Ecological Risk Assessment - Part 6 pps

At minimum, ecological risk sors must report the results of their risk characterization to the risk manager and anystakeholders who are involved in the decision-making process Chapter 35

Part VI

Risk Management

Risk characterization serves to inform risk management At minimum, ecological risk sors must report the results of their risk characterization to the risk manager and anystakeholders who are involved in the decision-making process (Chapter 35) In some contexts,ecologi cal risk assessors are also involv ed in the decision-m aking process (Chapter 36) To theextent that a formal analytical process is involved, risk assessors must, at least, present resultsthat support that decision analysis Because decisions are based on human health, legal,economic, ethical, and political considerations as well as ecological considerations, ecologicalrisk assessors should be prepared to help integrate all of those considerations to support therisk manager (Chap ter 37 and Chapt er 38) Once the managem ent decisio n has be en made,ecologi cal risk assessors may be invo lved in monito ring the results (Chapter 39)

asses-This part of the process of environmental assessment and management is the least fortable for most ecological risk assessors However, if they are to be successful in influencingenvironmental management, environmental scientists must be prepared to engage with thesocial sciences and deal with the politics of decision making

com-35 Reporting and Communicating

35.1 REPORTING ECOLOGICAL RISKS

The form in which ecological risks are reported is an oft-neglected aspect of the practice ofecological risk assessment The EPA’s guidance for risk characterization states that a report

of risk assessment results must be clear, transparent, reasonable, and consistent (SciencePolicy Council 2000) Consid erations for achievi ng these goals are listed in Box 35.1 Ho w-ever, the goals of being brief (for clarity) and transparent are conflicting If sufficient detail ispresented for the reader to fully understand how the results were derived and to replicatethem, the resulting multivolume report will be thicker than anyone will care to read Asdiscus sed in Chapt er 5, simply justify ing the assignmen t of dist ribut ions to parame ters mayresult in a sizable report However, some critics have advocated more complete risk charac-terizations including multiple alternative risk estimates (Gray 1994) For ecological riskassessments, this means reporting not only risk estimates for all lines of evidence in alltypes of evidence for each endpoint, but also results for alternative assumptions within aline of evidence

The usual solution to this conflict between brevity and transparency is the executivesummary Unfortunately, executive summaries attempt to summarize the entire assessmentand are seldom sufficient to stand alone if the ‘‘executive’’ is the risk manager A report ofresults that neglected methods but presented risks in adequate detail for decision makingwould probably be more useful in most cases In addition to summarizing the results, a report

to the risk manager should explain the major issues, any controversies, and relevant dents Ideally, the contents and level of detail would be worked out between the risk assessors

. Make language and organization understandable to risk managers and informed lay people

. Explain quantitative results

. Fully discuss and explain unusual issues specific to a particular risk assessment

For transparency:

. Identify the scientific conclusions separately from policy judgments

. Clearly articulate major differing viewpoints or scientific judgments

. Define and explain the risk assessment purpose (e.g., regulatory purpose, policy analysis,priority setting)

. Describe the approaches and methods used

. Explain assumptions and biases (scientific and policy) and their influence on results

For reasonableness:

. Integrate all components into an overall conclusion of risk that is complete, informative,and useful in decision making

. Acknowledge uncertainties and assumptions in a forthright manner

. Describe key data as experimental, state-of-the-art, or generally accepted scientific ledge

know-. Identify reasonable alternatives and conclusions that can be derived from the data

. Define the level of effort (e.g., quick screen, extensive characterization) along with thereason(s) for selecting this level of effort

. Explain the status of peer review

For consistency:

. Follow statutory requirements, guidelines, and precedents

. Describe how the risks posed by one set of stressors compare with the risks posed by asimilar stressor(s) or similar environmental conditions

. Indicate how the strengths and limitations of the assessment compare with past assessments

Source: Adapted from EPA (U.S.Environmental Protection Agency), Guidelines for Ecological Risk ment, EPA=630=R-95=002F, Risk Assessment Forum, Washington, DC, 1998; and Science Policy Council, Risk Characterization Handbook, EPA 100-B-00-002, US Environmental Protection Agency, Washington,

Assess-DC, 2000.

and risk manager Routine assessments, such as those for new chemicals, may have a standardform or format for reporting to the risk manager.

