PB85-169597 PAH (Polycyclic Aromatic Hydrocarbons) Uptake by Plants: Methodology and Initial Investigations Clemson Univ., SC Prepared for Environmental Research Lab., Athens, GA Feb 85 I ------- EPA/600/D-85/036 February 1985 PAH UPTAKE BY PLANTS Methodology and Initial Investigations by John Coatesl, Alan W. Elzermanl, and A. Wayne tidirlson? Environmental Systems Engineering Clemson University Clemson, SC 29631 ^Environmental Research Laboratory U.S. Environmental Protection Agency Athens, GA 30613 ENVIRONMENTAL RtSfcARCH LABORATORY OFFICt OK RESEARCH AND DEVELOPMENT U.S. ENVIRONMENTAL PROTECTION AGENCY ATHENS, (iA 30613 ------- NOTICE This document has been reviewed in accordance with U.S. Environmental Protection Agency policy and approved for publication. Mention of trade naaes or coaaercial products does not constitute endorse- ment or recoMendation for use. ii ------- PAH UPTAKE BY PUNTS; METHODOLOGY AND INITIAL INVESTIGATIONS JOHN COATESi, ALAN W. ELZERMANl, A. WAYNE GARRISON2 (1 Environmental Systems Engineering, Clemson University, Clemson, SC 29631; (2)Environmental Research Laboratory, U.S. EPA, Athens, OA 30613. . INTRODUCTION Polycycl1c aromatic hydrocarbons (PAKs) are formed during the pyrolysis of naturally occurring organic materials. Pyrolytic reactions may be induced anthropogenlcally or by natural events (e.g., forest and grassland fires or volcanic activity). Background levels and the ublgultous occurrence of PAHs in the environment may result from synthesis 1n terrestrial vegetation, microbial systhesls and volcanic activity (Andelman and Suess, 1970; Suess, 1976; Shabad, 1980). The greatest amounts of PAHs released Into the environ- ment, however, come from anthropogenic sources (Andelman and Suess, 1970). Fossil fuel burning for power production appears to be the most significant source, with motor vehicle fuel combustion and anthropogenic forest and agricultural fires contributing an additional IX and 81 of the total, respectively (Suess, 1976). Recent reviews by Howard and Fazio (1980) and Edwards (1983) provide summaries addressing the sources, occurrence, plant uptake, degradation and analyti- cal methodologies for PAHs 1n the environment. Although a large data base has accumulated on the presence of PAHs in food products and plants, routine measurement of the uptake and accumulation of PAHs 1n vegetation has been hampered by analytical techniques. Sensitivity Is often a problem with these techniques and the majority of the proce- dures cited in the literature are tedious, length/ and expen- sive to perform and fheiefore are not amenable to routine analyses. For example, Winkler et al_. (1977) described a method for the determination of TOHs with three to seven rings In wet and dry maize. Samples were extracted using a Soxhlet apparatus; extracts were rotary evaporated, saponified, filtered over silica gel, evaporated for a second tipe and partitioned with Sephadex LH 20. Howard et al_. (1968) described a method of similar complexity for root vegetables using saponification, multiple solvent partitioning, solvent replace- ment, and adsorption chromatography on FloMsil. Recently, Coates et aK (1984) have reported a simpler method suitable for routine analysis of PAHs 1n plant tissues with sufficient sensitivity for screening PAH uptake by plants growing under conditions of low to moderate exposure to PAH contamination, 1 ------- PAHs IN PLANTS Such as might occur next to a roadway, upon Irrigation with treated wastewater, or during overland Mow treatment of wastewater. As reviewed brlow, the sonlflcatlon extraction procedure coupled to a silicic acid clean-up scheme was found to be reliable and convenient. The new sonlflcatlon method of