Photograph by Lasse Bergqvist
Since the discovery of fire, cooking has conquered a primary role in our lives. The first form of cooking started 2 million years ago with the throwing of a chunk of food into the fire. According to Anthropologist Richard Wrangham, it was a spontaneous gesture that led to the discovery of a new human experience.
We’ve come a long way since that moment. It was indeed the development of numerous cooking techniques and abilities that allowed our brains to grow and evolve.
The introduction of gas stoves
Whether you cook for pleasure or work, the cooking main role is survival, and you may like it or not, is one of those activities we do every single day. Although it may seem an undemanding practice, cooking involves different items: various cutlery for preparation and different types of stoves for cooking. Since wood and coal were used to ignite the fire, stoves have developed enormously. It was indeed the 1880s and 1890s that saw the introduction of gas stoves. Designed by English Engineer James Sharp, gas stoves were a great improvement because of the flame burning only when the stove was in use. Today cooking stoves range from gas stoves to electric stoves, or even the more recent induction cooktop and downdraft cooktop.
Although cooking practices involve a great amount of amusement, relaxation, and practical skills, they also produce indoor air pollution. This has a great impact on our daily activities. Since the world has been staying at home more lately, our exposure to indoor air pollution has increased tremendously, and sometimes the consequences of it are ignored or simply not known by everyone.
If it’s true that stoves have changed and become safer for our health, gas stoves are still used in large amounts in the world. Poor-developing countries still use solid fuels for cooking, burning for instance wood and charcoal on an open fire and inhaling at the same time all the fumes produced. The inhalation of cooking fumes and the effects on our health are still not taken seriously. However, they contain toxic substances, such as Particulate Matter and HCA, that make cooking dangerous for our health.
Why is cooking dangerous
Even if cooking could seem a harmless activity, it’s extremely easy to reach high temperatures while preparing any sort of food. And despite the good smell, when high temperatures are involved, millions of toxic substances are released. More if we burn food even slightly.
What is PM
PM, or Particulate Matter, is a mix of liquid droplets and solid particles found in the air that differ in dimensions. They can be formed by different chemicals. Researchers have been studying the correlation between Particulate Matter (PM) and cooking activities and they found out that exposure to an elevated amount of PM2.5 could damage human respiratory systems and lead to premature death. In addition, the level of danger related to emissions would vary according to four different conditions: stove type, cooking method, oil type, and food type.
What is HCA
As regards food type, research has focused on emissions produced by frying beef (hamburgers), pork (bacon strips), and soybean-based food. Frying beef and pork were found to be mutagenic and the three types of food had the following amounts of HCAs in the smoke: 3 ng/g from fried bacon, 0.37 ng/g from fried beef, and 0.177 ng/g from fried soy-based food. These results indicated that prolonged exposure could provoke long-term consequences.
HCAs acronym stands for heterocyclic amines, chemicals that form when beef, pork, fish, or poultry are cooked at high temperatures. These chemicals cause a change in the DNA and are carcinogenic. HCA formation depends on meat type, cooking method, and on how done the meat is. Indeed, cooking meat for a long time means the release of more HCAs.
Photograph by Emerson Vieira
Indoor air quality gets compromised by cooking activities, and a great range of studies have been researching in the field to get to know better how this practice affects human health. Results have shown that the total concentration of PM in the smoke was 1.9-5.3 times higher during cooking compared to other activities and that some kind of food, such as pork, tend to be more toxic.
But what are the risks for our health?
According to the WHO, illness caused by air pollution from cooking causes the premature death of 3.8 million people each year. These numbers are alarming if we consider that influenza causes 36.000 deaths each year. The main causes of death are pneumonia (27%), ischemic heart disease (27%), chronic obstructive pulmonary disease (20%), stroke (18%), and lung cancer (8%). However, PM and other pollutants-related symptoms include inflammation of airways and lungs and nasopharyngeal and laryngeal cancers.
A group of researchers carried out a study on the risk of lung cancer among cooking adults and found out that cooking oil fume could represent a risk factor for lung cancer.
That’s why we should always keep in mind some basic instructions to avoid inhaling high quantities of chemicals while cooking our daily meals.
How to reduce kitchen pollution
Cover the cooking pan while cooking and use the back burner
Covering the cooking pan is a great way to reduce PM emissions and avoid inhalation. Another way to reduce emissions is using the back burner. As a matter of fact, back burners are more exposed to ventilation than closer burners, which tend to diffuse emissions more.
Clean the burner before and after use
Although we don’t always have the time to clean the burners, you should always avoid cooking with dirty burners. Cooking with food debris attached to burners means burning old food and consequently increasing the emission of PM and toxic substances that are mostly carcinogenic.
Avoid burning food
Cooking at high temperatures or letting food cook too much can lead to burning food. Despite tastes, burning food is more dangerous than you think. The reason is simple: when we cook at high temperatures, acrylamide, a particular molecule is formed. Acrylamide is considered to be carcinogenic by the International Agency for Research on Cancer (IARC). Boiling instead of frying could be an alternative to avoid burning food. Indeed, research highlighted how acrylamide couldn’t be found in boiled food, while was found at higher temperatures and with other cooking methods.
Turn on the exhaust fan
Zhang et al. measured ultrafine particle (UFP) formation during indoor cooking activities and found out that cooking styles and cooking emissions are strongly related. Indeed, UFP levels were higher during frying than boiling, and when food was cooked at higher temperatures. In addition, they noticed that using an exhaust fan could decrease emissions by a factor of 2.
The graph shows the UFP distribution as a function of time, divided into 8 different cooking conditions. The elements taken into consideration are the use of electric stove vs gas stove; medium vs high heat; fan on vs fan off. The different colors presented in the graph indicate the particle number concentration for a given particle size at a given time. The study reveals that UFP concentrations were at the highest level using a gas stove at high temperature with the exhaust fan not in use.
Use the exhaust fan also before cooking
As a form of prevention, you should always use an exhaust fan when cooking. Indeed, ventilation is useful for decreasing PM levels in the atmosphere. However, not everyone knows that the exhaust fan should be turned on also before cooking. As a matter of fact, turning on the exhaust fan before preparing your meal guarantees a good ventilation flow before cooking. But you should turn it on also right after, to reduce the diffusion and accumulation of toxic substances in your indoor spaces.
Use multi-sense air quality monitors to control HVAC systems automatically
As we have seen, kitchen ventilation becomes essential in reducing VOCs, PM and other substances emissions. However, our daily lives are often so busy that there’s a chance of forgetting to ventilate our homes properly. An easy and accurate way to control VOCs, PM emissions, and indoor air quality is to use smart ventilation systems. These systems, smartly connected to Airgloss Prosense, detect volatile organic compounds, PM, carbon dioxide, and carbon monoxide in the air, and automatically driving ventilation to keep the level of pollutant below the critical threshold.
New generations of hoods have smart devices that can automatically control ventilation when you forget to do it yourself. Airgloss OEM can be found in some of the highest-quality hoods and can activate them in the blink of an eye.
Raise awereness
As already highlighted in our previous articles, indoor air quality has a major role in our health. Indoor air quality remains fundamental to protect ourselves from numerous risks that could dramatically endanger our well-being and daily life.
At the same time, we should be able to prepare our meals with the lowest risk for our health involved.
That’s why raising awareness and monitoring indoor air quality is key.