The needs of users other than the decision maker constitute a more serious conflict with thecall for brevity Cost–benefit analysts or decision analysts need detailed results to supporttheir analyses Risk assessments prepared by a responsible party must present data andmethods in detail so that regulators can review their acceptability Risk assessments prepared

by regulators must present data and methods in sufficient detail that the responsible party canreview their acceptability In either case, the report must be sufficiently detailed to withstandlegal scrutiny As a result, the report of a complex ecological risk assessment may fill a libraryshelf Simply providing data, models, and analytical results on a CD or DVD can help, butcreative solutions to the problem are needed The use of hypertext is promising in that itwould allow a person reading a brief summary of the risk assessment to bore into a topic tothe depth that is appropriate to interests and needs However, creating a large hypertextdocument is not quick or easy, and many people do not like to read from a computer screen.35.2 COMMUNICATING ECOLOGICAL RISKS

Risk communication is the process of conveying the results of risk assessments to decisionmakers, stakeholders, or the public, and of receiving and responding to their comments.(Some documents define risk communication to include consultation during planning andproblem formulation.) It goes beyond the issue of reporting the results of the risk assessment

in a clear and useful manner to actually conveying the results to a skeptical audience It isdifficult for two reasons First, like any quantitative and scientific subject, it is difficult toconvey to those who do not have the requisite training or experience Risk assessments may

be particularly difficult to explain, because they combine biological and physical sciences withmathematics and statistics Second, situations that require risk assessments are often emo-tionally charged People’s health, livelihood, and property values are typically at stake, anddistrust is typically high Most of the literature of risk communication is directed at issues ofmanaging emotions and gaining trust with respect to health risks, independent of the nature

or quality of the technical message (NRC 1989; Fisher et al 1995; Lundgren and McMakin1998) Those issues will not be treated here, because emotional investment in ecological issues

is usually lower and is likely to be qualitatively different In many if not most ecological riskassessment cases with high levels of emotional investment, such as restrictions on harvesting,water withdrawals, or land use to protect resource species or endangered species, the issuesare largely economic and the strong emotions are largely held by those who generate the risk.Fishermen, loggers, ranchers, and farmers are reluctant to believe that their activities damagethe environment in ways that would justify restriction of their activities Research is needed toguide risk communication in such situations

The technical communication problems are more severe for ecological risk assessors thanfor health risk assessors Ecological risk assessors not only deal with unfamiliar scientific andmathematical concepts, but also often estimate risks to unfamiliar entities and attributes.Decision makers and stakeholders know full well what a human is and have both knowledge

of, and empathy for, the various fates that befall humans However, many will not know what

a spectacled eider or an Atlantic white cedar bog is, much less the implications of changes intheir nesting success or in hydro-period Humans have a sense of their own inherent value andtheir value to their family and community, but have little knowledge or appreciation ofequivalent values of ecological entities Hence, much of ecological risk communication is amatter of education This education may require a little honest salesmanship as well as thebasic description of an entity and attribute This may involve the use of attractive photo-

environment should not occur because the decision makers lack a vivid understanding ofwhat may be lost or gained.