Coates et al. (1984) was applied In a field study of plants 1 rrlgateT~wTTh PAH- spiked domestic wastewater or grown on contaminated soil. The method was found appropriate to measure concentrations In hybrid grain sorghum and fescue down to the 25 ugAg level. Apparent uptake of some PAHs from contaminated soil and/or Irrigation water was demonstrated using this technique. MATERIALS ANO METHOOS Chemicals (a) Acetonltri1e and pentane (pesticide grade) b) Sodium sulfate (anhydrous granular, ACS quality) c) Sodium chloride (granular, ACS quality) (d) Mercuric chloride (granular, ACa quality) (e) Silicic acid (Unlsi 1R activated silicic acid, 100- 200 mesh, CI arkson Chemical Co., Inc.) (f) PAHs (Aldrlch Chemical Co.) Acenaphthylene, 95X Flouranthene, 98% Pvrene, 99+% Bemo[a]Pyrer.e, 98% Benzo[g,h,1]Perylene, M.P. 277-279°C (g) PAH standards (National Bureau of Standards SRM 1647, 16 PAHs In acetonltrlle) (h) Laboratory blank water (twice distilled In glass) Apparatus (a) Sample preparation (HobartR food processor Model 8181 D) (b) Sonlflcatlon extraction (Brlnkman PolytronR with PT-20 ST probe generator) (c) Centrifuge (Sorvall Superspeed RC-2B automatic, refrigerated, with GSA heat) (d) Sample concentration (Kuderna-Oanlsh concentrator, 500 ml) (e) Sample clean-up columns (Pasteur plpets) (f) Gas-liquid chromatography (Hewlett-Packard Model 5880 Capillary GC equipped with an FID detector and 2 ------- PAHs IN PLANTS a 30M x 0.2Iran 10 SE-54 capillary col win having a 0.25-i«i film thickness). Instrument conditions: linear velocity, )3 cm/sec; Injector temperature, 250°C; detector temperature, 350°C; temperature program, 70°C for 2 minutes then 20*C/m1n to 125°C then 4°C/m1n to 290#C, held for 15 minutes. Plant Extraction Cleanup Technique As reported by Coates et aK (1984), acetonltrlle (75 mL) was added to the centrifuge tube containing the plant mulch. The sonlflcation probe generator was Immersed Into the suspen- sion tube and the mixture sonicated for 2 minutes at maxlmun speed. Contents wsre then centrlfuged at 5500 g for 20 minutes and the centrlfugate quantitatively transferred to a 500 mL separator? funnel. The solid was washed with 25 mL of acetonltrlle and centrlfuged; t*e centrlfugate was combined with the first extract. Pent' (50 mL) was added to the separator? funnel containing t oetonltrlle and shaken vigorously for 2 minutes. Water & iturated with sodium chloride (10 mL) was then added to the separator? funnel, followed by 350 mL of laboratory blank water, and again shaken for 30-40 seconds. The 1mr?s1sc1ble phases were separated, and the pentane layer was dried by passing through a sodium sulfate column and drained Into a 5C0-mL K-D apparatus. The pentane extract «s concentrated to a volume of 3 to 4 mL 1n a water bath at 65°C, removed, and allowed to cool for 10 minutes. The K-D flask was rinsed with 3 mL of dry pentane and the 10-mL concentrator tube was removed from the flask. All ground glass joints were rinsed with 2 mL of pe.itane, which also was collected 1n the concentrator tube. The extract was then blown down to 0.5 mL with dry nitrogen at room temperature and quantitatively transferred to a prewashed micro clean-up column containing 1.5 gm of Un1s11 silicic acid; the column was then eluted with 5 mL of dry pentane to remove primarily aliphatic hydrocarbons *-orn the extract. The second and third 5-mL fractions were ch eluted with a 85:15 solvent mixture of pentane and methylene chloride (DCM). All fractions were again concentrated to 0.5hhL with dry nitrogen and analyzed by GC-FIO. All PAHs appeared 1n the second 5-mL fraction collected. No PAH* were ever found in the first (pentane) fraction nor the third (pentane:DCM) fraction. The clean-up