The company claims it was just a misprint and they are working with the FDA to rectify the issue

Two ingredients, ferric ferrocyanide and ultramarines, listed in one of the brand's Velventine matte lipsticks are not approved for use in lip products

A popular make-up brand whose products are sold at Urban Outfitters stores is now under investigation by the US Food and Drug Administration for listing potentially harmful ingredients in one of its beloved lipsticks.

Lime Crime, a cult beauty brand known for its wide range of colors and uber-girly packaging, received a warning letter from the FDA in July for listing ferric ferrocyanide and ultramarines as ingredients in its Velvetines matte lipstick. Neither of those synthetic pigments is approved for use in lip products in the US.

While Refinery29 reported that Lime Crime is claiming that this was merely a misprint, e-retailer NastyGal has already chosen to stop selling the brand's products.

Uh-oh: Make-up brand Lime Crime has received a warning letter from the FDA for listing two ingredients on a lipstick label that are no approved for use in lip cosmetics

Hue under fire: Synthetic pigments called ferric ferrocyanide and ultramarines are listed on the label for the Velvetines lipstick in Red Velvet (pictured)

Under the Federal Food, Drug, and Cosmetic Act, the use of ferric ferrocyanide and ultramarines is prohibited in lip products in the US. While they can be used in eyeshadows or blush, they are off-limits for lipsticks and glosses because of the risk of ingestion.

The ingredients are, however, approved for lip products in Europe and Asia.

On July 29, the FDA sent a warning letter to Lime Crime, informing them of the violation and advising them to 'promptly correct' the problem. Specifically, the two ingredients in question are found listed on the label for the Velvetines lipstick in the color Red Velvet, which sells for $20.

Lime Crime responded to the warning, and also released a statement on its website that read: 'Lime Crime has been in active communication with the FDA regarding the letter and following their instructions to resolve it as quickly as possible.'

It went on to explain: 'As per FDA, Lime Crime is providing documentation demonstrating that these ingredients are, indeed, not part of the Velvetines formula and it's a simple labeling error. We are confident that once the FDA reviews the proof, they will consider the case resolved.'

Denial: The brand claims that the ingredients, which are approved for use in eyeshadows and blush but not lipstick, are not actually in the product and the label is misprinted

Fixing it: The FDA only found ingredients listed on the label for one color (not pictured), and those ingredients are no longer listed for the color on the brand's website

The company claims that those two potentially harmful ingredients are not actually in the Velvetines lipstick at all, and their inclusion on the label was just a misprint. They are also not listed as ingredients on the company's website.

Unfortunately for Lime Crime, though, that still places them in violation of FDA regulations, as all cosmetics are required to be labeled accurately.

Whether the ingredients are actually present is still unclear, since the FDA hasn't actually tested the products. In fact, the FDA doesn't usually test cosmetics before they hit the market at all- except sunscreen and products with certain color additives.

'Cosmetic products and ingredients, other than color additives, are not subject to pre-market approval by the FDA,' FDA press officer Megan McSeveney told Refinery29. 'But, once on the market, the FDA can take action on cosmetics that do not comply with the laws and regulations we enforce. If we become aware of a specific health concern, we will take additional steps to inform the public.'

Bit of a boycott? NastyGal has stopped selling Lime Crime cosmetics, but they are still available from Urban Outfitters

Time to reprint: Even if the ingredients are not actually in the matte lipstick, the brand is still in violation because its labels are inaccurate

Rather, whether or not there are illegal or unsafe ingredients in cosmetics is largely determined by the honor system. Some big companies like L'Oréal have toxicologists and doctors on hand who test products before they're sold, but smaller brands like Lime Crime might not - and that's totally legal.

The issue is still being sorted out, and the FDA plans to follow up to 'determine the adequacy of any corrective action taken'.

In the meantime, however, Nasty Gal has stopped carrying Lime Crime for the time being, joining Sephora, which ended its relationship with the brand late last year, before this ingredient issue came to light.

Fans who still wish to buy the lipstick - including both the potentially harmful or perhaps just mislabled Red Velvet color and those that the FDA has no issue with - can still purchase it from the brand's website and Urban Outfitters.

Insecure system? The FDA doesn't test cosmetics before they hit the market

Big brands: Some companies, like L'Oréal, employ specialists to test products before they hit shelves

This is not the first time that Lime Crime has come under fire.

According to the Oh Dear Doe Deere Tumblr, the company has been accused on multiple occasions of repackaging make-up from another brand as its own.

The company's CEO, Xenia Vorotova - who also calls herself Doe Deere - has been accused of claiming to raise money for charity without actually donating it, being rude to customers, and selling products labeled as 'vegan' even though they contained beeswax.