LAUSR

Henna grows across Africa and Asia, where it has been used as a natural reddish dye for hair and skin since time immemorial. Although the U.S. Food andDrugAdministration (FDA) considers natural henna safe for use on hair (although not skin), its cosmetic properties are sometimes enhanced by the addition of dangerous ingredients, including lead. WhenDilek Battal, an associate professor in the Department of Pharmaceutical Toxicology at Mersin University in Turkey, decided to study hazardous additives in henna, one of her students visited popular henna shops to obtain samples. But most henna merchants—who mix their products themselves and add their own special ingredients—did not want to give her samples. Once the investigators managed to obtain some of the powders, the reason for their reluctance became clear. All 25 henna samples contained trace amounts of lead, along with other heavy metals and the highly allergenic colorant p-phenylenediamine. At least four of them contained no henna at all. The amounts of lead found in these and other studies may fall below limits suggested by agencies such as the FDA, which currently recommends no more than 10 lg=g (expressed as ppm) lead in cosmetics as an impurity. However, the frequent and long-term use of contaminated cosmetics raises the risk of cumulative exposure. Lead persists in the body for decades. In pregnant women, lead has been associated with spontaneous abortion, hypertension, and poor birth outcomes. During pregnancy, it can be resorbed from a woman’s bones into her blood, exposing her developing fetus. Perhaps the best-known consequences for children exposed to lead are neurotoxic effects. Relatively low exposures are associated with deficits in intelligence quotient, cognitive and behavioral disorders, and reduced motor skills. In one U.S. study of adults, higher cumulative lead exposure was associated with lower cognitive scores at 52–79 years of age. Other associated health effects in adults include hypertension, coronary heart disease, and other cardiovascular-related diseases. “Everywhere on Earth, I think, people are familiar with the fact that lead can poison and that people are poisoned by lead,” says Andrew McCartor, the vice president of strategy and partnerships at Pure Earth, a nonprofit that works to help clean up and prevent toxic pollution around the world. “But I don’t think that people realize the extent to which there is broad-based lead poisoning across entire populations.” Over the years, campaigns to remove lead from gasoline and paint have been real public health success stories. However, lead still hides in many industrial sources, foods, and spices, as well as in everyday cosmetics, says researcher Emmanuel ObengGyasi, an assistant professor of environmental health and safety at North Carolina Agricultural and Technical State University. Lead often turns up in cosmetics as a contaminant, possibly because it was in the same rock from which mineral-based colorants andmica powder were made. Obeng-Gyasi says it may also be added intentionally because lead makes cosmetic colors pop