Pesticide use in agriculture, our health and risk on underground water in Nepal

Our family was always aware about toxic chemicals in our food because my mother who works in DADO (District Agriculture Development Office) was well known about how farmers were increasingly misusing toxic chemicals in the field. I remember her story about a farmer who friend handed her few cabbages as a gift when she visited his farm. When she was passing by his field some workers were scrapping out the outer layer of cabbage before they took it to the market. Good of her that she suggested they could utilize the outer leaves to feed animals. But her farmer friend replied instantly that the animals would die because of the pesticides without realizing that my mother had been carrying the cabbage gifts with her probably felling little lucky that day.

Few weeks ago I watched ‘SatyamebaJayate’ (watch it here) a popular TV program hosted by Amir Khan that, fairly enough, tried to expose worst effects of pesticides use. It really touched my heart when I saw poison bitten locals, trampled ecology and disoriented farmers in South of India who are still suffering EndoSulphan spray (now banned) continued for 20 years until 2000 over thousands of ha of cashwnuts crops in a rampant way from helicopter. Unfortunately even today, many pesticides that are banned in the developed countries are used in developing countries or can find a way through the weak regulatory system to farmer’s field with ease in different names. Banned or very toxic pesticides are not the only problems but the adversities posed by other generally recommended pesticides are even more dangerous because of their rampant use and their unrestricted/unregulated way to our tables with our food. The under lying terror is huge and diverse. It also stretches far from its place of origin. For example, thousands of miles away from India, England is concerned about significant doses of toxic chemical in cotton lint in clothes. Do we know the level of pesticides in our food that we import? According to Kalimati food and vegetable market development board 26% of the total arrivals of vegetables were from India on fiscal year 2010-2011 (C. Sapkota’s blog). What about the level of pesticides in food produce in our country? Forget about the ecology for the moment what about our instant health? (Click Find glimpse of crazy pesticide use cases in India- in Indian news Video 1, video 2 )

The disease of rampant pesticide use to generate some unethical money is not less in Nepalese produce. We lack sufficient research on the topic however some available research on the field is astounding. According to a research done by Nieri Giri, 2010 (master’s thesis) on Pesticide screening of soil and tea samples from Kathmanduvalley/Nepal based around 4 districts around Kathmandu

‘Out of 30 farmers interviewed, 50% stored pesticides in an unlocked room, more than 30% kept a pre-harvest interval of less than one week after pesticide application, about 50% used no safety measures during pesticide handling and application and more than 50% had health problems concerning eye irritation. The questionnaire survey also revealed that carbendazim, chlorpyrifos-methyl, parathion-methyl, imidacloprid, metalaxyl, dimethoate, omethoate and dichlorvos were the most commonly used pesticides in the studied area.’

‘The banned pesticide Ethion was found in medium and best quality tea. Also, organic tea was found to be contaminated with pesticides. Some fruits and vegetable samples were also found to be contaminated with pesticides like Ethion, Chloropyrifos, Carbendazim. Almost all the soil samples except that of Kathmandu were found to be contaminated with pesticides.’

(The number of farmers interviewed in this thesis study could be small but the results are most probably representative)

Even though direct ingestion or direct contact of pesticides are dangerous to human health pesticides are recommended to use in the field assuming strict precaution are taken. Negligence in pesticide use can cause health hazards to the farmer who spread it. But things can be more serious if the crops carry significant level of pesticides to the consumers compromising our health. Unfortunately, we are only attracted to acute health problems or causalities. Reality is, the little amount of pesticides that we probably consume every day tend to accumulate in our body fat eventually creating chronic health problems in future. Do we know if we are slow poisoning our future? Come on! food determines who we are and who we be.

The use of pesticide is continuously increasing in Nepal. A comparison table of 2 years of pesticide use in 4 district of Nepal is presented here under which shows increase in pesticide use from 2004 to 2005 (Dhakal Deepak,?) 

Comparison of different pesticides used in 4 districts (2004-2005)

Even though the pesticide use is increasing, various factors influence its effective utilization typically in developing country that may lead to reduced health, economic loss, environmental damage etc. (Fig 1.) (K Atraya, 2011). Thus, pesticide use has not necessarily been profitable to us.

