This project was designed to explore the health effects of the products and chemicals used in drilling, fracturing (frac'ing, or stimulation), recovery and delivery of natural gas. It provides a glimpse at the pattern(s) of possible health hazards for those living in proximity to gas development. In the process of researching the literature, we discovered that drilling companies have access to hundreds of products, the components of which are in many cases unavailable for public scrutiny. There are hundreds of products in current use, for which we have information only on a small percentage. We make no claim that our list is complete.