Grand Canyon National Park staff members have had to remove contaminated soil from the park recently after campers have been using bleach and ammonia products to repel ants.

The park posted on Facebook to urge campers to refrain from using such products saying the “chemicals kill plants, bio-crusts and animals.”

Park staff members say they have had to “remove contaminated soil and dispose of it, much like an oil spill.”

According to the post, campers spread bleach and ammonia products around their tents to prevent ants from getting in.

But the Grand Canyon wildlife biologists say there are other ways to keep ants away, such as storing food and strongly scented products in sealed containers.