The findings come as an increasing number of studies - of both lab animals and humans - are revealing that some synthetic chemicals in household products can cause health problems by interfering with normal hormone action.

Called endocrine disruptors, or endocrine disrupting substances (EDS), such chemicals have been linked in animal studies to a variety of problems, including cancer, reproductive failure and developmental anomalies.

This is the first endocrine study to investigate the hormone effects of the antibacterial compound triclocarban (also known as TCC or 3,4,4'-trichlorocarbanilide), which is widely used in household and personal care products including bar soaps, body washes, cleansing lotions, wipes and detergents. Triclocarban-containing products have been marketed broadly in the United States and Europe for more than 45 years; an estimated 1 million pounds of triclocarban are imported annually for the U.S. market.

The researchers found two key effects: In human cells in the laboratory, triclocarban increased gene expression that is normally regulated by testosterone. And when male rats were fed triclocarban, testosterone-dependent organs such as the prostate gland grew abnormally large.

Also, the authors said their discovery that triclocarban increased hormone effects was new. All previous studies of endocrine disruptors had found that they generally act by blocking or decreasing hormone effects.

This finding may eventually lead to an explanation for some rises in some previously described reproductive problems that have been difficult to understand, said one author, Bill Lasley, a UC Davis expert on reproductive toxicology and professor emeritus of veterinary medicine. More analyses of antibacterials and endocrine effects are planned, he said.

Consumers should not take this study as guidance on whether to use triclocarban-containing products, Lasley said. Our mothers taught us to wash our hands well before the advent of antimicrobial soaps, and that practice alone prevents the spread of disease.

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With the discovery of the CF gene in 1989, many scientists began searching for ways to repair the DNA or repair the faulty protein encoded by the DNA.

The new Journal of Biological Chemistry study shows that future research should look at other molecules not directly linked to CF but are involved in the disease process and its side effects, Berdiev said.

Also, the new pictures add to an ever-changing biophysical map of CF used to design future research.

The new pictures were done through collaboration between UAB's departments of Cell Biology, Physiology & Biophysics, High Resolution Imaging Facility and the Gregory Fleming James Cystic Fibrosis Research Center at UAB. Other collaborators are from Ohio State University, the University of Toronto, Ontario, the National Heart Lung and Blood Institute in Bethesda, Maryland and Lambert Instruments in the Netherlands.

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