Calabash chalk: Your Questions Answered

Tuesday 15 October 2002

Find out more Calabash Chalk.

What is Calabash chalk?

Calabash chalk is a type of chalk sold in ethnic stores and markets, which comes in a variety of forms from powders, moulded shapes and blocks.

It's also known as Calabar stone, La Craie or Argile in French, Nzu by the Ibo of Nigeria, Mabele by the Lingala speaking people of Congo (ex-Zaire).

What is Calabash chalk used for?

Calabash chalk is not a conventional food, but is eaten by some pregnant women to alleviate morning sickness.

It is traditionally used by women in the Nigerian and wider West African community.

Why is the Agency advising people, including pregnant and breastfeeding women, not to eat Calabash chalk?

The Food Standards Agency was made aware of a problem with calabash chalk by the London Borough of Greenwich after results of sampling taken locally indicated high levels of lead. Tests of samples taken by the Agency also showed high levels of lead.

Exposure to lead may result in a number of harmful effects, and the developing child is particularly at risk of effects on the nervous system. Calabash chalk is eaten by pregnant women, and sometimes by breastfeeding women, and so our advice aims to protect the unborn child and the breast-fed infant.

Anyone who has been eating calabash chalk and is concerned about their health should contact their GP or health visitor.

What controls are there on the amount of lead that can be present in food?

There is no statutory limit for lead in Calabash chalk. However there is a World Health Organisation safety guideline that is the amount of lead people can be safely exposed to. This takes into account exposure from the diet, water, environmental and other factors.

Lead intake from food is very low, just one-tenth of the guideline, but anyone taking Calabash chalk would significantly increase their lead intakes and could exceed the safety guideline.

For example, anyone taking 60g a day of the most contaminated product sampled so far would exceed the safety guideline 4.5 fold, before taking into account any additional exposure from other sources.

What other action is the Agency taking?

The Agency is advising that people, particularly pregnant and breast-feeding women should not eat Calabash chalk.

A Food Hazard Warning has been issued to request that Local Authorities visit food businesses and remove the product from sale, subject to testing for levels of lead.

The Agency also intends to raise with the European Commission the possibility of proposing EU-wide measures to prohibit the sale of Calabash chalk.

The Agency and the Department of Health will work with health professionals and consumer groups to communicate this information to pregnant and nursing mothers, particularly in the communities who are likely to use Calabash Chalk.

Where does Calabash chalk come from?

Calabash chalk is most likely to be imported from Western Africa.

How is it different from 'normal' chalk?

Chalk is a naturally occurring mineral, which is chiefly made up of fossilised seashells.

We believe that Calabash chalk may either occur naturally, in which case it is simply chopped into small blocks, or, it is produced from clay and mud which may be mixed with other ingredients including sand, wood ash and sometimes salt.

The resulting product is moulded and then heated to produce the final product.

Is lead normally found in chalk?

Yes. Chalk naturally contains a range of mineral impurities including lead. It can occur naturally in chalk at much higher levels than are generally found in food.

Levels of lead in chalk up to 40 mg/kg are known to occur.

How much lead do we normally take in from our diet?

Lead is present in the environment naturally or as a result of mining and smelting activities and vehicle exhaust fumes and occurs in most foods in very small amounts

In the most recent survey of lead in the UK diet, an average consumer’s exposure to lead from food was around one tenth of the internationally agreed safety guideline for lead.

Is the level of lead in food safe?

The FSA regularly measures the levels of lead and other heavy metals in the average UK diet. The levels of lead in the diet have been falling since 1980, and are now the lowest we have measured.

I am pregnant at the moment and am taking Calabash chalk - what should I do?

Stop taking it. Lead builds up in your body over time. If you stop using Calabash chalk, then the amount of lead in your body will start to fall, and the risk to your baby will decrease.

Anyone who has been eating calabash chalk and is concerned about their health should contact their GP or health visitor.

I am breastfeeding and have been taking Calabash chalk. What should I do?

If you are currently breastfeeding stop taking Calabash chalk.

You should not stop breastfeeding - breastfeeding is accepted as the best form of nutrition for infants to ensure a good start in life. The transfer of lead into breast milk is low, and the benefits of breastfeeding outweigh the risks. Breastfeeding confers significant short and long term health benefits for both mother and infants beyond the period of breastfeeding itself.

What can I use instead of Calabash chalk to alleviate morning sickness?

You should consult your doctor, health visitor or midwife.

Indigestion tablets and remedies contain chalk.Should I stop taking these?

The amount of lead permitted in licensed medicines is subject to strict controls that are the responsibility of the licensing authority, the Medicines Control Agency.

Are there any other alternative remedies that I should avoid if I am pregnant?

Always consult your doctor or health visitor before taking any remedies or medicines during pregnancy.

Graphic version of this page