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Daily supplementation with 1000 mg of ascorbic acid results in a significant decrease of blood-lead levels associated with the general population. Ascorbic acid supplementation may provide an economical and convenient method of reducing blood-lead levels, possibly by reducing the intestinal absorption of lead.

Studies of maternal amniotic fluid and serum at delivery have revealed the presence of toxic metals or deficiencies of essential metals associated with high-risk pregnancy. Essential and toxic metal levels were studied in 29 preeclamptic and 101 normal pregnancies. The authors grouped the samples according to the following gestation ages: 33-36 wk (48 normal and 10 preeclamptic) and 37-40 wk (53 normal and 19 preeclamptic). The metals studied were calcium, magnesium, zinc, selenium, copper, cadmium, and lead. Comparisons of the 33-36-wk gestation group showed significant differences between normal and preeclamptic amniotic fluid in levels of lead, calcium, magnesium, zinc, and selenium. There were also significant differences in levels of magnesium, copper, zinc, cadmium, and lead during the gestation period of 37-40 wk. The changes observed in calcium and lead levels were consistent with the results of animal studies in which investigators have found depressed calcium transport associated with subacute or chronic lead poisoning, resulting in a physical syndrome similar to preeclampsia.

This study compares the semen levels of lead (Pb), cadmium (Cd), and aluminum (Al) in relation to live sperm in semen samples from 64 apparently healthy men. The measured levels were separated into live sperm count tertiles (<25% [18 subjects], 25-50% [26 subjects], and >50% [20 subjects]). The mean +/- SD for each group was calculated, and the difference between the means of the high and low tertiles were compared by ANOVA. Significant differences were observed between the high and low live sperm groups for Pb (p < 0.01) and Al (p < 0.05), but not Cd. Spearman's rank correlation between sperm viability and the semen plasma metal levels showed a direct relation to Mg (p < 0.05). However, there was an inverse relation to lead (p < 0.001), cadmium (p < 0.01), and aluminum (p < 0.01). There was no significant correlation between Ca and Zn. Linear regression between the live sperm counts and semen level of the three metals show that metal levels were inversely correlated with the percentage of live sperm (p < 0.001, < 0.01). Apparently, the presence of these metals in the environment and in seminal plasma exerts a toxic effect on sperm.

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