High umbilical cord blood lead levels and "calabar chalk" consumption amongst pregnant women in two hospitals in Cameroon

Abstract

Introduction: "Calabar chalk" is a lead-laden pica mostly consumed by pregnant women worldwide as a remedy for morning sickness. This clay material has been shown to have lead levels of up to 40mg per kilogram. Meanwhile blood lead levels, even at doses less than 10µg/dl will be toxic to humans and even worse-off to the fetus as it crosses the placenta. We, therefore, sort to determine the prevalence of "Calabar chalk" consumption amongst pregnant women and if it translates to higher umbilical cord blood lead levels. Methods: we carried out a cross-sectional study by prospectively and consecutively enrolling 300 pregnant women from December 2014 through February 2015. A questionnaire was administered to ascertain "Calabar chalk" consumption. The levels of lead in the umbilical cord blood of 51 participants of each group of those who consumed and didn't consume "Calabar chalk" were measured by spectrometry and compared using the T-test (p<0.05). Results: the prevalence of "Calabar chalk" consumption was 43.33%. This was mostly consumed during pregnancy only (46.34%), with higher rates observed amongst primigravidas. The mean umbilical blood lead levels amongst those who consumed and those who did not consume "Calabar chalk" was 39.19µg/dl and 25.33µg/dl respectively (P=0.111). Conclusion: the prevalence of "Calabar chalk" consumption was high in the pregnant women population. The overall umbilical cord blood lead levels were extremely high in both consumers and non-consumers. We recommend health education and chelation therapy to be considered.