L i t e r a t u r e Cited
sei. 197%27, 307. (2) Schdscha, E. B.; Pratt, P. F.; Kinjo, T.; Amar A., J. Soil S C ~sot. . Am. Proc. 1972,36, 912. (3) Barrow, N. J.; Shaw, T. C. J . Soil.Sci. 1979,30, 53. (4) Ryden, J. C.; Syers, J. K. J . Soil Sci. 1975,26, 395. ( 5 ) Singh, B. B.; Tabatabai, M. A. Commun. Soil Sci. Plant Anal. 1977,8, 97. ( 6 ) Barrow, N. J. Soil Sei. 1972,113, 175. (7) Watanabe, F. S.; Olsen, S. R. Soil Sci. SOC.Am. Proc. 1965,29, 677. (1) Helyar, K. R.; Munns, D. N.; Burau, R. G. J . Soil
(8) Weaver, C. E.; Pollard, L. D. “The Chemistry of Clay Minerals”; Elsevier: New York, 1973; pp 141-3. (9) Shainberg, I. Int. Congr. Soil Sci., gth, 1968 1968, I, 577. (10) Lindsay, W. L.; Vlek, P. L. G. In “Minerals in Soil Environment; Dixon, J. B., Weed, S. B., Eds.; Soil Science Society of America: Madison, WI, 1977; pp 639-72. (11) Hall, J. K.; Baker, D. E. Soil Sei. SOC.Am. Proc. 1971, 35, 876.
Received for review May 21,1980. Accepted September 22,1980. This work is published as South Dakota Agricultural Experiment Station Paper No. 1593.
Coal-Liquefaction Products, Shale Oil, and Petroleum. Acute Toxicity to Freshwater Algae Jeffrey M. Giddings” and Jacob N. Washington Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830
Water-soluble fractions (WSFs) of eleven coal-liquefaction products, five shale-oil products, and six petroleum products were tested for acute toxicity to freshwater algae. The coalliquefaction products inhibited algal photosynthesis at WSF concentrations two orders of magnitude lower than the petroleum products; shale-oil products were intermediate in toxicity. Introduction
Product spills are among the major sources of potential environmental impact from coal-liquefaction and shale-oil technologies. Oils derived from coal or shale are generally richer in phenolics, aromatic amines, and other water-soluble organic classes than are petroleum products ( 1 - 3 ) . Spills of synthetic oils may therefore affect aquatic ecosystems differently from spills of conventional oils. We have compared the acute toxicity to algae of the water-soluble fractions (WSFs) of synthetic and petroleum-derived oils, as a first step in investigating their relative hazards to aquatic life. The initial results indicate that coal-liquefaction products are substantially more toxic to freshwater algae than are petroleum products, with shale-oil products intermediate in toxicity. Materials T e s t e d
The oils we tested are listed in Table I. Sample P-2, a No. 2 diesel fuel, was purchased from a local distributor; all other oils were obtained from the U.S. Environmental Protection Agency/Department of Energy (EPA/DOE) Fossil Fuels Research Materials Facility a t Oak Ridge National Laboratory (4).
