by Chandre Dharmawardana

Roundup is one of the commercial names of a glyphosate-based herbicide (“weedkiller”). Glyphosate is manufactured mainly in China, though it originated in the USA. The government has just announced that the ill-conceived ban on glyphosate – an essentially harmless herbicide – has been relaxed to allow the tea industry to use it, thus averting a looming agricultural and socio-economic disaster. Fortunately, the government is ready to listen to scientific opinion and correct erroneous decisions. A group of scientists that included seven past Director Generals of agriculture, physicians, scientists and University Professors advised the government to relax the ban as there was no scientific basis for it. The present writer was also a signatory to that appeal. The government should lift the ban completely, allowing agriculture to thrive, noting that no other country has banned glyphosate so far, and that all mainstream scientific opinion unanimously hold that glyphosate is a very safe herbicide, with no danger of causing cancer, kidney disease or any other diseases, when used in agriculture.

What people say.

Let us look at what the critics who responded to the Lankaweb report (http://www.lankaweb.com/news/items/2016/09/20/sri-lanka-to-relax-glyphosate-weedicide-ban-report/) had to say.

One writer begins with the ex-cathedra statement:

“Almost all Herbicides (Weedicides) are harmful to people. The chemicals can be absorbed through the SKIN. Particularly in the case of paddy farmers who work with their feet in the waters of the paddy fields are susceptible to the poisons in the herbicides dissolved in water. Also, if paddy field workers put their hands into the waters in the paddy fields, the same thing can happen“.

The banality and danger of this kind of statement is that it sounds “true” to the uninitiated It is like saying that the sun goes round the earth, because it is evident to everybody.

When the writer says “paddy farmers … are susceptible to the poisons in the herbicides dissolved in water”, he is completely certain that there are poisons and herbicides in the water of Sri Lanka’s paddy lands. But in reality there is not one iota of evidence for the presence of glyphosate in the water! Also, there is overwhelming evidence that there can be no detectable glyphosate in the water. Most paddy-field waters, irrigation canal waters or tank water contain algae. But glyphosate, even in microgram quantities is deadly to algae. The glyphosate will be rapidly used up in fighting the algae. If there is any residual algae, there can be no residual glyphosate. So the presence of algae proves the non-existence of glyphosate.

How do we correct the false statement “Almost all Herbicides (“weedicides”) are harmful to people”? In fact,we have to say that ALL SUBSTANCES, including water, are harmful to people if the maximum allowed intake (MAI) is exceeded. On the other hand, if the amount consumed is less than the MAI, it may even be beneficial to a person. Thus vitamin A is a poison if too much of it is taken (e.g., several tablets instead of the recommended one tablet per day). But if the right dosage is taken it is beneficial for you.

All substances have a MAI value. Thus water has a MAI of six liters for consuming on one sitting for a person of about 70 kg body weight. If you exceed that, even water becomes a poison and people have died of water toxicity. If you take a saturated solution of soap, a tiny tiny amount of it will enter the body through the skin but this is of no importance. More will enter if you have cuts on your skin. Even then it is of little importance. But if you swallow a piece of soap, say even 20 grams of it, you will begin to see immediate toxic effects. But soap is consumed by us in much smaller amounts (micro-gram quantities) because we use soap-like detergents to wash dishes, wash the hands and face, in bathing, and in mouth washes and even in food saponifiers. But as long as the total intake is smaller than the MAI, then it is perfectly safe as the body is equipped to handle a certain level of extraneous substances in the food.

However, if we REGULARLY take a small amount of a potentially toxic substance, we may still “get poisoned” over a long period of exposure. This is called chronic toxicity, as opposed to acute toxicity that we discussed in the previous paragraphs. Even for soap, the maximum admissible daily intake (MADI) when viewed from a chronic toxicity point of view becomes an order of magnitude smaller. For instance, for some medicinal soaps, or disinfectant soaps, the MADI may be as low as 50 mg per day for a normal person of 70 Kg body weight.

What about herbicides (also called “weedicides”, but this usage is not scientific)?

Many common herbicides have a very low MADI; that is you can only tolerate very low intakes per day without getting poisoned. But the EXCEPTION is glyphosate. This herbicide is in the same class as detergent soaps as seen from its molecular structure. The MADI for glyphosate is approximately 40 mg for an average person (70 kg body weight).. This was the ruling given by the joint FAO-WHO committee on pesticide residues just recently, in May 2016, when it cleared it of a shadow that had fallen on it after the technical re-classification by WHO where they attributed a possible carcinogenicity to glyphosate. This MADI implies that even if you consume up to eight tea spoons of full strength glyphosate DAILY, no long-term toxic effects would show up. But no farmer actually willingly ingests such arge amounts of glyphosate everyday. It is also impossible to “accidentally” consume such amounts everyday! Even if you DON’T WEAR protective clothing and gloves etc, many many field tests show that the amounts ingested are of the order of micrograms (i.e, a millionth part of a gram or less). Our tea-estate workers rarely wear protective clothing but there are no hospital records to show any chronic consequences of using glyphosate. It has been used extensively in Sri Lanka for nearly two decade, and it is safe enough to be used without special clothes, goggles, gloves etc.

