MODERN BIOGEOCHEMISTRY: SECOND EDITION Phần 1 doc

Integration of risk assessment and environmental impact assessment 4.. Critical Load and Level CLL approach for assessment of ecosystem 1.. Definitions in risk assessmentare all-importan

MODERN BIOGEOCHEMISTRY

Second Edition

Environmental Risk Assessment

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ABOUT THE AUTHOR

Vladimir N Bashkin was born in 1949 in the town of Dobrinka, Lipetsk region,

Russia He graduated from the Biology-Soil department of Moscow State University

in 1971, where in 1975 he was awarded a PhD, and in 1987, a Doctor of Science degree.His scientific career began at the Pushchino Biological Center of the Russian Academy

of Sciences in 1971 For many years Vladimir Bashkin delivered lectures in variousuniversities such as Cornell University, USA, Seoul National University, Korea, andKing Mangkut’s University of Technology, Thailand At present he is a professor ofbiogeochemistry and risk assessment at Moscow State University, and the principalresearcher at the Gazprom company and Institute of Basic Biological Problems RAS.His main research is related to environmental risk assessment, biogeochemistry, urbanecology, and trans-boundary pollution Professor Bashkin is the author of 22 books,including Modern Biogeochemistry and Environmental Chemistry: Asian Lessons(published by Kluwer), and more than 100 papers Under his supervision more than 20PhD and DrSc dissertations have been presented in various countries and universities

He is a member of the board of five international journals in the field of environmentalpollution During a five year period he was selected as vice-chairman of the WorkingGroup of Effects (scientific committee) of the UN/EC Long-Range Trans-boundaryAir Pollution Convention

v

PART I BIOGEOCHEMICAL CYCLING AND POLLUTANTS

EXPOSURE

1 Concepts of environmental impact assessment and risk assessment

2 Biogeochemical approaches to environmental risk assessment 6

3 Integration of risk assessment and environmental impact assessment

4 Assessment of ecosystem effects in EIA: methodological promises

5 Critical Load and Level (CLL) approach for assessment of ecosystem

1 Characterization of soil-biogeochemical conditions in the world’s

2 Biogeochemical classification and simulation

2.2 Methodology of biogeochemical cycling simulation for biosphere

3 Biogeochemical mapping for environmental risk assessment

3.2 Regional biogeochemical mapping of North Eurasia 46

1 Critical load as biogeochemical standards for acid-forming chemical

vii

viii CONTENTS

1.1 General approaches for calculating critical loads 481.2 Biogeochemical model profile for calculation of critical loads

1.3 Deriving biogeochemical parameters for critical loads of acidity 52

2 Critical load as biogeochemical standards for heavy metals 582.1 General approaches for calculating critical loads of heavy metals 592.2 Deriving biogeochemical parameters for critical loads of heavy

2.3 Calculation methods for critical loads of heavy metals 68

CHAPTER 4 BIOGEOCHEMICAL APPROACHES TO ECOSYSTEM

1 Environmental risk assessment under critical load calculations 751.1 Suggested ERA frameworks and endpoints for development of

1.2 Comparative analysis of CL and ERA calculations of acidification

CHAPTER 5 BIOGEOCHEMICAL APPROACHES TO HUMAN

pollution in the Crimea Dry Steppe region of the biosphere 116

PART II NATURAL BIOGEOCHEMICAL PECULIARITIES

OF EXPOSURE ASSESSMENT

1 Geographical peculiarities of biogeochemical cycling and pollutant

1.2 Pollutant exposure and chemical composition of plants 129

CONTENTS ix

2 Biogeochemical cycles and exposure assessment in polar zones 131

3 Biogeochemical cycles and exposure assessment in tundra zones 133

3.3 Exposure to pollutants and productivity of tundra ecosystems 134

1 Biogeochemical cycling of elements and pollutants exposure

2 Geographical peculiarities of biogeochemical cycling and pollutant

2.2 Spruce Forest ecosystem of Northwestern Eurasia 147

2.4 Broad-leafed deciduous forest ecosystems of Central Europe 154

3 Biogeochemical fluxes and exposure pathways in soil–water system

3.2 Biogeochemical exposure processes in the soil–water system 160

1 Biogeochemical cycling of elements and pollutants exposure in

1.1 Biogeochemical cycle and exposure pathways in arid ecosystems 1671.2 Role of aqueous and aerial migration in pollutants exposure 1681.3 Role of soil biogeochemistry in the exposure pathways