Linking pesticide use to environmental degradation and marginilization

Cleaver and safe spray of pesticides are myths for workers even in developed countries with lots of precautions. In our case, farmers take risk of pesticide spray with nearly no precaution even though they know they are affected. A study (K Atraya, 2008) based on 291 house hold suggest that even though

‘there are acute health impacts of pesticide use because of the low level of the health costs , farm workers may underestimate the effects of pesticides on the human being, and thus may continue to use pesticides without any safety. The study shows that on average a person who is exposed to pesticides for 1.8 h during spraying days bears an annual cost of just Nepali rupee 144’.

However, the author also indicates biased result because chronic diseases, environmental and ecosystem health are not taken into consideration during the study which the research recommends for future study.

A study by Atraya K et al. (2011) even concludes that the sole dependence on pesticides use in Nepal is very risky in terms of economic benefit and may incur unintended problems. The same study well describes about the success of Integrated Pest Management (IPM) in development countries including Nepal. The study finally suggests that programs like community IPM along with education and training would be a better solution for Nepal.

Development of agriculture should be based on solid ground. Agriculture based on imported and expensive pesticides makes future of agriculture more fragile. In addition to that the potential risks that pesticides incur such as chronic human health and dreadful long lasting environmental consequences should alert government and policy makers. It is important for us to act and think differently so that we can reduce the use and import less pesticide. IPM makes sense in our context. IPM could help not only to reduce pesticide use and cost of agriculture practices but also the risk of hazardous pressure in soil and environment. Maintenance of environment and ecology will have significant effect in our well being and sustainability of our system. 

Let’s get to know one of the dreadful effects of pesticide that could potentially crush our society.  

The Ground Water Risk

There is potential risk of pesticide contamination in ground water in Nepal due to haphazard use of pesticide. Area with sandy soil is at higher risk of such contamination compared to clayey soil due to easy water percolation. Earlier it was thought that the pesticides that are accidently spilled in field or higher doses of pesticides that are sprayed in the field will never reach ground water however, increasing evidence suggest that pesticides from field can also reach ground water. It will take years before it appears in deep ground water because it takes long time for water to percolate through soil. They will either go to the river system or appear in wells. While in shallow wells seeped chemical may quickly appear and possibly cleared away in couple of years after treatments but in deep wells it will appear after very long time (because of percolation time in soil) but cannot easily be treated.

However, very simple carelessness during tank filling, chemical mixing, spraying, re-filling, hand or utensil washing, tank emptying and cleaning, disposal of pesticides especially near the ground water sources like tube well, well, deep boring etc. will pose serious threat to instant ground water contamination. Strict measures are taken in developed country and laws are highly regulated considering its sensitivity. For example, in Denmark using mobile phone is prohibited while handling chemicals because farmers may accidentally spill chemicals in field increasing the risk of chemical percolation to underground water.

Picture showing estimated water movement in soil

Thus even accidental spell of pesticides poses dangerous threat to ground water contamination. If by chance, ground water is contaminated it will be a chronic problem. It will take years before such chemicals are degraded because it remains away from active microbial zone. There is very less chance that any government rule could regulate such mishaps in Nepal but an aware community on ground water contamination and possible chronic problem may encourage to regulate such activity in local condition.

Author Gunadhish Khanal is MSc in Agro-environmental management


*Comments, questions and suggestions are welcomed

References:

1. Atreya, K. 2008. Health costs from short-term exposure to pesticides in Nepal. Social science & medicine 67(4): 511-9Available at http://www.ncbi.nlm.nih.gov/pubmed/18514373 (verified 9 July 2012).
2. Atreya, K., B. Sitaula, and F. Johnsen. 2011. Continuing Issues in the Limitations of Pesticide Use in Developing Countries. Journal of Agricultural 24(1): 49-62Available at http://www.springerlink.com/index/10.1007/s10806-010-9243-9 (verified 9 July 2012).
3. Atreya, K. 2008. Probabilistic assessment of acute health symptoms related to pesticide use under intensified Nepalese agriculture. International Journal of Environmental Health 18(3): 187-208Available at http://www.ncbi.nlm.nih.gov/pubmed/18569147 (verified 9 July 2012).

Some other video sources:

1. Watch Panjab Chemicals Killing farmers
2. Watch this presentation to understand pesticide and its bad effects. 
3. Watch a nice documentary on pesticide use on cotton field in India
4. Watch Satyameba Jayete on pesticides