Letter: GM stowaways

Sir: You report (20 February) the eating of genetically modified tomatoes by Zeneca researchers, seeds and all, and the danger that the seeds may germinate and grow on a sewage farm somewhere in Berkshire, thus spreading the modified genes around in an uncontrolled manner.

Surely we must also be concerned about visitors from countries where GM tomatoes are freely available and eaten? If someone has, for example, eaten a GM tomato in New York prior to flying to Heathrow then the digested seeds could end up in any sewage farm in the UK or Europe.

International travel is making a mockery of any attempts to prevent the release of GM organisms within Britain and other countries which currently do not allow commercial growing of them.