We tested WSFs rather than whole oils because acute toxicity from oil spills is generally caused by the oil’s water-soluble components ( 5 - 7 ) . The WSFs were prepared by the addition of one part of oil to eight parts of distilled water in a closed glass vessel. The mixtures were gently stirred for 16 h in the dark to prevent light-induced chemical changes (8-13). The aqueous phase was then separated from the oil and filtered (Whatman No. 41 filter paper). Extracts prepared under these conditions contain very few oil droplets ( 1 4 ) . Algal growth-medium ingredients (15)were added, and the WSFs were diluted in fresh algal medium for testing a t 10, 1, and 0.1% concentrations. 106
Environmental Science & Technology
Algal T o x i c i t y T e s t Procedure
Acute toxicity of the WSFs was assessed by measuring short-term photosynthetic inhibition of S e l e n a s t r u m capric o r n u t u m (a green alga) and Microcystis aeruginosa (a blue-green alga). Actively growing (4-7 day old) unialgal cultures were concentrated by centrifugation and resuspended in the test solution in 125-mL BOD bottles for 4 h; photosynthesis was measured by the (14C)bicarbonatemethod (16, 1 7 ) during the final 2 h of exposure. Details of the algal culture conditions and of the bioassay procedure have been described previously ( 1 8 ) . Each WSF concentration was tested in duplicate or triplicate; three to five replicate controls were included in each experiment. A one-tailed Student’s t-test was used to determine significant inhibition of photosynthesis ( P 50.05). On the ?verage, inhibition was statistically significant if photosynthesis was less than or equal to 86%of the controls (range 69-94% over all experiments). Results
Table I1 presents the bioassay results. The petroleum products were nontoxic a t 10%WSF and less. Similar results have been reported for other algae (19-23). The lighter, refined oils (P-1and P-2) were more toxic than the No. 6 fuel oils, as has been noted by other workers (5-7,24-26). Three of the petroleum products were nontoxic to S. capricornutum a t 100%WSF. The WSFs of refined shale-oil products (SH-4 and SH-5) were similar in toxicity to those of the petroleum products (Table 11).The shale-oil residual, a No. 6 fuel oil, was more toxic than any of its petroleum equivalents; S. capricornutum was inhibited by 1%WSF of this oil. Crude and hydrotreated shale oil were also more toxic than the petroleum WSFs, with significant inhibition a t WSF concentrations of 1-10%. Hydrotreatment of the crude shale oil reduced its toxicity to both species. Most of the coal-liquefaction products were toxic to both species a t 1%WSF; four of them inhibited S. capricornutum a t 0.1% (Table 11).A comparison of the results for CL-2-CL-5 indicates that hydrotreatment of increasing severity reduced the toxicity of this oil to M . aeruginosa but not to S. capricornutum.
The relative toxicities of the WSFs we tested reflected the solubility of the aromatic fractions of the oils. T o estimate aromatic concentrations. we measured the absorbance of the
0013-936X/81/0915-0106$01.OO/O
@ 1981 American Chemical Society
Table 1. Oils Tested for Acute Toxicity to Freshwater Algae EPAlDOE no.
sample
CL-1
1701
CI-2 CL-3
1601 1602
CL-4 CL-5
1603 1604
8.8 12.0 9.2 2.8
fuel oil blend, noncatalytic coal liquefaction raw distillate, catalytic coal liquefaction same as CL-2, low-severity hydrotreatment same as CL-2, medium-severity hydrotreatment same as CL-2, high-severity hydrotreatment
20.4 2.9
atmospheric still overhead, catalytic coal liquefaction atmospheric still bottoms, catalytic coal liquefaction
CL-6 CL-7
1308 1309
cL-a
1310
2.4
1312
21.6
1313
atmospheric still bottoms, catalytic coal liquefaction vacuum still overhead, catalytic coal liquefaction
CL-9
vacuum still overhead, catalytic coal liquefaction atmospheric still overhead, catalytic coal liquefaction
CL-11
1314
5.9 1.2
SH-1
4601
2.8
crude shale oil, above-ground retorting
SH-2
4602
0.50
hydrotreated shale oil
SH-3 SH-4
4607 4608
0.16 0.007
hydrotreated shale oil, residue shale oil JP-5 product
SH-5 P- 1
4610 4616
0.044
shale oil DFM product
0.24
petroleum DFM
b
petroleum No. 2 diesel fuel petroleum JP-5
CL-10
a
description
A254 a
25.6
P-2 P-3
4614
0.088 0.060
P-4 P-5
5401 5402
0.096 0.018
petroleum No. 6 fuel oil petroleum No. 6 fuel oil
P-6
6101
ND
petroleum No. 6 fuel oil
Absorbance of water soluble fractlon at 254 nm measured with a Perkin-Elmerspectrophotometer Water-soluble fractions were diluted as necessaryto read Diesel fuel purchasedfrom local distributor. ND = not determined
A2s4 below 1.0.
