Negative health impacts of climate change – Dr Darshini Heaney

Negative health impacts of climate change – Dr Darshini Heaney

While talking to parliamentarians with Citizen’s Climate Lobby in March 2017,  were told that the negative health consequences of climate change is an area where there is bipartisan interest and concern. The following is a summary of the points made in a discussion CCL volunteer Dr Darshini Heaney  led during a recent CCL Australia Zoom Monthly Meeting.

There are numerous ways health is affected by climate change.

1.  Heatwaves

These are increasing in intensity, frequency and duration.  There has been a doubling of record hot days since 1960.

They have caused more deaths since 1890 than cyclones, bush fires, earthquakes, floods and severe storms combined.

There has been a steady increase in mortality in summer compared to winter over the last four decades, suggesting that climate change is already altering health outcomes.

In the January 2009 Victorian heatwave, there was a 46% increase in emergency call outs on the three hottest days.  Cardiac attacks tripled.  There were 374 excess deaths in the heatwave, a 62% increase compared to the previous year, whereas the fires themselves caused 173 deaths.

Heat waves cause heat stroke and heat exhaustion as well as worsening in heart, lung and kidney disease.  They possibly cause an increase in preterm birth and underweight babies.  The most vulnerable populations include the elderly, young children, pregnant women and those in financially disadvantaged communities.

Heatwaves are associated with power failures – lack of air conditioning then exacerbates the risk of adverse health outcomes.  The loss of refrigeration can cause wastage of medicines and vaccines, many of which require refrigeration.  Also there is an increased risk of gastrointestinal diseases due to food spoilage.

2.  Bush fires

The risk of bush fires has increased and is expected to continue to increase, especially in south eastern Australia.

They cause death and illness directly through burns, injuries, dehydration, heat exhaustion and smoke inhalation – this of course includes fire fighters.

The more indirect effects include damage to hospitals and medical centres.

The mental health effects are yet another cost – these can be devastating and long standing.  Following the 2003 Canberra bush fires, the was a significant increase in emotional and behavioural problems in children involved.  About 50% displayed some post traumatic stress symptoms.

3.  Floods and Storm Surges

There is the direct effect of drowning and injuries.

Contaminated water caused directly by floods or by damage to sewage treatment infrastructure pose a significant risk of gastrointestinal infectious diseases.

There is an increase in mosquito borne disease due to an increase in breeding grounds for the mosquitoes.

Again there is a significant effect on mental health.  The 2011 Queensland floods affected more than 78% of Queensland.  People affected were twice as likely to display mental health symptoms, including  those suggesting PTSD, than individuals who were not affected.

4.  Infectious Diseases

The changes in temperature and rainfall mean an increased risk of mosquito borne disease, such and Ross River Fever and Dengue Fever, much further south than was seen in the past.

5.  Allergies

Increasing levels and carbon dioxide and higher temperatures result in an increase in production, potency and release of pollen and fungal spores.  Damp conditions following storm surges and floods promote the growth of mould.  These are all triggers for asthma and other allergic conditions.

Air pollutants such as nitrogen oxides, ground level ozone, particulate matter and sulphur dioxide can aggravate asthma and contribute to the development of asthma in children.

6.  Air Pollution

Across Australia, air pollution contributes to about 3000 deaths per year (compared to a road toll of 1209 in 2015).  It is estimated that it causes 6.5 million deaths a year worldwide.

Burning coal to generate electricity releases many pollutants,including particulate matter, sulphur dioxide, nitrogen oxides, mercury, cadmium and arsenic.  these pollutants contribute to lung cancer, other lung disease such as asthma, heart disease and stroke.

Urban smog contains a number of pollutants.  One of them is ground level ozone, the levels of which increase on hot, sunny days.  Ozone is a potent airway irritant, triggering asthma.  Just in Sydney, by 2050, the number of hospital admissions caused by ozone pollution is expected to double.

In conclusion,  as shown in this summary, the effects of climate change on health is myriad and deeply concerning.  As a general practioner, it is my role to try to tackle the root causes of illness.  My efforts with Citizen’s Climate Lobby allow me to attempt to achieve this, with respect to climate change, in the most effective way I can.

Darshini Heaney

Member of Citizen’s Climate Lobby
Member of Doctors for the Environment

Further Reading:
Climate and Health in Australia Factsheets, from Doctors for the Environment (DEA), Australia
DEA Climate and Health in Australia Factsheet – downloadable and very well referenced