Methylmercury developmental neurotoxicity: A comparison of effects in humans and animals

doi:10.1016/0892-0362(90)90091-P

Neurotoxicology and Teratology

Volume 12, Issue 3, May–June 1990, Pages 191-202

https://doi.org/10.1016/0892-0362(90)90091-P Get rights and content

Abstract

A qualitative and quantitative comparison of the neuropathological and neurobehavioral effects of early methylmercury (MeHg) exposure is presented. The focus of the qualitative comparison is the examination of how specific end-points (and categories of behavioral functions) compare across species. The focus of the quantitative comparison is the investigation of the relationship between MeHg exposure, target-organ dose and effects in humans and animals. The results of the comparisons are discussed in the context of the adequacy of the proposed EPA neurotoxicity battery to characterize the risk of MeHg to humans. The comparisons reveal several qualitative and quantitative similarities in the neuropathological effects of MeHg on humans and animals at high levels of exposure. Reports of neuropathological effects at lower levels are available for animals only, precluding any comparison. At high levels of exposure, specific neurobehavioral end-points affected across species are also similar. Effects at lower levels of exposure are similar if categories of neurobehavioral functioning are compared. Changes in the EPA test battery consistent with the results of the comparisons are discussed.

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Thus, disruption at any step of cell signaling during development could cause the defect. MeHg is a well-characterized teratogen and neurotoxicant in humans and wildlife (Bose-O’Reilly et al., 2010; Burbacher et al., 1990; Clarkson and Magos, 2006; Yang et al., 2020). Generally, total Hg levels in surface water are in the range of <5–20 ng/L, and MeHg concentration up to 4 ng/L (37% of total Hg) is found in natural surface waters (Ullrich et al., 2001).
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Methylmercury developmental neurotoxicity: A comparison of effects in humans and animals

Abstract

Toxicol. Appl. Pharmacol.

Repord. Toxicol.

Toxicol. Appl. Pharmacol.

Neurotoxicol. Teratol.

Environ. Res.

Environ. Res.

Pharmacol. Biochem. Behav.

Toxicol. Appl. Pharmacol.

Neurotoxicol. Teratol.

Sci. Tot. Environ.

Pharmacol. Biochem. Behav.

Pharmacol. Biochem. Behav.

Food Cosmet. Toxicol.

Dev. Brain Res.

Environ. Res.

Dev. Brain Res.

Exp. Neurol.

Toxicol. Appl. Pharmacol.

Toxicol. Appl. Pharmacol.

Pharmacol. Biochem. Behav.

Pharmacol. Biochem. Behav.

Intrauterine methylmercury poisoning in Iraq

Pediatrics

Prenatal methylmercury poisoning

Am. J. Dis. Child.

Collaborative behavioral teratology study: Results

Neurobehav. Toxicol. Teratol.

Retarded object permanence development in methylmercury exposed Macaca fascicularis infants

Dev. Psychol.

A Golgi and electron microscopic study of cerebellum in methylmercury-poisoned neonatal mice

Acta Neuropathol. (Berl.)

Abnormal neuronal migration, deranged cerebral cortical organization, and diffuse white matter astrocytosis of human fetal brain: A major effect of methylmercury poisoning in utero

J. Neuropathol. Exp. Neurol.

An outbreak of methylmercury poisoning due to the consumption of contaminated grain

Mercury

Prenatal methylmercury exposure: I: Alterations in neonatal activity

Neurobehav. Toxicol. Teratol.

Prenatal methylmercury exposure: II: Alterations in learning psychotropic drug sensitivity in adult offspring

Neurobehav. Toxicol. Teratol.

The toxicity of methylmercury

Behavioral effects of mercury and methylmercury

The selenium content in swordfish (Xiphias giadius) in relation to total mercury content

J. Environ. Sci. Health

Protective effects of freeze dried swordfish on methylmercury chloride toxicity in rats

Bull. Environ. Contam. Toxicol.

Selenium: Relation to decreased toxicity of methylmercury added to diets containing tuna

Science