Table II. Response of Selenasfrum capricornutum and Microcysfis aeruginosa to Water-Soluble Fractions of Coal-Liquefaction, Shale-Oil, and Petroleum Productsa S. capr/cornulum 10%
0.1 %
1 Yo
CL- 1
102
73
CL-2
-
60
sample
CL-3 CL-4 CL-5 CL-6 CL-7
WSF concn
90' 114
+
66 * 71 *
0.1%
11"
1'
99
82"
1*
3" 7"
2"
-
76' 71
2' 2"
94
2"
103 74 *
4"
56
1*
43 *
2*
5"
2'
3*
68' 64"
15' 0"
47 47 *
3" 4"
2"
93 99
1'
85
27'
3*
1"
CL-8 CL-9
73 61 *
CL-10
99
35
2'
CL-11 SH- 1
65 *
34 *
3*
-
94
SH-2
-
113
SH-3
108
SH-4 SH-5
103
82"
M. aeruginosa 1% 10%
100%
4"
-
1"
100%
0' 1' 1' 1" 1"
1" 1"
-
114 91
94 29 *
1"
85
46 *
4"
2"
21
1"
1'
2*
70 * 84
10"
82 * 24 *
-
13"
94
99 84 *
-
-
110 93
101 106
P- 1
-
99
90
1"
P-2 P-3 P-4 P-5 P-6
95 99 96 87 111
97 108 112 101
91 109 106 98
39 * 90 90" 124
98
97
93
3" 2"
1'
67*
1"
101
84 *
26 *
-
-
-
-
-
-
-
-
-
97
100
98
50"
-
-
-
-
87 100 114
92 110 105
88 103 103
41 * 83 75'
The values shown are photosynthesisexpressed as a percentage of controls. Asterisks indicatesignificant photosynthetic inhibition( P = 0.05). Dashes indicate tests not performed. a
Volume 15, Number 1, January 1981
107
WSFs a t 254 nm, the absorption maximum for benzene. The absorbances of coal-liquefaction-product WSFs were two orders of magnitude higher than those of petroleum-product WSFs (Table I). The most toxic shale-oil samples had absorbances close to those of the liquefaction products; the less toxic shale oils resembled petroleum products. Although absorbance a t 254 nm is only an approximate measure of aromatic content (27),these data suggest that the high toxicity of coal-liquefaction products is due in part to their high solubility in water. Total organic carbon (TOC) determinations vsing a Beckman TOC Analyzer (28) on two of these WSFs support this conclusion: TOC concentrations of WSFs of P-2 and CL-1 were 105 and 5000 mg/L, respectively (29).Causes qf this high solubility have yet to be determined, but the abundance of phenols, amines, and other polar aromatic compounds in coal-derived oils (1-3) is probably an important factor. Such compounds are readily removed from oil by dissolution (23,30),so the toxicity of a coal-liquefaction product may decline rapidly as the oil weathers in an aquatic environment. Chemical changes that might occur after a spill of coal-derived oil are currently under investigation. The much greater acute toxicity of synthetic oils compared to natural oils, consistent over a range of product types, implies a need for further research on the ecological hazards of synthetic liquid fuels. Ideally, such a hazard assessment could be completed before these advanced fossil energy technologies become commercialized, so that appropriate precautions may be taken to minimize their environmental impact. For example, phenols and amines in coal liquids could be destroyed by hydrotreating (31) within the liquefaction plant, thereby reducing the toxicity of products transported from the site.
Acknowledgment We thank J. Trabalka and S. Herbes for suggestions on the manuscript.
Literature Cited (1) Braunstein. H. M.. Cooenhaver, E. D., Pfuderer, H. A., Eds. Oak Ridge, T N , 1977, Oak-Ridge National Laboratory Report No.
ORNLIEIS-94. 121 Bauphman. G. L. “Svnthetic Fuels Data Handbook”, 2nd ed.; Cameyon Engineers: Denver, CO, 1978. (3) Griest. W. H.: Guerin. M. R.: Clark, B. R.: Ho, C.-h.; Rubin, I. B.; Jones, A. R. In “Symposium on Assessing the Industrial Hygiene Monitoring Needs for the Coal Conversion and Shale Oil Industries”; Brookhaven National Laboratory, Nov 1978, in press. (4) Griest, W. H.; Coffin, D. L.; Guerin, M. R. Oak Ridge, T N , 1980, Oak Ridge National Laboratory Report No. ORNL/TM-7346. ( 5 ) Evans, D. R.; Rice, S. D. Fish Bull 1974,72, 625.
