A RESEARCH team at Fudan University has invented a lamp that can eradicate unpleasant odors without contaminating the environment, varsity officials announced yesterday.

The ultraviolet lamp, minus electrodes, has passed assessment by the Shanghai Science and Technology Commission and is expected to be used in public toilets, garbage-dumping venues, sewage-treatment factories and other industrial plants, researchers said.

Invented by Fudan's Environment Sciences Research Institute, the lamp is a microwave discharger that can send out UV waves with a wavelength of just 200 nano-meters. The light from the lamp is effective in breaking down unpleasant odors such as those caused by carbon disulfide and hydrogen sulfide.

Hou Huiqi, the institute director, said the lamp can also negate pungent smells sent out by perfume factories.

Earlier environmental reports suggested that, after noise pollution, odors ranked second in public complaints.

The solution proved difficult. "Traditional treatment methods include physical absorption, chemical oxidation and decomposition with low-pressure mercury lamps," said Hou. "Most of these were either ineffective or contaminated the environment."

The new UV lamp has improved the gas-decomposition rate by 50 percent. What's more important is that it uses other gases to replace mercury.