Offices, schools, supermarkets and hospitals should be monitored for indoor air pollutants, according to England’s chief medical officer, amid concerns that dirty air in buildings may contribute to nearly as many deaths as outdoor air pollution.
Prof Chris Whitty said monitoring indoor air quality should become standard practice in public spaces and called for urgent investment to help establish records of pollutants that accumulate in homes, offices and public buildings.
While efforts to improve outdoor air quality have driven down emissions of particulates, nitrogen dioxides and sulphur dioxide, indoor air quality has largely been neglected. In buildings, air can be contaminated with fine particles from wood burners and cooking, and with noxious gases, cancer-causing chemicals, and pathogens such as viruses, bacteria and molds, all of which contribute to health problems.
Writing in the journal Nature, Whitty, Alastair Lewis, a professor of atmospheric chemistry at the University of York, and Dr Deborah Jenkins, a specialist registrar in public health at the Department of Health, call for a scientific push to understand indoor air pollution, with the aim of producing a “roadmap to cleaner indoor air.”
“Indoor air pollution hasn’t received the same attention [as outdoor air], even though it might cause almost as many deaths globally,” the authors write. The lack of research makes it hard for governments to target policies and controls, while building owners may be oblivious to the health risks and how to reduce them, they add.
Most people in industrialised countries spend 80-90% of their time indoors, in homes and offices or public spaces such as schools, shops, hospitals and transport hubs. But while indoor air contains a wider range of pollutants than outdoor air, reliable information on sources, concentrations, the harm they cause and ways to make buildings healthier beyond better ventilation is lacking.
The risks are shifting all the time. In England, coal burning, cigarette smoking, chemicals from paints, and nitrogen oxides from gas have all fallen in recent years. But volatile organic compounds from cosmetics and personal care products have risen, as have particulates due to the popularity of wood burners. Other concerns surround formaldehyde from building materials, brominated fire retardants in furniture, and radon from the bedrock beneath buildings.
One of the major challenges for scientists is that indoor air quality varies enormously with how buildings are built, ventilated, operated and occupied. According to Whitty, levels of volatile organic compounds can differ by a factor of 1,000 in identical houses on the same street, simply because people inside behave differently.
“Monitoring the indoor environment for pollution should become standard practice in public spaces,” the researchers write, adding that “indoor emission inventories need urgent investment”.
There are immediate actions people could take, at least in their homes, Lewis said. “You can do quite a lot, particularly with ensuring reasonable levels of ventilation. Unless you live in a highly polluted city, the outdoor air is going to be cleaner than that inside,” he said.
Prof Catherine Noakes, an expert in the spread of airborne diseases in buildings at Leeds University, said poor air quality affected productivity, school test scores and sleep quality, as well as asthma and infectious diseases. “Action to monitor the air in buildings is an important step that we need to take,” she said.
A recent report by the Royal Academy of Engineering found that improving ventilation in public and commercial buildings was cost-effective through reducing infections alone.
Dr Gary Fuller, an air pollution scientist at Imperial College London, said more must be done to tackle pollution at source. “We cannot control indoor air pollution by ventilation systems alone,” he said. “Many people cannot afford to upgrade their homes, and those in flats or rented homes have no options to change. Instead, manufacturers of products that we use in our homes need to accept responsibility for the air pollution that they create and work to reduce this.”
