SEGH Articles

Health in Impact Assessment: primer published

02 July 2017
The changes to the EIA directive as recast in April this year (2017) brings human health very firmly into consideration. Any project which is subject to EIA (Environmental Impact assessment) is required to evaluate the impact from the project on human and population health.

The changes to the EIA directive (  as recast in April this year (2017) brings  human health very firmly into consideration. Any project which is subject to EIA (Environmental Impact assessment) is required to evaluate the impact  from the project on human and population health.  Projects may range from major infrastructure projects, such as new railways and airport runways, waste incinerators, industrial scale agricultural activities, to applications for fracking, open cast mines, amongst others.


In order to move the consideration of human and population health central stage within the process of impact assessment, the Institute of Environmental Management and Assessment (IEMA) has worked with Ben Cave Associates, and the Faculty of Public Health, to produce a primer which is intended to spark discussion across all professionals. Impact assessment requires the input of many different specialists; it is hoped that all of them will become engaged in this debate.

Although Health Impact Assessment  (HIA) has been carried out successfully for many projects, evaluation of human and population health has sadly been missing from many projects. It is worth remembering that the impacts can be both positive and negative. Getting the balance right is imperative. Impacts may derive from release of contaminants during the construction phase, through to contamination of water, release of proposed use of chemicals of concern, or equally may be the health benefits of the construction of a new health care facility, with release of dust and noise during the construction phase, but with a longer term overall benefit. Likewise, the disruption and impact from construction of a railway may be negative, but a shift in mode of transport away from the car in developed nations brings about improved air quality, and in developing nations provides transport which may previously have been absent, improving quality of life, not least of which may be access to healthcare facilities, or the ability to transport perishable goods to market in a timely manner. It should not be assumed that a HIA will try to get in the way of development, but rather that it will look at appropriate outcomes.


Balancing the various impacts is context sensitive. The geology and geography of the land to be developed will vary.  For example, water availability, permeability of rocks, or fragility of habitats, will vary, depending upon the location of a project, as will a wide number of other considerations. Identifying these issues correctly and evaluating health impacts is imperative.

The directive also requires adherence to the principle of resource efficiency. A move away from mining for new materials for production, to a requirement for re-use of materials, helps to decrease the impact on many communities, as well as the land itself. The directive requires a move towards sustainability.

Health Impact Assessment takes into account not only the ‘hard’ environmental impacts, but also the less visible ones, such as social cohesion, engagement with hard to reach communities, loss of amenity as well as impact on employment.

The EIA directive does not explicitly ask for a full  HIA to be carried out. However, in order for meaningful evaluation of human and population health to be taken into account, engagement needs to be early, and cross sectoral, as well as competent. HIA can do this. The primer does not argue for full HIAs to be undertaken, simply that human and population health is evaluated in a timely and competent manner.

As an organisation which promotes consideration of health from many directions, the research which SEGH members undertake can often be influential in the decision –making which Impact Assessment needs to undertake. Personally, I have often quoted pieces of research which have been presented at SEGH conferences. Although HIA professionals work with a good evidence base, sometimes it is necessary to err on the side of caution. Extending our evidence base is imperative. One of the stated aims of SEGH is the sharing of knowledge. Using that knowledge wisely for the good of others is the outcome we should seek.

Although the  IEMA primer is intended to be used initially in the UK, the questions which we pose are legitimate in other countries too. (Like SEGH, IEMA is an international organisation.)  Early intervention and engagement can ensure best outcomes for all concerned, driving best practice, and improving the health outcomes of   wider communities.

 The pdf is free to download from IEMA.  ( Hard copies are available from IEMA, but the cost of these is £25.00.

Please feel free to use this within your various communities.

By Gillian Gibson, Gibson Consulting and Training

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