EUROPEAN COMMISSION DIRECTORATE-GENERAL HEALTH AND CONSUMER PROTECTION Directorate C – Scientific Opinions on Health Matters Unit C2 – Management of Scientific Committees I Scientific Committee on Toxicity, Ecotoxicity and the Environment Brussels, C2/JCD/csteeop/Ter91100/D(0) SCIENTIFIC COMMITTEE ON TOXICITY, ECOTOXICITY AND THE ENVIRONMENT (CSTEE) Opinion on THE AVAILABLE SCIENTIFIC APPROACHES TO ASSESS THE POTENTIAL EFFECTS AND RISK OF CHEMICALS ON TERRESTRIAL ECOSYSTEMS Opinion expressed at the 19th CSTEE plenary meeting Brussels, 9 November 2000 CSTEE OPINION ON THE AVAILABLE SCIENTIFIC APPROACHES TO ASSESS THE POTENTIAL EFFECTS AND RISK OF CHEMICALS ON TERRESTRIAL ECOSYSTEMS FOREWORD AND SCOPE OF THIS DOCUMENT The concept "terrestrial environment" cannot be easily defined. It is characterised as the part of the biosphere that is not covered by water, less than one third of the total surface. From a geological viewpoint it just represents a thin line (a few meters wide) of the interface between both the solid (soil) and the gaseous (atmosphere) phases of the Earth, several orders of magnitude wider than this line. However, from the biological point of view, this thin line concentrates all non-aquatic living organisms, including human beings. Humans use the terrestrial environment for living and developing most of their activities, which include the commercial production of other species by agriculture and farming. Human activities deeply modify the terrestrial environment. Particularly in developed areas such as Europe, the landscape has been intensively modified by agricultural, mining, industrial and urban activities and only in a small proportion (mostly in extreme conditions such as high mountains, Northern latitudes, wetlands or semi-desert areas) of the European surface the landscape still resembles naive conditions. Wildlife has been forced to adapt to the new conditions or to disappear. Nature shows examples of adaptation and species extinction. Nevertheless, from the Polar Regions of Scandinavia to the arid zones of the Mediterranean countries terrestrial ecosystems more or less adapted to human activities, in particular agriculture, can be found. Chemical pollution represents an additional threat for living organisms. In the particular case of the terrestrial environment it can potentially affect human populations, human economy by acting on crop and livestock production and quality, and wildlife. Ecotoxicologists normally consider as the ultimate end-point the assessment of effects on the structure and function of the ecosystem. This also implies that this level of protection will also guarantee the anthropogenic uses of the environment. The protection of soil functions also protects the capability of the soil to be used for agricultural purposes; protection of populations include domestic as well as wild species. The protection goal in both cases is at the population or community level Hence, it is not necessary to protect each single rabbit or each single plant of wheat, but the rabbit population and the wheat yield. Domestic species represent an infinitesimal percentage of the total number of species, and it is expected that in most cases, the levels of chemicals in the environment required to protect ecosystems should be lower than those required for the protection of these human activities. In other words, a proper ecological risk assessment is sufficient for the evaluation of adverse effects on real ecosystems and associated agro-systems. Other concerns, indirectly related to the loss of living organisms (soil erosion associated to the loss of vegetation cover, climate change associated to deforestation) are also covered by the ecosystem evaluation; obviously, any significant change to the vegetation cover, including trees will provoke dramatic changes on the structure and function of the ecosystem. If human beings are explicitly included in the evaluation, there are both similarities and differences. Humans are part of the terrestrial environment and as such will be exposed to chemical pollutants in similar ways to other vertebrates. Environmental exposures to contaminated soil, air and food can be evaluated at least in parallel ways for humans and for wild vertebrates. However, the required level of protection is different. As for environmental concerns, the population as a whole must be protected (e.g., in terms of growth rate). However for human populations, a higher level of protection is also needed where it is necessary to protect each individual human being. Therefore risk assessments are often divided into Human Health risk assessment (which include the exposure of humans through the environment as well as direct exposure during the life cycle of the chemical) and Ecological risk