proceduih was sufficient for extracting up to 15 gm of air dried plant material; additional silicic acid was required to remove Interfering polar constituents when extracting more than 15 gms of plant 3 ------- PAHs IN PLANTS material. The method Mas scaled up when necessary on the basis of silicic acid pore volume to plant mass ratios. Sam)le Collection and Spiking for Recovery Studies Immature hybrid grain sorghum Mas harvested from the Clemson University Agricultural Experiment Station - Simpson Farm diving the early fall of 1982 and stored at -I0°C until recovery studies Mere Initiated. All plants Mere removed from storage and the aerial plant parts homogenized 1n a food processor prior to spiking for recovery studies. A weighed portion (2*10 gm) of plant mule*". was placed In a 150-fliL glass centrifuge tube with I ml of a PAH mixed standard (NBS SRM 1647). Laboratory blank water (150 mL) and 1 rr.L of 185 inmolar mercuric chloride as a bactericide were added to the tti>e. The tube was capped and placed on a slide shaker 1n a dark room for 24 hours. After shaking, the contents were centrlfuged at 5500 g for 20 minutes. The aqueous phase was transferred to a separatory funnel and extracted 3 times w4th 30-mL portions of pentane. Extracts were combined and concentrated using a K-0 apparatus to approximately 3 to 4 mL, then by dry nitrogen to 0.5 mL. The centrifuge tube wall was extracted 3 times with 10-mL portions of pentane and concentrated to 0.5 m*. above. The plant residue was extracted by sonlflcatlo.. Experimental Design for Field Study. A field study was originally Initiated (Coates et al.. 1964) to demonstrate that the sonlflcatlon technique was suitable to extract plant tissue that had accumulated PAHs during growth as well as with spiked samples. The additional data reported here were obtained to make an Initial assessment or uptake of selected PAHs and to Investigate whether uptake ' could occur from contaminated soil as well as from Irrigation water. In the Irrigation water study, hybrid grain sorghum and fescue were grown from seed In 20-L containers and Irrigated dally with PAH-spiked municipal sewage effluent for an 8-weyk period during the simmer of 1983. Treated activated sludge effluent wastewater was obtained from the Coneross Wasto Treatment Plant, Oconee County, South Carolina, and stored with aeration at 4°C during the study period. The ? xpsr Intents 1 design was a completely -ando.n design with triplicate controls and triplicate PAH treatment representing two levels of PAH contamination for both sorghum and fescue. Polycycllc aromatic 4 ------- PAHs IN PLANTS hydrocarbons used In this 'nvestlgatlon Mere acenaphthylene, fluoranthene, pyrene, benzo[a]pyrene, and benzo[g,h,1]perylene. The concentration of the five PAHs In the spiked wastewater and the total mass of PAHs Introduced to the growing plants during the study period are listed in Table 1. TABLE i CONCENTRATIONS AND MASSES OF PAHs USED IN THE IRRIGATION STUDY PAH Concentration 1n Spiked Wastewater Total Mass Applled In Spiked Waste- water to Each Container Treatment 1 2 ug/L Treatment 1 2 u9 Acenaphthylene 2.0 1000 640 320,000 F1 uoranthene 2.0 200 640 64,000 Pyrene 1.0 100 320 32,000 Benzo[a]pyrene 0.05 1.0 16 320 Benzo[g,h,1jperyl ene 0.10 0.5 32 160 plants were irrigated using hand-pump pressurized spray cans. Containers were moved frequently to eliminate position In the growing area as a variable. The aerial part of each plant was harvested at the end of the growing period and frozen until extracted. The seeds were planted 1n July, Irrigation with spiked wastewater was begun 1n September, and the plants were harvested In November. To obtain some Indication of the -«o*»nt1al for root uptake of PAHs, the soil In two 20-L to liners was contami- nated with three PAHs (acenaphthylene, f.joranthene and pyrene). One gram of each PAH was added to the top two Inches of soil and thoroughly mixed. The soil density was estimated to be 1.25 gm/cm3, which translated Into a calculated 217 ppm PAH concentration In soil (not verified by extraction). 