Health Impact Assessments

A Tool to Assess and Mitigate the Effects of Policy Decisions on Public Health

October 2008

By Doug Farquhar

Adobe PDF PDF Version Complete 7-page document. To view PDF files, you must install Adobe Acrobat Reader.

How does a policymaker determine the effect a particular policy could have on the public’s health? Legislation that addresses health and health care, transportation planning, land use, air and water pollution, economic policy can affect public health. With any major government-funded project, the environmental effects are well documented through environmental assessments (EA) and environmental impact statements (EIS).

Legislators in California, Connecticut, Maryland, Massachusetts, Minnesota, Missouri, Tennessee, Washington and Wyoming have begun to consider the issue. The public health implications of decisions made by policymakers, public health officials, community planners, transportation directors and other officials often are substantial. Legislators in these states are beginning to link the health effects to funding appropriated or decisions made by state officials. This objective analysis—a health impact assessment—can provide information about the effects of a project on public health.

Health impact assessments (HIA) are “…a combination of procedures, methods, and tools by which a policy, program, or project may be judged as to its potential effects on the health of a population, and the distribution of those effects within the population.”1 These assessments can objectively evaluate the potential health effects of a project or policy before it is built or implemented. They can provide recommendations that increase positive health results and minimize adverse ones. Perhaps most important, the assessments include health as an interest for consideration in public policy.

Although it resembles an environmental impact statement, a health impact assessment has a different goal. Its purpose is to present policymakers with a set of evidence-based recommendations about the potential health effects of a proposal or project. A health impact assessment offers a systematic, comprehensive approach to assess health issues associated with a program or project. It follows environmental impact statement procedures and methods to assess potential health effects and develop recommendations to protect and promote health.

An environmental assessment or, if warranted, an environmental impact statement, provides policymakers and the public with evidence of the environmental affects of a government action, based on a procedural review and scientific analysis of the project. Under federal law,2 this procedure is mandatory for any project that involves federal funding; 15 states3 and three territories have adopted similar policies. Although federal law (and, by following this law, the states) emphasizes the need to assess the effects of a project or policy on the public’s health, health assessments have been, until recently, secondary to environmental effects. At least in this country, neither the environmental assessment nor the environmental impact statement usually addresses health.4

A pure health impact assessment focuses on human health and overall or specific factors that affect it, including physical, economic, social and cultural aspects. The assessment can review the extent of a policy’s effect on a community, ensuring that vulnerable populations are not adversely affected. It can provide policymakers with an unbiased assessment based on the evidence, looks for possible problems, and offers a set of recommendations that promote health benefits and minimize health risks. It can gauge health benefits, to evaluate whether specific actions result in improved health. An assessment can determine, before initiation of a transportation project, for example, if the project will adversely affect public health. The intent of a health impact assessment is not to make decisions, however; rather, it is designed to provide decision makers with clear, transparent information about public health.

U.S. policymakers have routinely performed health assessments to guide decisions, either voluntarily or under the auspices of an environmental impact statement. One example of such an assessment is efforts by transportation planners to determine the number of vehicle crashes or pedestrian injuries. Another example is to collect data on the potential for respiratory illness or lung disease in a local community when siting a coal-fired power plant or other facility. Estimates on the extent of environmental impacts, such as excess discharges into water or air pollution, also offer insights into the potential effect on health.

A health impact assessment usually consists of six major steps.

Screening to identify projects or policies for which a health impact assessment would be useful.
Scoping to determine:
- the proposals at stake;
- the likely health effects, and which need further assessment; and
- those involved with the policymaking (legislators, agency officials, researchers).
Assessing risks and benefits to identify who may be affected and how they may be affected.
Developing recommendations by suggesting changes to a proposal to promote positive or mitigate adverse health effects.
Reporting the results to decision makers).
Evaluating and monitoring to determine the effect of the health impact assessment on the decision process.5

How does a policymaker determine the effect a particular policy could have on the public's health? Legislation that addresses health and health care, transportation planning, land use, air and water pollution, economic policy can affect public health. With any major government-funded project, the environmental effects are well documented through environmental assessments (EA) and environmental impact statements (EIS).

Back arrow, return to previous page Environmental Health