Fine dust now appears to be deadly in the very short term, American researchers discovered. Many people over 65 die one day after being exposed to particulate matter.
Researchers at Harvard University put the death date of 22 million American over-65s (in the period 2000-2012) in addition to the particulate matter data in that period.
They noticed a clear connection. With an increase of the finest, most dangerous particulate matter (PM2.5, with a diameter of less than 2.5 micrometres), a day later clearly more people over 65 died, they report in the Journal of the American Medical Association.
An increase in the particulate matter concentration by 10 micrograms per cubic meter already increased the number of deaths by 1 percent. Up to 20 micrograms per cubic meter this increase continued, with higher concentrations the increase leveled off.
An increase in the ozone concentration also caused the number of deaths to increase, albeit less strongly with a rise in particulate matter.
Fine dust also appears deadly in the short term. Until now it was assumed that particulate matter was particularly harmful in the long term.
Measuring with cheap sensors is no solution but gives an indication of problems. They deviate 15-25% from real values.
Fine dust in Belgium and the Netherlands
In order to reduce the number of deaths among the elderly, the concentration should therefore remain well below 20 micrograms per cubic meter. Evidence for a safe lower limit has not been found by the Harvard researchers.
The EU sets the annual limit for PM2.5 particulate matter at 25 micrograms per cubic meter. The World Health Organization (WHO) is much stricter: an annual average of no more than 10 micrograms per cubic meter and no more than 3 peak days (days with more than 25 micrograms per cubic meter) per year.
Belgium and the Netherlands do not meet this WHO standard. In Belgium particulate matter concentrations have declined since 2000, but the decline has stagnated since 2015, according to figures from the Interregional Cell for the Environment.
Harmful to lungs and heart
Several studies have already pointed out the harmful effects of particulate matter on the lungs and heart. In May, British researchers found a direct link between the inhalation of PM2.5 particulate matter and heart damage .
Other recent studies found a connection with low birth weights and sleep disorders .
Last year, the WHO found that more than 80 percent of city dwellers worldwide are breathing too much particulate matter.
One of the most important causes of particulate matter is road traffic.