Like any other policy, environmental policies should be carefully assessed, both prior to their implementation and after they have been in place for some time. In-depth evaluations require that a value be placed on the benefits that environmental policies provide, so that they can be compared to the costs of the policy, using a common metric.
OECD has done, and is continuing to do, much work to help policy makers in this regard. The book Cost-Benefit Analyses and the Environment: Recent Developments discussed recent developments in the area of policy assessments and reviewed conceptual and methodological developments in this regard.
With respect to so-called Extended Producer Responsibility schemes in particular, the document "Policy Interventions to Address Health Impacts Associated with Air Pollution, Unsafe Water Supply and Sanitation, and Hazardous Chemicals" provides additional details on how to carry out a cost benefit analysis. Most of the document has more general validity.
A major part of the benefits of many environmental policies (e.g. regarding local air pollution and water pollution) is the reductions in human mortality that they will entail. It is, hence, important to place a value on the lives that these policies save – a Value of a Statistical Life (VSL), or the value of a delayed fatality. To help countries get a stronger basis for doing so, OECD has done a meta-analysis of all available VSL estimates based on surveys where people have been asked what they would be willing to pay to reduce mortality risks in an environmental, health or traffic context. Based on these analyses, the book Mortality Risk Valuation in Environment, Health and Transport Policies gives practical guidance on how to incorporate VSL estimates in policy assessments.
The document "A Review of Recent Policy-Relevant Findings from the Environmental Health Literature" estimates where people have been asked how much they would be willing to pay to reduce non-mortal environment-related health risks and assessed the recent empirical literature in the publication "Policy Interventions to Address Health Impacts Associated with Air Pollution, Unsafe Water Supply and Sanitation, and Hazardous Chemicals" regarding quantification and valuation of the human health impacts of air pollution, hazardous chemicals, and unsafe water and sanitation, and their use in cost-benefit analysis.
Valuation of environment-related health impacts for children poses a number of particular problems that OECD’s VERHI project sought to address. This involved the implementation of surveys in three OECD countries (United Kingdom, Italy, Czech Republic) by leading experts in the field of health valuation. Results indicate that people value risk reductions for children greater than those for adults, but there is variation across country, methodology and context.