Tighter regulation and control is needed to ensure the safety of nanotechnology - the manufacture of atomic particles - the U.N. said Monday.
In its annual report of the global environment, the U.N.'s Environment Program said "swift action" was needed by policy-makers to properly evaluate the new science.
Although nanotechnology could transform electronics, energy industries and medicine, more research is needed to identify environmental, health and socio-economic hazards, said Achim Steiner, who heads UNEP, in the 87-page report.
The report was released on the opening day of the Global Ministerial Environment Forum, which brought nearly 100 environmental ministers and deputy ministers to Nairobi for the annual conference.
Nanotechnology is technology on the scale of a billionth of a meter, or about one 80,000th of the width of a human hair: the scale of atoms and molecules. The prefix comes from "nanos," the Greek word for dwarf.
Nanotechnology materials are being developed for use in drugs, foods, cosmetics and medical devices. Nanomaterials are already used to make stronger tennis rackets, clothes that are stain-resistant and self-cleaning windows.
Priority must be given to assessing the potential risks of nanomaterials already being mass-produced, UNEP said in its report, entitled The 2007 Global Environment Outlook Year Book and compiled by 80 experts worldwide.
Critics say the science opens a Pandora's box, with warnings that free-roaming nanoparticles or nanotubes - ultra-small pieces of material - could be inhaled, absorbed through the skin or build up in the environment.
People already breathe in millions of nanoparticles a day, but the point is whether the chemicals the particles are made of are harmful.
Although still in its infancy, the nanotechnology industry is booming.
By 2014, nanotechnology is projected to capture 14 percent of the US$2.6 trillion (EUR 2 trillion) global manufacturing market, UNEP says. In 2004 it made up less than 0.1 percent.
UNEP says in its report that it remains unclear what nanoparticles will do when released into the earth's atmosphere, water or soil, the AP reports.
The agency is calling for global test protocols and greater cooperation between private- and public-sector industries and between the developing and industrialized world. UNEP also wants public education about nanotechnology to raise awareness and provide information on the potential benefits and risks.