Criteria or guidelines? Dear Sir: In the recent feature article “Environmental Quality Criteria: What Type Should We Be Developing?’’ ( E S b T , Aug. 1991, p. 1352), Peter Chapman argues that the concept of rigid, enforceable environmental quality criteria is flawed, costly, and may not achieve the level of environmental protection for which they were originally designed. He then goes on to develop an alternative framework to eliminate these shortcomings. In this letter we point out a number of inaccuracies made with regards to Canadian activities in the field of environmental quality guidelines and criteria. In addition, we argue that such guidelines and criteria do have an important role in the Canadian framework for protection of the environment. We will conclude by noting that the alternative framework advocated by Chapman is vague and impractical in the real world. In Canada, the Canadian Council of Ministers of the Environment (CCME) is responsible for the development of environmental quality guidelines (not criteria as stated in the article). In North America, there is an abundance of terminology and definitions associated with guidelines and criteria. These terms are not interchangeable as suggested by Chapman but in fact have distinctly different definitions, derivation approaches, and guiding principles. For example, the CCME defines water quality guidelines as “numerical concentrations or narrative statements recomrnended to support and protect a designated water use” and water quality criteria as the scientific data evaluated to derive the guidelines. CCME guidelines are developed in a flexible framework that emphasizes professional judgment. Results of microcosms or field studies have been used to validate laboratory-to-field extrapolations or to derive the guideline value. Guidelines are designed to be a scientific best estimate of a safe limit that affords protection to water uses ( e g , aquatic life, irrigation water, etc.) during continuous exposure. In the United States water quality criteria are designed to protect most uses (e.g., 95% of aquatic biota) and have an acceptable frequency of exceedance.
Chapman’s inference that numerical criteria or guidelines are used as enforceable standards is inaccurate in the Canadian context. In Canada, it is recognized that guidelines are not a statement about the limit at which adverse effects will occur, but rather the limit at which effects could occur. As Chapman quite correctly points out, enforceable standards must take into consideration site-specific factors such as local environmental conditions, availability of technology, and socioeconomic costs. In Canada, these factors are taken into consideration in the development of site-specific objectives and standards. Canadian guidelines are not used as enforceable standards. Rather, the purpose of Canadian environmental quality guidelines is to streamline initial substance assessments and provide a consistent scientific foundation for the derivation of site-specific objectives and standards. In his article, Chapman makes several generic and specific recommendations for safeguarding environmental quality. They include: (1) measurement and assessment endpoints should be the same in order to avoid extrapolation errors from the former to the latter, (2) community and ecosystem-level measures of health should be derived, (3) stop wasting resources on low-priority issues such as oil spills and trendy chemicals and instead focus on high-priority issues such as climate change and stratospheric ozone depletion, and (4) develop a framework, not a number, to determine environmental quality. In evaluating these recommendations, we should keep in mind the major points made by Chapman in criticizing the environmental quality criteria approach: the recommendations must be biologically relevant, replicable, cost-effective, and ultimately safeguard the environment, Chapman’s first and second recommendations are essentially the same-if protection of ecosystem health is desired (the assessment endpoint) then community and ecosystem-level measures [the measurement endpoints) should be developed and used. In theory, implementation of this recommendation would ensure an accurate determination of ecosystem health simply because it is the most biologically relevant approach possible.
001 3-936X19210926-7$02.50/0 0 1991 American Chemical Society
In practice, however, t,he approach by itself fails on Several counts: (1) the results from most studies that have included measures of community and ecosystem health are highly variable and far exceed the variation between laboratory toxicity tests that Chapman found so objectionable, (2) once effects have been detected, the degradation may already be severe, and (3) site-specific studies of toxic chemical impacts on ecosystems become extremely costly when considered on a national or international scale. Nevertheless, if such information is available then it is used to validate and, if necessary, adjust Canadian environmental quality guidelines. With regards to the third recommendation, there is some truth to his contention of misplaced priorities, although it is interesting to note that stratospheric ozone depletion is due almost entirely to “trendy” chemicals such as chlorofluorocarbons and chlorinated solvents, and Kuwaiti oil spills may be contributing to global climate change (Le., a lot of little problems are usually required to create a big problem). Finally, Chapman’s recommendation to develop a framework, instead of a number, to determine environmental health is admirable except that he fails to develop such a framework and, as outlined above, “numbers” should and do play a major role in the framework used in Canada. In summary, we find it distressing that a leading Canadian environmental scientist is apparently so unfamiliar with the Canadian experience that he fails to accurately present key features of Canadian environmental quality guidelines in an E S b T feature article. D.R.J. Moore Commercial Chemicals Branch Environment Canada
R. A. Kent, M. P. Wong, A. R. Davis Water Quality Branch Environment Canada Ottawa, Canada K I A OH3 This letter is the opinion of the authors and not necessarily that of Environment Canada.
