BATAVIA, Ohio (AdAge.com) -- Colgate-Palmolive Co. in recent months has begun removing triclosan from dish detergent amid growing consumer, regulatory and legislative scrutiny of the antibacterial ingredient. But it's still the key active ingredient in Colgate Total Toothpaste, a billion-dollar-plus global brand.

Even as Colgate last year was rolling out a reformulated version of Palmolive antibacterial dish detergent with lactic acid in place of triclosan, it was significantly stepping up advertising from Y&R, New York, touting the germ-fighting power of Total with triclosan. It's part of an effort to fight off inroads by Procter & Gamble Co.'s Crest ProHealth, which makes similar gingivitis-fighting claims based on use of a form of fluoride instead.

The Food and Drug Administration approved use of triclosan as safe and effective for prevention of gingivitis in Colgate Total in 1997, and that hasn't changed. The pesticide and fungicide has been approved since 1972 for use in low doses as an antibacterial ingredient in a wide range of other products.

But recent studies have linked triclosan to disruption of endocrine systems of rats -- including thyroid function and production of sperm, testosterone and estrogen. The chemical can be found in the urine of 75% of Americans, according to the Centers for Disease Control.

In response to such data, the FDA last year launched a review of triclosan's safety as an ingredient in consumer products, results of which it expects to report this spring, possibly along with proposed regulations. The FDA noted last spring that while triclosan has been found clinically effective in preventing gingivitis, it hasn't been found to work any better than regular soap and water for handwashing.

The moves by Colgate and rival Reckitt Benckiser to remove triclosan from some consumer products came to light late last month when Rep. Ed Markey, D-Mass., who has led a charge for regulatory re-examination of triclosan, released letters he'd received from several consumer marketers.

RB and Unilever said they sell some professional handwash products with triclosan, but either had or were discontinuing use in consumer products. Procter & Gamble Co. and Henkel (maker of Dial) continue to use the ingredient in some dish and hand soaps, respectively.

All pointed to determinations by the FDA and authorities in the European Union finding triclosan safe to use in consumer products, and Henkel noted 2008 research showing triclosan does kill germs better than washing with soap alone.

Even so, there's a notable shift away from triclosan in product formulations.

An RB spokeswoman said in a statement the company will launch a triclosan-free Clearasil face wash this year. "Reckitt Benckiser restricts the use of triclosan to licensed medicinal, over-the-counter drug, cosmetic and toiletry products where it is necessary for specific therapeutic activity," she said.

A Colgate spokesman in an email explained the shift away from triclosan for Palmolive Ultra Antibacterial dish soap as "an improved formula" that's the only dish liquid approved to kill 99.9% of bacteria on dishes in seconds.

In a May letter to Mr. Markey, Colgate Senior VP-General Counsel Andrew Hendry said the formulation changes "reflect the ongoing preferences of Colgate-Palmolive's consumers and other constituents" but reaffirmed the safety and efficacy of Total and anti-bacterial versions of Softsoap, which also continue to contain triclosan.

Colgate is supporting Total with stepped-up advertising, he said, via a global relaunch that started in November in the U.S. focusing on its ability to provide 12-hour protection against gingivitis-causing plaque. Gingivitis can lead to periodontal disease, which in turn has been linked to heart disease, stroke and diabetes, he said, adding that more than 75 peer-reviewed clinical studies affirm the safety and effectiveness of Total -- more than any other toothpaste.

Total is the crown jewel of Colgate brands, likely accounting for more than $250 million in sales in the U.S. alone, said a consultant in the oral-care industry. He sees more regulatory scrutiny of triclosan as "a potential disaster" for Colgate, but said it's unlikely the FDA will take a tougher stance on it than the EU did after a 2009 review.