EPA-600/3-84-067 May 1984 ACUTE TOXICITY OP EIGHT LABORATORY-PREPARED GENERIC DRILLING FLUIDS TO MYSIDS (Mysidopsis bahia) by T.W. Duke, P.R. Parrish,, R.M. Montgomery, S.D. Macauley, J.M. Macauley, and G.M. Gripe Environmental Research Laboratory Sabine Island Gulf Breeze, Florida 32561 ENVIRONMENTAL RESEARCH LABORATORY OFFICE OF RESEARCH AND DEVELOPMENT U.S. ENVIRONMENTAL PROTECTION AGENCY GULF BREEZE, FLORIDA 32561 ------- ERRATA ACUTE TOXICITY OF EIGHT LABORATORY-PREPARED GENERIC DRILLING FLUIDS TO MYSIDS (Mysidopsis bahia) by T.W. Duke, P.R. Parrish, R.M. Montgomery, S.D. Macauley, J.M. Macauley, and G.M. Cripe EPA-600/3-84-067 May 1984 Page 6, line 6. "...same as those " Page 10, line 10. "...oil-free drilling fluids,...." Page 12, line 5. "CENTEC3" Page 12, line 18. "aCentec Analytical Service " Page 14, line 9. "Polyanionic Cellulose" Page 18, line 11. "Definitive #2 5% 18% 18% - 42 80% 100% - - - -" OCT * 5189! ------- DISCLAIMER The InforM-tion In this document has been funded by the U.S. Environmental Protection Agency. It has been subject to the Agency's peer and administrative review and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the U.S. Environmental Protection Agency; nor does mention of trade names or cornnercial products constitute endorsement or reconmendation for use. ii ------- FOREWORD The protection of our estuarine and coastal areas from damage caused by toxic organic pollutants requires that regulations restricting the introduction ot these compounds into the marine environment be formulated on a sound scientific basis. Accurate information describing concentration- response relationships for organisms and ecosystems under varying conditions is required. The Environmental Research Laboratory, Gulf Breeze, contributes to satisfying this information requirement through research programs aimed at determining: o the effects of toxic organic pollutants on individual species and communities of organisms. o the effects of toxic organics on ecosystems processes and components. o the significance of chemical carcinogens in the estuarine and marine environments. This report addresses the acute toxicity of eight generic drilling fluids to mysids, Mysidopsis bafaia, and the toxicity of two of the fluids containing a mineral oil to these organisms. The tests were conducted in response to a request from the Office of Water Regulations and Standards and tested according to procedures prescribed by the Office. /r, 7s A "i t ftenry F. Knos Director Environmental Research Laboratory Gulf Hrpeze. Florida iii ------- ABSTRACT Acute toxicity tests were conducted during August-September 1983 with eight laboratory-prepared generic drilling fluids (also called muds) and mysids (Mysidopsis bahia) at the U.S. Environmental Protection Agency's Environmental Research Laboratory. Gulf Breeze, Florida. Two of the drilling fluids were tested at the Environmental Research Laboratory, Narragansett, Rhode Island, to confirm the validity of the tests conducted at Gulf Breeze. The test material was the suspended participate phase (SPP) of each drilling fluid. The SPP was prepared by mixing volumetrically 1 part drilling fluid with 9 parts seawater and allowing the resulting slurry to settle for one hour. The material that remained in suspension was the SPP. Tbxicity of the SPP of the drilling fluids ranged from a 96-hour LC50 (the concentration lethal to 50% of the test animals after 96 hours of exposure) of 2.7% for a KC1 polymer mud to 65.4% for a lightly treated lignosulfonate mud. No median effect (50% mortality) was observed in three drilling fluids — a non-dispersed mud, a spud mud, and a seawater- freshwater gel mud. Two of the generic drilling fluids to which mineral oil had been purposely added were also tested at Gulf Breeze. The addition of the mineral oil increased the acute toxicity of each fluid to mysids. When 1% mineral oil was added, the 96-hour LC50 changed from Ti.6% to 13.5% for fluid #2, a seawater lignosulfonate mud, and from 29.3*5 to 7.1% for fluid *8, a freshwater lignosulfonate mud. Addition of 5? and u)% mineral oil further increased toxicity. ------- CONTENTS Foreword lii Abstract iv Tables vi Acknowledgment. vii Introduction 1 Materials and Methods A. Drilling Fluids 2 B. Reference Toxicant 3 C. Methods for Drilling Fluid Tests 3 D. Methods for Reference Toxicant (Positive Control) Tests ..... 