The application of pesticides improves crop productivity and quality by controlling insect pests. However, their excessive use negatively affects human health. The present study quantified pesticide residues in cucumber ( n = 25) and watermelon ( n = 25) from five Dar es Salaam city markets using the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) multi-residue extraction method coupled with Liquid Chromatography—Tandem Mass Spectrometry (LC-MS/MS) and assessed associated dietary health risks. Twenty-three pesticides were detected; MRL exceedances occurred in 70% of cucumber samples and 85% of watermelon samples, with carbendazim and hexaconazole being the most prevalent. The World Health Organisation classified 78% of detected pesticides as moderately to severely hazardous (Classes Ib, II, and III). Whilst adult hazard index (HI) values were below 100% (acceptable risk), children exhibited critical HI exceedances: lufenuron (682.1%) and carbendazim (137.4%) in cucumber, and acetamiprid (158.2%) in watermelon. The cumulative hazard index (HI) for cucumber samples was 1,419.8% and 401.2% for children and adults, respectively; for watermelon samples, the cumulative HI was 672.7% for children and 150.3% for adults. These findings highlight urgent gaps in pesticide regulation, enforcement, and farm-level practices in Tanzania that warrant immediate attention from policymakers and stakeholders to inform effective interventions and safeguard public health.
Kilemile et al. (Wed,) studied this question.