Study on Evaluvation of Benzo (a) Pyrene Soluble Fraction in Respirable Suspended Particulate Matter in Peenya Industrial Area by GCMS

Polycyclic aromatic hydrocarbons (PAHs) were identified to be one of the major toxic air pollutants in urban environment. PAHs are mostly formed during incomplete combustion or pyrolysis of organic material. According to National ambient air quality Indian standard, benzo (a) pyrene (BaP) concentration Part iculate matter (PM10) in ambient air in the Peenya industrial area Bangalore metropolitan in India has been determined. Air samples for the analysis of BaP in suspended particles have been collected (as 24 h sample once in a month) at selected monitoring sites within the Peenya industrial monitoring network. In this research work, the results of PM10 were collected between February 2011 and April 2011. The Benzo(a)pyrene concentrations of the eight sampling sites ranged from zero to 0.0490ng/m. Spatial variations were predominantly due to the different strengths of source emission. The total Benzo(a)pyrene concentrations at Kongovi Monitoring Station site was higher than those at other seven sites during monitoring period, observing the results obtained during the period of a whole year, it was concluded that, the concentrations of BaP were much h igher during winter season at almost all measuring sites.


Introduction
Polycyclic aro matic hydrocarbons (PAHs) are products of incomp lete co mbustion formed during burning or pyrolysis of organic matter such as coal, oil, bio mass, gasoline [1] and diesel [2,3]. Also PAHs in ambient air can be emitted fro m industrial co mbustions [3,4], alu minu m production, cement manufactu re, p roduct ion o f coal t are, co ke and asphalt, p etro leu m c ata ly t ic cr ac k in g an d res tau ran ts [ 5 ]. Atmospheric PAHs can exist in both gaseous and particle p has es , wh ile a g reater fraction o f airbo rn e o rg an ic particu late matter is present in the respirable size range. Some studies found that PAHs with two or three benzene rings exist in the vapour phase, while PAHs with mo re than five rings were observed primarily in the part iculate phase [6]. Th is s ugg ests that p articu late PA Hs are regarded as significant hazardous substances to hu man health when introduced through the skin or through the lungs or ingestion. A ir p o llution has adv ers e effects o n res p irato ry and card iovascu lar systems such as acut e reduct ion in lung function, aggravation of asthma, increased risk o f pneu monia to the elderly, lo w birth weight and high death in newborns [7,8]. Particulate matter have been suggested to pose a great risk to hu man health due to their high number concentration in urban environments and potential to penetrate (ultrafine particulate) fro m the lung alveoli into the blood circulation [9]. The chemical co mposition of airborne particulate matter (PM) in polluted atmosphere has become a topic of considerable importance over the recent years in relation to public health [10,11]. Part iculate matter forms a highly comp lex mixture of different-sized solid and liquid particles [12][13][14]. Mass concentration may not be the most appropriate exposure parameter for the assessment of health risks of atmospheric pollution [15]. Many aromat ic compounds, commonly identified in airborne particles, are suspected genotoxic agents and carcinogens, and some of them may also cause acute health effects [16,17]. PAHs with four or more structural rings were concern treated on the fine and ultrafine particles, and various PAH investigations can be performed equally well fro m both the PM2.5 and the PM 10 samples [14]. Thus, inhalat ion of PAHs in part iculate mixtu re is potentially a serious health risk [18,19].
Benzo (a)pyrene has been regarded as one of the markers of the total and carcinogenic PAHs [7,14]. The Eu ropean Co mmission has set an annual target value of 1 ng/m 3 for benzo (a) pyrene in ambient air fro m content in PM 10 fraction, while current legislat ive in India set an annual limit value of 1 ng/m 3 for Ben zo (a) pyrene in RSPM. On the other hand, the natural background level of BaP may be near zero; in rural areas its concentration ranges fro m 0.01-1 ng/m 3 , in urban areas fro m 1-10 ng/m 3 .In o rder to estimate the carcinogenic risks for humans, the benzo(a)pyrene equivalent (BaPE) carcinogenicity was evaluated by mu ltip lying the concentrations of each PAH with their to xic equivalent factors (TEF) [20] which can be used to calculate the relative carcinogenicity of ambient samples with a known distribution of PA Hs.
In the present research work carried out the concentration of BaP in ambient air of the Peenya industrial area Bangalore, India and recorded at selected number of different types of sampling sites in period February 2011 to April 2011 has been evaluated for the first time. The PM10 samp les were collected fro m February 2011 to April 2011. The annual and seasonal BaP levels in RSPM samples in industrial area Bangalore were co mpared with BaP concentration National Ambient Air Quality Standards.

Experimental Section
The present research work gives a detail description of the adopted for various experiments.

