DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBONS IN SOIL AT AL-NAHRAWAN BRICKS FACTORY Thamera K. M. Al-Rudaini 1 and Israa M.H.

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Pak. J. Biotechnol. VOL. 15 (2) 445-450 (2018) ISSN Print: 1812-1837 ww.pjbt.org ISSN online: 2312-7791 DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBONS IN SOIL AT AL-NAHRAWAN BRICKS FACTORY Thamera K. M. Al-Rudaini 1 and Israa M.H. Almousawi 2 1 Ministry of Science and Technology, Baghdad, Iraq. 2 Department of Chemistry, College of Science, University of Baghdad, Baghdad, Iraq. E. mail: 2 israa_mousawi@yahoo.com Article received 8.4.2018, Revised 1.6.2018, Accepted 10.6.2018 ABSTRACT The concentration of sixteen polycyclic aromatic hydrocarbons were determined in soil samples at AL-nahrawan bricks factory. The measured period was two seasons' summer and winter. The soil samples collected from surface and depth chosen site and analyzed by GC apparatus. The most abundant compounds in the summer season were naphthalene, acenaphthene, fluorene, pyrene and benzo [a] anthracene, while in the winter were naphthalene, acenaphthene, fluorine, benzo [k] fluoranthene, benzo [a] pyrene. The concentrations of 16 PAH in the summer were higher than in the winter season. Key word: AL-nahrawan bricks factory, PAHs, GC analysis. 1- INTRODUCTION They are many pollutants in the environmental according to the developments in the many sides of the life especially in industry side, when used oil, black oil, coal and other fuels. Pollution includes air, water and soil. Soil pollution one of the dangerous pollution in the world because effect on the organisms. There are many pollutants in the environment one of them was polycyclic aromatic hydrocarbon. Polycyclic aromatic hydrocarbons (PAHs) are organic compounds consist of two or more fused benzene rings. PAHs as pure chemicals are white or yellowish crystalline compounds. These compounds belong to group of the most dangerous pollutants occurring in environment due to anthropogenic activity. Their origin is connected with combustion of fossil fuels and organic matter, mining and ore processing as the group of the most important sources of PAHs (Khan and Ghouri 2011; Hawthorne and Kreitinger 2006, Robinson et al., 2008). The United States Environmental Protection Agency (USEPA) has included sixteen PAHs in a list of priority pollutants as shown in figure 1. Figure 1: Structures of 16 PAHs. This work includes collocation of soil samples from AL-nahrawan bricks factory at Baghdad city for two seasons. Sixteen polycyclic aromatic hydrocarbons concentrations were determined in surface and depth soil at the chosen site for summer and winter seasons. Soil samples were analyzed by GC apparatus. 2- MATERIALS AND METHODS 2.1 Chemicals and Standard Materials: Chemicals, solvents and apparatus which were used in

446 T.K.M. Al-Rudaini and I.M.H. Almousawi Pak J. Biotechnol. the experimental methods as shows in table 1 and 2. Table 1: Chemical materials and solvents. Substance Specification Origin Activity Acetone Liquid BDH, England Solvent C3H6O 99% Hexane Liquid,C6H14 BDH, England Solvent Methanol Liquid,CH3OH Riedl De Haen AG Solvent 16 PAHs Solids PAH Research Used in GC calibration curves Standards Institute, Germany Table 2: Apparatus and accessories. Instrument Specification Origin Activity Hand Shovel - Local Remove soil from surface Soxhlet Micro filter Gas Chromatography (FID detector) 250 ml round-bottom flask, 50 ml extractor Halalab Extraction of PAHs from soil samples Syringe filter pore size Hangzhou a Filtration for GC analysis 0.2 µm now Co.LTD Agilent Germany Estimation the PAHs in soil samples 2.4 Standard Solution: Retention times for standard individual sixteen of polycyclic aromatic hydrocarbons were measured in the GC apparatus. Stock solution was prepared by dissolving every PAH compound in methanol. These solutions were used for GC calibration curve with concentrations range (3-13) ppm. 2.5 GC analysis: The twelve soil samples were analyzed by GC apparatus to determine the concentration of sixteen PAHs compounds (Lau et al., 2010, Obint et al., 2013). Detector temperature was kept at 280 C. The transfer line and ion source temperature was 90 0 C (hold for 1 min) to 150 0 C (10 0 C/min) then ramped to 300 0 C (5 0 C/ min) and final temperature was 300 0 C (5 0 C/ min, hold for 12 min). The analysis time for every sample was 50 minutes. 2.2 Description of sampling sites: Sampling site selection is an important step in environmental pollution studies. Sampling sites were chosen near the source of emission of pollutants and around it to measure the PAHs. AL-nahrawan bricks factory were collection consists of about 300 production units. It located in south-east of Baghdad as shown in figure 2. The height of chimney is about 40 m and the used fuel is black oil. 2.3 Sampling and sample extraction: The surface soil samples were collected using hand shovel and measuring tape, as well as mechanical shovel in AL-nahrawan bricks factory site. The monitoring of PAHs was focused on the surface soil and a depth 30 cm of sediment surface for chosen site. Twelve soil samples were collected during summer and winter seasons from January to august 2017. Figure (2): AL-nahrawan bricks factory A 20 gm from soil sample was dried for four hours at 60 o C and grinded. Ground soil was put into the soxhlet apparatus using two solvent acetone and hexane (1:1) for about 15 hours. (Khan et al., 2005, Haleyuretal et al., 2016, Dong et al., 2012) After extraction, the extract was removed from the soxhlet apparatus and filtered

