Investigators: Alexander Larcombe, Emily Chivers
External collaborators: Dr Caitlin Wyrwoll (University of Western Australia), Associate Professor Nathan Pavlos (University of Western Australia), Professor Sotiris Vardoulakis (Australian National University), Associate Professor Melinda Coughlan (Monash University)
Plain language summary: Levels of carbon dioxide in the air are currently higher than they have ever been and they are expected to more than double in the next 100 years. The health effects of long-term exposure to such levels of carbon dioxide are unknown, although short term exposure is known to impair cognitive function and adversely impact the lungs, kidneys and bones. Using mouse models, this study will provide the first detailed information of potential risks of higher ambient carbon dioxide concentrations.
Project description:
Greenhouse gas emissions due to anthropogenic activities are driving global climate change. Levels of carbon dioxide (CO2) in our atmosphere are now higher than humans have ever previously experienced. Climate change models for the future include scenarios where atmospheric CO2 in 2100 may triple to over 1000 parts per million (ppm) compared with 310 ppm in 1950. Despite this, media attention, public concern and policy initiatives have focused particularly on global warming.
There has been little consideration of possible direct toxic effects on health of increasing ambient CO2 levels – particularly when these will be sustained across whole lifetimes. While short-term high dose exposure to CO2 can be lethal, lower-dose, chronic exposure leads to impaired cognitive function and a range of other potential adverse effects on the lungs, kidneys and bones. To-date, “chronic” exposure has been of the order of a few weeks to months, such as that experienced by submariners or astronauts. In these situations, “escape” to ambient air with a low CO2 level is possible, with reversal of adverse effects. It is not logistically possible to study the effects of lifetime exposure to the levels of CO2 that are projected for the nearfuture in humans.
Our team has the skills, experience and equipment to test physiological and behavioural outcomes of exposure to realistic levels of ambient CO2 from in utero to old age. This study will provide the first detailed information of potential risks of higher ambient CO2 concentrations per se, rather than the health risks due to the effects of increasing energy in the climate system. In 2018 we completed a series of preliminary studies which showed that lifetime exposure to 900ppm CO2 results in a range of behavioural and physiological impairments.