Herbicides vis-a-vis other pesticides: An overview on use and potential hazards Sharma Neelam*,2, Yaduraju N.T.1,2, Rana S.S.2 2CSK Himachal Pradesh Krishi Vishvavidyalaya, Palampur, Himachal Pradesh, 176 062 1Former Director, Directorate of Weed Research, Jabalpur, Madhya Pradesh, 482 004 *Email: sharma_neelam29@rediffmail.com
Abstract Modern agriculture depends on the four main factors viz: seed, water, fertilizers and pesticides. The total number of pests attacking major crops has increased significantly from 1940s. Therefore, the demand of pesticides especially herbicides in agriculture is increasing. Farmers are facing shortages of labour for hand weeding crop fields as people are moving to urban from rural areas. Herbicides are cheaper and more readily available than labour for hand weeding. This review article focuses on the status of using herbicides vis a vis other pesticides and their uses and potential hazards. All pesticides must be toxic to be effective against the pests they are intended to control. Because of being toxic, pesticides are potentially hazardous to humans, animals, other organisms, and the environment. Therefore, users of the pesticides must understand the relative toxicity and potential health effects of the products they use. Pesticides are classified based on the oral and dermal lethal dose, 50% values (to the rat) of the active principles. Globally, 35% of the 158 insecticides fall under extremely hazardous and highly hazardous categories, compared to only about 4% in case of herbicides. Under the slightly hazardous group, the number of herbicides is two times higher as compared to insecticides. The number of herbicides that are unlikely to present acute hazard is as much as 37.1% of the total as compared to 12.6% insecticides. Thus, herbicides as a pesticide category are safer or less hazardous than other pesticides especially insecticides. But it is not intended to give clear chit to herbicides because the ultimate toxicity depends on the formulation. The formulation of pesticides may be thousand times more toxic than their active principles. Thus, there is need to set maximum residue limits (MRLs) based on formulation rather than on the basis of active principles. Top Keywords Herbicide, Insecticides, Pesticides, Uses, Hazards. Top |