A related communication problem is the greater familiarity of most decision makers withthe relatively simple methods and results of human health risk assessments The numerousendpoints and multiple types of evidence employed in ecological risk assessments make themseem complex and ambiguous This problem may be alleviated as health risk assessmentsbegin to use multiple lines of evidence and to estimate the range of public health outcomes.However, in the meantime, decision makers tend to focus on aspects of ecologicalrisk assessment that seem familiar As a result of that tendency and the natural affinity

of people for mammals and birds, risks expressed in the familiar terms of effects onsurvival or reproduction of such species tend to be inordinately influential For other end-points, it is important to explain not only what they are and how they respond but also whythey are assessed using unfamiliar methods and models As far as possible, use analogies tohealth risk assessment For example, analyses of biological survey data in risk assessmentscan be described as ecological epidemiology, and species sensitivity distributions can bedescribed as dose–response models for ecological communities Finally, the unfamiliarity ofecological methods and models often leads decision makers to ask whether they are officialmethods or have been used previously in decision making Therefore, it is important to beprepared to cite guidance and precedents If a genuinely novel method or model is used, beprepared to compare its results to those of more familiar methods or models and to explainthe advantages of the innovation

A more pervasive problem is the inherent difficulty of conveying scientific and ical concepts to people who are not trained in those fields As Cromer (1993) explains, science

mathemat-is difficult to do and to convey, because it constitutes uncommon sense It has been suggestedthat this is because the human mind evolved to extrapolate directly from experience, whichworks routinely but results in flawed logic in complex or unfamiliar inferences (Pinker 1997;Dawes 2001) Further, even when reasoning carefully, the mind deals more easily with somesorts of information and problems than others (Pinker 1997; Anderson 1998, 2001) Fromthese generalizations, some advice can be derived

Avoid probabilities: People, including scientifically trained experts, have difficulty withprobabilities, but understand and manipulate frequencies relatively easily (Gigerenzer andHoffrage 1995; Gigerenzer 2002) Whenever possible without distorting the results, translateprobabilities to frequencies when communicating risks This has the ancillary advantage offorci ng you to de termine exactly what you mean by a probab ility (Ch apter 5)

Use discrete units: Although most properties of nature are continuous, the mind divides thecontinua of time and space into events and objects For example, Bunnell and Huggard (1999)reduced the spatial continuum of forests to a hierarchy of units (patches, stands, landscapes,and regions), which could be more easily described to forest managers than sets or areas offorest

Use categories: We not only discretize continuous variables, but also lump the units intolike categories to which we assign names Hence, ‘‘folk biology is essentialistic’’ (Pinker 1997).Long after ecology has revealed the variance in species composition over space, we continue

to name vegetation and ecosystem types (e.g., mixed mesophytic forest) Similarly, it is ofteneasier to communicate the frequencies of categories (e.g., high, moderate, or low) associatedwith ranges of a continuous variable (e.g., flow) than to communicate the meaning of thevariable’s probability density

Use few categories: People tend to divide entities or events into only two or three categoriessuch as drought, normal, and flood for flow regimes

Tell stories: Information imbedded in a narrative is more convincing and rememberedlonger Every conceptual model is a potential story

Use multiple modes: Individual audience members will respond differently to verbal, grammatic, pictorial, or other modes of representation By using multiple modes of presen-tation you are more likely to achieve comprehension with one In particular, photographs ofthe effects being discussed such as photos comparing plants grown in site and reference soils

dia-or depictions of the diversity of fish species in a disturbed and reference stream can makeunfamiliar effects vivid In addition, repetition increases comprehension and retention andrepetition using multiple modes avoids boredom Similarly, in presentations it is advanta-geous to include speakers with different styles to engage the diverse members of the audience.Use case studies: Even if your assessment is generic (e.g., national risks from mercury incoal combustion emissions), illustrate it with a particular case (e.g., loons in the boundarywaters) People are more willing to extrapolate from one real case to many than from anabstraction to any real case

Simplify carefully: Scientific concepts can be complex and difficult It is often advantageous

to use a simple analogy to convey a complex system However, it is important to preparequalifiers (e.g., of course it is not really that simple), because knowledgeable members of theaudience, particularly those who are opponents, will pounce on an ‘‘oversimplification’’(Schneider 2002)