Another writer has stated that “Glyphosate effects are not felt in the upcountry as the hardness of water is low there. But they affect Rajarata areas where hardness of water is high. Glyphosate stays in water for days if not weeks and it washes downstream“. This is sheer nonsense. As we already noted, if there is glyphosate in any body of water, it will not have any green algae growing in it as glypohsate will kill the algae and other water plants (e.g., “japan jabara” or water hyacinth) quite rapidly. No one has detected any glyphosate in the water and soil in the Rajarata. When glyphosate is sprayed to kill the weeds in tea plantations, the glyphosate is rapidly used up by absorption into weeds and into the soil. If it takes days in temperate climates for glyphosaate to bio-degrade, it happens in a much shorter time in the tropics. The soil bacteria break it down very rapidly. Even though up to 2 mg of glyphosate is allowed to be present per kilogram of tea by international controlling agencies, it is not normal to find even micro-gram quantities of glyphoste in Sri Lankan tea. Our tea is safe and virtually free of glyphosate while granting that glyphosate is in any case a safe herbicide. That is why a group of scientists, including seven past director s of agriculture appealed to the president to lift the ill-conceived ban on glyphosate.

Neem, an organic pesticide and fetlizer as well.

Let us compare glyphosate to Neem extract (i.e., extract from Kohomba, Azadirachta indica). Neem contains many aromatic acids, ketones and other active organic substances like nimbandiol, n-hexacosanol nimbiol etc. These have mild pesticide action, but they are no match for the tough weeds and insects found in plantations. However, they are toxic and definitely far more toxic than glyphosate when it comes to non-plant organisms, as can be demonstrated by observing the effect of Neem extract on a sample of micro-organisms. In contrast, glyphosate has virtually no effect on microorganisms, as it acts exclusively on plants (i.e, cells having chlorophyll) at the concentrations that one is likely to encounter in real life.

Growing plants accumulate naturally occurring metal toxins from the soil and concentrate them. Kohomba is an efficient bio-accumulator. Growing Kohomba on soil which has become polluted is a good way of soil remediation. But if such Kohomba plants are used to make compost or Neem extract, such “organic” Neem products (be it fertilizer or pesticide) willl themselves be full of toxins. “Organic vegetables” and crops grown using such “organic” fertilizers are likely to be laced with toxins. Most organic fertilizers are faced with this problem due to bio-accumulation of toxins. Customers of “organic food” may be ingesting food containing more toxins than standard food!

“Organic pesticides” are totally ineffective and impractical for large plantations. To do the job of 1 kg of inorganic fertilizer or pesticide, a ton of organic fertilizer or pesticide is needed. They may have a place if large-scale plantations of vegetables, tea, rubber, paddy etc., are abandoned for small-scale mixed-crop plots form of agriculture can be practiced. But one cannot transit to a new cropping model overnight, or even in several year. It is not even clear if such a transition will ever be possible. Given the limited arable land we have in Sri Lanka with its bulging population, organic-cropping models using homemade “organic” compost, and manual weeding will simply lead to the starvation of large segments of the population. The “organic food movement” is becoming a program that attempts to transform the food industry into one that caters to the rich upper classes, while neglecting the poor who are in large numbers. They, having no voice, are being edged out of affordable food.

Kidney disease.

Recent investigations have confirmed the fact that those who contract kidney disease are those who drank water from their own homestead wells, while those who drank the water in irrigation canals, rivers and tanks remained free of the disease. Thus some people in the same village may get kidney diseases, while other co-villagers remain free of the disease depending on their source of drinking water. If any agrochemicals cause chronic illnesses, and if they came down the rivers from the hills, then it is the people who drink river water who should get sick; but the opposite is true. This again proves that agrochemicals have nothing to do with kidney disease found in the Rajarata. Furthermore, when people write that “Glyphosate stays in water for days if not weeks and it washes downstream” to the Rajarata , they engage in sheer wishful thinking. Glyphosate has become a phantom. No glyphosate has been found in any water bodies in the Rajarata or upper Mahaweli. It is also being irresponsible in generating hysteria and panic among the public by complete fabrications of things and “toxins” that do not exist in our water or soil. It was by such fear-mongering that the ban on glyphosate was achieved. But at last the government has listened to scientists and become wise to the machinations of the myth makers, “kattadiyas” and Kelaniya psychics.

The way to tackle kidney disease is to provide clean drinking water to those who are using their house-hold wells which are contaminated with unhealthy salts and possibly unidentified toxins. These arise from the nature of the soils, salts, algae growth and chemical processes that occur in stagnant wells dug into the dry zone soil. Banning glyphosate will not help kidney patients or Rajarata residents., because, even without a ban, there is already NO glyphosate in the Rajarata soil, water or food chain.