The U-S PIRG Education Fund tested 27 back-to-school supplies. Four tested positive for dangerous chemicals.

They found:

- asbestos in Playskool crayons from Dollar Tree

- phthalates in a 3-ring binder from Dollar Tree

- BTEX, a group of four harmful chemicals in Expo dry erase markers from Amazon

They also found lead in two water bottle brands: Base Brands Reduce Hydro Pro Furry Friends water bottles and GSI Outdoors Kids' insulated water bottles.

We know the damage exposure to these chemicals can cause. Asbestos has been linked to lung cancer.

Phthalates can mess with your kid's hormone levels and cause birth defects. And we all know too much lead exposure can cause organ damage and even death.

Oddly enough, the report says it is legal to have asbestos in crayons and phthalates in some school supplies, although scientists point out it's unnecessary to expose children to these toxins.

Since it is legal to sell products containing toxic substances, here's what you need to do to help keep your kids safe.

First, the report says to look for a label on your kids' school supplies. This is the Art and Creative Materials Institute "AP" label. It stands for "approved product" and means the product is not toxic.

Second, if there is no AP label, look for the manufacturer's "children's product certificate" on the product. That means it's been tested by a third party and passed the Consumer Product Safety Commision standards.

And if neither of those labels is on the product, contact the manufacturers and ask if they are AP certified or meeting the requirements for children's product certificate.

For more information, read this article.

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