Peter M . Chapman replies: I am pleased that Moore et al. have followed my suggestion and have published their comments on my recent feature article in ESbT. GenEnviron. Sci. Technol., Vol. 26, No. 1, 1992 7
erally, we agree, but there are two main areas of contention raised by Moore et al.: first, how closely the Canadian regulatory situation presently ap?r?aches my ideal; and, second, how applicable my ideas might (or might not) be in the “real” world. I t is arguable but immaterial whether or not I am the best person to “accurately present key features of Canadian environmental quality guidelines in an E S b T feature article.” My article was broadly rather than narrowly focused and, aside from a passing comment in the fourth paragraph, did not refer specifically to Canada. However, I apologize for any real or perceived errors in my article. Also, I agree that there are fundamental differences between how Canada and the United States structure their regulations, and I urge Moore et al. to consider detailing such in a future feature article. This is the best way to answer their first concern, and to inform the regulatory and scientific community in general. After all, if a “leading Canadian environmental scientist” (I appreciate the flattery) is truly unfamiliar with the Canadian experience, is it not likely that this unfamiliarity is widespread? Also, Moore et al. are wrong when they state that CCME environmental quality guidelines are not used as enforceable standards; despite best intentions, such occurs all too frequently, particularly when federal guidelines are applied provincially. The resulting confusion and inconsistencies do not help us attain a clean environment. Clearly Moore et al. and I are in agreement in decrying such misuse. The second area of contention, applicability of my ideas to the real world, is, of course, debatable. However, the fact that Moore et al. have misread some aspects of my article may explain the basis for many of their concerns. My first and third specific recommendations (from page 1358 of my article; original wording here whereas Moore et al. paraphrased] are not “essentially the same.” Specific recommendation # I : “Measurement endpoints and assessment endpoints should be the same.” Specific recommendation #3: “Determine community and ecosystem level-specific measures of health; Le., endpoints for communities and ecosystems we want to protect.” My first specific recommendation 8 Environ. Sci. Technol., Vol. 26, No. 1, 1992
refers to directly testing what we want to protect. For example, if our ultimate intent is to protect fish, we should determine effects on fish, not on daphnids. On page 1354 I state: “If, for example, we are concerned with salmon populations in rivers, we should be conducting tests and assessments with salmon, not with surrogates.” I do not know how to make a clearer statement than this. My third specific recommendation goes beyond protecting single species to protecting the health of entire ecosystems. I do not understand how Moore et al. can confuse these two clearly distinct recommendations (individual species and ecosystems). Further, Moore et al. do not propose useful reasons as to why what they, also, conclude is “the most biologically relevant approach possible” should fail. First, they incorrectly accuse me of finding variation between laboratory tests to be objectionable. I do not; what I find objectionable is clearly stated as failure to recognize and factor in uncertainty, particularly for toxicity tests, when such is not the case with, for instance, risk assessments ( 1 ) . Second, their argument that “once effects have been detected, the degradation may already be severe’’ is part of my argument against relying solely on top-down (holistic) approaches (cf. my Figure 4 ) , and ignores my statement on page 1356 that: “both measures [holistic and reductionist] are needed to assess and maintain ecosystem health adequately.” Third, their argument that site-specific studies are “extremely costly” is fatuous. It is much more costly to make the wrong decision(s). Further, the cost effectiveness of site-specific studies (admittedly often expensive initially, but generally much cheaper in the long run) could be improved in many ways. For example, in some cases the ecoregion approach ( 2 ) of EPA’s Environmental Monitoring and Assessment Program (EMAP) could be applied. Finally, it is frustrating to be told that the CCME Guidelines “provide a consistent scientific foundation for the derivation of site-specific objectives and standards,” then be discouraged from such site-specificity for cost reasons! I see no constructive purpose to Moore et al.’s trivialization of the concept of “trendy” chemicals. In my article I clearly indicate that I am concerned with chemicals that
cause real threats and that stratospheric ozone depletion is our major concern. I do not understand Moore et al.’s claim that Kuwaiti oil spills may be contributing to global climate change; I would be grateful for a copy of any refereed journal publication(s) showing such to be the case. I am personally more concerned with the effects of Kuwaiti oil field fires, even though a recent article in E S b T ( 3 ) indicates that: “Significant environmental effects on a global or even hemispheric scale . . . are not likely to occur.” Moore et al. are correct that I have not yet developed a framework; I did not claim to have done so. The main purpose of my article was to point out how some of our present approaches to environmental protection are not achieving their goal and to recommend the development of a new framework to achieve this goal. Development of an effective, workable framework requires, in my opinion: an international, multidisciplinary effort; clear, constructive thought and input; and a “buyin” from a wide range of scientists, managers, regulators, and stakeholders. In this regard, the UN Group of Experts on the Scientific Aspects of Marine Pollution (GESAMP) have recently recognized that “new tasks and challenges as well as new developments in science, make it necessary to reconsider existing strategies for the protection of the marine environment, and to propose new ones” ( 4 ) . I hope that Canada, as well as other countries, would continue to advance in the quest for a clean environment and not ignore new paradigms or approaches solely because they are difficult (e.g., ecosystemlevel studies) or expensive (e.g., sitespecific concerns). I thank Moore et al. and the many individuals who have written to comment on my article. I welcome additional constructive comment and input, Environmental quality is job one and, forgive the pun, we cannot afFORD otherwise. References (1) McKone, T. E.; Bogen, K. T. Environ. Sci. Technol. 1991, 25, 1674-81. (2) Paul, J, F. et al. In Proceedings of the
17th Annual Aquatic Toxicity Workshop; Chapman, P. M. et al., Eds.; Canadian Technical Report, Fisheries and Marine Sciences, No. 1774: Ottaw a , 1991,pp. 80-99. (3) Hahn. 1. Environ. Sci. Technol. 1991, 25, 1530-32. (4) Gray, J , S. et al. Mar. Pollut. Bull. 1991,22,432-40.
