Impacts of Pesticides and Fertilizers on Soil, Tail Water and Groundwater in Three Vegetable Producing Areas in the Cordillera Region, Northern Philippines

Abstract

The study focused on the impacts of pesticides and fertilizers on soil and water in three vegetable producing areas in the Cordillera region in the northern central part of the Philippines. Three major vegetable producing communities were selected as study sites with seventy five (75) key informants interviewed. Soil and water samples were obtained to determine the extent of soil and water contamination with pesticides and fertilizers. There was a high level of awareness on the negative impacts of commercial pesticides and fertilizers on soil, water and human health but awareness did not influence the way farmers utilize pesticides and dispose of empty bottles/containers of pesticides after use. Soil samples from Balili, Mankayan, Benguet and Sadsadan, Mt. Province contain variable amounts of pesticide residues in the top 15 centimeter soil surface. The residues detected were: chlorpyrifos, profenofos, cyhalothrin, cypermethrin and fenvalerate. Chlorpyrifos was found in one soil sample in Sadsadan above the Limit of Determination. Similarly, chlorpyrifos, cypermethrin and fenvalerate were found in two soil samples in Balili higher than the limit of determination.  No pesticide residue was found in all soil samples obtained from the inner 200 centimeter soil depth.  Soils in the garden sites of Tinoc, Ifugao were still pesticide free. Water samples in all the sites contain no pesticide residues but found to contain high levels of coliform bacteria. Pesticide contamination of soil and water was not as severe as anticipated but rather it is the presence of coliform bacteria severely contaminating water bodies in the area. Natural springs unspoiled by human population are still clean and potable. Nitrate levels in soil and water is low but showed some signs of building up due to the continuous application of fertilizers. Hospital records showed no reported cases of pesticide poisoning due to improper handling. However, there were cases of intentional ingestion of pesticides for purposes of committing suicides. Respiratory diseases top the list of the ten leading causes of morbidity in all three study sites. The study site in Tinoc was affected by frequent cases of diarrhea especially during the rainy months.