Dr Hector Perera      London

When you think of pollution, you probably think of that layer of smog above the city or that gross black smoke that puffs in your face when the bus drives by. If you happened to be around Dehiwala by pass you will witness the three wheelers and even buses are climbing the Hill Street giving out streams of black diesel smoke fumes. Would you call that pollution? If you need to visit Dehiwala Zoo of course one has to go along Hill Street then turn off to another street where you would find the Sunday Pola” as well. I am not disputing about the how pollution might affect the food for sale in the Pola”. I like to visit these local food fairs where you get so many varieties of fruits, vegetables and even dry fish for sale. Who would like to taste an ice cream or a piece of pineapple in this kind of atmosphere? This is just a bit of atmospheric pollution. You want more?

Kitchen Pollution

Many kitchen appliances release colourless pollutants. Combine that with poor ventilation (which most homes also have), and your kitchen could be an invisible pollution haven. There is poor ventilation mainly in cold weather countries such as in California and England but in Sri Lanka, they always keep the kitchen windows wide open for proper ventilation.

Most of the people prepare their food in their home kitchen but there are plenty of people depend on nothing but takeaway food. There is no harm if you do not eat these takeaway food on regular basis.

Carbon monoxide (CO) is an odourless, colourless toxic gas. At high levels of exposure people can die, at low levels of exposure you could experience flu-like symptoms. Exposure for pregnant women can also have severe effects on the health of a foetus. Don’t forget sometimes the air conditioner as well give out carbon monoxide. Because of the hot weather some Sri Lankan homes have air conditioners which have to be checked for proper functioning.

Nitrogen Dioxide (NO2) is a reactive gas. According to the EPA, exposure to this gas has unclear results in the short-term, but it does irritate the lungs and could weaken resistance to respiratory infections. Nitrogen is a very unreactive gas but in high temperature it reacts with oxygen to form oxide of nitrogen which immediately reacts with more oxygen to form nitrogen dioxide. When the cooking temperature is very high, it forms this nitrogen oxide. I must say one cannot stop this totally but it can be controlled by using a moderately high temperature.

Particulate Matter (PM) are tiny particles of pollution that when inhaled can seriously affect the health of your lungs and heart. “Particulate matter,” also known as particle pollution or PM, is a complex mixture of extremely small particles and liquid droplets. Particle pollution is made up of a number of components, including acids (such as nitrates and sulphates), organic chemicals, metals, and soil or dust particles.

The size of particles is directly linked to their potential for causing health problems. EPA is concerned about particles that are 10 micrometers in diameter or smaller because those are the particles that generally pass through the throat and nose and enter the lungs. Once inhaled, these particles can affect the heart and lungs and cause serious health effects. EPA groups particle pollution into two categories:

“Inhalable coarse particles,” such as those found near roadways and dusty industries, are larger than 2.5 micrometers and smaller than 10 micrometers in diameter. “Fine particles,” such as those found in smoke and haze, are 2.5 micrometers in diameter and smaller. These particles can be directly emitted from sources such as forest fires, or they can form when gases emitted from power plants, industries and automobiles react in the air. Now have I got to say about our good old firewood stoves didn’t give out these PM matter?

Chlorofluorocarbons (CFCs) are gases that deplete the ozone layer, leading to global warming. A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, and fluorine, produced as a volatile derivative of methane, ethane, and propane. Cooking gas is methane so it is possible to form CFCs in the kitchen. CFCs can also harm your health causing headaches, dizziness and heart troubles. If you get these symptoms by being in the kitchen then you know why, it is due to inhaling these CFCs. I have seen some chefs go outside for a fag when they get a headache in the kitchen, how is that umpire?

Acrolein is a liquid or solid that is toxic to humans when inhaled or consumed orally. Acrolein (systematic name is propenal) is the simplest unsaturated aldehyde. It is a colourless liquid with a piercing, disagreeable, acrid smell. The smell of burnt fat (as when cooking oil is heated to its smoke point) is caused by glycerol in the burning fat breaking down into acrolein. The level of irritation depends on the level of exposure. I am sure most of you have experienced this smell when frying simple things such as papadams or dry fish in the kitchen. Also you might get this smell in takeaways shops where they fry far too many things.

Cooking on gas burners release nitrogen dioxide, carbon monoxide, particulate matter and acrolein, yes electric cookers give out less of these things.

Gas burners add an estimated 25 to 33 percent indoor NO2 in the summer and 35 to 39 percent in the winter (because of less ventilation). In the summer, gas ranges cause an estimated 30 percent increase in CO in the summer and a 21 percent increase in the winter when compared to electric stoves, according to a study conducted by Lawrence Lab and Stanford University researchers. The study, published in the January 2014 edition of Environmental Health Perspectives, analysed the summer and winter pollution concentration levels of 6,634 Southern California homes, half of which used gas stoves and half of which used electric stoves.

We fry far more different things such as fish and chips and chicken chips then different kinds of burgers. All these are involved with plenty of burning oils. When oils are burnt, it releases what is called acrolein. We know for fact that fats and oils are not quite healthy to eat on regular basis another reason is this acrolein.

Researchers now understand that the process of cooking food and even simply operating stoves particularly gas appliances can emit a cocktail of potentially hazardous chemicals and compounds. Within our homes, these pollutants are less diluted than they are outdoors, and in the absence of proper ventilation, they often are trapped inside. When the doors and windows are closed there is less ventilation. In cold weather countries the homes have less ventilation because of the cold weather but where as in hot countries like Sri Lanka the houses have plenty of ventilation so fresh air always circulate within the houses..

What is the killer in the kitchen?

According to research findings, nearly two million people die each year as a result of inhaling lethal smoke from kitchen stoves and fires. Most of these deaths are a result of respiratory infections. Most victims are women and children under five. Smoke is the killer in the kitchen. Try and avoid firewood cooking.

More than three billion people – half the world’s population – depend on fuels such as wood, dung and coal for cooking, boiling water and heating. Burning these fuels on rudimentary stoves or three-stone fires creates a dangerous cocktail of pollutants that can kill. It is the poorest who have to rely on the lowest grades of fuel, and are the most vulnerable. Every year smoke kills more people each year than malaria. I must say this firewood stoves are gradually disappearing even in rural areas in Sri Lanka due to availability of electricity and gas cookers. Honestly in the past we had nothing but firewood stoves in Sri Lanka for cooking. Your comments are welcomed perera6@hotmail.co.uk