In collaboration with Rodale Press, this recommendation comes from the Today Show Health website. The title of the article is 5 Toxic Chemicals You Should Banish from Your Home by Leah Zerbe states that the problem with coal tar sealants stems from the quantity of toxic polycyclic aromatic hydrocarbons in the material.
The article goes on to say that Lowes and Home Depot have ceased sales and that alternatives exist either as sealants or a greener alternative, porous pavements. Some smaller hardware stores and many professional sealcoating companies continue to use coal tar in most of the United States and Canada.