Time to read: 8 min

Every day, food on our table is laced with toxic pesticide residue! We hear cases of acute pesticide poisoning now and then… and then we wonder is it really happening with me? Should I be concerned about the pesticides in my plate…well, it’s the time to find out…Let’s understand the pesticides, how they harm us and are we really getting exposed to them every day? If yes, then what can we do to minimize its ill effects.

What are pesticides?

Pesticides are basically chemicals sprayed on plants to save them from various kinds of pests. Depending upon its target, pesticides can be classified into insecticides, herbicides, rodenticides, molluscicides, nematicides, plant growth regulators and others. Pesticides are mostly used, and most of the time overused, to protect plants from pests and to increase crop yield and productivity. Of course, the use of pesticides improves the quality of the crops and generates more income for the farmer, but the downside of using pesticides cannot be ignored.

India is the largest producer of pesticides in Asia and ranks 12th in the world for the application of pesticides. If you want to look at the state-wise data, Andhra Pradesh consumes the highest amount of pesticides followed by Panjab and Maharashtra.

Since ours is a tropical country, our pesticide consumption pattern is different from the world. Almost 76% of pesticide use is attributed to insecticides in India. Unfortunately, 95% of sprayed insecticides reach other species and other places such as air, water, and soil.

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Use of pesticides in India VS the world ( Aktar et al,2009)

 

Among edible crops, Highest amount is used on rice followed by wheat and pulses, then vegetables and other plantations. Most commonly used pesticides on cereals include organophosphates, carbamate, synthetic pyrethroids, and insect growth regulators, both in storages and prior to shipment in order to prevent insect infestation. Vegetables are usually sprayed with sulfur, endosulfan, mancozeb, phorate, methyl parathion, monocrotophos, cypermethrin, isoproturon, chlorpyrifos, malathion, carbendazim, butachlor, quinalphos, copper oxychloride, and dichlorvos.

What is the health risk of pesticide exposure?

Many ill effects of pesticides are documented in the literature. Many pesticides work as neurotoxins for their intended targets. They act on their nervous system to kill them. Unfortunately, other animals or even sometimes humans share similar biochemistry with lower primates and can become unintended victims. Though regulatory bodies see to it that maximum limits are placed on the food residue, these pesticides can bioaccumulate due to low but chronic exposure and then the ill effects become evident. Let’s see the case of farmworkers in working in Madhya Pradesh, In 2018 researchers reported that 248 farmworkers exposed to pesticides over a long period of time, were having many neurological problems as listed in the graph. More than 50% were experiencing muscle pain, headache, and dizziness.

Percentage of farmworkers suffering from neurological problems (Kori et al, 2018)

 

Apart from neurological effects, exposure to pesticides can cause respiratory, gastrointestinal and reproductive problems. Consuming fruits and vegetables with high pesticide residue content may be associated with infertility, lower sperm count, difficulty in conceiving, spontaneous abortion and premature birth. Pesticide molecules even at very low doses mimic our body hormones and interferes with the endocrine system. So, the effects can also be observed in the form of disturbed body metabolism, sleep cycle, and the body’s stress response. Pesticides may weaken our immune system. The compromised immune system increases our susceptibility to infectious diseases. Pesticide exposure is also linked with leukemia.

Chronic exposure to pesticides is significantly associated with tumor development. Blood tests of cancer patients showed higher organochlorine pesticide residue levels.

 

Imagine that the effect of exposure is so grave in adults what would be the case with growing children?

Why children are at more risk?

Children and pregnant women fall under the high-risk category. Children are more susceptible to the harmful effects of pesticides because of their still developing and immature organ systems. According to UNICEF, the Same amount of pesticide is 10 times toxic to children than adults due to the small size of kidneys and liver. UNICEF has summarized the kind of effect pesticides would have in children in below infographic.

Courtesy: UNICEF

Pesticides disturb the mental and physiological growth of children. As children eat more food and drink more water per unit of body weight, they have higher pesticide exposure. Pesticide exposure for a growing fetus can cause irreversible damage to the brain and other organ systems. It also delays the normal process of development. Public health specialists are linking pesticides with many neurodevelopmental problems such as learning disabilities to ADHD and autism.

Children are at higher risk of developing cancer due to the carcinogens present in pesticide residue. Studies show that pesticide exposure during pregnancy and throughout childhood increase the risk of cancer among children. The report shows that almost 50000 children in Kerala are now battling with cancer.

Should we really worry about the pesticides?

