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- Title
İstanbul atmosferinde Polisiklik Aromatik Hidrokarbon konsantrasyonunun belirlenmesi.
- Authors
Hanedar, Asude; Alp, Kadir
- Abstract
Polycyclic aromatic hydrocarbons (PAHs) are semivolatile organic compounds consisting of two or more fused aromatic rings. These compounds are produced in the atmosphere as by-products of the incomplete combustion of almost any fuel. After emitting the atmosphere, this pollutants fallout to the ground as dry or wet deposition depends on its form and many factors. The concentration of PAH in the atmosphere is in the order of ng/m3. Atmospheric PAHs are partitioned between the particulate and the gaseous phases. PAHs have received increased attention in recent years in air pollution studies because some of these compounds are highly carcinogenic or mutagenic. Some PAHs were classified as probable or possible carcinogens to humans. For this reason, especially after 1980’s years, concentrations of these pollutants have been monitored continuously, especially in water mass and atmosphere. In many metropolitans, concentrations and potential toxicity of PAHs to city ecosystem have been determined in monitoring network or individual studies. In the base of these monitoring programs, sources of PAHs identified and quantified at receptor locations with different techniques. This study is the first about atmospheric concentration of PAHs in Istanbul. In this study, 16 EPA`s PAHs and TSP (Total Suspended Solids) concentration were performed in three sampling stations for four seasons in the period of September 2006-December 2007 in Istanbul. Spatial and temporal profiles were determined and diagnostic ratios were applied for source apportiontment of the pollutants. Airborne samples were collected using PS-1 samplers with GFF filter to collect airborne particlebound PAH and TSP. The filter was followed by a glass cartridge containing polyurethane foam plug and XAD-2 resin. All sampled filters and glass cartridges were extracted by soxhlet method with nhexane: diethylether mixture for 20 h. The extract was then concentrated and cleaned up with silica gelcolumn using procedures by EPA. Analysis of all extracts were performed by means of reversed-phase HPLC using UV-visible and fluorescence detectors in series. A total of 326 airborne samples were collected and analyzed for 16 PAHs and TSP in the period at three monitoring stations; Yildiz (135 samples- urban site), DMO (129 samples-urban site) and Kilyos (62 samples-rural site). Total average PAH concentrations were 100.66±61.26, 84.63±46.66 and 25.12±13.34 ng m-3 and TSP concentrations were 101.16±53.22, 152.31±99.12, 49.84±18.58 μg m-3 for Yildiz, DMO and Kilyos stations respectively. When comparing average concentration, maximum PAH values were observed for Yildiz station but maximum TSP values were observed for DMO station. At all the sites, the lighter compounds (MW<200) were the most abundant species. Nevertheless some reduction was observed in percentage of the low molecular weight PAHs during the warm season for all stations. Because PAHs with high molecular weight are found mainly adsorbed in particulate matter, a good correlation between TSP and heavier PAH concentration is expected. In general, correlation values between TSP and total heavier PAH values were good for Yildiz and DMO stations. Averagecorrelation values were 0.60 and 0.56 for Yildiz and DMO stations respectively. The pattern of PAH and TSP concentrations showed spatial and temporal variations. Strong seasonality was observed especially for urban stations. The highest level was observed in winter in urban areas while the lowest in summer in rural area. When comparing seasonal values, Winter 2006 had the highest PAH levels for all stations and the lowest levels were observed in Spring and Summer 2007. Comparing yearly variations, year 2006 had bigger PAH values than year 2007. PAH concentration values were compared literature studies. The comparison of the results with the examples given in the literature was in a good agreement. The concentrations or ratios of specific PAH compounds have been used to indicate towards the corresponding emission sources, especially for vehicle emissions In the study, PAH concentration values were analyzed with diagnostic ratios. The ratios of PAHs were compared with individual concentration values in order to determine sources of PAHs. Yildiz and DMO sites was affected by traffic-related sources, and diesel emission sources had higher contribution than gasoline ones. On the other hand, low level traffic emission was obtained for Kilyos station as expected.
- Subjects
UNITED States; ISTANBUL (Turkey); TURKEY; POLYCYCLIC aromatic hydrocarbons &; the environment; TOTAL suspended solids; EMISSIONS (Air pollution); AIR pollution; HIGH performance liquid chromatography; UNITED States. Environmental Protection Agency
- Publication
ITU Journal Series D: Engineering, 2010, Vol 9, Issue 6, p15
- ISSN
1303-703X
- Publication type
Article