(WCMH) – Tests recently conducted on crayons sold at Dollar Tree stores revealed trace amounts of asbestos. 

The U.S. Public Interest Research Group Education Fund’s campaign for toxic-free products released the results of the crayon test on Tuesday, along with the results of tests from many other back to school products.

Of the six brands of crayons tested, asbestos was found in Playskool crayons sold at Dollar Tree.

The lab tested two samples of the green crayon.

Asbestos is a known carcinogen and can lead to serious health conditions, including lung cancer and mesothelioma.

Other results include:

  • Lead in recently-recalled children’s water bottles (Base Brands children’s Reduce Hydro Pro Furry Friends water bottle, once sold by Costco, and GSI Outdoors children’s water bottle, once sold by L.L. Bean). The Consumer Product Safety Commission recalled both of these items because they contained high levels of lead. Lead can cause severe developmental and behavioral problems.
  • Phthalates in Jot brand blue 3-ring binder. The levels of phthalates in the binder are considered unsafe for children by the Consumer Product Safety Commission. High levels of phthalates can lead to birth defects, hyperactivity and reproductive problems.
  • Benzene in Board Dudes brand markers. Benzene is a known carcinogen linked to leukemia and disruptions in sexual reproduction and liver, kidney and immune system function.

“Based on our testing, we know that most manufacturers make safe school supplies. We’re calling on the makers of unsafe products to get rid of toxic chemicals and protect American schoolchildren,” said Kara Cook-Schultz, U.S. PIRG Education Fund Toxics Director.

A spokesperson for Playskool’s parent company, Hasbro, told the Chicago Tribune that it is conducting an investigation into the claims. The manufacturer of the crayons, Leap Year Publishing, also told the Tribune it is reviewing the tests.

>> Click here to read PIRG’s full safe-shopping guide.