(CBSNEWS) – A lawsuit accuses popular sparkling water brand LaCroix of misleading customers by calling its product “natural.” The suit accuses LaCroix’s parent company, National Beverage Corporation, of “using non-natural flavorings and synthetic compounds.” The company denies the allegations.

The lawsuit comes as a growing number of foods promoted as “natural” face criticism, reports CBS News’ Anna Werner. While there’s no official government guidelines as to what qualifies a product as “natural,” there’s no denying the word is an effective marketing tool. Consumer Reports says 73 percent of customers actually seek out foods labeled as natural. The question is, what are they actually getting?

(CBS News)

Touted as a “natural” sodium and calorie-free alternative to soda, LaCroix’s sales were up 17 percent last year.

The lawsuit says synthetic chemical compounds are added to LaCroix to make the drink “taste or smell a certain way.” The suit claims one ingredient causes kidney tumors and another is used as a cockroach insecticide. But nutritional scientist Roger Clemens says the compounds are considered safe.

“These compounds are found in nature, mostly in fruit such as oranges, limes, strawberries, pineapples, bananas….so we consume these compounds every day if we eat any kind of fruit,” Clemens said.

But it will be up to a jury to determine whether those compounds found in LaCroix are derived from natural substances or are created artificially. Parent company National Beverage Corporation says the ingredients are “derived from the natural essence oils from the named fruit used in each of the flavors” and “are certified by our suppliers to be 100% natural.” Still, the labeling is part of a larger problem because there’s no industry standard as to what the word means.

“I believe that consumers today are confused with the word ‘natural.’ They believe ‘natural’ means safer, natural means more wholesome,” Clemens said.