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70% of Slime Toys Detected with Boron Exceeding Upper Migration Limit with the Worst Sample Exceeding the Limit by over 12 Times Beware of Microorganisms and Preservatives Harming Children's Health

  • 2019.08.15

Slime and putty toys have become popular amongst primary and secondary students in recent years and some products even claim to be able to relieve pressure. The Consumer Council conducted a test on 20 models of slime and putty toys to find that these toys may pose safety and hygienic risks. The migration of boron of 70% of the slime models exceeded the European Standard's recommended upper limit with the worst model exceeding more than 12 times. Moreover, 2 models were detected with total microbial counts exceeding the EU Recommendation's limit by 23,999 times and 119 times respectively. The content of MIT and/or CMIT and CMIT/MIT mixture of 5 models exceeded the standard's recommended limit. In addition, it is worrying to note that all models did not provide any information of their expiry date and 5 models failed to provide adequate users' warnings.

The Council is deeply concerned about the safety and hygiene of such toys. Children ingesting or being exposed to excessive amount of boron in long term are at risk of harming their reproductive system and children coming into contact with toys containing excessive microorganisms or allergy-causing preservatives may also increase the chance of skin infection or skin allergic reactions. The Council called for the relevant authority to step up enforcement measures, while toy manufacturers are urged to strengthen quality inspection to safeguard consumers’ health.

The test included 20 models of the pre-made slime and putty, including 17 slime and 3 putty models, and focused on the migration of 19 certain elements such as boron, lead, tin, aluminium, strontium and zinc; total microbial count; phthalates content; allergy-causing preservatives CMIT and MIT content and the amount of free formaldehyde; preservative efficacy; and product labelling. 

The test on migration of certain elements was conducted with reference to the more stringent European Toy Standard EN71-3. The results indicated all models to contain boron, ranging in migration from 26ppm to 3,970ppm. The boron migration of 12 slime models was found to exceed the recommended upper limit of the standard (300ppm), with the worst model exceeding the limit by more than 12 times.

Boron compound is always used in the raw materials for producing slime and putty toys to make them more elastic and stretchable. When children, after playing with toys with high migration of boron, touch the mouth or food without first washing their hands thoroughly, they are at risk of ingesting the chemical. Ingestion of boron, in medium to high dosage, may induce nausea and vomiting and, in the long term, has an adverse effect on the fertility. Manufacturers are urged to limit the boron content in toy products to safeguard the safety of children.

Concerning product hygiene, 2 slime models were detected with total aerobic microbial count of 24,000,000CFU/g and 120,000CFU/g, both exceeding the limit of NB Toys Recommendations under the EU Toy Safety Directive (1,000CFU/g or CFU/ml), by 23,999 times and 119 times respectively. The same 2 models were also found to contain Enterobacteriaceae, exceeding the recommended limit of 100CFU/g. It should be noted that microorganisms grow easily in slime toys. Children’s hands coming into contact with their eyes or open wounds, or eating without first washing the hands thoroughly after playing the products with excessive microorganisms, may induce bacterial infection.

Slime toys are vulnerable to contamination by the microbial on hands and in the air. The efficacy of preservatives in slime toys was assessed with reference to the European Pharmacopoeia. The results showed that 3 of the models were unable to pass all the test items, indicating that the preservatives in these models could not effectively inhibit the growth of some microorganisms. Parents should pay attention to the hygienic condition of these products after opening the package and should discard them when their quality is found deteriorated.

Preservatives may be added in slime or putty toys to reduce chances of microbial contamination. Some of the preservatives such as MIT, CMIT in high concentration may cause skin allergy. The test found the presence of MIT and/or CMIT in 12 models of which 5 were detected with MIT and/or CMIT and CMIT/MIT mixture content exceeding the recommended upper limit of the European Toy Safety Standard.

Moreover, 5 models were found to detected with free formaldehyde with 2 of them exceeding the recommended upper limit of the European Toy Safety Standard (500 ppm). Dermal contact with formaldehyde may produce temporary skin irritation, but for people who is sensitive to formaldehyde, prolonged skin contact may lead to adverse skin reactions, including allergic contact dermatitis, itchiness and rash.

2 slime models were also found to contain dibutyl phthalate (DBP) with content reaching 0.96% and 1.12%, which do not comply with the total content requirement of 3 particular phthalates of not exceeding 0.1% under the EU REACH and Hong Kong Toy Safety Regulations. Although DBP has low skin and eye irritation, parents should be aware that cumulative exposures to DBP and other phthalates may pose potential risk to children’s health in long term.

Improvements are also required for product labelling as the Council found 5 models had failed to provide sufficient information in labelling, such as the warning - “avoid contact with open wound”. Also, more than half of the models did not provide warning to remind the users to wash hands after use. Besides, 4 models were found in non-compliance with the local regulation to list out the information of the toy manufacturers, importers or suppliers as well as their contact addresses in Hong Kong. Despite some models were marked with the production batch number or date of production, none of them provided indication of best before date and validity period for use. In the absence of such information at the time of purchase, consumers have no way of finding out the product expiry date, and are at risk of buying expired or microbial contaminated products. 

Parents are advised not to let their children make “home-made” slime. The common ingredients in slime, namely, borax/boric acid and its solvents, could cause skin burn. Borax/boric acid in powder form can also cause irritation of eyes and respiratory tract. 

Boron compound could contaminate environment, including water, air and soil. In order to reduce pollution and support sustainable consumption, consumers should avoid purchasing such products. For consumers who choose to play with slime or putty toys, they should take heed of the following safety tips:

- Some slime or putty toys may look and smell like beverages or desserts. Parents or adults should accompany children when playing with such toys to prevent accidental ingestion by young children or pets;

- Clean hands thoroughly before and after playing slime or putty toys, if itchiness or rash occurs, stop playing them immediately;

- Avoid slime or putty toys getting into contact with the eyes, mouth, nose and open wounds, and do not eat or drink at the same time while playing the toys;

- Never leave slime or putty toys on the bed to avoid prolonged contact while sleeping;

- Ensure proper storage in the original packaging or in sealed boxes to avoid environmental contamination. If the toys covered in dust or hairs, dispose them immediately.

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