Lead intoxication in human being has been documented since the second century BC and its deleterious effects continue to be a major health hazard for the population, it is demonstrated that lead exposure might decrease the defense mechanism of the cell to the oxidative stress, and therefore, elevate the reactive oxygen species (ROS) generation which enhance vascular reactivity. Since vitamin E (Vit. E) and vitamin C (Vit. C) are natural antioxidants, changes in their status may reflect alterations in free radical production rate and their concentrations are biological markers of oxidative stress. This study was conducted to determine the relationship between maternal blood lead levels and the antioxidants Vit.E and Vit.C in a step to understand the mechanism of action of lead and its possible influence on maternal blood pressure and fetal growth at the lower community exposure levels.
The study included, 42 patients with pregnancy induced hypertension (PIH) with or without proteinuria, 31 patients with fetal growth retardation (FGR) and 23 women with uncomplicated pregnancy. We demonstrated that, the maternal blood lead levels were significantly high in the PIH (30.5 ±0.978 μg/dl) and FGR groups (28.87 ±1.21 μg/dl) as compared with the uncomplicated pregnancy group (17.82 ±110μg/dl) at P≤0.00l Vit.E concentrations were significantly lower in both PIH and FGR (0.941 ±0.033 mg/dl and 0.866 ± 0.055 mg/dl respectively) when compared with normal group (2.00±0.085 mg/dl). Regarding Vit.C in the 2 studied groups there was significantly low levels in PIH group (0.772 ±0.030 mg/dl and FGR (0.847 ±0.039 mg/dl) in comparison with control group (l.23 ±0.06 mg/dl). We observed significant negative correlation between maternal blood lead levels and Vit.E in PIH and FGR group. A significant negative correlation was also observed between maternal lead levels and Vit.C in both studied groups.
We concluded that high blood lead levels in pregnancy are associated with low Vit.E , Vit.C, FGR and PIH. Such association or relationship could not be causal and more longitudinal studies are needed to confirm the link between lead, lipid peroxidation, antioxidants and pregnancy complications. This study may help in raising our consciousness of our environment and the need to protect us. The lack of effective and safe treatments for low-level intoxication has to promote environmental intervention to control different sources of lead to reduce lead burden among women and their newborns and to protect the fetus from other intrauterine toxic exposure that might be injurious.