November 13, 2009 by Mark Crane
A book on Environmental Quality Standards, edited by Graham, Dawn and me has just been published by CRC Press.
What are Environmental Quality Standards?
Chemical standards are widely used to protect the environment and human health from substances released by human activity. Generally speaking, standards relate to doses or concentrations in the environment for specific chemicals, below which unacceptable effects are not expected to occur. Many standards are legally enforceable numerical limits, such as Environmental Quality Standards for List 1 chemicals in water, or Annex X and VIII standards under the European Water Framework Directive. Others are not mandatory, but are contained in guidelines, codes of practice, or sets of criteria for deciding individual cases. Some standards are not set by governments, but carry authority for other reasons, especially the scientific eminence or market power of those who set them (e.g. World Health Organisation guidelines).
The ways in which Environmental Quality and Human Health Standards are derived, and the frameworks within which they are used, differ between countries and regions, with standards being derived, expressed, monitored and implemented in different ways. To some extent this diversity reflects genuine technical differences that must be taken into account in the development of standards for different compartments (e.g. water or soil) or for different receptors (e.g. humans, livestock, or flora and fauna). However, much standard-setting has been developed in a piecemeal fashion with little consistency between schemes in the levels of protection sought, the selection of chemicals for which standards may be needed, the methods used to derive them, or the methods used to monitor compliance. These differences can lead to the implementation of substantially different values from the same empirical data, which must mean that their application is either over- or under-precautionary in at least some situations.
The SETAC Technical Workshop on the Derivation and Use of Environmental Quality and Human Health Standards for Chemical Substances in Water and Soil was held in Faringdon, Oxfordshire, UK from October 16th to 19th 2006. The workshop addressed the methods by which substances are selected and prioritised for standards derivation, the way in which these standards are derived (e.g. EU Technical Guidance Document and Water Framework Directive approaches, EU Member State, North American and other international approaches) and the way in which they are implemented (e.g., mandatory pass/fail, probabilistic (e.g., 95th percentiles), or tiered risk assessment frameworks). Soil and water standards were considered, as were values for the protection of human health and the natural environment. The focus was on European regulatory frameworks, although expert input was sought from other jurisdictions internationally. Chemical standards for aquatic (water and sediment) and terrestrial (soil and groundwater) systems were the main focus for the meeting. This workshop built on, and included some participants from, a 1998 SETAC workshop on Re-evaluation of the State of the Science for Water-Quality Criteria Development (Reiley et al. 2003).
Workshop Objectives and Topics
The workshop brought together 35 scientists and professionals from 11 countries, with expertise across risk assessment, environmental and health sciences, and social science and economics disciplines, including toxicologists, chemists, risk assessors, economists, sociologists and managers, as well as regulators and policy makers. These individuals were selected to provide sectoral (academic, government and private sector), geographical and gender balance to the workshop.
The proposed objectives and topics of the workshop were:
Scientific and risk assessment of aquatic (water and sediments) and terrestrial (soil and groundwater) data for derivation of standards
- How should substances be selected and prioritised for standard setting?
- Which biological assessment endpoints should be used for setting standards (e.g., community, population, individual, cellular, biomarker, omics, etc.)?
- How should data be assessed for reliability and relevance?
- How should background or ambient concentrations of substances be considered when deriving or using standards?
How can standards be validated or verified and what should be the role of field (e.g., epidemiological) and semi-field (e.g., microcosm or mesocosm) data?
- What environmental and human health risks from substances should we protect against and at what level of protection?
- How should uncertainty be taken into account when setting standards?
- What is the appropriate choice of assessment factors and statistical extrapolation models in relation to data quantity and quality?
- How should regional, national and site-specific risks be accounted for?
- What are the differences in the scientific and risk assessment approaches used to derive environmental versus human health standards, and can these differences be justified?
- What are the differences in the scientific and risk assessment approaches used to derive aquatic versus terrestrial standards, and can these differences be justified?
Implementation analysis and assessment of technological options
- At what point should implementation analysis be performed and what should be the analysis inputs and outputs?
- What techniques should be used for implementation analysis?
- What are the most effective implementation strategies?
- How should compliance monitoring statistics and practice be defined for Standards?
- At what point should technological options be assessed when deriving a standard and what should be the assessment inputs and outputs?
- What assessment techniques should be used to assess technological options?
- Can standards be used to drive technological innovation?
- What are the differences in the implementation analysis and assessment of technological options for environmental versus human health standards, and can these differences be justified?
- What are the differences in the implementation analysis and assessment of technological options for aquatic versus terrestrial standards, and can these differences be justified?
Social and economic appraisal of standards
- At what point should the costs and benefits of particular standards be appraised and what should be the appraisal inputs and outputs?
- When is a cost-effectiveness analysis sufficient?
- What techniques should be used in cost-effectiveness and cost-benefit analyses?
- At what point should the public and direct stakeholders be involved in the derivation and use of standards?
- What are the advantages and disadvantages of public and stakeholder involvement?
- What are the best involvement techniques and strategies?
- What is the appropriate use of ‘expert judgement’ when deriving or using standards?
- What are the differences in the socioeconomic analysis of environmental versus human health standards, and can these differences be justified?
- What are the differences in the socioeconomic analysis of aquatic versus terrestrial standards, and can these differences be justified?
Workshop participants were assigned to one of four breakout groups:
- Scientific and risk assessment approaches for derivation of environmental and human health standards for the aquatic environment (water and sediment).
- Scientific and risk assessment approaches for derivation of environmental and human health standards for the terrestrial environment (soil and groundwater).
- Technological appraisal and implementation of environmental and human health standards for aquatic and terrestrial environments.
- Socioeconomic analysis of environmental and human health standards for aquatic and terrestrial environments.
The results of the workshop are contained in this monograph. Chapter 2 outlines the social and economic frameworks within which Standards are derived and used, and provides a wider context for considering when, where and how standards should be implemented. Chapter 3 continues this theme and explores general issues associated with implementing any standard. Chapters 4 and 5 consider the detail of deriving and implementing aquatic and terrestrial standards. Finally, in Chapter 6, we draw together the overall conclusions of the workshop and provide recommendations on the development and use of standards. We also identify future research that would help to underpin the science of environmental and human health standards.