Honest says on product packaging that its laundry detergent is free of sodium lauryl sulfate, but that’s a claim the company making the detergent, Earth Friendly, no longer stands by, according to the Wall Street Journal. Earth Friendly deleted the claim last year after rivals filed a complaint with the Illinois attorney general’s office.

Last week, two lab tests commissioned by the Journal found that Honest’s detergent contains “significant” levels of sodium lauryl sulfate, a chemical common across household products that Honest says irritates skin.

In a statement responding to the Journal’s findings, Honest said that the detergent uses sodium coco sulfate, not sodium lauryl sulfate. “Despite providing the Wall Street Journal with substantial evidence to the contrary, they falsely claimed our laundry detergent contains Sodium Lauryl Sulfate (SLS),” a spokesperson told People.

But despite Honest’s self-defense, many scientists say that sodium coco sulfate contains large amounts of sodium lauryl sulfate.

This isn’t the first time Honest has come under fire for misrepresenting its products to consumers. Last month, a suit filed in New York District Court accused Honest of “deceptively” labeling its product as natural and containing “no harsh chemicals” when the products actually contained toxic and synthetic ingredients.

In a statement to Fortune, a spokesperson reiterated that Honest uses sodium coco sulfate in the detergent. “Just because you can isolate the C-12 carbon chain in a test for SCS does not mean we use SLS in our product,” the statement said. “We use SCS because it is a gentler alternative that is less irritating and safer to use. We stand behind our laundry detergent and take very seriously the responsibility we have to our consumers to create safe and effective products.”

This story has been updated to include comment from Honest.