30 March 2011

Health and the Environment: A compilation of evidence

The Australian Institute of Health and Welfare has released a useful summary of the links between health and the environment:

Why look at environment and health?

There is increasing awareness that our health and the environment in which we live are closely linked, and in 2006 the World Health Organization (WHO) estimated that 24% of the global burden of disease was due to modifiable environmental factors. This growing awareness is reflected in recent health and environmental initiatives from governments and other organisations.

How does this report help?

Given the abundance and diversity of literature, it is useful to summarise and increase access to information regarding health and the environment. As new evidence is constantly emerging, this report does not seek to provide definitive conclusions about this relationship. Rather, it draws upon key studies and synthesises the main findings related to a selected list of 15 environmental factors. The report also notes that it can be difficult to assess the relationship between health status and environmental factors for a number of reasons.

What are the main findings?

Overall, the report indicates that the environment can be a major determinant of our health and how we live. In general, the results reported here demonstrate that:

  • Our surroundings can influence our health through a variety of channels—through exposure to physical, chemical and biological risk factors or by triggering changes to our own behaviour or the behaviour of those around us. Such effects may be direct (such as injury or death) or indirect (through changes in lifestyle and health behaviours).
  • The environment has the potential to affect physical health (for example, respiratory problems due to air pollution) and mental wellbeing (for example, poor mental health associated with drought conditions). Conversely, there are natural and modified features of the environment (such as green space and water fluoridation) which benefit health.
  • There is a growing awareness that humans, through their intervention in the environment, play a vital role in exacerbating or reducing health risks.

Examples of the report’s detailed findings include:

  • From official records, bushfires killed 815 people in Australia between January 1851 and December 2010 (see Section 3.3).
  • A large study found that people living in more walkable neighbourhoods (characterised by connected streets, high residential density and pedestrian-oriented shopping) were less likely to be obese than people living in less walkable areas (see Section 4.3).
  • A study using data from the National Health Survey showed that overcrowding was responsible for 30% of the health gap between Indigenous adults living in remote areas and the non-Indigenous population (see Section 4.7).

What don’t we know?

There is a lack of data on exposure to environmental hazards and health outcomes, particularly at a local level. As such, the health effects of many aspects of the environment have not been systematically evaluated, and there is associated uncertainty about causality because the pathways involved may be indirect and complex. Despite these limitations, this report provides insight into the relationship between the environment and health

The data is quite focused on the Australian context but it's still well worth a look. You can download the report here.