5 ------- PAHs IN PLANTS Contaminated soil was incubated for 1 month prior to seeding. Fescue Mas planted 1n one container and hybrid grain sorghum was planted 1n the second container. Two controls wr.re planted at the same time and all four containers wert frr1gat°d wit* tapwater during the 8-week growing period. During this tirce the soil surf* ; was not allowed to dry, thus reducing the effect of "dust.ng," which could contaminate aerial plant parts. Evaluation of Analytical Technique As reported by Coates et ai_. (1964), the elutlon ¦ .n . and corresponding relative retention times for the 16 • s present In the N6S SRM 1647 standard are lasted in Table 2. The chromatographic conditions used 1n this Investigation are listed 1n the Materials and Methods section. Retention orders for PAHs having different molecular weights were verified using gas chromatography on an SE-54 capillary column and selected 1on monitoring mass spectrometry (GC-MS). The retention order for the remaining PAH molecular weight pairs (phenanthrene-anthracene, fluoranthene-pyrene, chrysene-B[a]A, and B[b]F-B[k]F) were determined by spiking the NBS standard with an EPA quality control sample containing one of the PAHs of the paired combinations and analyzing by the GC-MS technique. RETENTION TIMES FOR 16 PAHs PRESENT IN THE NBS SRM 1647 STANDARD* RESULTS ANO DISCUSSION TABLE 2 PAH Relative Retention Mol. Wt. (referenced to Pyrene) 1. Naphthalene 2. Acenaphthylene 3. Acenaphthene 4. Fluorene 5. Phenanthrene 6. Anthracene 128.2 152.2 154.2 166.2 178.2 178.2 0.272 0.457 0.485 0.566 0.733 0.741 6 ------- PAHs IN PLANTS TABLE 2 (Continued) PAH Relative Retention Mol. Wt. (referenced to Pyrene) 7. Fluoranthene 8. Pyrene 9. Benzo[a]anthracene 10. Chrysene 11. Benzo[b]fluoranthene 12. Benzofluoranthene 13. Benzopyrene 14. Indeno[l,2,3-cd]pyrene 15. D[a,h]anthracene 16. BenzoCg.hJ ]perylene 202.3 202.3 228.3 228.3 252.3 252.3 252.0 276.3 278.4 276.3 0.959 1.000 1.238 1.246 1,439 1.443 1.494 1.739 1.749 1.805 ~After Coates et al., 1984 Plant extracts when concentrated typically contain high percentages of polar organic compound* that co-elute and significantly Interfere with many chromatographic analyses. Many of the available clean-up schemes are complex and tedious to Implement for routine analyses. The single sorbent clean-up scheme used by Coates et aj_. (1984) coupled with solvent partitioning was sufficient to allow quantification of all PAHs listed in Table 2 at the 25 yg/kg level. PAHs extracted by acwtonltrile were partitioned Into pentane, dried on sodium sulfate, concentrated to 0.5 mL and cleaned up with a micro-silicic acid column, as noted In the Materials and Methods Section. Two 5huL fractions were eluted with a pentane:DCM (85:15) solvent mixture. Optimization of the solvent ratio was necessary to maintain the usefulness of the single adsorbent clean-up step (Coates et al_., 1984). Figure la Is a chromatogram of the PAH standard and figure lb 1s a chromatogran of the first 5-ml eluant fraction of a plant extract using pentane:DCM (85:15) as eluant. Coates et al. (1984) showed quantitative recovery for most of the PAHs"from hybrid grain sorghum extracts for the concentra- tion and cleanup steps with the exception of 1ndeno[l,2,3-cd] pyrene and benzo[g,h,1]perylene, which showed losses of 12 and 17 percent, respectively. 