Insecticide Residues in Soil, Water, and Eggplant Fruits and Farmers’ Health Effects Due to Exposure to Pesticides

The study design is a cross sectional of randomly selected eggplant farms in Sta. Maria, Pangasinan. Soil, water, and eggplant fruits were collected and subjected to gas chromatography (Shimadzu) analysis for multi-pesticide residues.

Farmers from Sta. Maria, Pangasinan were found to be applying a broad spectrum of insecticides on their eggplant crop. Soil samples from 11 (about 42 %) out of the 26 farms tested positive for insecticide residues, six of which from four farms exceeded the acceptable maximum residue limit. These residues were profenofos, triazophos, chlorpyrifos, cypermethrin, and malathion. No insecticide residues were detected from water samples taken from the 26 farms. Cypermethrin and chlorpyrifos were the insecticide residues detected in eggplant fruit samples. A maximum of 20 % of the eggplant samples tested positive for insecticide residues. In the eggplant fruit study, all farmers have been using Prevathon^® for 24 years at a rate of 10 ml/application, and Malathion^® for 25 years at about 16.5 ml/application, respectively equivalent to 0.24 liter-years and 0.413 liter-years of exposure. Similarly, to the findings in the soil and water study, although Brodan^® and Magnum^® were not prevalently applied, the farmers’ liter-years of exposure to these insecticides, and their active ingredients, were highest at about 18.92 and 10.0, respectively. The farmers and farm workers in the soil and water study reported experiencing itchiness of the skin (63.8 %), redness of the eyes (29.3 %), muscle pains (27.6 %), and headaches (27.6 %), as being related to their pesticide exposure.

In summary, a maximum of 20 % of the eggplant samples tested positive for insecticide residues at any one stage of sampling done. The farmers and farm workers also reported of pesticide-related illnesses but none of them sought any medical attention. Intervention to reduce the farmers’ pesticide exposure can focus on the risk factors identified, primarily the toxicity of pesticides used, the unsafe application practices, and the adverse health effects of pesticide exposure.