2.2 Meadow steppe ecosystems of the East European Plain 175

1 Biogeochemical cycling of elements and pollutants exposure in

2.2 Biogeochemical cycling and pollutant exposure in Seasonal

Deciduous tropical forest and woody savanna ecosystems 1892.3 Biogeochemical cycling and pollutant exposure in dry desert tropical

2 Geological and biological factors of oil composition formation 203

3 Peculiarities of ecological risk assessment in oil

3.3 Spatial and temporal evolution of oil pollution areas 2103.4 Biogeochemical feature of environmental risk assessment 214

1.1 Heavy metal migration in biogeochemical food webs 2161.2 Sources of heavy metals and their distribution in the environment 218

3 Technobiogeochemical structure of metal exploration areas 224

CONTENTS xi

4 Modern approaches to exposure assessment in urban areas 231

1 Impact of agrochemicals on the natural biogeochemical cycling 245

1.2 Disturbance of nitrogen biogeochemical cycle in agrolandscapes 2461.3 Disturbance of phosphorus biogeochemical cycle in agrolandscapes 247

PART IV ENVIRONMENTAL RISK ASSESSMENT

IN A REGIONAL SCALE

2.2 Characterization of the composition of personal, indoor, and

1 Environmental risk assessment of Se induced diseases 275

2 Environmental risk assessment of Co–Zn–Ni induced diseases 280

xii CONTENTS

2.1 Biogeochemical cycles of heavy metals in the South Ural region,

2.2 Endemic diseases biogeochemical exposure pathways 283

3 Environmental risk assessment of air pollution induced diseases 2833.1 Estimating and valuing the health impacts of urban air pollution 283

1.4 Agricultural, industrial, and municipal waste discharges 298

1.7 Environmental legislation and regulation in respect to ERA 300

2.4 Environmental risk assessment of organochlorine species 309

3 Conceptual model for the environmental risk assessment of

3.3 Other factors increasing POCs environmental risk 315

1 Assessment of environmental risk to acid deposition in

2.3 Wet deposition of sulfate in eastern North America 3312.4 Ecological impacts of acid deposition in Eastern North America 3332.5 The impact-oriented critical load approach to SO2emission

CONTENTS xiii2.6 Sulfur dioxide emission abatement scenario in North America

3 Assessment of environmental risk to acid deposition in Asia 3433.1 Characterization of environmental conditions in Asia 343

3.3 Critical load values of acid-forming compounds on ecosystems

3.4 Critical loads of sulfur and acidity on Chinese ecosystems 350

3.6 Acid deposition influence on the biogeochemical migration of

4 Assessment of heavy metal pollution in the Northern hemisphere

1 Evaluation of POPs deposition in the European countries 385

1.4 Spatial pattern of PCDD/Fs contents in various

1.5 Trans-boundary pollution in the European domain 391

xiv CONTENTS

2.1 Priority POPs and their permissible levels in soil 393

2.3 Evaluation of POP accumulation and clearance in soil 399

3 Exposure pathways of dioxins and dioxin-like polychlorinated

3.2 Potential for long-range trans-boundary air pollution 403

2.1 Critical load approach for assessing environmental risks 414

2.3 Exceedances of critical loads of pollutants in the ecosystems

to examine risks of very different natures For instance, the approach is used to assessthe environmental risks posed by Genetically Modified Organisms (GMOs), chemi-cals, ionizing radiation and specific industrial plants Definitions in risk assessmentare all-important because of the wide range of uses of the approach, and differentmeanings of terms used by different groups of experts and practitioners.

