Efecto del tiempo y las condiciones de almacenamiento sobre la actividad de las colinesterasas / Effect of time and the conditions of storage in the activity of the cholinesterases

Se evaluó la estabilidad de la colinesterasa plasmática y la colinesterasa eritrocítica a temperatura ambiente, 4§C y -20 §C, durante un periodo de tres meses. Se determinó que la colinesterasa plasmática es estable en refrigeración y congelación. A temperatura ambiente la actividad de esta enzima disminuye significativamente en una semana. Por su parte la colinesterasa eritrocítica es estable únicamente en refrigeración. El proceso de congelamiento y descongelamiento provoca disminución importante en la actividad de la enzima. En las muestras conservadas por un día a -20 §C, la actividad de la enzima eritrocitaria fue enre 10 y 20 por ciento más baja que la actividad basal. A temperatura ambiente la actividad de esta enzima disminuye en forma importante en una semana. Palabras clave: colinesterasa plasmática, colinesterasa eritrocítica, plaguicidas, organofosforados, carbamatos, toxicología

Distributions of some insecticides in body fluids and tissues n decedents intoxicated with these chemicals

This paper described the body fluids and tissue distribution of four insecticides; one belongs to organochlorine compounds [endosulfan] and three organophosphate insecticides [malathion, chlorpyrifos and diazinon], in four suicidal human cases in Kuwait, who died after ingestion of insecticidal preparations containing these chemicals. The cases were autopsied and distribution of these chemicals were studied in stomach contents, blood, urine, bile and different tissues. Gas chromatography ion trap detector [GC-ITD] was used as analytical tool for the identification and quantitation of insecticides during this work. The study revealed higher concentrations of these insecticides in the stomach contents. Higher concentrations of malathion and endosulfan were detected in bile. Diazinon and chlorpyrifos were found at higher level in spleen. The least amount of these insecticides was recorded in muscle tissues

Association between water pollution and insecticides and their residues in fish

Forty water samples were collected from Lake Maryut and Alexandria Hydrodrome. Twenty samples were collected from each locality during summer months, at the same time, other 40 samples of Tilapia galilea fish, each weighed 100-150 g, were obtained from the same localities from which water samples were collected. After estimation of some organochlorine and organophosphorus insecticide residues in water and fish samples using gas liquid chromatography [GLC]. The results were evaluated according to water quality criteria [1968] and Joint FAO/WHO [1978]. The obtained data indicated a correlation between detected insecticides residues DDT, dieldrin and dimethoate in fish and their concentration in water. The data also indicated that the level of insecticides in Alexandria Hydrodrome water and fish samples is higher than in Maryut samples. The insecticide hazards as well as public health importance were discussed

Organochlorine pesticide residues in tilapia species fish and the influence of thermal treatment and freezing storgement on their levels

Thirty fish samples of Tilapia species were collected randomly from Alexandria fish markets. The samples were screened for organochlorine pesticide [DDT, dieldrin and lindane] in fish muscles. The mean concentrations of DDT, dieldrin and lindane in fish muscles were 3.67 +/- 0.59, 0.17 +/- 0.03 and 0.75 +/- 0.21, respectively. No pesticide residues could be detected in positive samples after being exposed to heat treatment [roasting for 20 minutes and frying in oil for 15 minutes]. However, freezing for one month at -20C had slight significant effect on pesticide residues, while freezing storage for up to two months was sufficient for destruction of such residues in tested samples. The toxicity and public health significance of organochlorine pesticide were discussed