In an article from scidev.net, they talk about an article that was posted in a medical paper around indoor air pollution causing a number of different diseases, and ultimately causing 4.3 million deaths in 2012. Indoor air pollution is mostly found in developing countries because of the lack of innovation and money for home appliances. Certain stoves and heaters that are used in households is said to be increasing both children's and adults risk of chronic obstructive pulmonary disease, which is a disease usually found in people who smoke.
The study found the disease mostly in young children and women from Africa, Asia, and the Middle East, and this is because they are spending the majority of their time in the household breathing in fumes. Although they offer some solutions toward the end of the article, in the end it is really going to come down to these families being able to afford safer appliances for their homes, or potentially some sort of better ventilation system that doesn't cause the fumes from the stove and the heater to circulate throughout the house.
For more information on this study, visit http://www.scidev.net/global/pollution/news/indoor-air-pollution-kill-4-million-year.html.
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