(CNN)Parents may want to take a second look at their children's school supplies this season.
The results of lab tests detailed in a report released Tuesday found traces of asbestos, lead and other dangerous chemicals in a number of popular school supplies.
The US Public Interest Research Group Education Fund tested dozens of typical classroom materials for toxins. While most were nontoxic, some crayons, markers and binders received a failing grade.
Here are some of the products that tested positive for toxic substances:
Playskool crayons (36 count)
This box set, purchased at Dollar Tree, has traces of asbestos, the report found. The chemical can appear in the talc that is used in crayon manufacturing, according to the report.
If ingested or inhaled, asbestos can cause severe damage to a person's health, including lung cancer and mesothelioma.