Biotech crops bring higher yields with solid environmental benefits: less use of energy, better soil conservation, less fertilizer employed and therefore less polluting runoffsintosgroundwater. But the voices opposed are also loud. Prof. Bruce Chassy, an American expert in the field, was recently in Beijing for an international conference; our journalist took the opportunity to interview him on the subject.

　　Q: The people who denounce biotechnological crops say they are worried about the possibility of the alien genes in genetically modified crops spreading to other species. For example, suppose herbicide-tolerant cotton transmits its genes to weeds - then the weeds could become“superweeds”. Do you think this concern is justified?

　　A: Before a new biotech crop can be grown in the USA, it must be approved by the US Department of Agriculture and the Environmental Protection Agency. They require developers to provide evidence that there will be no unex-pected or damaging environmental consequences if the crop is planted. The questions require an examination of the potential for gene flow and any consequences that would ensue, including issues such as superweeds and the impact on a variety of non-target species such as birds, butterflies, earthworms and frogs. Resistance to the herbicides used in conventional agriculture does occur from time to time, and there is no reason to believe that biotech crops will produce any different kind of herbicide-resistant weeds than we already see in agriculture. In fact, after six years of planting herbicide-resistant crops in the US, we have not seen the emergence of herbicide-resistant weeds.

　　Q: I am told that in the UK Prince Charles has publicly opposed biotech. He says he is worried that God's role in creation will be usurped by engineers and scientists - religious people have always regarded God as the creator of species. Most of the people in the US are Christians too. How come they don't oppose biotechnology?

　　A: Prince Charles, like all of us, is entitled to his opinion. He is, however, not a scientist and although as future king he will one day become the“Protector of the Faith”in the Church of England, he does not speak for all Christians. There is more than one Christian church in the world. The Roman Catholic Church, for example, has endorsed biotechnology as a science that can provide great benefits to mankind. They see no ethical issue working against its use. Also, remember that the US is not officially a Christian country; although many Christian people live there, all of us work hard to keep church and religion separate from policy and politics. We are a diverse and multicultural society with many faiths represented, and many forms of the Christian faith are practiced among us as well.

　　Q: A British scientist I interviewed a while back told me that people in the UK don't believe scientists and think of them as strange persons. How do Americans think of scientists?

　　A: I suppose some people in the States would say the same thing. Scientists are a bit unconventional at times. The general public in America respects science and technology as well as scientists. Many realize that our success as a nation has been in part accomplished through science and engineering excellence.

　　Q: In the US what percentage of people support biotech crops? And do those who support biotech crops also eat biotech crops? What percentage of food on the market has genetically modified ingredients?

　　A: US consumers have been subjected to a very effective anti-biotechnology propaganda campaign for the last few years, but according to polls over 70% support biotechnology. For example, in a recent referendum in Oregon, voters rejected a proposal to require special labels on all products containing biotech ingredients by an overwhelming 73% to 27%. That's probably because consumers know that we have an effective regulatory system. Many may also know that 70-80% of the processed food products on supermarket shelves contain one or more ingredients derived from biotech crops. All Americans eat biotech crops unless they deliberately seek out products that are labeled otherwise. Evidence suggests that this is less than 5% of consumers.