This study was conducted to assess dietary exposure to pesticide residues and pesticide application practices leading to the presence of these residues among vegetable farmers in Arusha, Tanzania. Face-to-face interviews using semi-structured questionnaires (including 24-hour recall and food frequency questionnaire techniques) were conducted to collect information on pesticide application practices and vegetable consumption, from 76 farmers. A sample of ready-to-eat vegetables was collected from each farmer's household to determine the level of pesticide residues. Pesticide residues were analyzed by gas chromatography-mass spectroscopyA deterministic approach was used to assess dietary exposure to pesticide residues. Among the analyzed samples, 31.4% contained detectable levels of organophosphate residues. The detected organophosphates were dimethoate (mean, 8.56 mg kg-1), acephate (mean, 2.9 mg kg-1), profenofos (mean, 8.44 mg kg-1), dichlorvos (mean, 20.8 mg kg-1) and malathion (mean, 5.47 mg kg-1). The mean exposure for dimethoate (0.0021 mg kg-1 body weight (wt) day‑1 was higher than its corresponding acceptable daily intakes of 0.002 mg kg-1bwd‑1 resulting in hazard quotient of 1.044 with a consequent hazard index of 1.19 for organophosphates. Pyrethroid pesticides (permethrin, cypermethrin, and lambda-cyhalothrin) were also detected but at a lower frequency (17.1%) and hazard index (0.029). The exposure to pesticide residues was significantly associated with limited access to expert advice on pesticide application (p=0.031, adjusted odds ratio=6.56) and over-dosage (p=0.038, adjusted odds ratio=3.751).The risk may be minimized by increasing access to support by extension service providing guidance on good practices and ensuring application of appropriate doses for pesticides.

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Influence of vegetable processing on pesticide residues in ready-to-eat vegetables studied at the experimental level does not necessarily reflect actual situation at household level. This study assessed influence of household vegetable processing practices on pesticide residues in ready-to-eat vegetables at household level in Arusha, Tanzania. Data on vegetable handling practices were collected through observations and physical interviews in 70 households. Samples of raw and ready-toeat vegetables were collected from the households for pesticide residues analysis.Detectable pesticide levels were found in 46% of raw and 14% of ready-to-eat vege-

Information on the extent of pesticide residues in vegetables from Tanzania and risk of dietary exposure to these residues among vegetable consumers is limited. This research assessed the risk of dietary exposure of pesticide residues in vegetable farmers and individuals with non-communicable disorders in Arusha. Face-to-face interviews were conducted to assess pesticide application practices. Observations were made to assess effectiveness of vegetable processing practices at household level, in reducing pesticide residues. Two-point 24 hour recalls and food frequency questionnaire techniques were used to determine vegetable consumption. Raw and ready-to-eat vegetables were sampled and analyzed for pesticide residues using Gas Chromatography-Mass Spectroscopy. Dietary exposure to pesticide residues was estimated. The results showed that vegetables were contaminated with organophosphates, pyrethroids organochlorines, carbamates and benzoic acid pesticides. Endosulfan and dieldrin which are banned for use in agriculture in Tanzania were quantified in the vegetables at levels above their respective Maximum Residue Levels. Exposure estimations showed that 18.6% of vegetable farmers are at risk of exposure to organophosphates [Hazard index (HI); 1.19], mainly contributed by dimethoate. Individuals with NCDs are at risk of exposure to organophosphates (HI; 1.12) and organochlorines (HI; 1.08) mainly attributed to exposure to chlorpyrifos and endosulfan, respectively. Dietary exposures of pesticides are significantly associated with lack of advice from agricultural extension officers (adjusted odds ratio (AOD) = 6.56; P = 0.031), over-dosage of pesticides in vegetables (AOD = 3.751; P = 0.038) and lack of professional training on pesticide application practices (AOD = 3.37; P = 0.043). Washing vegetables in a bowl two or more times with changing the washing water after one use, (χ 2(1) = 6.56; P = 0.01) or peeling (χ 2(1) = 6.949; P = 0.008 is significantly associated with low levels of pesticides in ready to eat vegetables. Poor practices in washing of minor ingredients (tomato, carrot, sweet pepper and onions) such as washing by water that was previously used to wash the major ingredients has significant association with the occurrence of pesticide residues in vegetables (χ 2 (1) = 25.55; P = 0.001. Based on the findings of this study it is necessary to ensure continuous monitoring of pesticide residues in vegetables and training growers on good agricultural practices and best practices on vegetable handling at household level.