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Your Environment. Your Health.

The GuLF STUDY (or Gulf Long Term Follow-Up Study)

Closed for Recruitment

Study / Trial Background

The GuLF STUDY is a study of health of clean-up workers and volunteers who responded to the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.

The National Institutes of Health (NIH) is sponsoring this study. The National Institute of Environmental Health Sciences (NIEHS) is leading this research with the support of many local community groups. The GuLF STUDY is designed to find answers to the questions that matter to oil spill clean-up workers and affected communities.

Between 2011 and 2013, about 33,000 participants joined the study by completing a telephone interview, making it the largest study ever conducted on the health effects of an oil spill. Participants include adults ages 21 and over who helped with the oil spill clean up, took training, signed up to work, or were sent to the Gulf to help in some way. More than 11,000 of the participants from the five Gulf coast states completed home examinations, which included additional questionnaires and collection of biological and environmental samples.

The study will examine how different aspects of oil-spill clean-up may affect current and future health. The study will also examine how stress and job loss because of the oil spill can affect health, including mental health. By comparing workers doing specific clean up jobs to others who did not do those jobs, we can learn if health problems are occurring at a higher rate than expected among some groups of workers. The findings from the study may influence long-term public health responses in Gulf communities or responses to other oil spills in the future.

About 76% of participants helped with the clean-up effort some way, and the other 24% trained to work but did not help with clean-up. Participants who worked or volunteered helped with every aspect of clean-up, and some did multiple jobs. The images below shows all the places participants worked.

For more information on this study, please visit the Clinical Trials Study webpage.


The study has completed enrollment.

People from across the U.S. and from all walks of life came together to clean up the coast after the Deepwater Horizon Oil spill. Study participants, who represent the full range of oil spill clean-up responders, generously gave their time to answer in-depth questions about their experiences during the spill and their health. Many participants also allowed us to visit their homes to collect blood and other samples. The willingness of participants to join the study and share their stories has helped make the GuLF STUDY the largest and most comprehensive study ever conducted on the potential health impacts of an oil spill.

About 83% of study participants live in the five Gulf coast states, but 17% come from across the US.

What will you do?

The follow-up phase of the study is currently underway. During the follow-up phase, you may be asked to all or some of the following: 

  1. Update your contact information 
  2. Complete a 30-minute telephone questionnaire 
  3. Participate in a clinical examination at a medical center

What will NIEHS do?

The GuLF STUDY is currently tracking the health of participants by conducting follow-up telephone interviews that include detailed health questionnaires. Some participants will also be invited to take part in clinical examinations to explore the long-term effects of the spill.

Newsletters describing the progress and findings of the study will be mailed to people in the study every year. These reports will be posted on the study website. Results of the study will be reported in publications that are read by physicians, public health professionals, and scientists. Local, state, and national media groups will also be informed of study findings. We will hold community meetings to report results and send newsletters and reports from the study to interested groups.

Study / Trial Location

University of South Alabama
Louisiana State University

Protocol Number: 11-E-N076

Enrollment and Contact Information

For more information please visit the Gulf Study website.

Questions About the Gulf Study from members of the press should be directed to Christine Bruske Flowers, Director, Office of Communications and Public Liaison at the National Institute of Environmental Health Sciences. She can be reached at (919) 541-3665 or by e-mail.

Principal Investigator

Photo of Sandler, Dale P.
Dale Sandler, Ph.D.
Chief, Epidemiology Branch and Senior Investigator
Tel 984-287-3711
Fax 301-480-3290
P.O. Box 12233
Mail Drop A3-05
Durham, N.C. 27709
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