7 ------- P/ ..IN PUNTS (a) J L U it u is I j.*. i (b) „]JL-L FIGURE 1. Chromatograra of (a) NES 1647 standard (numbered peaks appear 1n order as In Table II) and (b) sample eluted with 85:15 pentanerDCM. Overall method calibration and recovery also was evaluated (Coates et al., 1984). Initial calibration studies for the 16 PAHs use? Tn this Investigation Indicated detector !1near1ty over the analytical working range so a single point calibration curve was used to quantify PAH concentration and calculate recovery efficiencies. Standards (NBS SRM 1647) were injected in the gas chromatograph every 4 to 5 samples to monitor system drift. Results of overall method recovery studies are listed in Table 3. These data were corrected for residual naphthalene, acenaphthylene and acenaphthene concen- trations remaining 1n the aqueous phase after spiking and Incubation with the plant mulch. Aqueous phase concentrations of the remaining PAHs ware below detectable limits (C.05-1 8 ------- PAHs IN PLANTS ng/ml). See Materials and Methods for spiking details. Concentrations of PAHs spiked Into the plant tissue homogenates were between 600 and 4500 ug/kg. TABLE 3 OVERALL METHOD RECOVERY EFFICIENCIES (PAH PLANT CONCENTRATION MO-WOO *A«1 PAH Mass 1n Spike Percent Recovered* % 1. Naphthalene 22.5 2. Acenaphthylene 13.1 3. Acenaphthene 21.0 4. Fluorene 4.92 5. Phenanthrene 5.06 6. Anthracene 3.29 7. Fluoranthene 10.1 8. Pyrene 9.84 9. B[a]A 5.03 10. Chrysene 4.68 11. B[b]r 5.11 12. B[k]F 5.02 13. B[a]P 5.30 14. I[l,2,3-cd]P 4.06 15. D[a,h]A 3.68 16. B[g,h,1]Perylene 4.01 47*5 n 81*(8) 80+(8) 8Z+(8) 90+(9 82?(8 83+12 837(13 72+(6 717(9 62+16 617(15 57+(5) 49+(17) 45+(17 617(14 •Average of four replicates with standard deviations in parentheses. Data 1n Table 3 suggest that the son1f1cat1on procedure was generally efficient 1n removing most of the PAHs from the plant matrix. Recovery efficient as, however, for the more volatile naphthalene and for a few of the more hydrophobic PAHs were lower (45-62%). The practical detection limit was approximately C.025 u9/9* 9 ------- PAHs IN PLANTS Field Application Studies Irrigation Study. At the end of the 8-week growing period, the hybrid grain sorghum and fescue that were Irrigated with PAH-sp1ked domestic wastewater Were harvested and stored frozen until extracted. All plants were extracted using the son1f1cat1on technique with the clean-up scheme outlined above, and extracts were analyzed by GC-FID. Results are listed 1n Tables 4 and 5 for hybrid grain sorghum and fescue, respectively. Concentrations for each plant type are 1n units of microgram PAH per gram of air dried plant extracted. Error estimates for the data presented 1n Table 4 were not available because replicates for both control and treatments 1 and 2 had to be combined to have enough plant material to extract. Error estimates for the control and the two treatment levels for the fescue uptake study were calculated and were used 1n significance analysis. TABLE 4 PAH CONCENTRATIONS IN HYBRID GRAIN SORGHUM IRRIGATED WITH PAH-SHkEB DOMESTIC WASTEWATER PAH Control vg/g Treatment 1 m9/9 Treatment 2 ug/g Acenaphthylene ND* ND ND Fluoranthene 0.05 0.82 1.32 Pyrene 0.02 0.49 0.63 Benzo(a)pyrene ND ND ND Benzo(g,h,1)perylene ND ND ND *ND means not detected (less than approximately 0.02 yg/g). 