The crayons which are made in China by a company known as Amscan, as well as two science kits for children which have also been found to contain asbestos, are available in Australia from a number of online retailers and party suppliers. Fairfax Media was unable to find any products sold over the counter in retail stores.

The shock discovery of asbestos fibres was made in the US, after tests were conducted at the Scientific Analytical Institute in Greensboro, North Carolina, for a report commissioned by the environmental non-profit Environmental Working Group Action Fund. The report said it is unclear how the asbestos got into the crayons and crime kits but it may have come from a contaminant of talc used as a binding agent in the crayons and in powder in the crime-scene fingerprint kits.

Previous tests in the US have found asbestos in crayons imported from China. In 2000 asbestos was found in crayons and in 2007 asbestos was also found in crime kits.

The National Toxics Network (NTN) has attempted unsuccessfully to alert the Australian Competition and Consumer Commission, the body responsible for the safety of products in Australia to the potential problems.

Dr Mariann Lloyd-Smith, of the NTN, said: "We are deeply concerned that similar toys and crayons imported into Australia from China may also be contaminated with asbestos.

"We request that the ACCC investigate this issue as a matter of priority."

Dr Lloyd-Smith said the group had rung the ACCC.

"We sent the … electronic letter via the contact on their website and received this response: 'We are currently experiencing a backlog and our response time may exceed 15 days'."

A spokeswoman for the ACCC said there is currently a delay in responding to contacts  "within usual timeframes as we transition to a new case management system".

"The ACCC is aware of the report and taking steps to determine whether and to what extent these products are in the Australian market, and to assess what steps need to be taken to minimise any risks to consumers."

The federal Department of Health has issued warnings about asbestos saying "although there is no absolutely safe level of exposure to asbestos fibres, occasional exposure to low levels of fibres poses only a low risk to your health".

However, international experts have warned that exposure for children can be more serious.

The US Centres for Disease Control and Prevention has said that exposure to asbestos as a child means there's more time for an asbestos-related illness to develop later in life.

The US Consumer Product Safety Commission said that the risk to children from asbestos in crayons is "extremely low" because asbestos fibres are embedded in the crayon wax. But the fingerprint powder could easily be inhaled.

The brands are listed as Amscan Crayons, Disney Mickey Mouse Clubhouse crayons, Nickelodeon Teenage Mutant Ninja Turtle Crayons, Saban's Power Rangers Super Megaforce crayons, EduScience Deluxe Forensics Lab Kit (black fingerprint powder), and Inside Intelligence Secret Spy kit (white fingerprint powder).

The EduScience Deluxe Forensics Lab Kit (black fingerprint powder) is available online through well-known toy retail websites.