Monitoring survey of the use patterns and pesticide residues on vegetables in the Niayes zone, Senegal

• Published in: Chemosphere (Oxford) 2016-02, Vol.144, p.1715-1721
• Main Authors: Diop, Amadou, Diop, Yérim M., Thiaré, Diène D., Cazier, Fabrice, Sarr, Serigne O., Kasprowiak, Amaury, Landy, David, Delattre, François
• Format: Article
• Language: English
• Subjects: Agriculture - methods; Brassica; Brassica - chemistry; Brassica - growth & development; Chemical Sciences; Chlorpyrifos; Contamination; Environmental Monitoring - methods; Farming; Humans; Lactuca - chemistry; Lactuca - growth & development; Lettuces; Lycopersicon esculentum; Monitoring; Pesticide Residues - analysis; Pesticides; Residues; Senegal; Solanum lycopersicum - chemistry; Solanum lycopersicum - growth & development; Surveys and Questionnaires; Use patterns; Vegetables; Vegetables - chemistry; Vegetables - growth & development
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2015.10.058

The main objective of this work was to determine the impact of pesticide use practices on vegetables contamination in the Niayes zone of Dakar. A preliminary survey involving 200 farmers, showed the application of pesticides belonging to different groups on vegetable crops. Use practices in terms of application intervals and methods, measuring tools and dosage were not in compliance with good agricultural practices. In view of survey results, investigations on vegetable contamination were conducted. Therefore, 175 vegetable samples including cabbage (31 samples), lettuce (88 samples), tomato (57 samples) collected from four sites of the Niayes zone during four campaigns, were analyzed for residues of 21 pesticides, eighteen of which (18) were cited to be used by farmers. The results indicated that 65% of tomato samples, 71% of lettuce and 93% of cabbage contained one or more detectable residues. Among the monitored pesticides dicofol, chlorpyrifos, DDTs, dimethoate, and λ-cyhalothrin were the most predominant, found in at least 35% of samples for each vegetable. The frequencies of pesticide detection were, generally in agreement with the citation frequencies. The results provided important information on vegetable contamination status and pointed an urgent need to control pesticide use. •Pesticide residues in vegetables were investigated after a preliminary field survey.•Survey results revealed use of various pesticides, some of them banned for agriculture.•Analytical studies showed vegetables contamination at levels higher than that permitted.•Contamination was mainly due to dicofol, chlorpyrifos, dimethoate and λ-cyhalothrin.•Pesticide detection frequencies were in agreement with the frequencies of use.