Chinese Experience Shows Adverse Environmental Impacts of Genetically Engineered Bt Cotton
Beijing/London, 3 June, 2002 – A Greenpeace report reviewing Chinese experience of genetically engineered (GE) Bt (Bacillus thuringiensis) cotton shows adverse environmental impacts after just five years of commercial growing, concluding that the variety will be ineffective in controlling pests after eight to ten years of continuous production. (1)
Laboratory tests and field monitoring conducted by four Chinese state- owned science institutes (2) verify a resistance build-up towards Bt in the main target pest, cotton bollworm, a significant reduction of the parasitic natural enemies, and an increase of secondary pests. These factors have forced farmers to continue the use of chemical pesticides, and increased the possibility of outbreaks of certain pests due to the destabilized insect community.
The author of the study, a researcher at the Nanjing Institute of Environmental Sciences, and an advisor for Greenpeace, Professor Xue Dayuan, said: “The report confirms that the Bt cotton is released to the environment prematurely. After five years of growing, Chinese farmers and scientists are now faced with serious problems and confronted with the fact that too little is known about the interaction of GE crops with the environment. High hopes have been brought crashing down and reality shows that the information from the GE industry has been unsubstantiated.”
Bt cotton, a genetically engineered variety inserted with a gene from soil bacteria to produce a toxin that kills certain types of pests, was first introduced to China in 1997 by Monsanto. It was advertised as a magical fix to pest problems. Since then the area of cultivation has increased to 1.5 million hectares in 2001, which is 35% of the total cotton area. Monsanto’s Bt cotton accounts for two third of all GE cotton grown in China.
According to the report titled “A Summary of Research on the Environmental Impacts of Bt-cotton in China”, laboratory tests for selection of Bt-resistant bollworm indicated that susceptibility of bollworm to the Bt toxin fell to 30% after 17 generations under continuous feeding with Bt cotton leaves. The resistance of the bollworm increased 1000 times when the feeding was continued to the 40th generation. Moreover, the population of parasitic natural enemies of cotton bollworm was reduced significantly in Bt cotton fields. Secondary pests, such as cotton aphids, cotton spider mites, thrips and others, replaced the cotton bollworm as primary pests in some of the cotton fields. In addition, the resistance of Bt cotton to cotton bollworm decreases over time.
“As farmers growing this GE crop are now finding themselves entangled in Bt-resistant superbugs, emerging secondary pests, diminishing natural enemies, destabilized insect ecology, and the need to keep spraying chemical pesticides to deal with the increasingly uncontrollable situation, will Monsanto deal with any of these problems their lack of precaution have caused?” asked Lo Sze Ping, Greenpeace China Program Manager.
“The Chinese Government has a role in helping the international community to ensure that corporations such as Monsanto are held liable for the damage they are causing by having developed and released GE crops,” Lo added.
(1) The study available from Greenpeace web site http:///www.greenpeace.org
(2) The report reviewed the research data of four state institutes: Institute of Plant Protection, Chinese Academy of Agricultural Sciences (CAAS), Cotton Research Institute of CAAS, Department of Plant Protection, China Agricultural University, and Department of Plant Protection, Nanjing Agricultural University.