Toy Slime

Date: August 2018, Version 1

What is it?

Toy ‘slime’ is generally bright in colour and sold in a plastic pot. In July 2018 the UK consumer group ‘Which?’ found that eight out of 11 slime toys tested contained higher levels of a chemical called boron than is allowed in the EU. The boron found in slime toys comes from a substance called borax, which is added to toy slime to maintain its texture. Borax is also commonly found in detergents, enamel glazes, insecticides, and is used as a preservative in some contact lens solutions.

The information in this document is written for pregnant women who have handled or swallowed the brands of toy slime for which safety concerns have been raised. Details of these specific slime toys  can be found on the ‘Which?’ website (clicking here should take you directly to the report).

Will contact with toy slime in pregnancy harm my baby?

In general, products which are not made by an approved manufacturer should be avoided as they may not have gone through the recommended safety and quality control checks and could therefore contain harmful substances. Particular care should be taken with products sold via the internet or from market stalls.

Handling toy slime: Borax in toy slime cannot easily pass through unbroken skin. The amount entering the mother’s bloodstream and potentially reaching a baby in the womb is therefore expected to be very low and unlikely to cause problems. Although women are advised, as a precaution, to avoid handling slime with high levels of boron if pregnant, no treatment or testing is needed if handling has already occurred. 

Swallowing toy slime: Swallowing toy slime may result in borax poisoning (toxicity), depending on how much is swallowed. Symptoms of borax toxicity include diarrhoea, vomiting, kidney problems, skin inflammation and blistering, coma and convulsions (fits). If you experience any of these symptoms after swallowing toy slime, seek medical help immediately as early treatment can limit or prevent serious problems associated with borax poisoning.

One small study in humans showed that women who were exposed to boron in drinking water did not have a higher chance of having a miscarriage, stillbirth, early delivery, a baby with a birth defect, or a low birth weight baby compared to unexposed women. However, animal studies have not been able to rule out that ingestion of a chemical similar to borax may be linked to birth defects in the baby.

Will my baby need extra monitoring during pregnancy?

As part of their routine antenatal care most women will be offered a scan at around 20 weeks of pregnancy to look for birth defects and to check the baby’s growth.

Handling toy slime during pregnancy is unlikely to cause any problems that would require extra monitoring of your baby. There is, however, not very much information on boron poisoning in pregnancy. If you swallowed toy slime early in pregnancy while the baby was still developing your doctor may offer you a more detailed scan.

If you have swallowed toy slime and experienced symptoms of toxicity (see above), additional monitoring to ensure that the baby is growing and developing as expected may be recommended.

Are there any risks to my baby if the father has used toy slime?

We would not expect any increased risk to your baby if the father had contact with toy slime before or around the time you became pregnant.

Who can I talk to if I have questions?

If you have any questions regarding the information in this leaflet please discuss them with your healthcare provider. They can access more detailed medical and scientific information from

How can I help to improve drug safety information for pregnant women in the future?

Our online reporting system (MyBump Portal) allows women who are currently pregnant to create a secure record of their pregnancy, collected through a series of questionnaires. You will be asked to enter information about your health, whether or not you take any medicines, your pregnancy outcome and your child's development. You can update your details at any time during pregnancy or afterwards. This information will help us better understand how medicines affect the health of pregnant women and their babies. Please visit the MyBump Portal to register.

General information
Sadly, miscarriage and birth defects can occur in any pregnancy.

Miscarriage occurs in about 1 in every 5 pregnancies, and 1 in every 40 babies are born with a birth defect. This is called the ‘background risk’ and happens whether medication is taken or not.

Most medicines cross the placenta and reach the baby. For many medications this is not a problem. However, some medicines can affect a baby’s growth and development.

If you take regular medication and are planning to conceive, you should discuss whether your medicine is safe to continue with your doctor/health care team before becoming pregnant. If you have an unplanned pregnancy while taking a medicine, you should tell your doctor as soon as possible.

If a new medicine is suggested for you during pregnancy, please make sure that the person prescribing it knows that you are pregnant. If you have any concerns about a medicine, you can check with your doctor, midwife or pharmacist.

Our Bumps information leaflets provide information about the effects of medicines in pregnancy so that you can decide, together with your healthcare provider, what is best for you and your baby.