National Academy of Sciences

National Academy of Engineering

Institute of Medicine

National Research Council

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences.

The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Wm. A. Wulf is president of the National Academy of Engineering.

The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine.

The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce M. Alberts and Dr. Wm. A. Wulf are chairman and vice chairman, respectively, of the National Research Council.

The work of this committee was overseen by the Ocean Studies Board and the Transportation Research Board of the National Research Council.

This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council’s Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report: Peter Bontadelli (PFB and Associates), Michel Boufadel (Temple University), David Fritz (BP/AMOCO), Stephen Monosmith (Stanford University), Jeffrey Short (National Marine Fisheries Service), Christopher Reddy (Woods Hole Oceanographic Institution), Sylvia Talmage (Oak Ridge National Laboratory).

Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations nor did they see the final draft of the report before its release. The review of this report was overseen by Andrew Solow, Woods Hole Oceanographic Institution. Appointed by the National Research Council, he was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.

Spills of Emulsified Fuels: Risks and Response is part of an evolving body of work conducted by the National Research Council (NRC) to help inform debate and decision-making regarding the ecological consequences of releases associated with the widespread use of fossil fuels. Like earlier NRC reports, it attempts to understand the chemical, physical, and biological behavior of a complex mix of compounds that make up various petroleum hydrocarbon-based fuels. The specific risk factors presented by emulsified fuels are difficult to characterize, mainly because there have been no spills of emulsified fuels to date, and thus there is little practical experience with these products.

The Committee on Spills of Emulsified Fuels: Risks and Response faced some special challenges in the conduct of this study. First, it had to evaluate a new product with very little real-world data for validation of the assumptions used in models and risk assessments. In addition, the committee had to evaluate a new formulation as of 1998, when much of the early research results were for the previous formulation. It became necessary to decide which results could be applied to the new formulation and which results had to be set aside. Second, Orimulsion^® is a complex, multicomponent fuel that, when spilled, behaves very differently than other known types of oil. One of the first activities of the committee was to create its own conceptual models of how this fuel would behave when spilled in different combinations of water salinity, rates of diffusion and dilution, and current speeds. During this process, committee members developed a better understanding of how this product behaves when spilled and the potential for impacts on sensitive resources. These conceptual models became the basis for discussions in each of the chapters on fate and behavior, effects, and response.

Another challenge was how to evaluate the impacts of a spill on top of background levels of widely used chemicals (namely, a specific group of surfactants) that are beginning to be considered as chronic contaminants of concern. Spills by their nature are unpredictable and episodic. How does one evaluate the potential impacts of such events in light of the background of other sources of environmental stressors? There has been a growing recognition of the potential for impacts from surfactants that are widely used in household products as well as industrial applications. The committee had to evaluate potential impacts from spills within the framework of this growing, yet undefined, level of concern for the chronic environmental impacts of this group of surfactants.

Despite these hurdles and the tight time frame, what follows is, in my opinion, a very credible review of the work completed to date and an evenhanded discussion of the remaining questions. As with all such efforts, only the hard work of the committee members and the NRC staff made the report possible. I would like to take this opportunity to recognize their contributions.