Now that we have gone through all the harmful effects that pesticides can have on ourselves and our children, still…you might be thinking, is it affecting me? The answer is, unfortunately, Yes. We need to worry about the amount of pesticide we are getting exposed to on a daily basis. Almost one-third of pesticide poisoning cases in the world occur in India. In 2017, 40 farmers died and 700 were hospitalized due to pesticide poisoning. In Bihar (2013), 23 children died due to the consumption of pesticide-contaminated mid-day meal. A report published in the Times of India also revealed that women residing in Gangetic plains had higher incidences of cancer than the urban population due to long term pesticide exposure.

A group of researchers in Delhi in 2006 found that almost all the villagers in certain villages of Panjab had high serum pesticide levels. Incidences of cancer were also very high in the same region due to prolonged pesticide exposure. These are the examples of cases where the high-risk population was involved such as farmers, people staying in rural areas.

People staying in urban areas are also at risk of chronic low dose pesticide exposure due to the toxic residue that remains on the food. American Academy of Pediatrics highlights that pesticide residue on food is the major route for children to get exposed to pesticides.

 

A ‘pesticide residue’ is the pesticide or the metabolic products of pesticides that remain in the produce after they are applied to crops. Most of these metabolites can accumulate in the body over a period of time and can cause serious damage. A research study done by Gupta in 2004 revealed that 51% of Indian food commodities were contaminated by pesticides. 35% of contaminated samples had pesticide levels above the maximum residue limit specified by WHO and FAO (Charan, et al, 2010). A review study was conducted by N. Nishant and R Upadhyay in 2016 on pesticide residues in vegetable crops reveled that okra, brinjal, lettuce, tomato, and cucumber are mostly found contaminated by pesticide compounds such as Chlorpyrifos, Monocrotophos, Endosulfan, DDT and Lindane, etc. These toxic pesticide residues can have adverse health effects on the human body. Unfortunately, these bioaccumulate pesticides are not only a threat to us but also to the future generation.

When maternal blood and cord blood samples of mothers residing in north India were analyzed, organochlorine pesticide residue was detected. The study claimed that the transfer rate of these residues from mother to newborn is almost 60 to 70%. Such a high rate of transfer is a serious cause of concern. Pesticide residues were also observed in the breast milk samples. In Punjab, a few newborn baby’s daily pesticide intakes were found to be above the tolerable daily intake limits specified by FAO /WHO.

Recent research conducted in Hyderabad by National Institute of Nutrition detected pesticide metabolites in the urine samples of 6 to 15-year-old children.

All these research studies confirm the fact that pesticides and very much present in our food environment and we have to take urgent steps to minimize its exposure.

 

Measures to avoid exposure to pesticides

At home level, we mostly try to reduce the pesticide residue by washing, peeling, soaking, etc. Washing is the most commonly used method to reduce pesticide residue. Researchers tried to observe the effect of tap water washing on the efficiency of pesticide residue removal. Ten commonly found pesticide residue on spinach and cucumber were studied. The result showed that 5 mins of tap water washing could only remove 9 to 24 % of pesticide residues in cucumber. Whereas in the case of spinach, the effectiveness of removing pesticide residue was limited to 4 to 27%. Thus, our home-based methods can only remove ¼ of the pesticide residue present on the outermost layer of the cereals, fruits, and vegetables.

Washing fruits and vegetables with salted water is a good idea as it is more effective than tap water. However, research showed that washing with salted water was effective only when the vegetables were washed for more than 15 minutes. Considering our busy routine lives, this looks like an impractical solution. Also, In some cases, depending upon the chemical nature of the pesticides and food. Some minute amounts also may get absorbed in the flesh of the fruit, which is impossible to remove.

Another alternative is to choose food products that are grown by organic farming. Organic farming ensures that no pesticides are used during crop cultivation. They are grown by natural methods. A Meta-analysis of 343 research articles revealed that organic products have higher antioxidant content and lower incidences of pesticide residue than non – organic products.

Are commercially available organic products really organic?

Organic products are costlier compared to their regular counterparts, which naturally raises the question about their authenticity. Are we paying for the right product? How to make sure that the products that we buy are really free of pesticides? Buying certified organic products is a way to ensure is that products are really 100% organic. Products that are approved by USDA follow stringent rules and regulations. These regulations monitor soil quality, crop raising practices, pest and weed control and use of additives. The soil on which certified organic food is grown is kept free from synthetic chemical fertilizers and pesticides for three years. It makes sure that there are no traces of chemicals in the soil that may find their way in the food. The crops are raised only by natural methods using physical, mechanical and biological based farming methods.

Consuming certified organic food is a reliable way to minimize pesticide exposure through foods. It helps you to follow a healthy nutritious living without trading it off with food safety.

Have a safe and healthy life!

References:

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