Indoor air pollution

The indoor environmental quality of urban buildings is seriously affected by the concentration of harmful pollutants in the indoor environment. Th sources of indoor pollutants are human activity, outdoor pollution and the presence of products and materials that emit a large variety of compounds. In developed countries, concentrations of indoor pollutants are very similar to those outdoors, with the ratio of indoor to outdoor concentration falling in the range of 0.7–1.3. However, the concentration of indoor pollutants may be two to five times higher than outdoor pollutants (WHO, 1999). According to United Nations Centre for Human Settlements, indoor air quality is inadequate in 30 per cent of the buildings around the world (LRC, 1993). Three basic strategies that may be used separately or in combination are proposed in order to reduce occupant exposure to indoor contaminants:
1 building air-tightening and pressure management;
2 ventilation and air filtration; and
3 contaminant removal (World Bank, 2000a and b).

Indoor air quality (IAQ) in developing countries is an extremely serious problem. While in developed countries IAQ problems arise from low ventilation rates and the emission of building products and materials, the inhabitants of LDCs face problems related to pollutants generated by human activities, particularly as a result of combustion processes through the use of ovens and braziers with imperfect kitchen and stove designs. As reported by Smith (1994): ‘Today about half the population of the world continues to rely for cooking and associated space heating on simple household stoves using unprocessed solid fuels that have high emission factors for a range of health damaging air pollutants.’ Compared to modern fuels such as gas, solid fuels produce 10 to 100 times more breathable particulate matter per meal (Smith, 1994). Measurements made in kitchens of homes in India showed particulate levels to be 35 times the 1-hour standard and nearly 100 times the 24-hour standard recommended in industrialized countries (IBGE, 1993). In parallel, other pollutants, such as carbon monoxide, formaldehyde,
polycyclic aromatic hydrocarbons, benzene, and 1,3-butadiene, also reach high concentrations. As reported by the World Health Organization (WHO), in some areas of China and India, the use of coal in houses leads to high indoor concentrations of fluorine and arsenic with consequent health effects (Smith, 1994).

High indoor concentration of pollutants poses a tremendous health threat to the population of the less developed countries. Worldwide, close to 2 million deaths per year are attributable to indoor air pollution from cooking fires (Serageldim et al, 1995). Recent studies by the WHO have shown that 30 to 40 per cent of 760 million cases of respiratory diseases worldwide are caused by particulate air pollution alone. ‘Mostly, these health effects are caused by indoor air pollution due to open stove cooking and heating in developing countries’ (WHO, 1997). Studies in Latin America, Asia and Africa have shown that indoor air pollution is also responsible for pregnancy-related problems, such as stillbirths and low birth weight. It has also been associated with blindness (attributed to 18 per cent of cases in India) and immune system depression (Schwela, 1996). In particular, in India, it is estimated that 500,000 women and children die each year due to indoor air pollution-related causes since almost 75 per cent of the population relies upon traditional biomass fuels (Schwela, 1996). This is close to 25 per cent of the deaths worldwide attributed to indoor air pollution problems.

Other studies increase the number of premature deaths in India because of indoor air pollution problems to 3.3 million per year. Table 1.3 summarizes most of the recent estimates on premature mortality in India due to indoor air pollution problems. The severity of the problem is shown by studies that estimate the burden of disease in India for selected major risk factors and diseases. As shown in Figure 1.4, mortality due to indoor air pollution problems is very high. It is evident that proper ventilation of urban buildings in these countries, as well as in the developed world, can contribute significantly to reducing the concentration of indoor pollutants and to protecting public health. Given that indoor pollution problems in LDCs primarily affect the poorest sector of the population, the use of advanced ventilation and filtration techniques is not feasible at all. Thus, natural ventilation may be an effective solution if outdoor air quality is less polluted than indoor air quality. The development of appropriate strategies and techniques to enhance natural ventilation in urban buildings may save million of lives in developing countries.

تلوث الهواء الداخل للمنزل او اي بيئة ممكن يسبب هواية مشاكل اني اخر موضوع قريته عن تلوث الهواء انو يسبب ارتفاع بضغط الدم بالاخص للناس الي تطبخ باستعمال الحطب و حتى التدفئة همات بالخشب والحطب
اتصور هيج نوع من الطبخ بعده ماشي بالقريات
تحياتي د. هناء

thank you dr.
good info.