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Chemical air pollution in dwelling as a health risk factor

Up-to-date techniques applied in physical-chemical studies made it possible to identify and quantify chemical pollutants in the air inside contemporary dwelling in a large megacity and then create a database on them. This database has a list of more than 600 chemicals from 18 groups of volatile hydrocarbons and covers hygienic standards for their contents, their hazard category, and ranges of detected concentrations. Major sources of air pollution with these chemicals in dwelling were also identified. From the hygienic point of view, a significant fact is that there are no hygienic standards for more than 60 % of chemicals detected in air in dwelling. Formaldehyde, phenol, and styrene are priority chemicals for quality monitoring and risk-based control of hazards posed by chemical air pollution both in newly built houses that are at the approval stage and already exploited ones. Formaldehyde, benzene, phenol, styrene, acetophenone, ethylbenzene, hexanal, nonanal, butyl acetate, ethyl acetate, isopropanol, and trimethylbenzene are the most hygienically significant volatile organic compounds for quality control and health risk assessment considering frequency of their occurrence, concentration levels, concentrations exceeding MPC, group affiliation, hazard category, and ability to transform. When controlling natural chemicals that occur in air in dwelling due to some internal pollution sources, we should bear in mind that transformation may result in a new structure of pollution and new occurring chemicals can be more toxic and hazardous than original ones. To minimize risks associated with exposure to chemical pollution and to assess chemical safety of air in dwelling, we recommend wider use of up-to-date physical and chemical methods for qualitative and quantitative analysis thereby securing identification of a wide range of pollutants including potentially hazardous ones. Since certain chemicals have been detected for which no safety criteria have been developed so far, it is especially vital to perform research in the sphere of hygienic standardization and to develop methodical documents aimed at providing adequate hygienic assessment of quality and chemical safety of internal environment in dwelling.