SAN FRANCISCO (KGO) -- Just in time for back to school shopping, a consumer group has come forward with a warning. Some of those wholesome products may contain dangerous chemicals. And it's telling you which ones.
"Just because a product is on store shelves, it doesn't mean it's safe for children,'' said Laura Deehan, public health specialist with the California Public Interest Research Group, known as CalPIRG.
The organization tested dozens of school supplies and found that most of them had no sign of any toxic ingredients. However, CalPIRG and its national umbrella organization, US-PIRG, found some did contain potentially dangerous chemicals.
Among the most surprising, CalPIRG said it found asbestos in Playskool brand crayons.
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"We're calling on Playskool to recall the crayons which we found were containing asbestos and to notify parents who may have unwittingly purchased these toxic ingredients,'' Deehan said.
Asbestos is linked to cancer -- and while the Consumer Product Safety Commission recommended eliminating it from children's products, it is not expressly banned from use in children's products.
"Today, it's actually legal to include asbestos in children's crayons, even though breathing or ingesting crayons can be highly toxic, especially to children with their growing bodies,'' Deehan said.
Playskool's parent company, Hasbro, said it was investigating the claim. The manufacturer, Leap Year Publishing, challenged the US-PIRG and CalPIRG test results. It said:
"There is nothing more important to Leap Year Publishing than the safety of our products in the hands of children. All of our products, including the Playskool-branded green crayon mentioned by PIRG, are thoroughly tested by labs to meet or exceed all CPSC and federal standards for safety. We are currently re-verifying that they are safe and free of any asbestos, as well as requesting a review of PIRG's testing methods."
CalPIRG said it tested the green crayon in 36-pack boxes of Playskool crayons, a color chosen randomly for examination. It also tested other brands, including Crayola and Rose Art, and said that tests came up negative for asbestos and other toxic chemicals.
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Asbestos is a naturally occurring fiber within talc, which sometimes has been used to make crayons. It's usually only dangerous if airborne or ingested -- but Deehan says some kids are known to chew on them.
"I've had parents tell me their kids have ingested crayons at different points, or while you're coloring a lot you could be breathing in asbestos fibers. Even if it's a small amount over a long period of time, I don't know why we would take that risk when we don't need to."
Another finding: CalPIRG said it found benzene -- a known carcinogen -- in magnetic dry erase markers made by "the Board Dude.'' CalPIRG says it's legal to use benzene, but also unnecessary.
"Parents should know what is in the products they buy for kids and make their own choices,'' she said. "Parents should be able to shop safe, knowing the products they buy for children are safe and free of toxic ingredients."
The Board Dudes' parent company, Mattel, said it takes safety seriously and will investigate the claims. A company statement said:
"The safety of children is and always has been Mattel's number one priority. The Board Dudes magnetic dry erase markers, as identified by the Campaign for Toxic-Free Products with U.S. PIRG, contain substance levels that fall within the permissible limits. We take these reports seriously and are conducting a thorough review into the claims. We want to reassure families that we aggressively test all materials to ensure they are within compliance of the industry standard."
CalPIRG says federal limits on toxic chemicals in "children's products" don't necessarily extend to notebooks and pens. That's because anyone of any age may use them.
"Unfortunately, school supplies are often not considered children's products even if they are in the back-to-school aisle marketed to children,'' Deehan said. "They're school supplies anyone can use. "
The group also found phthalates in a three-ring binder sold by Dollar Tree. Phthalates also are legal, though also linked to cancer and possible hormone damage.
In a statement, Dollar Tree said: "The safety of our customers and associates is our top priority. Our Company utilizes a very stringent and independent testing program to ensure our supplier products meet or exceed all safety and legal standards. We are aware of the report and have since re-verified that each of the listed products successfully passed inspection and testing."
CalPIRG also notes the CPSC has recalled water bottles coated with paint containing unsafe levels of lead.
Federal rules do restrict lead content in consumer products. Though one recall took effect in 2016 and another just last April, CalPIRG says parents might have them in their homes unaware of the lead problem.
"We want to make sure that parents should check their homes and make sure they are not letting their children use these bottles,'' she said.
The recall affects the Base Brands Reduce Hudro Pro "Furry Friends" water bottle sold at Costco and Amazon, recalled on April 19, 2018 and the GSI Outdoors Kids' Insulated water bottles sold at L.L. Bean, recalled in July 2016.
Parents also can look for products with a label by the Art and Creative Materials Institute. The label means the products are tested regularly by the Institute, and came up toxin-free.
"If you look for the AP label you can rest assured they'll be safe."
You can also read the CalPIRG "Safer School Supplies Shopping Guide,'' which lists all the products the group tested. It will show you which ones it says contained toxic chemicals, and which did not.
Click here for a look at more stories by Michael Finney and 7 On Your Side.
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Group reports toxic chemicals in some back-to-school supplies
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