Lead acetate

About: Lead acetate is a research topic. Over the lifetime, 2636 publications have been published within this topic receiving 69739 citations.

Tissue levels of lead in experimentally exposed zebra finches (Taeniopygia guttata) with particular attention on the use of feathers as biomonitors.

Abstract: We tested experimentally whether zebra finch feathers can be used as a biomonitor for lead pollution, and we examined whether lead exposure influences the accumulation of zinc into feathers. Two groups of eight adult male zebra finches were dosed with, respectively, 0 and 25 ppm lead as lead acetate in their drinking water. After 30 days, lead-treated zebra finches accumulated significantly higher lead concentrations in brain, fat, kidney, liver, muscle, testes, and regrown outer tail feathers than control individuals. Lead levels in regrown outer tail feathers were significantly higher than in original outer tail feathers in the exposed group. The concentration of lead in original (not regrown) fifth tail feathers at the end of the experiment was significantly higher than lead levels in the original outer tail feathers. Our results indicate that lead in regrown feathers originates both from internal deposition and external contamination through the excretion of the uropygial gland during preening. Lead levels in regrown feathers were significantly correlated with levels in liver, kidney, and muscle, suggesting that feathers can be used as a biomonitor for lead. We found that lead had an influence on the metabolism of zinc. Zinc concentrations in the regrown feathers were significantly lower in the lead-treated group although zinc levels in the liver did not differ significantly. Moreover, lead and zinc concentrations in the feathers were significantly negatively correlated.

Behavioral effects of chronic exposure to low levels of lead in Drosophila melanogaster.

Abstract: Through human activity lead has become a serious environmental neurotoxin, known to affect activity levels, attention and both sensory and cognitive function in children. Study of lead would be facilitated by having a model system that could be manipulated easily and quickly. We find Drosophila melanogaster ideal as such, and we have been studying effects of lead on courtship, fecundity and locomotor activity. We raised Canton-S flies from eggs to adult day 6–7 on medium made with lead acetate solution (2–100 μg/g), or with distilled water, and we measured adult body lead burdens by means of Inductively Coupled Plasma Mass Spectrometry (ICP-MS). To measure courtship effectiveness, five virgin females and five virgin males were transferred into an empty vial and the number of females that mated within 20 min was recorded. To measure fecundity, all adult offspring from eggs produced by one female within 12 days of mating were counted. To measure locomotor activity, individual flies were transferred to a grid-labeled petri dish and the number of lines crossed in 30 s was counted. The number of females mating within 20 min was increased significantly by exposure to 2 or 8 μg/g lead, and was decreased significantly by exposure to 20 or 50 μg/g lead. Fecundity was increased significantly by exposure to 2 μg/g lead, but was unaffected by exposure to 20 μg/g lead. Locomotor activity was consistently higher for males than for females, and was significantly reduced only by exposure to 50 μg/g lead, and then only for males. We thus defined for Drosophila a lowest observable effect level (LOEL) of 2 μg/g lead, which is considerably lower than the doses shown previously to affect this animal. The dose–response curve was biphasic for the number of females mating within 20 min, an example of hormesis , a non-linear response that has been reported for low levels of stressors as diverse as pollutants and radiation. We hope from further studies with Drosophila to understand better how lead affects the developing nervous system, and thus ultimately its effects on children.

Effects of acute lead ingestion and diet on antibody and T-cell-mediated immunity in Japanese quail.

Abstract: This study investigated the interacting effects of acute lead exposure and different diets on antibody and T-cell-mediated immunity in Japanese quail (Coturnix coturnix). Nine quail (nine week old males) were assigned randomly to each group in a factorial experiment with four treatments and two diets. The treatments were 1) a positive control group fed 20 μg/g corticosterone, 2) a negative control group given no lead or corticosterone, 3) a low-lead group, and 4) a high-lead group. The low and high lead groups received 100 and 400 μg/ml lead as lead acetate in drinking water for 7 d. The two diets were poultry feed and ground corn. Control quail fed corn lost 13–14% of initial body mass, but lead-dosed quail fed corn lost 23–24%. All quail fed poultry feed gained body mass. On the corn diet, three high-lead and one low-lead quail died of lead poisoning. Corn increased the percentage of heterophils in white blood cells (P=0.0018) and decreased lymphocytes (P=0.019) and monocytes (P=0.0073). There was marginal evidence that lead increased the heterophil/lymphocyte ratio in corn-fed quail (P=0.064). Corn decreased the T-cell-mediated response to an intradermal injection of phytohemagglutinin (P=0.0001). Corticosterone suppressed this response more than lead. In corn-fed quail, lead suppressed the primary total antibody response to immunization with chukar partridge (Alectoris graeca) erythrocytes (P<0.05). Lead reduced the secondary total antibody and IgG responses in the low lead, corn group (P<0.05). Lead suppressed antibody-mediated immunity only at dosages that also caused clinical lead poisoning.

Effects of chronic exposure to sublethal concentrations of lead acetate on heme synthesis and immune function in red-tailed hawks.

Abstract: Red-tailed hawks were exposed to sublethal levels of lead acetate for periods of 3 or 11 weeks. Alterations in the heme biosynthetic pathway were demonstrated after the first week of exposure to 0.82 mg lead per kilogram body weight per day. Activity of erythrocyte porphobilinogen synthase (aminolevulinic acid dehydratase) was depressed significantly and did not return to normal levels until 5 weeks after the termination of lead treatments. A rapid and relatively brief increase in erythrocyte free protoporphyrin and a slower but more prolonged increase in its zinc complex were also demonstrated with exposure to this dose of lead for 3 weeks. Less substantial decreases in hematocrit and hemoglobin levels occurred but only in the longer experiment with exposure to higher lead levels. Short term, low level lead exposure did not effect immune function significantly in the hawks, as measured by antibody titers to foreign red blood cells or by the mitogenic stimulation of T-lymphocytes. Increased lead exposure produced a significant decrease in the mitogenic response but had no effect on antibody titers.