BOSTON, May 14 (UPI) -- A consumer survey indicates U.S. shoppers are expected to double their spending on so-called green or environmentally friendly products next year.

The Landor Associates survey estimates green spending next year at $500 billion, The Boston Globe reported Wednesday. The newspaper said some marketers are taking advantage of the trend and labeling products as environmentally friendly, even when they are not. The term for the deceptive practice is called "greenwashing."

The Federal Trade Commission said the agency is moving up a review of its "green guides," which outline general principles and definitions of environmental claims. The newspaper said terms such as "sustainable" and "carbon offset" weren't widely used when the guides were last updated a decade ago.

TerraChoice Environmental Marketing said a study last year found that 99 percent of 1,018 green advertising claims of common consumer products could be misleading.