The growing of genetically engineered (GE) crops is something that Greenpeace has long opposed, due to the risks posed to both human health and the environment, and unwanted contamination of our food due to the difficulties of controlling the spread of these crops. In recent months, news has emerged about how chemical and pharmaceutical giant Bayer has been forced to make massive payouts after conventional US rice crops were contaminated by Bayer’s experimental GE rice in 2006. As a result, Bayer has agreed to a US $750 million settlement for US 11,000 farmers (1). Then, in March of this year, a court ordered Bayer to pay US $137 million in damages to Riceland, a rice export company, for loss of sales to the EU (2).

Back in 2006, Bayer’s experimental herbicide-tolerant and GE “Liberty Link” rice (tolerant to herbicides such as Basta, or Liberty) was found to have contaminated conventional US long-grain rice - including rice for export. Shipments of supposedly non-GE rice, tested and found to be positive for GE rice, were turned back from regions such including the EU, costing companies millions of dollars and prompting lawsuits in the US.

Gambling with human health
But why does this contamination matter, and why should we be worried about traces of experimental GE crops in our food? This does matter and we should worry, because GE experimental crops have, by definition, undergone little or no safety testing to determine their possible impacts on either the environment or human health. Experimental GE crops can contaminate conventional crops during field trials or even illegal plantings. It is often unclear how contamination occurs, and in many cases it could be caused equally by cross-pollination (e.g. via insects) or by human error. Bayer claims that both kind of contamination were an "Act of God".

There are now a number of documented contamination cases caused by experimental GE crops. For example, experimental GE virus-resistant papaya in 2004, experimental GE maize in 2005 (avariety known as Bt10) and experimental GE rice from both US and China (4). Worryingly, these cases are only the ones we know about. We do not know what is being field-trialled as much of the information is kept confidential - including crucial information on how to test for GE contamination in neighbouring crops. This makes it very hard for anyone to check for contamination. The papaya and the Chinese GE rice, for example, were both discovered by Greenpeace – but who else is keeping watch? There are no formal requirements for checking for contamination.

Drugs with your cornflakes?
As you read this, biotech companies are in the process of genetically engineering plants so they literally can “grow” drugs and vaccines in the plants (GE pharmaceutical or pharm crops). Similarly, crops can be genetically engineered to produce various substances (industrial compounds), e.g. for biofuels. Though such GE crops aren’t intended for human consumption, they could contaminate crops just like Bayer’s experimental GE rice did. If the GE gene is passed to a food meant for the table, then humans would unknowingly be eating either drugs or industrial compounds.

The only way to protect our food and environment is to stop releasing GE crops into the environment – and this has to include field trials.

Dr. Janet Cotter is a senior scientist at the Greenpeace International Science Unit, at Exeter University, UK

Image of organic black rice © Greenpeace / Athit Perawongmetha


(2)  Fox, J.L. 2011. Bayer’s GM rice defeat. Nature Biotechnology (News) 29: 473.


(4)  See Genewatch and Greenpeace together catalogue incidences of GE contamination as they occur.