Cooking in a gas hob can create a higher level of indoor air pollution than you would expect from one of the UK's busiest roads.
Research by Which one? The levels of two levels of the most harmful air pollutants (nitrogen dioxide (NO2) and particulate matter (PM2.5)) were compared.
NO2 is a huge contributor to children with asthma, and exacerbates other breathing conditions in children and adults.
PM2.5 is associated with the worsening or development of several diseases, including respiratory disease, lung cancer, increased risk of heart disease, and Parkinson's disease.
This study, conducted in November 2024, found that the level of NO2 from the gas hob increases along the amount of cooking time and the number of gas rings used. Even if you use one ring NO2 to slowly cook your meals, it will be more than doubled.
When the NO2 level was spiked, it turns out that the researchers remained up for quite some time. Often it's a few hours.
The study suggests that spending the night in the same room as people cooked can be exposed to sustained levels of harmful contaminants well beyond World Health Organization (WHO) guidelines.
Volunteers using the induction hob experienced a background level of NO2, primarily from outdoor contamination.
Under investigation, which? The Marylebone Road office reached 33 micrograms per cubic meter, but on a 24-hour average of PM2.5 was 14 micrograms per cubic meter.
In contrast, three volunteers using Gas Hob experienced several PM2.5 peaks of over 100 micrograms per cubic meter, with one volunteer experiencing a peak of nearly 650 micrograms per cubic meter. The average WHO 24-hour guidance limit is 15 micrograms per cubic meter.
Which one? The researchers calculated that one household averaged more than the four-day WHO PM2.5 guidance limit, while the other two homes exceeded the two-day limit.
PM2.5 base levels recorded prior to cooking ranged from less than 1 microgram per cubic meter to about 20 microgram per cubic meter.
In one scenario, volunteers checked the air quality in the living area if the adjacent room or home is open plan.
Both NO2 and PM2.5 levels still reach high peaks, with levels rising for a few hours after cooking indicating that contamination spreads rapidly into the home.
The PM2.5 level returned to the level recorded before cooking within 45 minutes of opening in three of the five homes.
Which? A survey of more than 2,000 UK adults on air pollution showed little awareness of the dangers poses from cooking. Only a quarter of people with gas hobs said they are worried that it could affect their health.
a Research published last October We found that NO2 exposure to gas cooking in the UK costs £15.1 billion a year and is associated with the premature deaths of around 4,000 people per year.
Dr. Monica Mateo Garcia of Birmingham City University's Future Home Centeradvised consumers to use extractor fans to go outside and open windows and doors while cooking, which helped “fast collapse of indoor pollutants.”
Christian Pfrang, Professor of Atmospheric Science at the University of BirminghamHe also advised consumers to always use extractor fans when cooking. Research shows that many people are not.
He warned that if indoor contamination was not removed quickly, for example, it would be spread out into bedrooms where people might spend more time.
“They may spend 20 minutes cooking, but then they may be exposed to an eight- or nine-hour level rise, which can cause health problems, especially in vulnerable or elderly people or children,” he added.
