While risks for fatalities and the nature of occupational safety hazards are well documented for upstream workers, the scope and magnitude of chemical exposure health risks are not well described (or, at least are not published in the peer-reviewed literature). Exposure to respirable crystalline silica is an occupational health hazard for crews at hydraulic fracturing sites. Sand mover and T-belt operators appear to be at greatest risks for exposures, but other on-site crew members have risks for exposures as well. Additional exposure risks in oil and gas extraction include H2S, hydrocarbons (for example, benzene), diesel particulate matter, lead, acids, a variety of biocides, and naturally-occurring radioactive materials (NORM), which includes a variety of terrestrial isotopes such as U, Th, Ra and radon daughters. From a safety perspective, highway crashes and struck-by injuries, followed by explosions, workers caught or compressed in machinery, and falls from heights, are the most frequent fatal events in the oil and gas extraction industry. One overarching and consistent finding is that small companies (those with fewer than 20 employees) and workers with less than one year of experience with their current employer have the highest fatality rates and should be a focus for improved safety efforts. Industrial hygienists and safety professionals can make needed and valuable contributions to the profession in the area of oil and gas extraction safety and health. However, these contributions need to balance a focus on the soon and certain hazards that, if uncontrolled, can cause acute injury or even death, with the need to anticipate, think, and understand the risks for the long and latent: chemicals (or minerals) that may cause disease years or decades after exposure. NIOSH will continue to focus on research needs, build collaborative relationships with industry partners to further research to prevent fatalities, injuries and exposures, and work to improve the overall health and safety for workers in this industry.