scispace - formally typeset
Search or ask a question

Showing papers by "Donna Mergler published in 1998"


Journal ArticleDOI
TL;DR: Results suggest dose-dependent nervous system alterations at hair mercury levels below 50 micrograms/g, previously considered a threshold for clinical effects, are suggested and are consistent with the current knowledge on methyl-mercury poisoning.

323 citations


Journal ArticleDOI
TL;DR: The sandification and podzolisation that is characteristic of the evolution of numerous pedological systems in the equatorial Amazon could be responsible for exportation of the naturally accumulated Hg by acidic complexation and migration to the black waters of the Amazon.

222 citations



Journal ArticleDOI
TL;DR: Increased consumption of lake fish was associated with higher blood mercury concentrations among 289 residents of Southwest Quebec living on the southern bank of the Upper St. Lawrence River System and this increase was reflected in the organic fraction and to a lesser extent with total blood mercury.

76 citations


Journal Article
TL;DR: Paired analyses showed that fisheaters had higher levels of blood organic mercury and lead, and the profile of deficits is consistent with diminished capacity for information processing.
Abstract: Pollution of hydrographic basins has affected the flora and fauna that thrive in these aquatic ecosystems, and fish, which constitute an important food resource, often contain a plethora of potentially toxic chemicals. In a major research project on early neurotoxic effects ofenvironmental exposure to manganese among residents in Southwest Quebec, fish consumption from 2 lakes of the Upper St. Lawrence River System, was surveyed as a potential confounding factor. Participants were selected using a random, stratified sampling strategy from lists of the Quebec Health Plan. Following exclusions, 273 men and women between 20-69 years were retained for the present analysis. A total of 103 (37.7%) reported eating fish from the Upper St. Lawrence. Although fisheaters and non-fisheaters were similar for most socio-demographic variables, significantly more fisheaters (65.2%) reported consuming alcoholic beverages as compared to non-fisheaters (42.4%) (Chi Sq. <0.01). To eliminate this possible bias, fisheaters were matched to non-fisheaters for the variables sex, alcohol consumption (never or occasionally vs. regularly), age (±5y) and education (±2y). A total of 63 matched pairs were thus created. Paired analyses (t-test or Signed Rank) showed that fisheaters had higher levels of blood organic mercury and lead. Analysis of nervous system functions revealed that both groups performed similarly on tests of sensory function, visual memory and recognition, fine motor performance and some motor tests, but fisheaters performed significantly more poorly (p<0.05) on tests requiring cognitive flexibility, word naming, auditory recall, and more complex motor tasks. The profile of deficits is consistent with diminished capacity for information processing. These observations were made within a study that was not specifically designed to examine the effects of fish eating from these two lakes, and the characterization of fish dietary habits has many limitations. Nevertheless, the findings are sufficiently compelling to warrant further studies, since fish from the Upper St. Lawrence Lakes are known to contain multiple neurotoxic substances.

41 citations




Journal ArticleDOI
TL;DR: Workplace Exposures beyond the Workplace: Exposure Assessment for a Pilot Study of Effects of Workplace Exposesures on Family Life as discussed by the authors, is an example of such a study.
Abstract: (1998). Workplace Exposures beyond the Workplace: Exposure Assessment for a Pilot Study of Effects of Workplace Exposures on Family Life. Applied Occupational and Environmental Hygiene: Vol. 13, No. 9, pp. 629-633.

2 citations