Toxic substances in edible clay

Earth eating, known as geophagia, occurs all around the world. Small helpings of clay and limestone are supposedly beneficial for those suffering from abdominal pains or morning sickness. In the West such ideas have generally not fallen on fertile soil. Yet in the year 2012 edible clay is available in the Netherlands, arriving in the wake of African and Surinamese immigrants. They should, however, be careful with it. A recent study, by Rikilt and the Netherlands Food and Consumer Product Safety Authority, has shown that edible clay can contain high doses of dioxins. The research focused on thirteen products, such as Pimba and Mabele, which can be bought in the Netherlands. Master’s student Antonia Talidda also analysed twenty clay stones sent in by African WUR students from countries including Zimbabwe, Nigeria and Ivory Coast. High levels of dioxins were found in both categories. Pregnancy A worrying result, considering the damage that dioxins cause. They build up in our fat tissue and subsequently circulate in the body. Results from animal testing shows that they damage the development of unborn babies, and even after birth dioxins can still harm children because they end up in breast milk. It is therefore ironic that women predominantly eat the clay during pregnancy. Exactly how dangerous the edible clay is for breastfeeding babies remains unclear, explains Rikilt researcher Ron Hoogenboom. That is because we don’t know exactly how the intake of highly concentrated doses of dioxin affects the body. ‘Researchers are primarily trying to establish how much you can ingest before it represents a risky degree of "body burden".’ Nevertheless, the nutrition centre is discouraging women in the Netherlands from eating clay. Hoogenboom: ‘In the Netherlands there are plenty of other solutions available for issues such as mineral deficiency and nausea.’ RR The researchers will publish their results soon in Chemosphere.