factories with various industrial wastes.

The two Allium roots absorbed about 70 percent of toxins — including arsenic, cadmium, mercury and lead — and they could be reused to clean again.

[This article originally appeared in print as "A Recipe for Toxic Cleanup."]