The concept of Environmental Risk Assessment (ERA) is based on the chemical principles of sustainability of natural and technogenic ecosystems and ap-plies the methods of biogeochemistry, geoecology, human physiology, applied math-ematics and theory of probabilities and uncertainty, economics, statistics, sociology,toxicology, environmental chemistry and other disciplines The quantitative estimate

biogeo-of ecological risk can be the principal link in the chain biogeo-of ecological safety factor forthe whole of society Taking into account the modern regional and global statistics oftechnogenic accidents and catastrophes as well as environmental pollution, in manydeveloped and developing countries the ERA calculations are of great importanceand interest for governmental and private institutions

At present quantitative ecological risk assessment is widely used in different tings, however very often without an understanding of the natural mechanisms thatdrive the processes of environmental and human risk and complicated by a highuncertainty of risk values On the other hand, the sustainability of modern technoe-cosystems is known, based on their natural biogeochemical cycling that is transformed

set-to various extents by anthropogenic activities Accordingly an understanding of theprincipal mechanisms driving the biogeochemical food webs allows us to describethe quantitative ecological risk assessment and to propose technological solutions forERA management in various contents The same is true for insurance of ecologicalrisks that is the powerful mechanism of a protection of responsibility rights and amanagement of ecological damage owing to natural and anthropogenic accidents andcatastrophes

This book is aimed at generalizing the modern ideas of both biogeochemical andenvironmental risk assessment during recent years Only a few books are available for

xv

xvi PREFACE

readers in this interdisciplinary area, however, as most books deal mainly with varioustechnical aspects of ERA description and calculations This text aims at supplementingthe existing books by providing a modern understanding of mechanisms that areresponsible for ecological risks for human beings and ecosystems

This book is to a certain extent a summary of both scientific results of various thors and of classes in biogeochemistry and ERA, which were given to students by theauthor during recent years in different universities So I would like to thank the manystudents of the Universities of Cornell, Moscow, Pushchino, Seoul, and Bangkok,who explored this subject initially without a textbook The critical discussion andcomments during these classes have provided me the possibility of presenting thisbook

au-I am also thankful to my international colleagues whose various cooperative resultswere used in this text, Prof R.W Howarth, Prof N Kasimov, Prof E Evstafyeva,Prof H.-D Gregor, Prof J.-P Hettelingh, Mr S Dutchak, Prof S-U Park, Dr S.Tartowski, Dr A Kazak, Dr R Galiulin, Dr I Priputina, Dr M Kozlov, Dr G.Vasilieva, Dr D Savin, Dr O Demidova, Dr I Ilyin, Dr E Mantseva, Dr V Shatalov,

Dr S Towprayoon and many others

Vladimir N Bashkin

Professor

Moscow State University

Institute of Basic Biological Problems RAS

PART I

BIOGEOCHEMICAL CYCLING AND POLLUTANTS EXPOSURE

CHAPTER 1

ASSESSMENT OF ECOSYSTEMS RISKS

Over the last decades direct and indirect environmental effects of human activitieshas become a focus of special attention of the general public, state authorities, andinternational organizations A number of approaches to predict, evaluate, and mitigatehuman-induced alterations in the biophysical environment have emerged includingenvironmental impact assessment (EIA) EIA has become a powerful tool to preventand mitigate environmental impacts of proposed economic developments

In the current EIA practice, impacts on natural systems (ecological effects) areoften given less attention than they deserve (Treweek, 1999) One of the key reasons

is a great deal of uncertainty associated with ecological impact studies

Meanwhile, there has arisen a well established methodology for assessing opments in the face of a high degree of uncertainty and establishing the potentiallyhigh significance of impacts, we call this methodologyrisk assessment (RA) including environmental risk assessment (ERA) Recent interest in “tools integration” (Sheate,

devel-2002) is related to growing debate on the benefits of integrating RA into EIA dures in terms of improving treatment of impacts of concern (see, e.g., Andrews, 1990;Arquiaga et al., 1992; NATO/CCMS, 1997; Poborski, 1999) A number of proceduraland methodological frameworks for EIA–RA integration has already been proposedand many researchers believe that RA should be used extensively in assessment s formany types of impacts including impacts on ecosystems (Lackey, 1997)

proce-Ecological impact assessment induced by various human activities is a focal point

of improving methodology for environmental impact assessment Although there is anestablished methodology for assessing EIA, it is applied mainly in anad hoc manner

