Our present knowledge of the human health effects of methylmercury exposure is derived from study of major outbreaks of human poisonings in Japan and Iraq and experimental studies on primates. Methylmercury readily passes through such physiological barriers as the blood-brain barrier, blood-testes barrier, and the placenta. Its major pathological effects are on the nervous and reproductive syst...

Abstract. Methylmercury accumulated at the top of aquatic food chains constitutes a toxicological risk to humans and other predators. Biomagnification methylmercury takes place among vertebrates higher trophic levels, but this process is less elucidated in benthic invertebrates lower levels. Therefore, we investigated accumulation from elimination inorganic mercury sea star Asterias rubens (L.)...

Developmental exposure to methylmercury has behavioral effects that extend into adulthood and aging. In this study, methylmercury's prolonged effects on the acquisition of choice and sensitivity to changes in reinforcement rates were studied. Pregnant female rats were exposed to drinking water containing 0, 0.5, or 6.4 ppm Hg as methylmercury, resulting in about 40 and 500 microg/kg/day of merc...

This document outlines a strategy for integrated mercury investigations linked to restoration and adaptive management of the San Francisco Bay and Sacramento-San Joaquin Delta ecosystem (termed the Bay-Delta ecosystem and defined as the combined watershed, Delta, and Bay). Ecosystem restoration and management of the Bay-Delta ecosystem are complicated by mercury contamination from historic mini...

Human activities such as mining, smelting, and coal combustion dis­ perse mercury that can be methylated by bacteria to produce methyl­ mercury, a potent neurotoxicant. Methylating bacteria thrive in aquatic sediments rich in organic matter, and methylmercury biomagnification eventually leads to heavy contamination of top predators, including fish consumed by humans. Although fish and seafood a...

Epidemiological studies have demonstrated the developmental neurotoxicity associated with prenatal methylmercury exposure (Grandjean and Landrigan, 2006); However, susceptibility to methylmercury toxicity may be increased by genetic factors. This observation raises the question of possible dependence of developmental neurotoxicity on genetic predisposition. A few years ago, a National Research ...

Organic mercury compounds were first described in the 1800s, with fatal cases of methylmercury poisoning reported in 1865. Early reports described a distinct set of symptoms of methylmercury toxicity, including altered sensation in the face and extremities, tunnel vision, deafness , loss of coordination, and impaired speech. Nearly a century later, against a backdrop of widespread environmental...

MARŠÁLEK P., SVOBODOVÁ Z. (2006): Rapid determination of methylmercury in fish tissues. Czech J. Food Sci., 24: 138–142. The aim of the present study was to develop a rapid and inexpensive method for the determination of methylmercury in fish tissues based on GC/ECD instrumentation. The new method is based on acidic digestion in hydrochloric acid and subsequent extraction with toluene. Methylme...

We assessed mercury contamination of water, sediment, and selected aquatic biota from two lagoons in the Apostle Islands National Lakeshore (southern Lake Superior). These nearshore lagoon systems appear to be mercury-sensitive environments with unusually high rates of production of methylmercury, a highly toxic compound that readily bioaccumulates in aquatic food webs. Concentrations of methyl...

Environmental contaminants can alter the course of neural development, with consequences that appear in behavior. Such effects extend into adulthood and sometimes accelerate the rate of aging, even when exposure ceases by birth. The neurotoxicant methylmercury provides an interesting case study that reveals much about how disrupted neural development has lifelong consequences. Methylmercury als...