The reason is this:

This study provides further evidence that vaping is a much safer alternative to smoking.

I had intended to blog about your recent paper, but decided instead to write an open letter and to put these concerns to you directly. So, I write to express dismay at the false, misleading and damaging conclusions you have drawn from your recent paper in JAMA Pediatrics and related media communications. The errors of reasoning are elementary, but have been used to draw conclusions that are relentlessly hostile to e-cigarettes and the important public health concept of ‘tobacco harm reduction’.

This issue is particularly important because based on the arguments of these authors, the FDA should ban filtered cigarettes in order to protect the public's health. But in my opinion, such a move could be disastrous because it would result in a dramatic increase in tar delivery and possibly carcinogen dose, potentially leading to an increase, rather than a decrease in cancer.

The complete quote from this article:

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