Chicago (CBS) — A class action lawsuit was filed in Cook County against the parent company of LaCroix, the popular sparkling water brand. The lawsuit alleges LaCroix falsely claims its drinks are “100 percent natural” and in fact contains synthetic ingredients.

Beaumont Costales, a law firm with offices in Chicago and New Orleans, filed the suit on behalf of Lenora Rice.

“Testing reveals that LaCroix contains a number of artificial ingredients, including linalool, which is used in cockroach insecticide,” a statement from the law firm said.

The lawsuit also claims the drink contains limonene, which can cause kidney toxicity and tumors and linalool propionate, which is used to treat cancer. These ingredients have been identified by the Food and Drug Administration as synthetic.

According to the suit, LaCroix and its parent company, National Beverage, are aware of the synthetic chemicals contained in LaCroix sparkling water but are “intentionally misleading consumers”.

National Beverage Corp. has denied the allegations.

“Natural flavors in LaCroix are derived from the natural essence oils from the named fruit used in each of the flavors,” the company said in a statement. “There are no sugars or artificial ingredients contained in, nor added to, those extracted flavors.”

The three ingredients cited by Beaumont Costales aren’t as dangerous as they might seem, according to Popular Science. Linalool, for example, cited as a cockroach insecticide by the law firm, is found in plants like mints and scented herbs. While it’s also used in insecticides, it’s not poisonous for humans, Popular Science noted.

The lawsuit seeks to stop LaCroix from falsely promoting its products as natural and to award damages to those who purchased the drink under the assumption that it was all natural.

Individuals who have purchased LaCroix and wish to be added to the plaintiff list can contact Beaumont Costales at 773-831-8000.