Climate change, and our attempts to prevent it, can worsen indoor air quality and make people sick.
That's are the key finding of a report compiled by the Institute of Medicine of the National Academies at the request of the U.S. Environmental Protection Agency.
There isn't enough evidence to say whether climate change was already harming indoor air quality, the report finds. 'However, available research indicates that climate change may make existing indoor environmental problems (worse) and introduce new problems,' the report says.
It reviewed existing science, and found it lacking.
'(T)here is a clear lack of recognition of this topic at a level commensurate with its importance,' the report says, noting that the issue does not 'fall neatly under the aegis of any federal department or agency.'
Perhaps the most attention-grabbing notion is that 'green' buildings can endanger public health. That's because they seek to save energy use by, among other things, adding insulation and sealing leaks.
'Research indicates that poor ventilation in homes, offices and schools is associated with occupant health problems and lower productivity,' the report says.
'Climate change may make ventilation problems more common or more severe in the future by stimulating the implementation of energy-efficiency (weatherization) measures that limit the exchange of indoor air with outdoor air.'
This finding is particularly noteworthy now, because many developers are erecting buildings that meet various green standards that include weatherization and sealing of the building envelope. And many governments have started requiring new public and, in some cases, private buildings to achieve green certifications, such as those under the U.S. Green Building Council's Leadership in Energy and Environmental Design program.
'The United States is in the midst of a large experiment of its own making in which weatherization efforts, energy-efficiency retrofits, and other initiatives that affect that characteristics of interaction between indoor and outdoor environments are taking place and new building materials and consumer products are being introduced indoors with little consideration of how they might affect the health of occupants,' the report says.
'Experience provides a strong basis to expect that some of the affects will be adverse, a few profoundly so.'
It should be noted that many green-building standards include minimizing use of materials that contribute to indoor air pollution by giving off fumes and gases. And many green buildings prioritize bringing in outside air during warmer periods by having windows that open, a rarity in office buildings.
The report also finds that climate change itself can worsen indoor air quality.
'Increased use of air conditioning, an expected adaptation measure, could exacerbate emissions of greenhouse gasses and, if accompanied by reduced ventilation rates, increase the concentration of pollutants emitted from indoor sources,' it says.
'The potential for poisoning from exposure to carbon monoxide emitted from portable electricity generators may increase if peak electricity demand due to heat waves or extreme weather events leads to power outages.'
Then there's moisture.
''Extreme weather conditions associated with climate change may lead to breakdowns in building envelopes followed by sudden infiltration of water into indoor spaces,' according to the report. It notes that dampness promotes dust mites, mold and other nasty microbes, supports cockroach and rodent infestations, and may cause building materials to decay or corrode, leading to offgassing of chemicals. Efforts to fight infestation could mean more exposure to fungicides and pesticides.
The report recommends that the EPA and other federal agencies, among other things:
- Help state and local officials prevent or lessen the impact of climate change-related indoor air quality problems on the most vulnerable people;
- Develop or refine measures for evaluating the health impacts of materials, furnishings and appliances used in buildings;
- Expand and accelerate efforts to review and, if necessary, change weatherization guidelines to prevent problems, and establish certification of weatherization contractors in procedures to protect health;
- Develop model health-based standards for ventilation in residential buildings and foster updated standards for commercial buildings and schools;
- Facilitate revision and adoption of regionally appropriate building codes that address the impacts of climate change;
- Make indoor environment and health issues 'an integral consideration in climate change research and action plans.'