Remember the human analogy: While you are talking about risks to otters from eating fish,many in the audience will be thinking about what it implies for people eating fish Be preparedfor the questions that such analogies imply and avoid statements that would alarm those whoare focused on the human analogy or that contradict the human health risk assessment.Avoid personalizing: Although personalizing a situation makes the message more vivid (e.g.,

‘‘I would not let my daughter eat fish from that river’’), it is a bad strategy for risk assessors.Present the results of your analysis and let the risk managers and stakeholders infer thepersonal implications

Of course, this advice is superceded by the advice to know your audience For example,former US EPA administrator Ruckleshaus (1984) preferred that risk assessment results bepresented as cumulative distribution functions, contradicting some of the previous advice.This example also serves to remind assessors not to talk down to risk managers, stakeholders,

or the public An individual who is not an environmental scientist and does not know whatBayesian means or what a Pimephales promelas is should not be treated as unintelligent Acondescending or contemptuous attitude will be detected and will result in dismissal of yourmessage On the contrary, people can understand and appreciate descriptions of complexnatural systems if they are well presented The renowned conservation biologist DanielJanzen has said of ecological complexity: ‘‘Audiences soak it up I was told that it’s toocomplicated and a lot of people won’t understand it Bullshit They understand it perfectlywell’’ (Allen 2001)

Risk communication is an opportunity to ensure that your efforts do some good Theaudience is less likely to be hostile than in human health risk communication Becauseecological risks are not personal threats, audiences are open to learning a bit about natureand how plants and animals interact with contamination or disturbance You have anopportunity not only to explain your results but also to educate and even entertain In thatway, you can help to create a constituency for good ecological management

36 Decision Making and Ecological Risks

It is not industry, development or the nation’s growing population that poses the greatest threat

to the environment, it is shortcomings in the political process that perpetuate environmentaldegradation

Howard R Ernst (2003)

In the conventional environmental and ecological risk assessment frameworks, risk assessorscommunicate their results to risk managers and then leave the room Decision making isviewed as a policy-based and science-informed political process that is best left to those whohave political authority This description is accurate in many cases However, to clarifytechnical issues and avoid misunderstanding, risk assessors may be, and should be, involved

in the decision-making process In some cases, distinct analyses are performed after therisk assessment and before the decision by economists or experts on decision analysis Insuch cases, risk assessors are likely to be involved in supporting or helping to performthose analyses In addition, even when risk assessors are not involved, they should havesome understanding of the decision-making process so that their results may be as useful aspossible and to avoid unrealistic expectations about their ability to determine the outcome.The bases for decision making discussed in this chapter are limited to those that are risk-related As discus sed in Chapt er 2, so me environm ental de cisions are made based on bestavailable technology or some other criterion that does not include risk It must be borne inmind that politics is the ultimate criterion Any of the decision criteria discussed below may beoverridden by political ideology or political expediency

36.1 PREVENTING EXCEEDENCE OF STANDARDS

The simplest and least ambiguous decision criterion is that if an environmental standard isviolated, action must be taken To the extent that standards are based on ecological risks(Chap ter 29), these are risk- based decision s

36.2 PREVENTING ADVERSE EFFECTS

The national policy of the Netherlands states that exposure to substances should not result inadverse effects on humans or ecosystems (VROM 1994) Similarly, the US Clean Water Actprohibits ‘‘impairment of the physical, chemical, or biological integrity of the Nation’swaters.’’ Such policies provide the most clearly risk-based criteria for decision making.Given a definition of adverse effects, one can determine whether they are expected to occur

or whether the probability of occurrence is excessive, and that is sufficient grounds for action

