(FORTUNE Magazine) – The battle between chemical companies and environmentalists over chlorine has a new player. And he's getting jumpy.

Groups like Greenpeace want to rid the world of chlorine. Trouble is, nature won't comply. "It would be like banning photosynthesis or gravity," says Dartmouth College chemist Gordon Gribble. Hundreds of animals and organisms manufacture chlorine compounds, like cockroaches and seaweed. And frogs.

The PR potential of this naturally occurring chlorine isn't lost on producers like Dow Chemical and Britain's ICI, which are fighting back with a campaign touting the wonders of the chemical. Their poster child: Epipedobates tricolor, an Ecuadorian tree frog nicknamed Chlement. Get it? The frog produces a chlorine compound called epibatidine, a painkiller up to 1,000 times more powerful than morphine but without the addictive side effects. (Unfortunately, epibatidine is as yet unavailable at your pharmacy or elsewhere.)

To the environmental crowd, Chlement has about as much charm as Joe Camel. "Nature isn't making and dumping chlorine chemicals upstream from fish stocks," says Greenpeace's Mark Floegel. But scientists like Gribble point out that the chlorine industry has come a long way. DDT and PCBs, the most notorious members of the chlorine family, have been banned. And paper companies have switched to chlorine dioxide, a less harmful form of the chemical. But Chlement won't be hopping to peace talks soon. "There isn't any common ground," says Floegel. "We're trying to put those companies out of business."

- Ruth Coxeter