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In the regions of Kérou and Péhunco in northern Benin, vegetable crops can be found within cotton fields, exposing consumers to worrying health risks. This paper therefore aims to assess the level of contamination of edible leaves by the pesticides used and associated metals. A total of ten samples of each edible leaf were collected and analyzed in a laboratory. After sample preparation, heavy metals were identified by atomic absorption spectrometry, while active pesticide substances were investigated using chromatography combined with spectrometry. The results indicate that the vegetable varieties (okra, sorrel leaves, nightshade, bean leaves) have lead concentrations between 0.07 mg/kg and 0.53 mg/kg. The highest copper content was found in nightshade (6.94 mg/kg ± 1.59) and the lowest in sorrel leaves (1.13 mg/kg ± 0.08). The highest zinc content (19.7 mg/kg ± 8.04) was found in nightshade and the lowest in sorrel leaves (6.27 mg/kg ± 0.68). Bean leaves had a high concentration of cypermethrin (39.4 mg/kg ± 2.21), while okra had a low concentration (9.80 mg/kg ± 1.73). The highest deltamethrin content was found in sorrel leaves (32.8 mg/kg ± 1.85), and the highest glyphosate content (2.92 mg/kg ± 0.28) was found in bean leaves. These results show that almost all vegetables are contaminated with lead, copper, zinc, cypermethrin, deltamethrin, and glyphosate. This could have consequences for the health of the consumers (occurrence of diseases) of these vegetables, especially those which have a high content (above the permitted threshold) of these chemicals and toxic metals. In view of these findings, farms should be zoned according to each type of crop to avoid contamination of food crops.