A Portland-area company that sells cannabis extracts for vaping has removed one of its signature products from its website as scrutiny intensifies about the health risks of cannabis vape oils.

Andrew Jones, who owns Connoisseur Concentrates in Tigard, Oregon—a lab that extracts butane hash oil from marijuana—writes in a public letter that he has discontinued the sale of a line of dilutant products that he started selling this spring that contain vitamin E acetate. The line of products is called "Clear Cut."

The letter is addressed to a cannabis resource website called Leafly, which published an article on Sept. 6 detailing how several companies known for producing dilutants for vape pens that contain Vitamin E acetate had "gone dark." The article noted that Connoisseur Concentrates had pulled its "Clear Cut" products off of the online website.

In the letter, Jones confirms Clear Cut contained Vitamin E acetate. He says that his company released the product line in May and it was approved by the Oregon Liquor Control Commission. He also writes it went through all the appropriate regulatory hoops to be approved.

"We performed our due diligence to the best of our abilities by meeting with the OLCC, disclosing our ingredients, multiple third party laboratory testing, researching FDA guidelines, researching published inhalation studies and more," the letter reads. "At this time the FDA has stated […] 'No one substance, Including Vitamin E Acetate, has been identified in all of the samples tested.'"

Jones' letter comes as some national health authorities are speculating that vitamin E acetate might be the culprit in the recent wave of mysterious lung illnesses in vape users that are being investigated by the U.S. Centers for Disease Control and Prevention.

More than 450 cases of the lung illness have been reported and five people have died from the illness—including one person in Oregon.

Jones is a leading figure in one of the most lucrative segments of the cannabis industry: butane hash oil, the honeylike distilled essence of cannabis plants. That extract can be used in vaporizer pens. He claimed in 2017 that he was making millions of dollars from the machine, called "Mr. Extractor," used to extract the hash oil.

He did not respond to questions over the weekend from WW.

Jones writes that a Los Angeles-based company called HoneyCut first revolutionized diluent thickeners. He writes that these products have become hugely popular. "Through our research and testing we have found that almost every terpene and flavor manufacturer in the country is selling their version of Tocopheryl Acetate," Jones writes.

Jones writes that when he met with the OLCC in the spring, he expressed to them that these additives would be "everywhere" within the next six months.

"The response from the OLCC was that this was news to them, and that they had never heard of it," Jones writes. "We replied the reason for this was that Oregon did not require testing for this product and as of now we believed that this product had already entered the system."

A OLCC spokesman told WW that the agency is working on a response to Jones' letter.

Jones also writes that many of these diluent thickening products are now available through wholesale retailers online.

But he maintains that the Vitamin E acetate is safe—and claims that studies have shown it may have anti-inflammatory benefits to the lungs if inhaled.

"Many studies show Vitamin E to be beneficial to the lungs when inhaled, with studies on beneficial uses for Asthma and the beneficial treatment of burns to lungs from fire and smoke inhalation. If fact, Vitamin E has been studied to help repair the lung damage caused by smoking cigarettes."

Jones writes that his company has discontinued the sale of all Clear Cut products: "As a precaution, we are stopping the sale of all dilutants until we learn more. We have removed our videos, and halted sales out of a preponderance of caution."

He writes that the problem is industry-wide.

"Regardless of what the contaminant is, this in an industry wide problem, each held by manufacturers, resellers, distributors and on down the chain," Jones writes. "Each company deconstructed this product, analyzed it, researched it, cross referenced it to the FDA… and did and everything we knew how to do to provide a good product in the climate we operate under."

It is unclear when the letter written by Jones was published, but it appears to have been published on either Sep. 8 or Sep. 9.