Pesticide residues analysis of three vegetable crops for urban consumers in Benin - human and environmental consequences of abuse and misuse of synthetic pesticides.

摘要

Urban and peri-urban (UPU) horticulture provides an increasingly important source of income in African countries. The potential of UPU gardening is severely undermined by a number of production constraints. Recent field diagnoses in Benin identified severe pest problems and revealed alarming pesticide practices in the UPU areas. Several major pest problems are direct consequences of pesticide abuse that (1) destroys the biodiversity required for natural/biological pest control, (2) causes pesticide resistance and pest resurgence and (3) poses human and environmental hazards. Increasing pesticide use among vegetable producers in UPU gardens in Benin led to the initiation of the pilot project "Pesticide residues analysis of three vegetable crops for urban consumers in Benin". A total of 92 samples of tomatoes, carrots and leaves of African eggplant ("gboma") were collected in November 2010 at different markets in Benin. The samples were comminuted in Benin and sent frozen to Norway for analysis of possible pesticide residues. Two multi-methods covering 293 pesticides including some metabolites were used for the analysis. Residues were detected in 20 samples, resulting in 41 findings of different pesticides and/or metabolites. Gboma leaves contained the highest number of residues and also the highest concentrations of pesticides. One sample had a very high content of dimethoate and omethoate (sum 8.1 mg/kg). Consumption of these leaves may represent a health risk, as both the acceptable daily intake (ADI) and acute reference dose (ARfD) were far exceeded. Few residues and low concentrations were found in the carrot and tomato samples. Internationally banned pesticides are commonly used in UPU vegetable production in Africa. The link between agriculture, environment and health is evident. Despite this, consumer consumption of pesticide residues through contaminated products receives little attention.