One study found that exposure to ultrafine pollution particles can trigger heart attacks. The research showed that there was an increase of 3–6 percent in nonfatal heart attacks 6 hours after exposure to this type of pollution.
A clear link exists between air pollution and different health conditions, with children particularly susceptible to injury. Pollution is causing one-third of all deaths from stroke, lung cancer and heart disease, according to the World Health Organization (WHO).
Ultrafine particles (UFPs) are of particular interest to researchers with evidence that they could be essential to pollution’s negative health impacts, particularly in respiratory health. The reason is its very small size, its large surface area relative to its mass, and its ability to enter the bloodstream.
In urban areas, the predominant source of UFPs is the combustion of petrol or diesel in cars and other cars— with their exhaust fumes coming into the surrounding environment.
As a result, some cities around the world are attempting to drastically reduce the number of vehicles that can drive into their centres. This not only decreases air pollution but also noise pollution and greenhouse gases, according to a study in the journal Environment International; it also promotes more active forms of travel, such as walking and cycling.
UFPs affect heart health
The most recent study, published in Environmental Health Perspectives, looked specifically at the impact of UFPs on heart health. While researchers have suspected a relationship exists between UFPs and heart health, before this study, scientists could not clearly demonstrate the link.
According to Kai Chen, Ph.D., assistant professor at Yale School of Public Health in New Haven, CT, and the first author of the study:
“This study confirms something long suspected— the tiny particles of air pollution can play a role in serious heart disease. In the first few hours of exposure, this is especially true. High UFP rates are a serious concern for public health.’
Annette Peters, director of the Institute of Epidemiology at the Helmholtz Center Munich in Germany and co-author of the paper adds: “In an epidemiological study in the 1990s, we were the first to show the impact of UFP on asthmatic safety. About 200 more studies have since been released. Nevertheless, epidemiological evidence remains contradictory and inadequate to suggest a causal relationship.”
The authors assume the uncertainty is attributable to the many different ways that scientists can evaluate UFPs in previous findings. For instance, various groups might look at their scale, surface area, or quantity. Furthermore, results change depending on how researchers define UFPs. The authors of the latest study accounted for many of these variables in their research.
Air monitoring sites
The team looked at the data from air pollution monitoring sites in the German city of Augsburg between 2005 and 2015 to assess the relationship between UFPs and nonfatal heart attacks.
They then applied this to data on non-fatal heart attacks in the city over the same period, updating their results to account for a number of other factors that could also lead to an increase in non-fatal heart attack.
The researchers found that there was a correlation between increased UFPs and the rate of non-fatal heart attacks, particularly in the first few hours after particle increases. This increase in heart attacks ranged from just over 3% to almost 6%, depending on how they measured the particles.
The study could only look at non-fatal heart attacks since there was no information available on the timing of fatal heart attacks. However, they note that the authors found no difference between fatal and nonfatal heart attacks in another study which looked at daily levels of UFPs.
“This represents an important step towards understanding the appropriate indicator of ultrafine particle exposure in determining the short-term health effects,” commented Prof. Chen, adding, “because the effects of particle length and surface concentration were stronger than those of particle number concentration and remained similar after adjustment for other air contaminants.”
To take the study further, Prof. Chen explained that future analyzes would look at both air pollution and high temperature combined hourly exposures.
“As for pre-existing illnesses and the consumption of drugs, we will also recognize susceptible subpopulations,” he concludes.