"There are either rogue manufacturers or poorly tested products getting into the market."

A warning for parents about a popular children's toy.

UK researchers found that some fake slime products contain toxic levels of chemicals that can cause serious illness and infertility later in life.

Researchers tested eleven of the most popular fake slime products on the market and found that eight of them had dangerous levels of boron, an ingredient commonly found in pesticides and household cleaners.

Roland Earl is the Director General of the British Toy and Hobby Association. He says,"I think The Which? report is very important and timely. Obviously, there are still out there some great slimes, but the report clearly shows that there are either rogue manufacturers or poorly tested products getting into the market."

Earl says if you are not bothered with that and you are producing counterfeits that you not only get a competitive advantage against people who test it but also expose consumers to considerable danger.

All of the slime products that failed were bought online from Amazon.

The company has since removed them from sale.