10 ------- PAHs IN PLANTS TABLE 5 PAH CONCENTRATIONS IN FESCUE IRRIGATED WITH PAH-SPIKED PflHESTlC WASTEWKTEE PAH Control Treatment Treatment 1 2 (avg. _+ standard deviation) Acenaphthylene ND* ND 0.58+0.16 Fluoranthene 0.12+0.03 0.20+0.07 50+13 Pyrene 0.07+0.03 0.10+0.04 24+6 Benzo(a)pyrene KD" TlD TiD Benzo(g,h,1)perylene ND ND 0.13+0.03 *ND means not detected (less than approximately 0.025 wg/g). Fluoranthene and pyrene were found 1n the sorghum at concentrations significantly greater than the control. Four of the five PAHs were present 1n trie fescue Irrigated with spiked wastewater at concentrations greater than 1n the controls. Concentration differences between treatment 1 and treatment 2 and the controls were significant at the <0.01 level as determined by the Student's T test. Table 1 gives the total mass of each PAH applies to the plants for each treatment through the spiked Irrigation water. No attempt was made to account for losses of PAHs due to sorption, blodegradatlon, photolysis, volatilization from soil surface or transpiration, but only to determine whether measureable quantities of PAHs could be found associated with growing plants Irrigated with PAH contaminated wastewater. Similarly, although the experiment Indicated uptake by the plants, 1t does not distinguish between foliar or root uptake or a combination of the two. As expected, given different physical and chemical characteristics, some PAHs accumulated more than others. Further work 1s required to elucidate mecha- nisms of uptake and accumulation, however. 11 ------- PAHs IN PLANTS Contaminated Soil Study Results are listed In Tables 6_and 7 for hybrid grain sorghum and fescue and Indicate the magnitude of plant uptake for the PAHs used 1n this study. It 1s Important to note that treatments were not replicated and the nunbers should only be viewed as Indications of potential accumulation. No attempt was made to correlate uptake or accumulation as a function of plant growth. The data strongly suggest, however, that some PAHs may be taken up by plant roots and translocated to the aerial plant. Two of the three PAHs studied, acenaphthylene and fluoranthene, exhibit greater aqueous solubilities and lower hydrophobic character than pyrene and were found at higher levels 1n the plant tissue than pyrene 1n the contami- nated soil study. In addition, acenaphthylene was the most volatile of the PAHs studied and may have been lost from the system. If the results presented are order of magnitude indicators of plant accumulation tendencies, they are consis- tent with the above characteristics of PAHs and Indicate lower uptake of PAHs with lower aqueous phase concentrations. TABLE 6 PAH CONCENTRATIONS IN SORGHUM GROWN ON CONTAMINATED SOIL PAH - Control Contaminated Soil wg/y wg/g Acenaphthylene ND* NO Fluoranthene 5.23 73.49 Pyrene NO 2.38 *ND means not detected (approximately less than 0.02 ug/g) 12 ------- PAHs IN PLANTS TABLE 7 PAH CONCENTRATION IN FESCUE GROWN ON CONTAMINATED SOIL PAH Control Contaminated Soil vg/g v9/9 Acenaphthylene ND* 3.09 F1uoranthene 0.13 10.32 Pyrene 0.06 3.29 *NU means not detected (approximately less than 0.02 yg/g) Further work 1s required to elucidate and verify uptake mechanisms and to determine the Impact of application rates and methods, volatilization, photodegradatlon, blodegradatlon, plant metabolism and translocation as possible explanations for the ranges of PAH concentrations observed 1n aerial plant parts. ACKNOWLEDGEMENTS This work was supported primarily by a cooperative agreement to Environmental Systems Engineering, Clemson University from the U.S. Environmental Protection Agency through the Athens Environmental Research Laboratory, for which appreciation 1s expressed. Partial support through NSF grant No. ISP-8011451, "Environmental Engineering Chemistry" 1s also gratefully acknowledged. Finally, our thanks to Elaine McGarlty and Sherry Jarrard for their excellent work on the manuscript. NOTE: Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the United States Environmental Protection Agency. REFERENCES 1. Andelman, J.B., and Suess, M.J. (1970): Polynuclear aromatic hydrocarbons 1n the water environment, Bui 1. WHO, 43: 479-508. 