Health effects from Exposure to Benzene and Benzene Related Compounds in Residential Communities Experiencing Natural Gas Extraction and Processing Operations

Advancement of natural gas extraction into urban areas across the United States has raised concern for a potential increase in exposure to volatile organic compounds, including air toxics, to the public. Benzene is a primary chemical of concern (COC) due to its classification as a known human carcinogen. Ambient air sampling performed in an earlier study found elevated levels of benzene and 17 benzene related compounds in residential areas where natural gas extraction and processing operations were occurring. Benzene is present in geologic rich formations and released during pyrolysis and venting of fuels. Drilling within city limits has increased the potential for human exposure. The evolution of this study began, as the health effects of exposure to natural gas well emissions are increasingly visible in our society. Study Objective: The main purpose of this study was to determine the health effects that results from exposure to benzene and benzene related compounds in residents of and workers in natural gas extraction sites; To also determine the routes of exposure and the distance that benzene can travel from the point source of generation, and to make recommendations of ways to reduce benzene exposure. Methods: A meta-analysis was conducted and identified all published articles related to benzene and benzene related compounds, and health effects of benzene in residents of natural gas extraction plants and occupational workers. Databases comprehensively searched included: MEDLINE, TOXLINE, PubMed, Scopus, Web of Knowledge, and the Clinical Trials Registry. Reference lists of reports and reviews were also searched. The authors of this paper determined the suitability of the articles by evaluating all related title/abstracts. Articles found relevant were retrieved as full texts and thoroughly reviewed. Health effects of benzene exposure were analyzed based on organ system. Results: Results revealed that exposure to benzene can lead to multiple health effects affecting multiple systems. Health effects can be short term and long term. The health effects were prevalent amongst residents of natural gas extraction sites and people with occupational exposure to benzene. Routes of exposure to benzene are; inhalation, ingestion and dermal. It is metabolized extensively in the liver and can be stored for long periods in adipose tissue and bone marrow. It is excreted in the urine via the kidneys as phenols. Residents in communities experiencing natural gas extraction have higher cases of anemia, leukemia (Acute Myeloid Leukemia, Acute Lymphoid Leukemia), and non- Hodgkin’s lymphoma, which is explained by the hematotoxic effect of benzene. Several studies report that benzene affects the reproductive system, Central nervous system and respiratory system. Recommendations and Conclusion: Use of environmentally friendly hydraulic fracturing chemicals should be encouraged. Residential areas and especially schools should be protected from industrial mining operations. Children exposed to emissions from natural gas extraction/processing should be tested regularly through bio monitoring of urine and blood. Future studies should be done on the effects of benzene exposure to children. Through this study we were able to establish that there is an association between benzene exposure and natural gas drilling in residential communities and the health effects can be debilitating to children, women and workers.