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The Cost of Silence

The Cost of Silence

Mark Manning, director
Conception Media
84 minutes

The 2010 Deepwater Horizon explosion unleashed a catastrophic amount of oil, gas, and other toxic compounds into the Gulf of Mexico. As the massive spill overwhelmed responders, federal agencies approved the use of chemical dispersants by aerial spraying and injection into the oil plume at its source. Dispersants break up oil, which is highly toxic, into tiny droplets that are, ideally, diluted and decomposed far from beaches and marshes, and far from surface-dwelling mammals, birds, and people. Reducing the exposure of offshore responders and cleanup crews to volatile organic compounds and toxic oil was also a key consideration in 2010. However, the decision to use dispersants was controversial, because these compounds are also toxic and had never been subject to careful epidemiological study. About 3 million liters of dispersant were released—their largest application in U.S. history.

The Cost of Silence, a new documentary by director Mark Manning, offers a more nefarious reading of this decision: that it was part of a conspiracy between the U.S. government and the oil company BP to reduce the firm’s liability and convince tourists and residents that the Gulf was open for business, when, in fact, a dangerous chemical stew was brewing offshore. In the film, Riki Ott, a toxicologist and environmental activist, argues that the dispersant made the oil more toxic and increased the ease with which it was taken up by people and animals. She also maintains that the tiny droplets formed clouds that wafted oil-dispersant mixtures onshore.

Whistleblowers claim that the dispersant was released too close to shore and that cleanup workers used inadequate protective gear. Over 9 years of filming, Manning interviewed offshore responders, cleanup crew members, and Gulf Coast residents who are sick and scared. Some are despondent and others defiant, but all feel abandoned and betrayed by the government.

The film has a polemical tone. Yet whether or not a viewer is convinced that the spill’s impacts were worsened by dispersants, responders and cleanup crews were at the greatest risk of exposure to toxic oil and dispersant. The health of these individuals needs more study, and we need new methods for assessing exposure to spills and dispersants, as recommended by a recent report (1).

Physician Michael Harbut, a consultant on the BP medical settlement, argues that the potential health impacts of the Deepwater Horizon spill on coastal communities will become obvious through epidemiological studies during the next two decades. Manning’s film seeks to accelerate that process and change global policy on the use of dispersants.

References and Notes
1. National Academies of Sciences, Engineering, and Medicine, The Use of Dispersants in Marine Oil Spill Response (The National Academies Press, 2019).

About the author

Department of Earth and Planetary Sciences, University of California, Santa Cruz, Santa Cruz, CA 95064, USA