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British Studies 2000-2002
The British government conducted environmental tests during the years of 2000-2002 to ascertain if GM crops were more harmful to the environment than their conventional counter-parts.
The environmental tests were designed to measure the effects of growing GM oilseed rape, GM beet, and GM maize crops on weeds and invertebrates. The trials showed conclusively that two out of the three crops tested - GM oilseed and beet - harmed wild plants, seeds, butterflies and bees more than conventional oilseed and beet crops. (The trials for GM maize were inconclusive because the herbicide used on the conventional maize had been banned in Europe and its use therefore distorted the results). The trials were important because they were the largest of their kind in the world, but were limited in scope because they only examined the results of growing GM crops for one year. (See commentary of the findings of those studies in the following undated report: L.G. Firbank et.al., The implications of spring-sown genetically modified herbicide-tolerant crops for farmland biodiversity: A commentary on the Farm Scale Evaluations of Spring Sown Crops, 37 pp. E-mail: lgf@ceh.ac.uk.)
Research on the Long-term Impact of GM-Crops
North-American farmers´ experience of GM-crops
A report published by the British Soil Association in 2002 outlines the experiences of American and Canadian farmers after six years of growing GM crops. It particularly highlights how the problems of weeds, pests and so-called volunteer crops have become more difficult to deal with than expected.
(a)
‘Superweeds’: The biotech companies which sold North American farmers GM herbicide-tolerant crops (called HT crops), also sold them a herbicide (weed killer) to use on the crop. The HT crops were genetically engineered to be resistant to the herbicide so farmers could spray the crop - killing the weeds but not the crop. The biotech industry claimed that farmers would only have to spray HT crops once a season thus saving time and money and minimising environmental damage. The report shows that these benefits did not materialise. After three years weeds became resistant (or immune) to the herbicide used on HT crops thus creating ‘superweeds’ which could only be controlled with more use of the same herbicide or applications of more powerful herbicides.
(b)
‘Volunteer’ Crops: Crops planted in one year which reappear in fields the following year are called ‘Volunteer’ crops. They are usually killed off with herbicides before the new season crop is planted. However, there is a problem with removing HT volunteer crops. Because the HT crop is resistant to the herbicide (weed killer) used on them it cannot be used to kill them. GM volunteer crops have to be pulled out by hand or killed off with the application of very toxic herbicides. Because GM volunteer crops are a problem, farmers are tempted to ‘Mono Crop’. Mono-Cropping is the practice of growing the same crop on the same land every year – a practice which is ecologically unsustainable because it depletes the health of the soil and the food grown from it.
(c)
‘Superbugs’: GM Bt crops were genetically engineered to produce a toxin which kills certain insects. Farmers were promised they would not need to spray Bt crops with insecticides because the plants would control the insects. However, as noted in the report, insects eventually develop resistance to GM Bt crops resulting in the emergence of ‘superbugs’ which can only be controlled by spraying highly toxic insecticides.
The report shows that contrary to the claims made by the biotech industry - GM crops require more, not less, use of pesticides than conventional crops. Farmers have not, as promised, saved money or time growing GM crops, nor has the environment benefited from less use of pesticides.
(Seeds of Doubt – North American farmers´ experiences of GM crops, Soil
Association (2002), a report compiled by H. Warwick and G. Meziani.)
Study of the Use of Pesticides
Dr. Charles Benbrook, head of the Northwest Science and Environment Policy Centre, at Sandpoint, Idaho, studied the impact of GM crop production on the use of pesticieds in American agriculture. Reporting on the study, Dr. Benbrook conclusively proves that GM crops use more pesticides than conventional crops.
Using eight years of US Department of Agriculture statistics he showed that after three years the use of pesticides on GM crops increased over the use of pesticides on conventional crops by 5% in 2001, by 7.9% in 2002, and by 11.5% in 2003. In total, 73 million pounds more pesticides were sprayed in the US during 2001-2003 as a result of growing GM crops.
(C.M. Benbrook, Impacts of Genetically Engineered Crops on Pesticide Use in the United States: The First Eight Years, BioTech InfoNet Technical Paper no. 6 (2003).)
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