Fate of lambda-cyhalothrin in kales, tomatoes and cabbage from rural setting in Kenya.

Abstract

A vegetable is any part of a plant that is consumed by humans as food as part of a savory course or me al. They are highly nutritious and form as key food com modity in the human consumption. They are also highly perishable due to their low shelf life. A diet rich in vegetables and fruits can lower bloo d pressure, reduce risk of heart disease and stroke, prevent so me types of cancer, lower risk of eye and digestive problems. When researchers combined findings from t he Harvard studies with several other long-term stu dies in the U.S. and Europe, and looked at coronary hear t disease and stroke separately, they found a simil ar protective effect: Individuals who ate more than 5 servings of fruits and vegetables per day had rough ly a 20 percent lower risk of coronary heart disease and st roke, compared with individuals who ate less than 3 servings per day. Pesticide residues are the major contaminants found in vegetables. Pesticides are us ed in management of pests and diseases in Agricultural an d Horticultural crops. They can leave adverse effe cts on the nervous system. Some harmful pesticides can cau se several hazardous diseases like cancer, liver, k idney, and lung damage. Certain pesticides can also cause loss of weight and appetite, irritability, insomnia , behavioral disorder and dermatological problems. Th ere are many pesticides in use today including; insecticides, acaricides, nematocides, herbicides, and avicides. Pyrethroids are the most commonly use d insecticides. The pyrethroids in use include; delta methrin, lambda-cyhalothrin and chismethrin. Lambda - cyhalothrin was analyzed in some selected vegetable s (kales, cabbages and tomatoes) in this study. The samples were obtained from different sellers in som e rural setting in Kenya known as Makuyu, during th e dry and wet seasons. They were extracted for the lambda -cyhalothrin using organic solvents. The residues w ere then determined using high performance liquid chrom atography (HPLC ) . The analysis of the data was done using t-test, regression analysis and ANOVA. In thi s case, lambda-cyhalothrin was analysed in vegetabl e samples obtained from the urban area (Nairobi Marke ts) during the dry and wet seasons. It was observed that the samples analysed during the dry season had high er residue levels of lambda-cyhalothrin (ranging fr om 0.0300 mg/kg to 0.3400 mg/kg), than those analysed during the wet season which, ranged between 0.0001 and 0.0040 mg/kg. The difference between the two season s was significant at 95 % confidence level, (t (8, 0.05) = 2.31 and t calculated =4.30). Almost all the samples analysed during the wet season had undetectable levels of lambda-cyhalothrin. The residue levels observed dur ing the dry season were higher than the FAO/WHO’s ADI of 0.02 mg/kg, but less than the FAO/WHO’s MRLs of 0.2 mg/kg (FAO/WHO, 1996), while the levels of lambda-cyhalothrin obtained during the wet seasons were all lower than the two bodies’ set standards.