Is Bt brinjal good for you?

The Genetically Engineering Approval Committee (GEAC) (can't we have more feliticiously named committees?) has approved the commercial cultivation of the humble brinjal, alias eggplant alias aubergine. Of course it still requires clearance from the Ministry of Environment and Forests (where decisions will be based as much on politics as science -- perhaps more so). But the knives are out already and the habitual pulpit-thundering anti-technology naysayers like Vandana Shiva and others of her ilk, including scores of NGOs have predicted the usual gloom and doom scenario for Indian agriculture, particularly those cultivating this poor unloved vegetable.

Before we get to grips on this issue, let's get some incontrovertible facts out of the way.

• This is not the first genetically engineered seed to be sanctioned for commercial cultivation. So called Bt cotton was the first (in 2002) which at least superficially has been an unqualified success with 50% better yields and is also grown in US, China, South Africa and Australia. However, since nobody eats cotton, the issues in this regard are different from those of eggplant and have more to do with commercial, social and economic aspects. (For example, the ability of the farmer to harvest the seeds from his own crop for the next planting, rather than buying it again from the market). Consumption of genetically modified foods bring up totally different issues altogether, some of which I will discuss below.
• India is by no means a trendsetter in this regard. The US has 62.5 million ha under cultivation, Argentina has 21 million ha, Brazil has 15 million ha. India is now fourth in this list with 7.6 million ha, mostly growing cotton, followed by Canada and China. The crops grown are also more diverse -- canola, maize, soyabean, sugar beet, tomato and of course cotton.
• It is not just professional objectors like Shiva who are against transgenic crops. Even respected molecular biologist P. M. Bhargava has added his voice to this chorus.

As far as I understand, the main reasons for the worry are the following, some of them only relevant in the Indian context.

• A general belief that fiddling with the genetic structure of any food must have adverse consequences. There is unfortunately no proof of this yet -- it appears more a matter of faith. There have never been any reports of adverse health effects from the consumption of GM foods and by now the numbers of such consumers are significantly large.
• The clearance by the GEAC was done hurriedly and based on data provided by the company which markets this product -- Mahyco (Maharashtra Hybrid Seed Company) -- a subsidiary of the (evil?) multinational Monsanto. There was no independent verification of the field trials and even though Indian Governmental organisations like ICAR (Indian Council of Agricultural Research) and IIVR (Indian Insitute of Vegetable Research) were involved, the tests were superficial, the results rushed out in a hurry, and there was no transparency in the trial methodology. People like P. M. Bhargava have been particularly troubled by these aspects.
• The whole GM food control, and therefore eventually all of Indian agriculture is coming more and more under the control of multinationals like Monsanto. This is an economic issue though, not a scientific one and in this post I want to address mostly the scientific issues.

So what are these scientific issues? (I am by no means an expert on this issue and most of the information in this post comes from an excellent article by The Harvard zoologist and biologist Richard Lewontin in the New York Review of Books. However that requires a subscription to the magazine though I could send you a copy on an individual basis to avoid copyright problems.)

Human beings have been genetically modifying organisms since the domestication of plants and animals. The usual way we have been doing it for tens of thousands of years is to selectively breed those variants of a plant which have desirable qualities like better productivity or resistance to pests. These are also only done between closely related species. Moreover, this kind of "mixing" can be a bit of a hit or miss affair and while improving one aspect (say disease resistance) one might also selectively propagate a low yielding variety of the plant. Modern genetic engineering instead selectively removes the DNA corresponding to a particular gene and inserts it into a recipient's cell so that it becomes part of the recipient's genome. The 'source' DNA can belong to a distant species and in that case the resultant variety produced is called a transgenic organism.

One of the most famous cases of genetic engineering (to which nobody seems to have ever objected) is the introduction of the human insulin gene into the genome of bacteria which, subsequently, after being grown in industrial quantities produce industrial quantities of insulin that keep millions of diabetics in good health.

One of the commonest uses of trangenic DNA is to make plants resistant to pests. The Bt protein is a powerful toxin made by the bacterium Bacillus thuringensis (hence Bt) and when the gene coding for this toxin is inserted into plants, they start producing these toxins and insects trying to feed on these plants ingest these and die. The obvious issue that exercises opponents of GM crops is the effect of these toxins on human beings when they eat GM varieties of fruits and vegetables. This, along with two other issues - the disruption of the natural environment of agriculture and the development of resistant pests are the three main problems with transgenic foods. (Incidentally it is a fact not often recognised that adverse toxic health effects can also arise during conventional breeding including crosses between species that normally do not cross in nature -- in fact there are several such examples in the history of agriculture referred to in Lewontin's article).

Large scale testing by independent agencies is the only way out of these problems. Unfortunately not just in India but even in advanced countries like the US, it is often true that the data on which 'safety assessment' is based are produced not by independent federal agencies but by the the very parties who are asking for approval to distribute the new variety. This is precisely what makes the propagation and large scale production of GM foods somewhat of a risky enterprise. Self-policing is hardly calculated to inspire confidence in the minds of the general public towards the safety of transgenic varieties of food. However it is also true that in the last two decades or so, there has not been a single proven case of adverse effects directly attributable to a transgenic crop. (A close call is mentioned in the Lewontin article). Hardened weed varieties are another undesirable by-product of this genetic manipulation.

If these were the only issues on which the GM crop antagonists were fighting the battle, it would be the action of a responsible opposition. Unfortunately the movement has almost taken on the contours of a belief system based on a hardened and pathological dislike for any technological intervention in natural processes. (It's not surprising that most of the opponents of the system are also opponents of the Green revolution in India that finally abolished large scalestarvation and frequent occurrences of famine in the country and allowed India to become self sufficient in food). The poster-person of this movement is of course the well known activist Vandana Shiva. Shiva, who we are told is a former physicist, blots her copybook by making remarks (in her famous book Stolen Harvest) that have nothing to do with science. For example, that seeds and biodiversity are "gifts from nature and their ancestors" and her opposition to genetic engineering is based on "a recognition in the Isho Upanishad that the universe is the creation of the Supreme Power meant for the benefit of all creation". Further on, in the book, she talks of "the smoke from the mustard oil used to light the deepavali lamp acts as an environmental purifier." (I should confess here that I have not read the book though the above are actual quotes from there. Perhaps she is being quoted out of context! And yet, if even her best arguments have to be buttressed by this kind of pseudo scientific mumbo-jumbo, it is not a surprise that people like her do not inspire much confidence amongst most scientists). As Lewontin reports, her book is full of unexplained claims about the nature of the farm economy in India, and how biotechnology destroys it and unanalysed or distorted scientific findings, some of which are explicitly referenced in the review. As Lewontin puts it, Stolen Harvest is an opportunity squandered.

And yet, many serious scientists have questioned the wisdom of hurrying through with the clearance for Bt brinjal in India, without conducting fully independent large scale field tests. GM crops if used appropriately can be of great benefit to poor farmers in countries like India but in order to be able to sell the idea to the people of the country the Government has to do more -- if not anything else, at least to make sure that field tests are not only done fairly but also seen to be so.