Placental Lead and its Interaction with Some Essential Metals among Women from Lucknow, India

摘要

Objective: The placenta connects and separates two genetically distinct individuals: the mother and the fetus. There is no placental-fetal barrier blocking lead transport, placing the fetus at high risk from lead exposure. The placenta has been investigated as a possible indicator of environmental exposures. Recent studies have been focused on the interaction between toxic and essential metals in placenta as there is little information on the levels of lead and essential metals in human placental tissue in Indian scenario. Material & Methods: The present study was designed to determine the status of lead and some essential metals in placental tissue of women residing in and around, Lucknow, India. Sixty pregnant women attending the local maternity home in the city were recruited to determine the concentrations of lead (toxic metal) and zinc, copper, iron & calcium (essential metals) using atomic absorption spectrophotometry. Results: The mean±SD levels of placental lead was 0.35 ± 0.30μg/g which is lower than those reported in Australia (0.56μg/g) & Poland (0.50μg/g), and slightly higher than Spain (0.11μg/g). The mean ± SD (range) of placental zinc, copper, iron & calcium was found to be 7.67± 2.99 μg/g (0.47-13.75), 1.03 ± 0.55 μg/g (0.49-3.41), 76.42 ± 20.13 μg/g (17.67-135.25), 90.46 ± 112.47 μg/g (1.77-420.5) respectively. On the basis of parity, placental lead level was significantly higher (p<0.05), while copper and zinc were significantly lower (p<0.05, p<0.01 respectively) in multipa-rous cases as compared to nulliparous. Placental lead levels had significant negative correlation with zinc levels (r= -0.35, p<0.05). Conclusion: The results suggested that increased lead level affect the essential metal level and its level increased with parity whereas, there was a depletion of maternal stores of essential elements (Zn, Cu, Fe and Ca) with increasing parity.