Assessment of lead levels in maternal blood samples by graphite furnace atomic absorption spectrometry and influence of maternal blood lead on newborns

Abstract

Since fetal exposure to lead begins at the 21st week of pregnancy, the fetus is at high risk from maternal lead exposure. Although the placenta, an interface between the developing fetus and the mother, has mechanisms that restrict the entry of toxicants, it cannot protect the fetus from exposure to lead from the mother’s blood. Even low-level lead poisoning causes neuro-developmental toxicity in children including mild mental retardation, low intelligence quotients (IQ) and attention span, reading and learning disabilities, hyperactivity and behavioral problems. Also, lead exposure during pregnancy has been shown to increase the risk for abortions, premature births and prenatal deaths. The objective of this study was to detect whether or not maternal blood lead has an effect on newborns. This study involved 95 healthy, non-smoking, non-anemic pregnant women who have lived in Ankara, Turkey, for more than 3 years. Maternal blood samples were obtained from Ankara University, Gynecology Department of Faculty of Medicine, Dikimevi, Ankara, Turkey. Infant characteristics such as placental weight, birth weight, birth length and head circumference were recorded. Maternal blood lead levels were quantified using Varian AA240Z Graphite Furnace atomic absorption spectrometry (GFAAS), equipped with Zeeman background correction. The method showed linearity in the range of 0–100 µg/L, with a detection and quantification limit equal to 0.34 µg/L and 1.03 µg/L respectively. Maternal blood levels ranged between 12.27 and 433.22 µg/L. The mean maternal blood lead levels were found as 41.80±33.97 ppb. No statistically significant correlation was found between maternal blood lead and birth weight (r=-0.128, p=0.216), birth length (r=-0.081, p=0.434), head circumferences (r=-0.106, p=0.308) and placental weight (r=-0.021, p=0.840).