assessment (which by protecting ecosystems is also expected to protect the "use" of the environmental resources by humans) The CSTEE is in favour of the on-going approaches regarding the integration of both Human Health and Ecosystem risk assessment. However, it is necessary to have an adequate understanding of each part before any integration. Therefore, this CSTEE opinion focuses exclusively on the hazard and risk assessment of the effects of chemicals on terrestrial ecosystems, recognising that a holistic assessment of the terrestrial environment requires additional considerations and in particular, the integration of human beings and their activities as part of the terrestrial compartment. Table of contents TABLE OF CONTENTS 1. INTRODUCTION. 1.1. REGULATORY USE OF HAZARD IDENTIFICATION AND RISK ASSESSMENT 1.2. MANDATE 1.3. HAZARD AND RISK ASSESSMENT FOR THE TERRESTRIAL COMPARTMENT IN THE EU REGULATION 2. PRINCIPLES FOR ECOLOGICAL RISK ASSESSMENT AND THEIR APPLICABILITY TO TERRESTRIAL ECOSYSTEMS. 2.1. PROBLEM DEFINITION AND SELECTION OF SCENARIOS 2.2. IDENTIFICATION AND QUANTIFICATION OF RELEVANT EXPOSURE ROUTES 2.3. EFFECT ASSESSMENT: HAZARD IDENTIFICATION AND DOSE- RESPONSE ASSESSMENT 2.4. RISK CHARACTERISATION AND RISK REFINEMENT 2.5. DEFINITIONS AND ABREVIATIONS 3. HAZARD IDENTIFICATION. 3.1. INTRODUCTION 3.2. ESTABLISHING ENVIRONMENTAL CONCERNS 3.3. SELECTION OF ASSESSMENT ENDPOINTS: 3.4. SELECTION OF MEASURABLE ECOLOGICALLY RELEVANT PROPERTIES 3.5. ALTERNATIVES TO INCORPORATE SCIENTIFICALLY SOUND CRITERIA WHEN SETTING HAZARD CATEGORIES 4. TOOLS FOR EFFECT ASSESSMENT. 4.1. INTRODUCTION 4.2. LABORATORY "SINGLE-SPECIES" ECOTOXICOLOGICAL EFFECT TESTS 4.3. EXPERIMENTAL APPROACHES: MULTISPECIES TESTS 4.4. MEASUREMENT OF SOIL PROCESSES 4.5. CONCLUSIONS AND OUTLOOK Table of contents 5. DOSE /RESPONSE RELATIONSHIPS AND METHODS FOR SETTING ECOTOXICOLOGICAL THRESHOLDS AND QUALITY OBJECTIVES. 5.1. INTRODUCTION 5.2. DATA QUALITY AND (UN)CERTAINTY OF INPUT 5.3. EXTRAPOLATION METHODS 5.4. VALIDATION OF MATHEMATICALLY DERIVED QUALITY DATA USING MULTISPECIES AND FIELD DATA 5.5. QUALITY OBJECTIVES FOR MIXTURES 6. EXPOSURE ASSESSMENT. 6.1. EXPOSURE THROUGH SOIL 6.2. EXPOSURE THROUGH AIR 6.3. EXPOSURE THROUGH FOOD INCLUDING DRINKING WATER 6.4. METHODS FOR ASSESSING PEC IN THE TERRESTRIAL ENVIRONMENT 6.5. COMPARISON/USE OF EXPOSURE PREDICTION AND DATA OBTAINED IN MONITORING PROGRAMMES 7. RISK CHARACTERISATION. 7.1. VALUE AND LIMITATIONS OF TERS AS A TOOL FOR RISK CHARACTERISATION 7.2. RISK CHARACTERISATION AT HIGHER HIERARCHICAL LEVELS 7.3. BIOMAGNIFICATION RISK FOR PERSISTENT AND BIOACCUMULABLE CHEMICALS 7.4. RISK ASSESSMENT FOR AREAS OF HIGH ECOLOGICAL VALUE 8. RECENT PROPOSALS ON HAZARD AND RISK ASSESSMENT FOR THE TERRESTRIAL ENVIRONMENT. 8.1. OECD PROPOSALS 8.2. USEPA GUIDELINES FOR ECOLOGICAL RISK ASSESSMENT 8.3. PROPOSALS FROM THE SETAC WORKSHOPS 8.4. PREVIOUS OPINIONS OF THE CSTEE REGARDING THE HAZARD AND RISK ASSESSMENT FOR THE TERRESTRIAL ENVIRONMENT. 9. THE CURRENT STATE OF THE ART AND ITS POSSIBILITIES FOR DECISION MAKING. 9.1. HAZARD COMPARISON AND CLASSIFICATION. SCIENTIFIC BASIS FOR THE IDENTIFICATION OF DANGEROUS SUBSTANCES 9.2. INFORMATION SUPPORTING THE DERIVATION OF QUALITY STANDARS 9.3. INFORMATION SUPPORTING RISK ASSESSMENT 10. CONCLUSIONS AND RECOMMENDATIONS. Chapter 1. Introduction CHAPTER 1 INTRODUCTION 1.1 REGULATORY USE OF HAZARD IDENTIFICATION AND RISK ASSESSMENT Hazard and risk assessment are key elements in the regulation of chemical substances. Their role within the European Union system has been recently reviewed by Hard et al., (1998). In principle, four main regulatory uses can be identified: • Identification and comparison of dangerous chemicals • Setting quality standards • Development of environmental indicators • Decision-making at the local (contaminated sites) and generic (activities, life- cycle assessment of substances, regulation of chemicals including registration/authorisation, etc.) levels. The current status of each aspect will be discussed below. Hazard assessment constitutes the essential tool for the evaluation of the potential effects of chemicals on organisms and ecosystems. It includes a first step, hazard identification, which must detect the potential dangers of the substance (i.e. the kind of effects that the substance may produce), and a second step to quantify each danger and to set the expected dose/response relationships. At the regulatory level, hazard identification/quantification can be used as independent tools or, alternatively, as part of the risk assessment. Risk Assessment aims to estimate the probability for adverse effects to occur, in doing this assessment the risk manager applies specific protocols to compare the potential hazard with the expected level