Pesticides in Agricultural Run Offs Affecting Water Resources: A Study of Punjab (India)

Abstract

Background: The pesticides belong to a category of chemicals used worldwide as herbicides, insecticides, fungicides, rodenticides, nematicides, and plant growth regulators in order to control weeds, pests and diseases in crops as well as for health care of humans and animals. The positive aspect of pesticide use renders enhanced crop/food productivity and drastic reduction of vector-borne diseases. On the other hand, excess use of fertilizers threatens the groundwater and surface water on a large scale. Agricultural runoff is surface water leaving cultivated fields as a result of receiving water in excess of the infiltration rate of the soil. Pesticides can enter water through surface runoff or through leaching. These two fundamental processes are linked to the earth’s hydrologic cycle. Methodology : Data for the present study were collected from two villages, Arnetu of Patiala District and Wallipur of Ludhiana District of Punjab, India, from the year 2017 to 2018. Data on the frequency of pesticide use, demographic profile, and the concentration of heavy metals in edible vegetables were collected by using structured schedule, case study, and in-depth interview from a total of 250 respondents. Elemental analysis of vegetable samples was carried out with the help of Energy Dispersive X-Ray Florescence (EDXRF). Objectives: a) assessment of pesticide use and its frequency among the farmers of the studied areas; b) to ascertain potential health risk of pesticide concentrations in runoff from field-sized agricultural watersheds and in rivers and streams and its impact on the residents of the field area ( Figure 1 & Figure 2 ); c) to collect cases of effected families. Results: It was reported that 80% and 81% of respondents from Arnetu and Wallipur village respectively used pesticide in agricultural fields. The frequency of pesticide use was 60% of the respondents from Arnetu and 70% from Wallipur village reported that their use of pesticides depends upon the type of crops they have cultivated. The area observed leaching (vertical downward displacement of pesticides through the soil profile and the unsaturated zone, and finally to groundwater) of fertilizers and pesticides frequently occurring due to rain or due to irrigation water. It had an indirect impact on the health of the residents. The results of the analytical analysis of vegetables suggested that all the vegetables. Were contaminated maximally by some of the heavy metals. Chromium (Cr), Manganese (Mn), Nickel (Ni), Copper (Cu), Lead (Pb), Cadmium (Cd) and Uranium (U) had been found to be present in higher amounts. The concentrations of these heavy metals in all the vegetable samples were higher than the (US EPA/IS/WHO/BIS) guideline values. The prevalence of cancer and Hepatitis C was found in Wallipur village where 81% respondents supported pesticide application in their field. Conclusions: Thus, the present study reflects the adverse health effects of the pesticides’ use on groundwater which in turn indirectly is affecting human health. The entire realm of pesticide use reveals a certain un-certainty of situations in which the residents of studied areas are undergoing life-long exposures.