Using low-cost indoor air purifiers may help protect at-risk people from the adverse health effects of air pollution, a study claims.
Microscopic particles floating in the air we breathe come from sources such as fossil fuel combustion, fires, cigarettes and vehicles, said researchers from the University of Michigan in the US. Known as fine particulate matter, this form of air pollution increases the risk of cardiovascular and other serious health problems, they said.
The study, published in the journal JAMA Internal Medicine, found three days of using a low-cost air purifier at home significantly lowered urban seniors’ fine particulate matter exposure. It also significantly lowered their blood pressure, which is the leading cause of morbidity and mortality worldwide, researchers said.
“The results show that a simple practical intervention using inexpensive indoor air filtration units can help protect at-risk individuals from the adverse health effects of fine particulate matter air pollution,” said Robert Brook from the University of Michigan. Forty seniors participated in this randomised study. Ninety-five per cent of the participants were black; all were nonsmokers.
Each person experienced three different three-day scenarios: a sham air filter (an air filtration system without a filter), a low-efficiency air purifier system and a high-efficiency air purifier system. Participants went about their normal business during the study period and were allowed to open windows and go outside as often as they wished.
Blood pressure was measured each day, and participants wore personal air monitors to determine their personal air pollution exposure.
The researchers focused on reduced air pollutant exposure and lowered blood pressure over a three-day period as an indication of the portable air filters’ potential to be cardioprotective.
Brook said fine particulate matter exposure was reduced by 40 per cent, and systolic blood pressure was reduced by an average of 3.4 millimetres of murcury (mm Hg). Normal systolic blood pressure is considered less than 120 mm Hg and stage 1 hypertension begins at 130 and stage 2 at 140, researchers said.
“The benefits were even more marked in obese individuals who had 6 to 10 mm Hg reduction in systolic blood pressure,” said Brook.
Even a small investment could reap big benefits, researchers said. High-efficiency air purifiers reduced pollutant exposure to a greater degree, but they didn’t lower people’s blood pressure more significantly than low-efficiency air purifiers, they said.