Potentially toxic metal contents in common insecticides and fungicides sold in Bangladeshi marketplaces and their burden to farm soils

The objectives of this research were to measure the contents of potentially toxic metals in popular insecticides and fungicides that are sold in several Bangladeshi marketplaces and to evaluate their loads on farmlands. The contents of As, Cu, Fe, and Mn in insecticide and fungicide samples varied from below detectable limit (bdl)‒47.78, 47.93‒495.9, 272.1‒3218, and 9.54‒203.0 µg g⁻¹ and bdl‒2.14, 52.50‒979.4, 79.67‒3718, and 38.42‒9721 µg g⁻¹, respectively. The study revealed that the concentration of potentially toxic metals varied significantly among the same groups of insecticides and fungicides, which might be due to the use of low-quality ingredients during the manufacturing of pesticides. Comparative results showed that the concentrations of As and Cu in insecticides and Cu and Fe in fungicides sold in Bangladeshi markets were significantly greater than those of other nations. The study results suggest that fungicides contributed more potentially toxic metals to the nation's farm soils than insecticides did. Additionally, the mean total metal burden in fields increased in the following order: As < Cu < Fe < Mn. In contrast, the mean relative abundance load of metals in insecticides was higher for As followed by Cu, whereas in fungicides, the sequence was Cu > Mn > As > Fe. The PCA results indicated that the use of fungicides had the most significant effect on the soil burden of Cu, Fe, and Mn, as well as the total potentially toxic metals burden. The study concluded by recommending that pesticide manufacturing companies must obtain certification to verify the quality of their products.