WeeklySA_AdminCHILLS: It is nice to light an indoor fireplace for extra warmth or to have the occasional ‘braai’ – but the downside is that you may be inhaling tiny solid or liquid substances that could be harmful to your health…
By WSAM Reporterr
Indoor fireplaces – like braziers commonly used in informal settlements – could result in the release of harmful substances that can be dispersed in the air and cause health problems when inhaled – some settling in the lungs, while others can even enter the bloodstream.
These are the findings of a new study published in Energy Research and Social Science, a group of researchers from the Faculty of Engineering at Stellenbosch University (SU). The unit found that the downside of the habit of lighting an indoor fireplace for extra warmth during winter months or to enjoy an occasional braai was that the public might be inhaling tiny solid or liquid substances harmful to health.
The researchers point out that various studies have raised concern about poor indoor air quality in informal settlements, where fires are made indoors as a necessary measure for heating. However, its impact in formal housing, where fireplaces and indoor braais are commonly used as amenities, has not been investigated.
“Our results show that the levels of harmful substances released during indoor fireplace use exceeded the recommended guidelines and standards of the World Health Organization (WHO). The WHO recommends prolonged exposure to these small particles for no more than three days in a year,” says PhD candidate Rita van der Walt from the Department of Electrical and Electronic Engineering at SU.
“Prolonged exposure (months to years) to finer substances has been associated with early deaths, particularly among individuals with chronic heart or lung conditions, and stunted lung function growth in children,” adds van der Walt, who conducted the study with her supervisors and colleagues from her department and the Department of Industrial Engineering.
They looked at the air quality in a few houses that use open and closed indoor fireplaces during winter. “It is imperative to consider the effect of particles, released from an indoor fireplace, on the indoor air quality and the potential health risks associated.”
To collect air-quality data, they used sensing devices to measure and record the concentration of tiny particles in the air every 11 minutes – a total of 130 times daily. These sensing devices were placed on counters or tables near the fireplace.
“Our results suggest that the 24-hour average concentration of tiny particles often exceeds the WHO’s recommended limit of 15 micrograms per cubic meter (a space that is one meter long, one meter wide, and one meter tall). Fifteen micrograms is very tiny and lightweight. If you were to split a grain of table salt into four equal parts, one part would weigh 15 micrograms.
“The daily average exposure to these particles showed that, in all households measured, particle levels remained above the recommended limit for a long time after fireplace use. The results indicated periods ranging from slightly less than an hour to more than three hours of high exposure.
“The concentrations of these substances are only marginally higher for open fireplaces than enclosed ones.”
“However, when we compared the average levels of small particles between open and enclosed fireplaces, we found much higher and more unusual readings in homes with open fireplaces,” add the researchers.
During the study, they shared their findings with one of the households. “After sharing the preliminary measurements with one of the households who had an open fireplace, they immediately stopped making indoor fires. This resulted in a substantial reduction in the particulate concentrations and peak measurements.
“As many South Africans may not know about the health risks associated with using indoor fireplaces, these results might inform households on fireplaces and indoor air quality. Hopefully, this would reduce the number of indoor fires or get people to stop making them.”
The researchers say even though this was an exploratory study, it delivered valuable results laying the groundwork for a larger future study with more households. These households may include lower-income housing, where indoor fire-making becomes necessary for heating in winter, posing a potential public health concern.
They add that future work may also include conducting interventionist experiments that could involve making indoor air quality monitoring data available to households, potentially leading to proactive changes in behaviour and indoor environmental practices.
Africa faces some of the world’s most severe health impacts from air pollution – with five countries on the continent ranking among the ten most polluted countries in the world, according to a report by the US-based research organisation Health Effects Institute.
Those countries include Niger, Nigeria, Egypt, Mauritania and Cameroon, where the report, the State of Air Quality and Health Impacts in Africa, found fine particulate matter (PM2.5) exposures ranging as high as 65-80 micrograms per cubic meter (μg/m3), according to Health Policy Watch.
Some 1.1 million people in Africa died prematurely from air pollution-related diseases in 2019, one-sixth of the total global estimate of 7 million deaths annually. According to the report’s findings, air pollution is the second leading risk factor for premature deaths after malnutrition, placing it well above the long-discussed issues of unsafe water, sanitation and hygiene, which ranked fourth largest risk factor for deaths.
In 2022, the WHO warned that almost the entire global population (99%) breathed air that exceeded WHO air quality limits, threatening their health.
A record number of over 6000 cities in 117 countries were now monitoring air quality, but the people living in them are still breathing unhealthy levels of fine particulate matter and nitrogen dioxide, with people in low and middle-income countries suffering the highest exposures.
The findings have prompted the WHO to highlight the importance of curbing fossil fuel use and taking other tangible steps to reduce air pollution levels.
