False claims about the herbicide glyphosate

By Prof. Chandre Dharmawardana

I was amazed to find myself reading shockingly irresponsible headlines over the recent past which claim that the weed-killer glyphosate has destroyed health in the plantations sector, particularly given that at present there has yet to be reported a single credible case of glyphosate causing harm to the health of a single person in the plantation industry, let alone the wider agriculture sector in Sri Lanka or anywhere else in the world. 

There are over a billion farmers and at least half a billion farms in the world. Over 90% of these farms have been using some form of glyphosate for eliminating weeds, for many decades. However, except for two or three maverick law suits (one or two out of a billion!) brought against Monsanto by litigious American or French farmers, no confirmed cases of any chronic or acute illnesses that can be connected with glyphosate have been identified. None of the courts have concluded that glyphosate definitely caused an illness. 

The number of cases who can become seriously ill due to eating peanuts in the USA is about 250,000 and this is very much less than the two or three cases where people have claimed illness from glyphosate, and none has been confirmed. Nevertheless, people become “heroic” and raise fear against glyphosate which has become a surrogate for attacking a big multinational – namely Monsanto! 

In unison with the experts of the World Health Organization, the Food and Agriculture Organization, the joint committee on pesticide residues, and many scientific societies of the world  (including the National Academy of Sciences, Sri Lanka), I wish to state categorically that there is no basis whatsoever for banning glyphosate in Sri Lanka as it is not a health risk. 

The real health risks are from the polluted air from motor traffic, particulate dust, polluted soil from rotting garbage, tropical vectors like dengue and other mosquitoes, and a lack of clean drinking water for many individuals in the dry zone. Scientists have now proven conclusively that the kidney disease epidemic in the Rajarata is caused by drinking well water containing an excess of fluoride and magnesium that come to the water from the soil. It has disappointed many that it has nothing to do with glyphosate and other agrochemicals.

Any person attempting to level criticism at the use of glyphosate should also keep in mind that this prior to the ongoing, insensible ban, this weed killer has been used for quite some time in Sri Lanka, and there was absolutely no such health problems reported during the last quarter century when the substance had been extensively. In fact, the problem is that the plantations have become unhealthy due to weeds that have taken over, just as garbage has taken over the cities.

I have followed the subject of environmental toxins for many years now, starting from my early involvement in food science and environmental chemistry in the 1970s, when I was instrumental in setting up those disciplines of study at the Sri Jayawardenapura University.  Initially, glyphosate was known for its capacity to immobilise and remove heavy metals and binding them (“chelating them”, in the jargon of the chemist). In fact, even today, toxic soils containing heavy metal toxins like cadmium, mercury, and lead, can be rendered safe by application of glyphosate to the soil, as demonstrated even recently by Chinese scientists who showed that such contaminated soil which prevented earth worms from living in them began to have thriving colonies of earth worms when treated with glyphosate. Glyphosate is not toxic but even beneficial when used properly. Farmers can use it safely, without goggles, gloves, etc. 

Glyphosate is not used for cleaning up toxins from the soil; instead, its major use is to kill weeds. Its capacity to kill weeds (“flora”) without harming the fauna was discovered in the 1970s, and glyphosate soon became the most widely used herbicide in the world. The reason for its popularity is its effectiveness and the fact that it is environmental harmless in comparison to other alternatives including manual weeding and tilling. 

According to World Bank data, countries like New Zealand use up to 35 times more agrochemicals like glyphosate compared to poor countries like Sri Lanka; 50 times more than a country like Nicaragua. Interestingly, various chronic diseases are found in the low users of these agrochemicals, while the high users are remarkably free of chronic disease! 

This anti-correlation between the two is simply because the countries that use large amounts of agro-chemicals are in fact rich countries with a high standard of living, while the countries which use low amounts of agro-chemicals are in fact too poor to afford to buy agrochemicals and also to provide a high standard of living or even clean drinking water to the inhabitants.

Sri Lanka falls to that category of countries where many of its citizens have been settled in “colonisation schemes” without providing them even the bare needs like clean drinking water.  The early settlers of the Mahaweli and Padaviya schemes could get their drinking water from the tanks, rivers and irrigation canals of the agricultural schemes. Latecomers had to settle further away from such running water, and they dug their own household wells for drinking water, just as they had done in their wet zone villages where they originated from – that they left due to population pressure in the south. 

But little did the settlers know that the Rajarata soils are rich in fluoride. This fact was known to geologists who had already noticed the onset of the illness known as fluorosis in people who lived in the Rajarata area and drank well water. The settlers knew that the water tasted slightly brackish (“kivul”) but they soon got used to that. The brackishness was attribute to the water being “hard”, i.e., containing calcium and magnesium salts in excess of what is found elsewhere. Fluoride itself cannot be detected by taste.

However, although there were virtually no people in the Rajarata in the 1960s due to malaria, the eradication of malaria and the implementation of Mahaweli and other projects increased the population significantly by the 1980s. A new kind of kidney disease without the usual accompanying symptoms (of diabetes and hypertension) was detected in the early 1990s, but still only in small numbers.  By the time the disease manifested itself, the patient’s kidneys would be irreparably damaged over the years, but this was unknown to the victim. This disease was named chronic kidney disease of unknown origin (CKDu). Even today, the disease can be detected only via laboratory tests of urine and blood, and early detection is a challenge. If the disease existed in ancient times, it would certainly not have been identified, and deaths would have been ascribed to occult forces, divine wrath, fate, or even snake bite, as is done even today by rural people.

When CKDu turned into a localised mini-epidemic, kidney experts and scientists at first thought that the disease may be due to Cadmium, a well-known kidney toxin found in agricultural soils. But chemical analysis of the water and food by many independent scientific groups and also by a WHO sponsored team showed that there are no significant concentrations of such metal toxins. They also showed that hardly any glyphosate was found in the biopsies of CKDu patients.  

Glyphosate is deemed the culprit but it is not even found in the location of the crime!

And yet, a number of anti-glyphosate militants as well as a lady who claimed to have psychic powers began to claim that arsenic linked to calcium (from the hard water) and glyphosate acting together were the cause of the disease. This was only stated as a “hypothesis”, but sold to the public as a proven fact, even though there is not one iota of evidence for it. The Government, in embracing unproven claims of anti-science pressure groups has banned glyphosate. This is bringing the tea, vegetables and other plantation industries to their knees. The “traditional agriculture” lobby is ecstatic, but this ecstasy will soon wilt when the agriculture sector of the country collapses irreparably, like the kidneys of the CKDu patients who have no clean water to drink.