13 ------- PAHs IN PLANTS 2. Coates, J. T., Elzerman, A. W., and Garrison, A. W. (1984). Analysis of selected PAHs 1n plant tissues. Final Report, Grant No. CR810496, Analytical Techniques for Selected Organlcs In Plant Tissue, Athens Environ- mental Research Lab, US-EPA. ("Manuscript 1n press). 3. Edwards, N.T. (1983): Polycycllc aromatic hydrocarbons (PAHs) In the terrestrial environment - A Review, J. Environ. Qua!., 12: 427-441. 4. Geqer, W. and Schnaffner, C. (1978): Determination of polycyclic aromatic hydrocarbons 1n the environment by glass capillary gas chromatography, Anal. Chem., 50: 243- 249. . . 5. Grimmer, G. and Hlldebrandt, A. (1972): Concentration and estimation of 14 polycycllc aromatic hydrocarbons at low levels In high-protein foods, oils, and fats, J. Assoc. Offlc. Anal. Chem., 55: 631-635. 6. (toward, J.W. and Fazio, T. (1980): Review of polycycllc aromatic hydrocarbons 1n foods, J. Assoc. Offlc. Anal. Chem., 63: 1077-1104. 7. Howard, J.W., Fazio, T., White, R.H., and Kllmeck, B.A. (1968): Extraction and estimation of polycycllc aromatic hydrocarbons In total diet composites. J. Assoc. Offlc. Anal. Chem., 51: 122-129. 8. Kolarovic, L. and Traltler, H. (1982): Determination of polycycllc aromatic hydrocarbons In vegetable oils by caffeine complexatlon and glass capillary gas chromatography, J. Chromatog., 237: 263-272. 9. Schamp, N. and vanWassenhove, F. (1972): Determination of benzo(a)pyrene 1n bitumen and plants, J. Chromatog., 69: 421-425. 10. Shabad, L.M. (1980): Circulation of carcinogenic polycycllc aromatic hydrocarbons 1n the human environment and cancer prevention, J. Natl. Cancer Inst., 64: 405-410. 11. Suess, M.J. (1976): The environmental load and cycle of polycycllc aromatic hydrocarbons, Sc1. Total Environ., 6: 239-250. 12. Winkler, E., Buchele, E., and Mueller, 0. (1977): Method for the determination of polycycllc aromatic hydrocarbons 1n corn by capillary column aas liquid chromatography, J. Chromatog., 138: 151-lb4. 14 ------- TECHNICAL REPORT DATA /Phase rmJ liuiructiont on the rtrrne beforr completingi 1 REPORT NO 7 EPA/600/D-85/036 4. title and Subtitle PAH UPTAKE BY PLANTS: Methodology and Initial Investigations ft. REPORT DATE February 1985 6. PERFORMING ORGANIZATION CODE » 7 AUTHORlS) John T. Coates, Alan W. Elzerman and A. Wayne Garrison1 • PERFORMING ORGANIZATION REPORT NO B PERFORMING OROANIZA HON NAME AND AOORESS Environmental Systems Engineering, Clemson University, CI emson SC 29631 ~Environmental Research Laboratory, U.S. Environmental Protection Agency, Athens GA "'OSIS 10 PROGRAM ELEMENT NO CCUL1A 68-01-2281 12. SPONSORING AGENCY NAME AND ADDRESS U.S. Environmental Protection Agency—Athens GA Office of Research and Development Environmental Research Laborato", *.thens GA 30613 13. TYPE OF REPORT AND PERIOO COVEREO Published paper 14 SPONSORING AGENCY CODE EPA/600/01 19 SUPPLEMENTARY NOTE- Contact: A.W. Garrison, H-2b0-Jl8j IS. ABSTRACT An analytical protocol was developed that allows qiantlf1cat1on of 16 PAHs 1n grain sorghum and fescue grass. Compounds are extracted from the plant stem and foliage by homo&enatlon/sol1cat1on using acetonltrlle as the primary solvent. The extract 1s cleaned up by solvent partitioning Into pentane followed by adsorption chromatography on silicic acid, then analyzed by GC-FID. This method can be used to neasure PAH concentrations at the 25 ug/kg level 1n the plant. 17 Kt* ftORDS ANO DOCUMENT ANALYSIS i DESCRIPTORS h IDENTIFIERS/OPEN ENOEO TERMS l COSATI 1 kill liloup 1* DISTRIBUTION STATEMENT RELEASE TO PUBLIC It SECURITY CLASS (rhilRtport) UNCLASSIFIED J1 NO OF PAGES 18 MW[AWf!6r""w' JJ PRICE ¦PA Parm tttO-t (»-7l) { ------- |