(Eduljee, 1999) Moreover, there is a vocal critique on applicability of ERA ology to studies of ecosystem effects of proposed development (Lackey, 1997) Thestate-of-art ecological risk assessment (EcoRA) has established tools and techniquesfor and provides credible findings at species level investigations Recent develop-ments in ERA methodology allowed the researcher to move to population and evencommunity level assessments (see Smrchek and Zeeman (1998) for details) At thesame time, formal EcoRA is sometimes focused on effects on groups of organisms,and not an ecosystem as a whole RA at ecosystem level is usually comparative andqualitative (Lohani et al., 1997)

method-Meanwhile, a quantitative approach to assessing pollution effects on ecosystemshas already been developed A Critical Load and Level (CLL) concept has beenused for defining emission reduction strategies under the UNECE Convention on

3

4 CHAPTER 1

Long-range Transboundary Air Pollution (LRTAP) Over time, the critical load proach has been defined not only at international but also at regional and local levels(Posch et al., 1993, 1997, 1999, 2001, 2003; Bashkin, 1997, 2002)

ap-Accordingly, this chapter discusses the incorporation of the CLL concept into EIAfor assessment and management of risks for natural ecosystems The authors aimed

at providing insights on applying this effect-oriented approach within a legally lished procedure for assessing proposed economic developments The proponents areencouraged to consider the CLL methodology as a promising tool for cost-effectiveimpact assessment and mitigation (Posch et al., 1996)

estab-The first section explains the concepts of EIA and RA and the existing approaches

to their integration This is followed by an analysis of the current situation with logical input into EIA and discussion on how the formal EcoRA framework providesfor site-specific ecosystem risk assessment The subsequent section reviews the CLLapproach and its applicability for assessing ecological effects in EIA Finally, a modelfor assessment of ecosystem risks within EIA using the CLL approach is proposed

eco-1 CONCEPTS OF ENVIRONMENTAL IMPACT ASSESSMENT AND RISKASSESSMENT AND APPOACHES TO THEIR INTEGRATIONThe technique of risk assessment is used in a wide range of professions and aca-demic subjects Accordingly, in this introductory section some basic definitions arenecessary

Hazard is commonly defined as “the potential to cause harm” A hazard can bedefined as “a property or situation that in particular circumstances could lead to harm”(Smith et al., 1988) Risk is a more difficult concept to define The term risk is used

in everyday language to mean “chance of disaster” When used in the process ofrisk assessment it has specific definitions, the most commonly accepted being “Thecombination of the probability, or frequency, of occurrence of a defined hazard andthe magnitude of the consequences of the occurrence” (Smith et al., 1988)

The distinction between hazard and risk can be made clearer by the use of asimple example A large number of chemicals have hazardous properties Acids may

be corrosive or irritating to human beings for instance The same acid is only a risk tohuman health if humans are exposed to it The degree of harm caused by the exposurewill depend on the specific exposure scenario If a human only comes into contactwith the acid after it has been heavily diluted, the risk of harm will be minimal butthe hazardous property of the chemical will remain unchanged

There has been a gradual move in environmental policy and regulation fromhazard-based to risk-based approaches This is partly due to the recognition thatfor many environmental issues a level of zero risk is unobtainable or simply notnecessary for human and environmental protection and that a certain level of risk in

a given scenario is deemed “acceptable” after considering the benefits

Risk assessment is the procedure in which the risks posed by inherent hazardsinvolved in processes or situations are estimated either quantitatively or qualita-tively In the life cycle of a chemical for instance, risks can arise during manufacture,

ASSESSMENT OF ECOSYSTEMS RISKS 5distribution, in use, or the disposal process Risk assessment of the chemical involvesidentification of the inherent hazards at every stage and an estimation of the risksposed by these hazards Risk is estimated by incorporating a measure of the likeli-hood of the hazard actually causing harm and a measure of the severity of harm interms of the consequences to people or the environment.