36.3 MINIMIZING RISKS

Com parative risk assessment s (Ch apter 33) provide a basis for decision makers to ch oose theacti on that present s the least risk to human health or the e nvironm ent Com parative riskestimat es can be based on a techni cal risk charact erization as discus sed in Chapter 33.Alternat ivel y, it can be viewed more broad ly as a type of policy an alysis that includes relativerisks a nd psychosoci al preferen ces co ncerning different types of risks in a process of stake-holder consensus buildin g That approach can be thought of as a microscal e a pplication to aspecif ic decision of the macros cale pr ocess of using compara tive risk asses sment for prioritysetting (Sect ion 1.3.1) (Andr ews et al 2004)

36.4 ASSURING ENVIRONMENTAL BENEFITS

Often, eithe r expli citly or impl icitly, actions to protect the environm ent are judged to bedefensi ble if they are exp ected to resul t in adeq uate benefi ts to the environm en t Bene fits arethe complem ent of ad verse effe cts an d their risks In the context of risk assessment , benefitsare avoidanc e of a risk of adverse effe cts In the context of remediati on and restorati on, risksare the probabil ities that ben efits will not be realized or that damage will occur due to poorplanning or executio n, or chance events Bene fits may be judged in term s of absolute benefi ts

of an action, relative be nefits of alternati ve actions (Sect ion 33.1 5), or be nefits relat ive tocosts (Section 36.6)

Concer ns for the benefi ts of actio ns may be express ed when a program has been ong oingfor some time, costs have be gun to mount, an d questio ns arise abou t the cost-eff ectiven ess ofthe expend itures An examp le is the exp enditur e of $580 milli on on 38 pro jects to remediatecon taminate d sedim ents in the Laur entia n Great Lake s witho ut a clear linkag e to increa ses inben eficial uses (Za rull et al 1999) At some point, faith in su ch large exp enditur es failswithou t evidence of benefits As a resul t, the Great Lakes Water Qual ity Boar d reco mmendedthe de velopm ent of be tter method s to qua ntify the relationshi p be tween sed iment co ntamin-ation and use impai rment s, and to mon itor the ecologi cal be nefits and bene ficial uses ofremedi ated sites

36.5 MAXIMIZING COST-EFFECTIVENESS

Cost e ffectiven ess an alysis identifi es the relative moneta ry costs of diff erent mean s of ach ing a standar d, an a cceptable risk level, or other goal The decisio n maker co uld then choosethe least-cos t method A v ariant of this idea that ha s had impor tant environm ental impl ica-tions in the Un ited States is the principles and guidelines framew ork of the Army Corps ofEngin eers which maximize s the net nationa l econ omic benefi ts of project alternati ves, as long

iev-as they do not cau se signi ficant environm ental deg radation (USA CE 1983)

36.6 BALANCING COSTS AND BENEFITS

Cost–b enefit an alysis is increa singly ap plied to environm ental regula tory and remedial tions The decisi on mod el is that the public benefits of regula tions should exceed the c osts ofcompliance to the regulated parties In some cases, it is sufficient to show that monetary andnonmonetary benefits qualitatively balance the costs However, strict interpretations of cost–ben efit requir ements allow only mon etary be nefits As discus sed in Sectio n 38.3, this require-ment to monetize the benefits of ecological entities and processes can be a serious impediment

ac-to environmental protection

36.7 DECISION ANALYSIS

Decision analysis comprises a diverse set of concepts and methods for informing a decision.Classic formal methods define the decisions to be made, the alternatives, goals, possibleoutcomes, their values to the decision maker (utility metrics), and their probabilities so as

to calculate the expected value or utility of each alternative (Clemen 1996) An early example

of an environmental application of formal decision analysis is an analysis of further research

vs remedial alternatives for polychlorinated biphenyl (PCB)-contaminated Salt Creek, ana (Parkhurst 1984) Other methods are less quantitative, less focused on quantifying theexpected consequences, and more focused on clarifying the decision for the decision maker orstakeholders In general, they include more considerations than the other decision-makingapproaches discussed in this chapter, and, because they do not require monetizing thedecision criteria, decision analyses can include noneconomic criteria (Stahl et al 2002).Utilities may be scaled in standard categories (e.g., low, medium, or high) or in terms of anenvironmental goal (e.g., hectares of wetland or abundance of game fish)