Vol. 15 (2) 2018 Determination of poly aromatic. 447 through filter paper. The solvents were removed to dryness using a rotary evaporator (Yamato RE 510) at 60 o C under gentle vacuum. The dried samples were dissolved in 5 ml methanol and filtered using micro filter. The solution was kept in glass container at low temperature before analysis. 3-RESULTS AND DISCUSSION The retention time of standard individual policyclic aromatic hydrocarbons was measured according to the temperature programmer's (paragraph (2.5)) and calculated the linearity equation for every compound as shown in table 3. Table 3: GC summary results of retention time and linearity equation. No. PAHs Retention time min. Equation of a straight line Ŷ = ac +b 1 Naphthalene 6.457 0.444 c -0.267 2 Acenaphthylene 10.377 0.276 c 0.198 3 Acenaphthene 10.979 0.191 c -0.149 4 Fluorene 12.740 0.25 c -0.55 5 Anthracene 15.161 1.954 c - 2.018 6 Phenanthrene 16.449 2.236 c- 6.879 7 Fluoranthene 21.502 0.732 c + 0.289 8 Pyrene 22.422 1.236 c - 1.379 9 Benzo(a) Anthracene 27.878 5.554 c -11.331 10 Chrysene 32.545 0.306 c 1.542 11 Benzo(b) Fluoranthene 32.463 3.344 c -4.029 12 Benzo(k) Fluoranthene 33.445 0.650 c 0.274 13 Benzo(a) Pyrene 33.665 0.757 c - 2.486 14 Indeno(1,2,3-cd) Pyrene 35.224 1.071 c + 0.096 15 Dibenzo(a,h) anthracene 36.894 0.147 c -1.039 16 Benzo(g,h,i) Perylene 37.684 0.133 c 1.34 Figure 3: Calibration curve of standard anthracene compound. Figure 4: Calibration curve of standard pyrene compound.

448 T.K.M. Al-Rudaini and I.M.H. Almousawi Pak J. Biotechnol. The mean concentrations of polycyclic aromatic hydrocarbon compounds in soil samples were calculated by linearity equation after comparison with the retention time of standard compound for summer and winter seasons as shown in tables 4 and 5. Table 4: Mean concentration of the individual PAH (µg/gm) measured in summer at AL-nahrawan bricks factory using GC analysis. Surface soil Depth soil Compound Mean ± Confidence interval * Mean ± Confidence interval Naphthalene 195.078 ± 0.195 2.038 ±0.094 Acenaphthylene ND ND Acenaphthene 14.371 ± 0.615 5.081 ± 0.076 Fluorene 15.475 ± 0.089 6.793 ± 0.204 Phenanthrene 2.315 ± 0.195 1.424 ± 0.256 Anthracene 1.958 ± 0.129 1.141 ± 0.046 Fluoranthene ND ND Pyrene 10.84 ± 0.179 15.452 ± 0.153 Benzo[a]anthracene 3.255 ± 0.359 4.012 ± 0.002 Chrysene ND ND Benzo[b]fluoranthene 1.713 ± 0.219 1.424 ± 0.061 Benzo[k]fluoranthene ND 1.288 ± 0.186 Benzo[a]pyrene ND 1.855 ± 0.111 Indeno[1,2,3-cd]pyrene ND ND Dibenz[a,h]anthracene ND ND Benzo[ghi]perylene ND ND Mean (X ) when n=3 (µg /mg), confidence interval = t σ n 1 3, degree of freedom (df) =2 and ttable=4.303 for n=3 (No. of measurements). ND: not detected Table 5: Mean concentration of the individual PAH (µg/gm) measured in winter at AL-nahrawan bricks factory using GC analysis. Surface soil Depth soil Compound Mean ± Confidence interval Mean ± Confidence interval Naphthalene 12.069 ± 0.144 32.713±0.031 Acenaphthylene ND ND Acenaphthene 9.484 ±1.092 7.484±0.125 Fluorene 7.515±0.745 2.831 ±0.165 Phenanthrene ND 2.608 ±0.161 Anthracene 1.139±0.098 3.052 ± 0.124 Fluoranthene ND ND Pyrene ND ND Benzo[a]anthracene 2.445± 0.112 1.702± 0.032 Chrysene ND ND Benzo[b]fluoranthene 1.725±0.060 3.575± 0.063 Benzo[k]fluoranthene 18.843± 0.047 ND Benzo[a]pyrene 11.69±0.199 ND Indeno[1,2,3-cd]pyrene ND ND Dibenz[a,h]anthracene ND ND Benzo[ghi]perylene ND ND The results show that sixteen polycyclic aromatic hydrocarbons were spread at chosen location as shown in figures 5 and 6. The concentration of 16 PAHs were varied in the two seasons. The most abundant compound in the summer season were naphthalene, acenaphthene, fluorene, pyrene and benzo[a]anthracene while in the winter were naphthalene, acenaphthene, fluorine, benzo [k] fluoranthene, benzo[a]pyrene due to these compounds had higher environmen-