Risk assessments vary widely in scope and application Some look at single risks

in a range of exposure scenarios such as the IPCS Environmental Health CriteriaDocument series, others are site-specific and look at the range of risks posed by aninstallation

In broad terms risk assessments are carried out to examine the effects of an agent

on humans (Health Risk Assessment) and ecosystems (Ecological Risk Assessment).Environmental Risk Assessment (ERA) is the examination of risks resulting fromtechnology that threaten ecosystems, animals and people It includes human health riskassessments, ecological or ecotoxicological risk assessments, and specific industrialapplications of risk assessment that examine end-points in people, biota or ecosystems.Many organizations are now actively involved in ERA, developing methodologiesand techniques to improve this environmental management tool Such organisationsinclude OECD, WHO and ECETOC One of the major difficulties concerning the use

of risk assessment is the availability of data and the data that are available are oftenloaded with uncertainty

The risk assessment may include an evaluation of what the risks mean in practice tothose effected This will depend heavily on how the risk is perceived Risk perceptioninvolves peoples’ beliefs, attitudes, judgements and feelings, as well as the wider so-cial or cultural values that people adopt towards hazards and their benefits The way inwhich people perceive risk is vital in the process of assessing and managing risk Riskperception will be a major determinant in whether a risk is deemed to be “acceptable”and whether the risk management measures imposed are seen to resolve the problem.Risk assessment is carried out to enable a risk management decision to be made

It has been argued that the scientific risk assessment process should be separated fromthe policy risk management process but it is now widely recognised that this is notpossible The two are intimately linked

Risk management is the decision-making process through which choices can bemade between a range of options that achieve the “required outcome” The “requiredoutcome” may be specified by legislation using environmental standards, may be de-termined by a formalized risk–cost–benefit analysis or may be determined by anotherprocess for instance “industry norms” or “good practice” It should result in risks beingreduced to an “acceptable” level within the constraints of the available resources.Risks can be managed in many ways They can be eliminated, transferred, retained

or reduced Risk reduction activities reduce the risk to an “acceptable” level, derivedafter taking into account a selection of factors such as government policy, industrynorms, and economic, social and cultural factors

It is important to note that although risk assessment is used extensively in ronmental policy and regulation it is not without controversy This is also true for riskmanagement

been firstly developed in order to calculate the deposition levels at which effects

of acidifying air pollutants start to occur A UN/ECE (United Nations/EconomicCommittee of Europe) working Group on Sulfur and Nitrogen Oxides under Long-Range Transboundary Air Pollution (LRTAP) Convention has defined the criticalload on an ecosystem as: “A quantitative estimate of an exposure to one or more pollutants below which significant harmful effects on specified sensitive elements of the environment do not occur according to present knowledge” (Nilsson and Grennfelt,

1988) These critical load values may be also characterized as “the maximum input

of pollutants (sulfur, nitrogen, heavy metals, POPs, etc.), which will not introduce harmful alterations in biogeochemical structure and function of ecosystems in the long-term, i.e., 50–100 years” (Bashkin, 1999).

The term critical load refers only to the deposition of pollutants Threshold

gaseous concentration exposures are termedcritical levels and are defined as centrations in the atmosphere above which direct adverse effects on receptors such

“con-as plants, ecosystems or materials, may occur according to present knowledge”.

Correspondingly, transboundary, regional or local assessments of critical loadsare of concern for optimizing abatement strategy for emission of polutants and theirtransport (Figure 1)

Figure 1 Illustration of critical load and target load concepts.

ASSESSMENT OF ECOSYSTEMS RISKS 7The critical load concept is intended to achieve the maximum economic benefitfrom the reduction of pollutant emissions since it takes into account the estimates ofdiffering sensitivity of various ecosystems to acid deposition Thus, this concept isconsidered to be an alternative to the more expensive BAT (Best Available Technolo-gies) concept (Posch et al., 1996) Critical load calculations and mapping allow the cre-ation of ecological–economic optimization models with a corresponding assessment

of minimum financial investments for achieving maximum environmental protection

In accordance with the above-mentioned definition, a critical load is an tor for sustainability of an ecosystem, in that it provides a value for the maximumpermissible load of a pollutant at which risk of damage to the biogeochemical cy-cling and structure of ecosystem is reduced By measuring or estimating certain links

indica-of biogeochemical cycles indica-of sulfur, nitrogen, base cations, heavy metals, variousorganic species and some other relevant elements, sensitivity both biogeochemicalcycling and ecosystem structure as a whole to pollutant inputs can be calculated, and

a “critical load of pollutant”, or the level of input, which affects the sustainability ofbiogeochemical cycling in the ecosystem, can be identified

