Genotoxic pressure of vineyard pesticides in fish: field and mesocosm surveys.

The present study deals with the genotoxicity assessment of vineyard pesticides in fish exposed in the field or in mesocosm conditions. Primary DNA damage was quantified as strand breaks using the single cell gel electrophoresis assay (Comet assay) applied to fish erythrocytes. In a first experiment, a significant genotoxic effect was observed following an upstream-downstream gradient in early life stages of brown trout (Salmo trutta fario) exposed in the Morcille River contaminated by a mixture of vineyard pesticides during three consecutive years. The pronounced response in terms of DNA damage reported in the present study could argue for a high sensitivity of fish early life stage and/or a high level of exposure to genotoxic compounds in the Morcille River. This stresses the interest in using trout larvae incubated in sediment bed to assess genotoxic compounds in the field. In a second experiment, adult European topminnow (Phoxinus phoxinus) were exposed in water running through artificial channels to a mixture of diuron and azoxystrobin, two of the main pesticides detected in the Morcille watershed. As compared with the unexposed channel, a 3-5-fold increase in the DNA damage was observed in fish exposed to chronic environmental pesticide concentrations (1-2 microg L(-1) for diuron and 0.5-1 microg L(-1) for axoxystrobin). A single 6h pulse of pesticide (14 microg L(-1) of diuron and 7 microg L(-1) of azoxystrobin) was applied to simulate transiently elevated chemical concentrations in the river following storm conditions. It did not increase genotoxicity. After a 1-month recovery period, DNA damage in exposed fish erythrocytes recovered to unexposed level, suggesting possible involvement of both repair mechanisms and cellular turnover in this transient response. This work highlights that vineyard treatment by pesticides and in particular diuron and azoxystrobin can represent a genotoxic threat to fish from contaminated watershed rivers.

Pediatric poisonings from household products: hydrofluoric acid and methacrylic acid.

Household products continue to be a cause of poisoning morbibidity and mortality. Young children frequently are exposed to cleaning products and cosmetics in the course of exploring their environment. Most of these exposures are insignificant, but some result in death or permanent disability. This review discusses two products that have been responsible for serious injury and death in children: hydrofluoric acid and methacrylic acid. It also discusses federal initiatives designed to protect children from these and other household hazards.

A fatal laboratory accident with toxic gases inhalation.

Three university students were exposed to toxic vapours (acryloyl chloride 96% and methacrylic anhydride 94%) in a laboratory accident. They all gave a history of minimal exposure and presented with mild symptoms. One patient died on the same day. The other two cases were uneventful. This paper reports on these three cases, followed by a discussion on irritant gas intoxication.

[Organic dementia among dental technicians: a cross-sectional investigation of dental technicians using opticians as control]. / Organisk demens blandt tandteknikere: en tvaersnitundersogelse af tandteknikere med optikere som kontrolgruppe.

The preparation methylmethacrylate (MMA) an organic solvent which is employed inter alii in the production of prostheses, is regarded as neurotoxic. With the object of illustrating to what extent dental technicians have symptoms compatible with organic dementia as compared with a control group, a cross-sectional questionnaire investigation was undertaken in a population consisting of 256 dental technicians and 160 opticians, all of whom were professionally active. The percentage replies for the two group were 88 and 85 respectively. The two groups do not differ from one another as regards background variables with the exception of age and adjustments are made for this in the analysis. The results demonstrate that there is a statistically higher prevalence of the majority of acute and also chronic symptoms among dental technicians than among opticians. The symptom pattern and the presence of information and selection bias are discussed and it is concluded that this investigation confirms the hypothesis that symptoms compatible with organic dementia are commoner among dental technicians. The results raise the suspicion that MMA may cause acute and chronic damage to the central nervous system, even after very slight exposure. Revision of the occupational environment of dental technicians, including the current hygienic limits for MMA, is recommended.