Dr. Helen McAvoy:

If you smoke only two or three cigarettes a week, unfortunately that does not give you the risk reduction for tobacco-related diseases that we would like. Even at two or three cigarettes per week, you will still have quite bit of risk for tobacco-related disease. It can take up to ten or 15 years to return to the risk level of a non-smoker. Therefore, the dual-use picture is of genuine concern to us. More cynical people than I might say that is part of the business model. There is genuine concern that we will not achieve the harm-reduction effect if so many people are dual-using the products.