3 INTEGRATION OF RISK ASSESSMENT AND ENVIRONMENTAL

IMPACT ASSESSMENT FOR IMPROVED TREATMENT

OF ECOLOGICAL IMPLICATIONSEIA is a process of systematic analysis and evaluation of environmental impacts

of planned activities and using the results of this analysis in planning, authorizingand implementation of these activities Incorporation of environmental considera-tions into project planning and decision-making has become a response to growingpublic concern of potential environmental implications of economic activities Overthe last decades EIA has become a legally defined environmental management toolimplemented in more than 100 countries worldwide (Canter, 1996)

A generic model of the EIA process includes such distinct stages as screening,scoping, impact prediction and evaluation, mitigation, reporting, decision-making,and post-project monitoring and evaluation (EIA follow-up) with public participationand consideration of alternatives potentially incorporated at all stages of the process(Wood, 1995; Canter, 1996; Lee and George, 2000)

A special assessment procedure that aims at tackling uncertain consequences ofhuman activities is called risk assessment (RA) The main objective of risk assessment

is to use the best available information and knowledge for identifying hazards, ing the risks and making recommendations forrisk management (World Bank, 1997).

estimat-Traditionally, RA has been focused on threats to humans posed by industrialpollutants In recent times there has been a shift to other types of hazards and affectedobjects (Carpenter, 1996) Ecological risk assessment (EcoRA) has already evolvedinto separate methodology under the general RA framework

When applied to a particular site and/or project, RA procedures include severalgeneric steps such ashazard identification, hazard assessment, risk estimation and risk evaluation.

8 CHAPTER 1

Often contrasted in conceptual terms, EIA and RA have a common ultimate goal —

“the rational reform of policy-making” (Andrews 1990) Both assessment tools areintended to provide reasoned predictions of possible consequences of planned deci-sions to facilitate wiser choices among the alternatives To link risk assessment andimpact assessment paradigms one can suggest a definition ofenvironmental impact as

any change in the level of risk undergone by receptors of concern that are reasonablyattributable to a proposed project (Demidova, 2002)

The following reasons for integrating EIA and RA are frequently distinguished

On one hand, it has been presumed that EIA can benefit from utilizing RA approaches,

in particular in order to improve the treatment of human health issues and uncertainimpacts It has been argued that RA could make impact prediction and evaluationmore rigorous and scientifically defendable Beyond impact analysis, RA can facil-itate analysis of alternatives and impact mitigation strategies Apart from obviousbenefit for impact assessors this would provide for “greater clarity and transparency

in decision making” (Eduljee, 1999) and help manage risks at the project tation stage On the other hand, the integration might help to institutionalize the RAprocedure in the framework of such a widely used decision-support tool as EIA Itmay also enhance RA with public participation and consultation elements borrowedfrom EIA

implemen-Few jurisdictions have mandatory legal provisions for RA application within EIA(e.g., Canada, USA (Smrchek and Zeeman, 1998; Byrd and Cothern, 2000)) There is

no universally agreed methodological and procedural framework to integrate RA intoEIA and only a limited number of practical recommendations for improvements in theEIA process that would facilitate such integration Nevertheless, many researcherslinked comprehensive impact assessment with using “scientifically based” risk as-sessment methods (see, e.g., Andrews, 1990; Arquiaga et al., 1992; Canter, 1996;Lackey, 1997)

Moreover, a number of approaches for EIA–RA integration have already been posed (see, e.g., Arquiaga et al., 1992; NATO/CCMS, 1997; Eduljee, 1999; Poborski,1999) Most of them follow the widely accepted idea of “embedding” risk assess-ment into EIA and incorporating RA methods and techniques into EIA methodology;they are organized according to the sequence of generic EIA stages discussed above(see Demidova (2002) for in-depth discussion) A general model for integrating RAinto EIA, which summarizes many of them, is presented in Demidova and Cherp(2004)

pro-4 ASSESSMENT OF ECOSYSTEM EFFECTS IN EIA: METHODOLOGICAL

PROMISES AND CHALLENGESAny changes in the environment resulting from the proposed projects including im-pacts on ecosystems are under the EIA scope At the same time, the traditional focus

of EIA is the quality of environmental media: ambient and indoor air, water, soilparameters of human biophysical environment According to reviews of EIA prac-tice, potential impacts of proposed developments on biota and natural ecosystems has