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Dermal and oral toxicity of malathion in rats
Sabina Tós-Luty1, Daniela Obuchowska-Przebirowska, Jadwiga Latuszyńska
1Department of Pathomorphology, Institute of Agricultural Medicine, P.O. Box 185, 20-950 Lublin, Poland.
Abstract:
The aim of the study was the evaluation of dermal and oral toxicity of malathion based on the results of histopathologic and ultrastructural tests. The standard of the pesticide - IPO 460 Malathion was used in the study. The preparation was suspended in oil emulsion. The study was conducted on Wistar rats. Dermal toxicity was examined in 2 groups of experimental rats. The animals were applied 8 mg (1/100 LD(50)) and 16 mg (1/50 LD(50)) of the preparation on the tail skin for 4 hours daily for a period of 28 days. In the case of oral toxicity, a dose of 1/50 LD(50) malathion was used. The amount of 1 ml (11.2g) of the preparation was administered intragastrically by stomach tube for 28 days. In both experiments the control animals were administered only the emulsion used for suspending the pesticide. The following organs were subject to histopathologic and ultrastructural evaluation: liver, kidneys, heart and lungs. The histopathologic and ultrastructural changes observed showed various degrees of intensity according to the route of malathion administration and the size of the dose applied. Dermal application of the pesticide in a smaller dose did not cause histopathological changes in the organs of the animals, while the administration of a higher dose resulted in changes only in the liver. Changes on the ultrastructural level occurred in all organs and were dose-dependent. After oral administration of malathion, both histopathologic and ultrastructural changes observed in all organs were more intensified than after dermal application.
Insights
This study evaluated malathion toxicity in rats. Oral malathion caused more severe histopathological and ultrastructural changes in organs than dermal exposure, with effects being dose-dependent.
Area of Science:
- Toxicology
- Histopathology
- Electron Microscopy
Background:
- Malathion is a widely used organophosphate pesticide.
- Understanding its toxicity is crucial for public health and environmental safety.
- Histopathological and ultrastructural evaluations provide detailed insights into cellular damage.
Purpose of the Study:
- To assess the dermal and oral toxicity of malathion.
- To investigate the histopathological and ultrastructural effects of malathion on key organs.
- To compare toxicity levels based on administration route and dosage.
Main Methods:
- Wistar rats were used for dermal and oral toxicity testing.
- Dermal exposure involved applying malathion to rat tails at 1/100 and 1/50 LD(50) doses for 28 days.
- Oral exposure involved intragastric administration of 1/50 LD(50) malathion for 28 days.
- Histopathological and ultrastructural analyses were performed on liver, kidneys, heart, and lungs.
Main Results:
- Dermal application of the lower malathion dose showed no histopathological changes.
- Higher dermal dose caused liver histopathological changes.
- Ultrastructural changes occurred in all tested organs and were dose-dependent with dermal exposure.
- Oral malathion administration resulted in more intensified histopathological and ultrastructural changes in all organs compared to dermal exposure.
Conclusions:
- Malathion toxicity is dependent on the route of administration and dosage.
- Oral exposure to malathion induces more significant organ damage than dermal exposure.
- Ultrastructural changes indicate malathion's potential to affect multiple organ systems at the cellular level.
