Crop wise, in India the consumption of pesticides are found highest in cotton i.e. around 37%, followed by paddy (20%), while the vegetable consumes about 9% pesticide residues. Farmers often spray hazardous insecticides like organophosphates and organochlorine up to five to six times in one cropping season while only two applications may be sufficient. A study was thus undertaken to analyze the contamination by pesticide in groundwater samples collected from tubewells installed in the farm fields of vegetable, rice and cotton growing areas.
Groundwater samples collected from vegetable growing areas were found contaminated with 31.3% organochlorine and 19.4% samples with organophosphorous pesticides above MRL value. All the synthetic pyrethroids analyzed were found below MRL value.
Groundwater samples collected from rice growing area and the variety grown there was 11/21. Samples were found contaminated with 24% by organochlorine pesticides, 23.4% by organophosphorous pesticides and 20.8% by synthetic pyrethroids above MRL value.
Samples collected from cotton growing area 59% were found contaminated with organochlorine pesticide, 45.3% by organophosphorous pesticide and 29.2% by synthetic pyrethroids residues which were above MRL value.
Diseases caused by organochlorine pesticides are loss of sensation around the mouth, hypersensitivity to light, sound, tremors, nausea, vomiting, nervousness etc.
The adverse health effects caused by organophosphorous are increased salivation, perspiration, narrowing of the pupils, nausea, diarrhea and fatigue. Pyrethroids can cause an allergic skin response, and cause cancer, reproductive or developmental effects, or endocrine system effects.
There is need of proper extension services to educate farmers about the judicious use of new molecules of pesticides along with Integrated Pest Management approach to avoid contamination of water resources.