Studies have shown that carbon monoxide (CO) poisoning can lead to fainting, hospitalizations and even death from brain and cardiovascular complications. In 2022, 457 emergency calls and 26 consequent deaths were associated with CO poisoning in Ulaanbaatar. In January 2023, in the middle of the coldest month of this year, there were 39 emergency calls for CO poisoning within just three days, three of which resulted in death. 61 percent of households from Breathe Mongolia’s “Let’s take action!” project are constantly worried about CO poisoning; it is evident that households using coal stoves are well aware of this danger. 

The question is, “How long does it take for such carbon monoxide poisoning to show?”. CO combines with red blood cells 210 times more easily than oxygen to form a compound called carboxyhemoglobin, and severe symptoms including fainting and hospitalizations start to appear when CO levels reach more than 20 percent in the blood. This is equivalent to CO exposure of 500 parts per mission (ppm) for approximately one hour. Carboxyhemoglobin disseminates through  the body via  the blood circulation, causing a lack of oxygen in the body’s tissues. 

In particular, CO is known as a neurotoxin. The gas can pass through the placental barrier and reach fetal circulation and the developing brain. Therefore, CO is considered one of the greatest public health threats, significantly affecting children’s neurodevelopment.

When carboxyhemoglobin is less than 20 percent, symptoms such as headache, fatigue, and lethargy appear, and if it is less than 10 percent, there are no symptoms. In fact, studies have shown carboxyhemoglobin blood levels can reach up to even 15% in smokers without any resulting symptoms. Thus, while one might not be acutely poisoned or hospitalized from smoking or burning fuel in the home, chronic exposure to CO can poison your body over time. And since the gas is odorless and colorless, it is impossible to identify this chronic exposure until one begins to show severe symptoms.  

CO sensors were deployed in 28 households in November 2022 under the scope of Breathe Mongolia’s “Let’s Take Action!” project.

Chronic exposure to low concentrations of CO can have adverse health effects both in the short and long term. At the beginning of the “Let’s take action project”, we deployed CO sensors in the homes of all participating 28 families in collaboration with Binary Systems Co. ltd and conducted a baseline survey including chronic CO exposure signs among all children in November, 2022. 

In the first survey period conducted in November 2022, 24-41 percent of all the 67 children of these families reported chronic carbon monoxide exposure signs, such as chest pain, flu-like symptoms, and headaches. This shows that subclinical carbon monoxide poisoning might be occurring in approximately one-third of all children. 

In addition, other common signs linked with other sources of indoor air pollution, such as coughing during sleep, are present in 35 percent, and difficulty breathing indoors, is present in 33 percent of the children. Respiratory illness occurred in 70 percent of all children in November 2022. Although there are many driving factors, it can be seen that the quality of daily life of children living in ger areas is decreasing due to respiratory illness induced by indoor air pollution.

Using combustion appliances for heating or cooking indoors can create favorable conditions for continuously releasing CO gas –  this is evident in the preliminary data collected from the “Let’s take action” project. The research team successfully deployed a network of 28 stationary CO monitors in the Ulaanbaatar area. Based on the data, it was found that the families taking part in the study are regularly exposed to CO gas levels three to four times higher than the Mongolian hourly exposure threshold of 30 ppm, as shown in the figure below.

Another primary source of CO is cigarette smoke. CO levels within smoking rooms can reach 35 ppm. Half of the Mongolian households have at least one person who smokes. In 2016, a population-based study in Bulgan revealed that 80 percent of all smokers smoke at home. Smoking at home and poisoning people you live with is more harmful than smoking yourself because being next to a person who smokes exposes one not only to the smoke from the combustion of cigarettes but also the smoke inhaled and exhaled by the smoker’s breath. Although 64 percent of the households participating in the “Let’s take action” project had someone who smokes, reflecting the population data, only two of the participants smoke at home.

Hourly CO emissions in 28 families from November 2022 to January 2023.

In 2019, a study found that 33 households in five districts of Ulaanbaatar city had indoor CO levels that were consistently above the exposure threshold. While the study revealed that the median CO level was lower in homes with coal briquettes compared to raw-coal burning homes, the authors conclude that broader impacts of fuel use behavior on CO concentrations should be explored. Our “Let’s take action” project explores these complexities, as we aim to measure whether installing the CHIP package lowers acute and chronic exposure to CO. 

No matter how bad the air in the city is, if you can reduce the concentration of CO by abstaining from burning fuels in the home and smoking indoors, you can prevent numerous health issues. We believe that if we can reduce the adverse effects caused by chronic CO poisoning to the children of the participating families of the “Let’s take action” project, we can increase the chances of their future success in life.

Edited by: Enkhuun Byambadorj, Azjargal Tsogtsaikhan