108
Environmental Science & Technology
(6) Moore, S.F.; Dwyer, R. L. Water Res. 1974,8, 819. (7) Rice, S. D.; Short, J. W.; Karinen, J. F. In “Fate and Effects of Petroleum Hydrocarbons in Marine Organisms and Ecosystems”; Wolfe, D. A., Ed.; Pergamon Press: New York, 1977; p 78. (8) Burwood, R.; Speers, G. C. Estuarine Coastal Mar. Sci. 1974,2, 117. (9) Frankenfeld, J. W. In “Conference on Prevention and Control of Oil Spills, 1973, Washington, D.C.”; American Petroleum Institute: New York, 1973; p 485. (10) Klein, A. E.; Pilpel, N. Water Res. 1974,8, 79. (11) Larson, R. A.; Bott, T. L.; Hunt, L. L.; Rogenmuser, K. Enuiron. Sci. Technol. 1979,13, 965. (12) Larson, R. A.; Hunt, L. L.; Blankenship, D. W. Enuiron. Sci. Technol. 1977,11, 492. (13) Majewski, J.; O’Brien, J.; Barry, E.; Reynolds, H. Enuiron. Lett. 1974, 7, 145. (14) Shaw, D. G.; Reidy, S.K. Enuiron. Sci. Technol. 1979, 13, 1259. (15) Miller, W. E.;Green,J. C.; ShiroyamaT. Washington,D.C., 1978, US.Environmental Protection Agency Report No. EPA-600/978-018. (16) Schindler, D. W.; Schmidt, R. V.; Reid, R. A. J . Fish. Res. Board Can. 1972,29, 1627. (17) Theodorsson, P.; Bjarnason, J. 0. Limnol. Oceanogr. 1975,20, 1018. (18) Giddings, J. M. Bull. Enuiron. Contam. Toxicol. 1979, 23, 360. (19) Johnson, F. G. In “Effects of Petroleum on Arctic and Subarctic Marine Environments and Organisms”; Malins, D. C., Ed.; Academic Press: New York, 1977; p 271. (20) Kauss, P. B.; Hutchinson, T. C. Enuiron. Pollut. 1975,9, 157. (21) Nuzzi, R. In “Conference on Prevention and Control of Oil Spills, 1973,Washington, D.C.”; American Petroleum Institute: New York, 1973; p 809. (22) Pulich, W. M., Jr.; Winters, K.; Van Baalen, C. Mar. Biol. 1974, 28, 87. 123) Winters. K.: O’Donnell, R.: Batterton. J. C.: Van Baalen, C. Mar. Riol. 1976,36, 269. (24) Anderson, J. W.; Neff, J. M.; Cox, B. A.; Tatem, H. E.; Hightower, G. M. Mar. Biol 1974,27, 75. (25) Gordon, D. C., Jr.; Prouse, N. J. Mar. Biol 1973,22, 329. (26) Van Gelder-Ottway, S.In “Marine Ecology and Oil Pollution”; Baker, J. M., Ed.; Wiley: New York, 1976; p 287. (27) Larson, R. A.; Weston, J. C. Bull Enuiron Contam. Toxlcol 1976,16, 44. (28) Lysyj, 1.; Russell, E. C. Water Res 1974,8, 863. (29) Giddings, J. M.; Parkhurst, B. R.; Gehrs, C. W.; Millemann, R. E. Bull. Enuiron. Contam Torzcol. 1980,25, 1. (30) Guard, H. E.: Hunter. L.; DiSalvo, L. H. Bull Environ Contam Toxicol. 1975,14, 395. (31) Tan, G.; deRosset, A. J. Washington, D.C., 1978, Department of Energy Report No. FE-2566-20.
Received for review June 9,2980. Accepted September 9, 1980. This Research was sponsored by the Office of Health and Environmental Research, U.S. Department of Energy, under contract W-7405eng-26 with Union Carbide Corp. Publication No. 1612, Enuironmental Sciences Diuision, ORNL.