Sampling Stations
Total Eight sampling Stations were selected for monitoring in Peenya Industrial Areas of Bangalore, India and the Table 1 shows the details of sampling stations selected for the study. Surya Hard Ch ro me Industry: The first location was Surya hard chrome industry which is located at first stage of Peenya industrial area. Th is area is surrounded by Electroplat ing, Chemical and Metal Ext racting industries and some Co mmercial shopping centres and Restaurants. This location is linked with 100 ft wide ring road wh ich is connected to Jalahalli cross and is characterized by heavy traffic.
Microtex Energy Industry: The second location was Microtex energy industry which is located at second phase Peenya industrial area. It is surrounded by Lead, Pharmaceuticals, Brewery, Text ile and Chemical industries. This area is characterized by moderate traffic.
Kongovi Electroplat ing Industry: The third location was Kongovi elecroplating industry which is located at second phase Peenya industrial area. This area is surrounded by Electroplating, Text ile, Pharmaceuticals and Lead industries. This area is characterized by moderate traffic.
Ace Designers Industry: The fourth location was Ace Designers industry which is located at second phase Peenya industrial area. Th is area is surrounded by Painting, Brewery, Pharmaceuticals and Metal industries and many Commercial shops.
Swan Silk Industry: The fifth location was Swan Silk industry which is located at third phase Peenya industrial area. This area is surrounded by Textile, Metal Plat ing and Chemical industry. It is also surrounded by partially residential houses and commercial shops etc and inter connected main roads.
Arun Industry: The sixth location was Arun Industry which is located at third stage Peenya industrial area. This area is surrounded by Oil and Grease industry, Smelt ing and Processing of Metal industries, Lead industries and BMTC work shop.
Naptha Resins Chemical Industry: The seventh location was Naphtha Resins Chemical industry which is located at fourth phase Peenya industrial area. Th is area is surrounded by Chemical, Metal and Steel industry and also surrounded by residential houses and commercial shops.
Triveni Turbine Industry: The eighth location was Triveni Turbine industry which is located at first phase Peenya industrial area. This area is surrounded by Turbine, Metal, Chemical, Text ile and Steel industries and also Metro work is in Progress. This location is connected to Jalahalli cross and is characterized by heavy traffic.

Meteorol ogical Condi tions
The Bangalore, India is endowed with a very salubrious and equable climate and hence classified as seasonally dry tropical savanna climate with four seasons. Dry-season with clear bright weather fro m December to February. The summer season is fro m March to May which is fo llowed by south-west monsoon season from June to September. October and November constitute the post monsoon season or retreating monsoon season. The Meteorological data needed was collected from Ind ian Meteorological Depart ment, Bangalore for the period February 2011 to April 2011.

Sampling
PM10 samp les were collected by Respirable dust sampler. The Respirable Dust Sampler was introduced by Envirotech with technology fro m Nat ional Env iron mental Engineering Research Institute (NEERI) Nagpur in 1992. The periods were fro m February 2011 to April 2011, respectively. All filters were maintained in a condition of 50% RH and 25℃ for over 48 h and weighted before sampling. The Respirab le Suspended Particulate M atter in Peenya Industrial Area by GCM S dust samplers were operated at flow rates of 0.9 -1.2 m 3 / min. PM10 collected on 20.3 cm×25.4 cm What man quartz micro fiber filters. The Respirab le Dust Sampler has a unique flow measuring system using an orifice plate incorporated into the body of the Filter Adopted Assembly ensures exact measurements of the air passing through the filter, without any leakages or extraneous air flows, affecting the flow readings.. PM10 samples were collected for 24 hours.

B(a)P Analysis
RSPM-BaP samp les were prepared according to Co mpendiu m Method TO-13A [21], determination of PAHs in amb ient air using GC/MS. A ll samples were extracted using a Soxhlet extractor with a solvent solution of 250 mL (a mixture o f 125 mL n -hexane and 125 mL acetone) for 18 h. The obtained extracts were then concentrated to 1 mL using a rotary evaporator and cleaned up on the colu mn with 10 g activated silica gel and sodium sulfate on the top of the column. The co lu mn was rinsed with 60 mL dichloro methane and 40 mL pentane. The collected extract was rejected and, when the level of the pentane layer was above the sodium sulfate, 1 mL of sample extract was applied to a column. The column was rinsed with 25 mL of pentane, fractioned with pentane containing aliphatic hydrocarbons, and it was rejected. Colu mn rinsing was continued with 25 mL of methylene chloride: pentane (4:6) mixtu re. The ext ract was then concentrated using a rotary evaporator with 100 μL toluene as keeper, solvent was exchanged to toluene until 0.5 mL and analy zed on GC/MS. PM10-BaP samp les were extracted with solvent solution of 50 mL (a mixtu re of 12.5 mL hexane and 12.5 mL acetone (1:1) in mu ltiwave 3000 with rotor 8SOLV and cleaned up the same way as PAH-RSPM. The obtained ext racts with 100 μL toluene as keeper were concentrated using the rotary evaporator to 0.5 mL and analy zed on GC/M S. Benzo(a) pyrene was determined using an thermo scientific gas chromatograph mass selective detector and capillary colu mn DB-5 MS l, 30m 0.25 mm,25 μm. The oven temperature was programmed to be fro m 70°C at a rate of 8°C/ min to 310°C and held for 5 min with heliu m as the carrier gas. Se mi-internal standard was used (deutered PAHs) for internal calibration. Prior to analysis, a calibrat ion curve for the benzo(a)pyrene was obtained by spiking seven known quantities of substance with an R2 of the calib ration curve above 0.95. With each set of samples, both field and laboratory blank samples were prepared and analyzed together with the samples. Benzo(a)pyrene concentrations were corrected with reference to a b lank.
The detection limit (DL) for each species was determined according to US-EPA test methods SW-846 (http://www.ep a.gov/sw 846/pdfs/chap1.pdf). A known quantity of each standard substance was measured seven times, and the DL for each species was three times the standard deviation from the seven tests. When converted to atmospheric concentration, the detection limit for each of PAH species, including BaP, was 0.001 ng/m 3 .

