Increased awareness about using a highly technical process called hydraulic fracturing to recover natural gas trapped deep within the Marcellus shale has created questions about related human-health and environmental impacts. Associated arguments, both pro and con, have often been subjective, emotional, and unscientific. This publication by the American Council on Science and Health (ACSH) is a systematic, objective review of documented types and rates of hydrofracturing-fluid- and chemical-related incidents affecting human health, to date, in the region of the Marcellus Shale
