An ominous new word has crept into the life sciences and biomedical research: "biosecurity." The term reflects a growing awareness that rapid developments in these fields offer the potential for great benefits, but that the knowledge, tools and techniques that enable scientific advances also can be misused to cause deliberate harm.

Any effort to address this "dual use" dilemma must ultimately be international, since biotechnology research is a genuinely global enterprise. The international scientific community has a key role to play in ensuring that efforts to manage the risks result in improved security and stronger international collaboration to ensure non-maleficent use of scientific advances.

Professor Ronald Atlas, co-director of the Center for the Deterrence of Biowarfare and Bioterrorism at the University of Louisville, and I recently presented a proposed Code of Ethics for the Life Sciences in the journal Science. Our proposal regarding what we need for a code and for its contents has met with strongly conflicting views. The scientific community increasingly recognizes that science itself is not a value-free activity and, therefore, the choice of what research to undertake and how to undertake it must be governed by ethical principles.

But there is still a nucleus of scientists who oppose that concept, arguing that there must be no restrictions on the search for new knowledge, and that ethical principles only become relevant in the application of that knowledge. In our Science article, we speculated on scientists' reasons for holding such a view. But, as we noted, "even those who question the value of a code agree that research in the life sciences, including bio-defence research, must be conducted in a safe and ethical manner."

A code of ethics is needed because the power of science to result in harm, if it is not well governed, has grown vastly. Society has entrusted scientists and scientific institutions to show respect for life, in particular human life. Safeguards are needed to ensure fulfillment of that trust, more specifically to ensure that science is not used in the cause of bioterrorism or biowarfare.

A code of ethics offers several benefits. It would underscore the importance of ethics reviews of proposed scientific research and monitoring of ongoing research, especially research involving humans or animals as subjects. It can also establish a basic presumption of scientific openness and transparency, while allowing for exceptions when there is a real risk that scientific knowledge could be used to cause serious harm. Moreover, a code of ethics could help protect "whistle blowers" who bring ethical breaches to the attention of the relevant authorities or the public. Finally, it could allow for conscientious objection to participation in certain research. In short, a code can help to embed ethics in all aspects of scientific research from its inception.

Although no consensus has yet emerged on a code of ethics, there is wide agreement among scientists that a robust public health system is an essential safeguard against biological threats, whether intentional or unintentional. Security and public health concerns now overlap, whereas traditionally they had been separate areas that elicited different kinds of policy responses. Strengthening the response to naturally occurring infectious diseases or poisoning is needed to protect against the deliberate misuse of science to spread disease or poison. Promoting public health, biosafety and biosecurity on the one hand, and protecting against bioterrorism on the other, are linked, complementary activities.

But contemplating potential new bio-weapons raises deeply worrying possibilities that return us to the problem of how to ensure ethics in scientific research. For instance, "synthetic biology" involves the creation of living material from its DNA components, so that we can re-engineer life in the manner of our choosing. The technology making this possible will most likely become common within the next two years at a substantially reduced cost. Safe-guards such as a moratorium on such developments or registering the equipment needed to implement them should be considered.

There are ancient taboos on the use of poison or plague as weapons or for warfare, and doing so has long been stigmatized in many cultures and prohibited by customary international law and international treaties. The taboo is the companion to the sacred: that which we regard as sacred we protect with taboos.

We have lost both concepts in relation to much conduct in our contemporary world, but we urgently need to re-find them in relation to the new possibilities opened up by the life sciences if we are to continue to respect all life, especially human life.

The challenge is no less than to prevent the life sciences from becoming the death sciences. That will require complex, multiple, varied and integrated responses from a very wide variety of sources at individual, institutional, societal and global levels.

Above all, it will require integrity, honesty, trust, courage and, sometimes, restraint. This is no small order at the level of international relations and cooperation.

Dr. Margaret Somerville is Acting Director of McGill's Centre for Medicine, Ethics and Law. The article she and Professor Atlas wrote for the journal Science appeared in the March 25, 2005, edition.