Indi-Although decision analysis has a large literature and commercial software for its mentation, it is rarely used in environmental regulation or management In part, this isbecause the explicit inclusion and quantification of considerations other than risk is likely

imple-to anger some stakeholders (Hattis and Goble 2003) Also, decision makers have littleincentive to go through the trouble of formal decision analysis when they have been successfulusing precedents and their own judgment

The US Army Corps of Engineers has begun to use multicriteria decision analysis tosupport decisions concerning the management of contaminated sediments (Linkov et al.2006) In an example from the Cocheco River, New Hamshire, the alternatives for sedimentdisposal were cement manufacture, flowable fill, wetland restoration, and upland disposalcell The multiple criteria were cost, environmental quality, ecological habitat, and humanhabitat A mail survey of stakeholders provided weights for the criteria that could becombined to produce a multicriteria score for each alternative This sort of decision analysisserves primarily to inform the decision maker about preferences of stakeholder groups based

on a structured elicitation process rather than the usual stakeholder meetings

36.8 MISCELLANEOUS AND AD HOC CONSIDERATIONS

Many, if not most, environmental management decisions are made without any explicitcriteria or any formal analysis of how the alternatives relate to criteria Decision makersconsider the information concerning risks, benefits, and costs, they may consult with stake-holders, they pay particular attention to legal and regulatory constraints and precedents, thenthey test the political winds, consult their gut, and make a decision

37 Integration of Human Health Risk Assessment

People are the probl em, but any solution which does not serve peop le will fail

M arty Matl ock (unpubli shed present ation)Inevitab ly, when both human health and the environm ent are threatened by a commonhazard, human health concern s dominat e asses sment and decisi on-maki ng pro cesses Eco-logic al risk asses sors can use the concern for hum an health to their advantag e by usingwildlife as senti nels for health effec ts, by integ rating the ecological assessment with the healt hasses sment so as to combine resourc es, and by sh owing how ecologi cal effe cts influencehuman healt h and welfar e

37.1 WILDLIFE AS SENTINELS

Wildlif e may serve as sentinels, thereby stre ngtheni ng the case for current or futur e risks tohumans (NRC 1991; Burk hart and Gardne r 1997; Peter 1998; Sheffield et al 1998; van derSchali e et al 1999; Col born an d Thay er 2000; Fox 2001) An exa mple of wildlife a s sentinels isthe obs ervation of thyroi d patho logy in wildli fe due to halogenat ed organic chemi cals that led

to studies in hum ans (Fox 2001; Karmau s 2 001) How ever, most report s of the use of an imalsentin els of he alth effects have not provided the types and levels of e vidence ne eded beforehealt h decisio ns can be based on sen tinel responses (Ra binowitz et al 2005) Althou gh thereare diff iculties in extra polating from wildlife to humans (Stahl 1 997), they are conc eptually nomore severe than those associated with extra polating from labo ratory rats to humans.Wildlife species are likely to be effective sentinels if they have a common source and route

of exposure with humans but are more exposed, more sensitive, or more readily monitored.They are, in general, likely to be more exposed and therefore likely to respond more quicklyand severe ly than huma ns (Bo x 2.1) In general , the use of wildli fe as sentinels may be just ified

by the following factors:

Common routes: Wildlife may feed on the same organisms as humans, particularly in thecase of piscivorous wildlife and subsistence or recreational fishermen Similarly, wildlife mayconsume contaminated soil, as do children

Stenophagy: Wildlife species are generally less omnivorous than humans and thereforespecies that consume a contaminated food item are likely to be more exposed

Local exposure: Wildlife species do not obtain food or water from outside their home range,

so they are more exposed to contaminated locations

Same mixture: Wildlife species are exposed to the same mixture of contaminants as humansliving in, or consuming foods from, the same contaminated system