ارزیابی ترکیبات آلی فرار در هوای شهر خرم آباد و مقایسه آن با استانداردهای موجود

Background : The first step in controlling pollutants is to measure and analyze them, because comparing them with standards and practically controlling them will not become possible without full awareness of the qualities and quantities of pollutants. The present study was conducted to assess and determine the amount of volatile organic compounds in the air in Khorramabad, Iran. Methods and Materials: The present research is a descriptive study. On the whole, a total of 144 samples were randomly taken from the air in Khorramabad during one year. Sampling was done through an environmental sampling pump and activated carbon absorbent tubes. The sampling method the continuous random 24-hour type. The preparation of the samples and the extraction of the pollutants were carried out by solvent carbon disulfide. The samples were analyzed using Gas Chromatography – Mass Spectrometry (GC-MS) device equipped with capillary columns. Data analysis was conducted using SPSS 17 and t-tests. Results: The results of the present study showed that the total concentration of the volatile organic compounds (VOCs) in the air of Khorramabad was 1140.9 µg/m3, which was about 7 times greater than the maximum acceptable amount set by USEPA (United States Environmental Protection Agency). Additionally, the findings of the present research indicate that, totally the mean concentration of all volatile organic compounds in different areas of the city of Khorramabad was higher than the permissible level set by EPA for breathable air. The comparison of the mean concentration of VOCs in the air in Khorramabad in the warm and cold seasons using the t-test indicated that there is a significant relationship between the concentrations of benzene and toluene and the season of the year (p < 0.05). But for the other identified hydrocarbons no significant relationship was found despite the fact that they have higher concentrations during the warm season. Conclusion: Regarding the results of this study which indicated that the concentration of the VOCs in the air of Khorramabad is seven times greater than the amount set by international standards, it can be concluded that taking action to prevent the contamination of the air in Khorramabad is absolutely essential and calls for the design of an appropriate management system, proper planning, a continual monitoring system, and enhancement of the level of awareness of the people.