Vol. 15 (2) 2018 Determination of poly aromatic. 449 tal stability because they have high aromatic property (Hassan et al., 2013; Schleyer et al., 2001; Dewar, 1969). The high concentration was naphthalene 195.078 (µg/gm) due to naphthalene was easily formed according to the mechanism (March 1992; Hess et al., 1971). The high concentration in the winter was benzo[k]fluoranthene 18.843 (µg/gm). The existence of some polycyclic aromatic compounds at AL-nahrawan bricks factory due to incomplete combustion of black oil as well as effect of metro- rological conditions at chosen site. The cli-mate in Iraq is hot, dusty in summer and cool dry in the winter. The most effect of precipitated of PAHs on the soil were humidity and dust because PAHs deposition on the particles suspended in atmosphere (Rajput and Lakhani, 2009, Aryal et al., 2005). The concentration of PAHs in summer higher than in winter as a result of requests the production of bricks leading to consumption more fuel and more emission of PAHs in the summer. Figure 5: Mean concentrations of individual PAH in summer at AL-nahrawan bricks factory. Figure 6: Mean concentrations of individual PAH in winter at AL-nahrawan bricks factory.

450 T.K.M. Al-Rudaini and I.M.H. Almousawi Pak J. Biotechnol. Conclusion Sixteen polycyclic aromatic hydrocarbons were determined in soil samples at AL-nahrawan bricks factory by used GC apparatus. The concentration varied in the surface and depth soil as well as in the summer and winter seasons. The most polycyclic aromatic hydrocarbons speared were low molecular weight. The most abundant compound in the summer season was naphthalene. REFERENCES Aryal, R.K., Furumai, H., Nakajima, F. and Boller, M., Dynamic behavior of fractional suspended solids and particle-bound polycyclic aromatic hydrocarbons in highway runoff. Water Research, 39(20):5126-5134 (2005). Dewar, M.J.S., Molecular orbital theory of organic chemistry (1969). Dong, C.D., Chen, C.F. and Chen, C.W., Determination of polycyclic aromatic hydrocarbons in industrial harbor sediments by GC-MS. International journal of environmental research and public health, 9(6): 2175-2188 (2012). Haleyur, N., Shahsavari, E., Mansur, A.A., Koshlaf, E., Morrison, P.D., Osborn, A.M. and Ball, A.S., Comparison of rapid solvent extraction systems for the GC MS/MS characterization of polycyclic aromatic hydrocarbons in aged, contaminated soil. MethodsX, 3:364-370 (2016). Hassan, Y., Characterization of road side surface soil and road runoff water of Guwahati city with special emphasis on heavy metals (2014). Hawthorne, S.B., Miller, D.J. and Kreitinger, J.P., Measurement of total polycyclic aromatic hydrocarbon concentrations in sediments and toxic units used for estimating risk to benthic invertebrates at manufactured gas plant sites. Environmental toxicology and chemistry, 25(1) :287-296 (2006). Hess Jr, B.A. and Schaad, L.J., Hueckel molecular orbital. pi. resonance energies. New approach. Journal of the American Chemical Society 93(2): 305-310 (1971). Khan, M. and Ghouri, A.M., Environmental pollution: its effects on life and its remedies (2011). Khan, Z., Troquet, J. and Vachelard, C., Sample preparation and analytical techniques for determination of polyaromatic hydrocarbons in soils. International Journal of Environmental Science & Technology 2(3): 275-286 (2005). Lau, E.V., Gan, S. and Ng, H.K., Extraction techniques for polycyclic aromatic hydrocarbons in soils. International journal of analytical chemistry, (2010). March, J., Advanced organic chemistry: reactions, mechanisms, and structure. John Wiley & Sons, (1992). Michigan, USA. Environmental toxicology and chemistry, 27(2) :313-322 (2008). Obini, U., Okafor, C.O. and J.N. Afiukwa, Determination of levels of polycyclic aromatic hydrocarbons in soil contaminated with spent motor Engine oil in Abakaliki Auto-Mechanic Village. Journal of Applied Sciences and Environmental Management 17(2):169-175 (2013) Rajput, N. and Lakhani, A., Particle associated polycyclic aromatic hydrocarbons in urban air of Agra. Indian J. of Radio & Space Physics, 38: 98-104 (2009). Robinson, S.D., Landrum, P.F., Van Hoof, P.L. and Eadie, B.J., Seasonal variation of polychlorinated biphenyl congeners in surficial sediment, trapped settling material, and suspended particulate material in Lake Schleyer, P.V.R., Manoharan, M., Jiao, H. and F. Stahl, The acenes: is there a relationship between aromatic stabilization and reactivety?. Organic letters 3(23): 3643-3646 (2001).