Punjab, riding high on pesticides
Pesticide use continues to be very high in agriculture in India, where estimated annual production losses due to pests amount to approximately US$ 42.66 million per year. Pesticides are chemical compounds that kill pests such as insects, rodents, fungi and unwanted plants (weeds) and mainly include insecticides, fungicides and herbicides. Insecticides form the highest share of total pesticide use in India.
The consumption of pesticides has risen considerably in India over the past decade - in 2014-15 it was almost 50% higher than in 2009-10. That's a 50% spike in pesticide use in a span of just 5 years.
While Punjab is the third highest consumer of pesticides after Maharashtra and Uttar Pradesh, the per hectare consumption of pesticides is the highest in Punjab followed by Haryana and Maharashtra.
Killers not just for pests
Research shows that pesticides can contaminate soil, water, the air and vegetation. In addition to killing insects or weeds that harm crops, pesticides can be toxic to birds, fish, insects and plants. Heavy pesticide use can cause a decline in beneficial microorganisms in the earth, leading to poor soil quality in the long run. Pesticide sprays can also spread rapidly through the air, posing risks to areas far away from the actual field of application. and they can reach surface water through runoff from treated plants and soil. Pesticides also pollute groundwater by leaching downwards or vertically through the soil, thus insidiously entering the food chain. Groundwater pollution due to pesticides is a serious problem because it can take many years for the contamination to dissipate.
Pesticide residues can include heavy metals that are released into the water, soil and the food chain. Studies show that long term consumption of food and water containing heavy metals can be extremely harmful to human health, causing damage to the lungs, liver, kidneys and other vital organs. It can also lead to a number of physical, muscular and neurological degenerative diseases. Repeated and long-term contact with some heavy metals or their compounds can negatively affect the endocrine and reproductive systems and eventually cause cancer.
Malwa, the pesticide hub of Punjab
The Malwa region of Punjab consumes nearly 75 percent of the total pesticides used in the state. The high use of pesticides, along with environmental and social factors, is suspected to have led to a high concentration of pesticide residues in the water, soil and food chain, threatening the health of the local population and the environment in the region.
The region has been described as India’s "cancer capital" due to the abnormally high number of cancer cases, which have increased 3-fold in the last 10 years. Studies of this region have also highlighted a sharp increase in intellectual disability and reproductive disorders, suspected to be due to pesticide use.
However, very few studies have attempted to explore the impact of pesticides on the environment, food, vegetables and water in the area and its connection with the debilitating health problems faced by the local people.
This study from two villages in Malwa region - Arnetu of Patiala District and Wallipur of Ludhiana District of Punjab - titled “Pesticides in agricultural runoffs affecting water resources: A study of Punjab (India)” published in the journal Agricultural Sciences, aimed at assessing:
- Pesticide use and its frequency among the farmers in the two villages;
- Levels of pesticide concentrations in runoff from fields, rivers and streams, and
- Health impact on the residents.
The study found that:
- Pesticide use was very high in both the villages
As high as 80 percent and 81 percent of respondents from Arnetu and Wallipur villages used pesticides in their agricultural fields.
- Use of pesticides depended on the type of crops cultivated
Farmers who cultivated wheat were spraying pesticide three times in the whole crop season. Initially, herbicides were sprayed to clear unwanted plants like climbers and creepers. Pesticides were used later to control pests and weeds.
- Pesticides led to extensive water and soil pollution
In this region, rain and irrigation caused extensive leaching or downward movement of pesticides and fertilisers through the soil and the unsaturated zone, to the groundwater. There were several other sources of water pollution as well, such as decayed animal, plant and nitrogenous wastes, industrial effluents and domestic wastewater containing detergents. High amounts of insecticides and pesticides were found in agricultural runoff in all seasons, with the highest being after the monsoon, due to increased surface runoff.
- Vegetables were saturated with dangerous levels of heavy metals from pesticides
Vegetables tested in the region along the banks of the river Ghaggar were found to be highly contaminated with harmful heavy metals such as chromium, manganese, nickel, copper, lead, cadmium and uranium. The concentrations of these heavy metals in all the vegetables samples were found to be higher than those recommended by the United States Environmental Protection Agency (US EPA), the World Health Organisation (WHO) and the Bureau of Indian Standards (BIS) guideline values.
- River water was loaded with toxic heavy metals from pesticides
The waters of river Ghaggar in the region were found to be heavily loaded with toxic heavy metals such as chromium, manganese, nickel, zinc, antimony, tin, lead, strontium, cadmium, uranium, titanium, with their concentrations being much higher than the safe limits prescribed by various organisations and agencies such as the US EPA, WHO and the BIS.
- People from the villages reported a range of health problems
This high level of pollution of the food and water sources also reflected in the poor health of local residents. The prevalence of cancer and hepatitis C was found to be very high in these villages. Spontaneous abortions and premature births were also found to be significantly higher. Stillbirths were about five times higher as compared with figures from other South Asian countries.
A large proportion of children in the area suffer from delayed developmental milestones, exhibit a blue line in their gums, have mottled teeth and presented with gastrointestinal morbidities. Although no direct association was established in the study, the results showed that heavy metal and pesticide exposure may be potential risk factors for adverse reproductive and child health outcomes.
While pesticides have been useful in increasing agricultural productivity, their hazardous impacts on the health and environment are becoming more and more obvious. Evidence from India shows that lack of information, awareness and training among farmers on safe use of pesticides, lack of effective rules and regulations and bans on dangerous pesticides, direct delivery of unapproved pesticides to farmers from the private markets further increases the risk of pesticides for the environment and health.
Better pesticide management laws and their strict implementation and encouraging use of alternative practices like organic farming and use of bio pesticides like neem and plant-based formulations like Repline, Neemark and Indene can go a long way in preventing the negative impacts of pesticides on the health and environment.
The paper can be accessed here