Results and Discussion
During study period of 2011, in the months of February to April the Air Quality of peenya was monitored for the parameters PM 10 , Benzo (a)pyrene. The results are summarized in Table 2 and Table 3 and Figure 1 and Figure  2 represents the graphical variation of the selected parameters for study period February 2011 to April 2011. Variation in concentration of PM 10 taken at eight locations at different date over a period of three months at Peenya industrial area. Fro m the above period, the mean concentration of PM10 ranges between a maximu m of 130.22 µg/ m 3 and a minimu m of 100.32 µg/ m 3 which exceeds the permissible limit of 100 µg/ m 3 . Meteorological parameters played a vital ro le in dispersion of PM 10 in atmosphere in the month of April. The PM10 exceeds the permissible standard of NAAQS in all eight locations. This is because of lot of industrial activ ity and more traffic vo lu me is responsible for the increment of PM 10 value. The variation in concentration of Benzo(a)pyrene taken at eight locations at different date over a period of three months at Peenya industrial area. Du ring study period it was observed Benzo(a)pyrene ranged from BDL to 0.0490 ng/m3,in the month of February Kongovi electroplating location has higher concentration compare to the other locations.
The concentration of B(a)P reduces from February to April in all locations. B(a)P concentration showed a significant seasonal cycle during the study period with greater concentration in the month of February due to metro logical factors, with conditions of low temperature and low irradiat ion. Fro m March to April concentration decreased due metrological factors which were hot in summer and increase in wind speed leads to increase in dispersion and dilution.
In the month of march and April dust storm results in increase of respirable suspended particulate matter but B(a)P adsorbs specially on part icle size less than 10µ which may also responsible for low B(a)P concentration from march 2011 to april 2011. B(a)P levels also showed a seasonal dependence on the greater concentration in month of The main sources of BaP around the measuring sites were mostly influenced by emission fro m different sources such as residential heating, industrial facilit ies and traffic. Generally, BaP concentrations are higher during the winter (heating period, fro m October to March) than during the summer (non-heating period, from April to September) period. Concentrations of BaP depend on sources strength and weather conditions. In Peenya industrial area, coal and wood combustion for do mestic heating were probably major contributors to the higher BaP loading in winter. The lower BaP concentrations in the summer period in Peenya industrial area were likely influenced by higher degrees of atmospheric photo degradation and evaporation. One of the reasons that PAHs are lower during the summer is because semi-volatile PA Hs are present in the gas phase in the summer due to higher temperature, while in the winter amb ient temperatures are much lower. BaP was found to be a relatively unstable compound and it is questionable if it is a good indicator of total PAHs or carcinogenic PAHs [12].

Conclusions
The concentration of Ben zo(a)pyrene varies in the ranges BDL to 0.0490 µg/ m 3 which is less then permissible limit o f 1 µg/ m 3 .The Benzo(a)pyrene concentrations at all the eight sampling locations were belo w the permissible standards of Nat ional A mb ient Air Quality Standards (NAAQS). In general, increasing / decreasing / defined trends in the concentration of Benzo(a)pyrene studied from February 2011 to April 2011 has been observed and this trend is attributed to meteorological conditions which might have resulted in dispersion/diffusion Benzo(a)pyrene concentration in the ambient air was found to be within the permissible limit. Part iculate matter 10 (PM 10 ) concentrations exceeding the acceptable limit was observed in the amb ient air during February 2011 to April 2011 (130.22 µg/ m3).
The Peenya Industrial Area, in all the eight locations, PM 10 pollutant exceeds the permissible standards. The presence of high concentration particulate pollutants has a significant negative impact on the amb ient air of study area.