Organophosphorus pesticide residues in tomatoes: A case of Mlali and Doma Wards in Mvomero district, Morogoro

Abstract

Extensive pesticide use poses a significant challenge to Tanzania's horticulture industry, particularly affecting the leading tomato producer, the Morogoro region. This study focused on assessing organophosphorus pesticide residues in tomatoes from Mlali and Doma divisions in the Mvomero district of Morogoro. A total of 40 samples were collected from both farms and markets for analysis, utilizing Gas Chromatography with Mass Spectrometry (GC-MS) for extract analysis. Statistical Analysis Software (SAS) Version 9.1 was employed for data analysis. The study identified six organophosphorus pesticides, with concentrations in the following order: pirimiphos methyl > diazinon > fenitrothion > dimethoate > profenofos > chlorpyrifos. Pirimiphos methyl levels ranged from 3.32±0.03 to 9.53±0.05 µg/kg in Mlali samples and 0.20±0.01 to 6.33±0.03 µg/ kg in Doma samples. Chlorpyrifos was detected in the lowest concentrations across all samples. Interestingly, higher pesticide levels were found in market samples compared to those from farms, suggesting potential misuse post-harvest and during distribution. This misuse could have severe consequences for tomato consumers, including both carcinogenic and non-carcinogenic effects. The study underscores the importance of educating farmers on the proper use of pesticides and the potential adverse effects resulting from their misuse. Addressing this issue is crucial for ensuring the safety of tomatoes in the market and protecting consumers from harmful effects associated with pesticide residues.