Nanotechnology, the science of building systems at a molecular level, could be hit by the same backlash that has dogged genetically modified crops, according to a medical ethics think-tank.

A study by the Joint Centre for Bioethics at the University of Toronto, Canada, published in the UK journal Nanotechnology, has warned that the science of the very small could be derailed if the ethical, environmental, economic, legal and social implications of it do not catch up with its technical developments.

Innovations in nanotechnology include single-molecule transistors, an enzyme-powered bio-molecular motor with nickel propellers, and a tiny carrier able to travel from the blood to the brain to deliver tumour-fighting chemicals.

The report said that although the emerging knowledge has the power to revolutionise society, its power to exploit the potential of extremely small-scale systems is outrunning our capacity to digest its implications.

It cautioned that without more thought for ethics there could be calls for a ban on nanotechnology developments.