5 E. Test Animals 6 F. Statistical Analyses 6 Results and Discussion A. Generic Drilling Fluids 8 B. Mineral dl-Contaminated Drilling Fluids 9 Literature Cited 11 Appendices A. Chemical and Physical Characteristics of the Mineral Oil Used 23 B. Mortality Data 24 ------- TABLES Nunber Page 1 Treatment of eight generic drilling fluids 12 2 Source and composition of eight generic drilling fluids 13 3 Results of acute toxicity tests with eight generic drilling fluids and raysids (Mysidopsis bahia), Gulf Breeze 15 4 Generic drilling fluid concentrations 16 5 Relationship of the weight of suspended material in the suspended particulate phase of eight generic drilling fluids to toxicity 17 6 Results of three acute toxicity tests with generic drilling fluid #1, Gulf Breeze 18 7 Results of acute toxicity tests with two generic drilling fluids, Gulf Breeze and Narragansett 19 8 Comparative toxicity of two generic drilling fluids without and with mineral oil 20 9 Results of acute toxicity tests with two generic drilling fluids containing mineral oil 21 10 Results of three acute toxicity tests with generic drilling fluid #8-05, Gulf Breeze 22 vi ------- ACKNOWLEDGMENTS The cooperation of the Environmental Research Laboratory. Narragansett, Rhode Island, is gratefully acknowledged. Mr. S. Schimmel, U.S. Environmental Protection Agency, served as coordinator for the two tests conducted there; Messrs. T. Coffee and D. Wayne of the Edgerton Research Laboratory, New England Aquarium, Boston, Massachusetts, performed the tests under contract to the Narragansett laboratory. At Gulf Breeze, personnel support was provided by Georgia State University, Cooperative Agreement CR809370, for Mr. R. Parrish during most of the testing program and by the University of West Florida, Cooperative Agreement CR807417, for Mr. R. Montgomery and Mrs. S. Macauley during the entire testing program. vii ------- INTRODUCTION The purpose of this study was to determine the acute toxicity of eight laboratory-prepared generic drilling fluids to mysids (Mysidopsis bahia) according to methodology prescribed by the Effluent Guidelines Division, Office of Water Regulations and Standards, U.S. Environmental Protection Agency (EPA). Toxicity tests with all fluids were conducted at the EPA Environmental Research Laboratory, Gulf Breeze (ERL/GB), Florida, during August-September 1983, and two confirmatory tests were conducted at the EPA Environmental Research Laboratory, Narragansett, Rhode Island, during the same time period. Acute toxicity tests were also conducted at ERL/GB during September- October 1983 with two of the generic drilling fluids that had been purposely contaminated with mineral oil. The purpose was to determine the toxicity of mineral oil in representative drilling fluids. The generic drilling fluid concept was developed jointly by EPA's Region II and industry to provide EPA information on the impact of drilling fluids and components of the fluids released into the environment without requiring each drilling operator to perform repetitious toxicity tests and chemical analyses. The eight generic drilling fluids include virtually all water-based fluids used on the U.S. Outer Continental Shelf. Only major components of the generic fluids are specified and additional information concerning the effects of speciality additives must be submitted to EPA prior to their discharge (Petrazzulo, 1983). The generic fluid concept is now being employed by EPA Regional Offices involved In the permitting process (EPA, 1983). ------- MATERIALS AND METHODS A. Drilling Fluids The eight laboratory-prepared generic drilling fluids to be tested were received at ERL/GB during June and July 1983. They were sent via connercial airlines by each femulator. Bach drilling fluid was contained in four 3.5-gallon plastic buckets with lids tightly sealed. The buckets were shipped in plastic ice chests, sane of which contained wet ice or "blue ice." All buckets were cool to the touch when they arrived at ERL/GB. Upon receipt, each bucket of fluid was immediately placed in a large walk-in cooler with temperature maintained at approximately 4°C until the contents of each bucket were combined, mixed, and recontainerized. The purpose of mixing was to assure homogeneous samples for testing and/or chemical analyses. Mixing was accomplished by emptying each bucket of a fluid into a large plastic container. The fluid was stirred by hand with a large Teflon* paddle as approximately half of the contents of each bucket were alternately emptied. The fluid was then stirred for an additional 2-5 minutes, and was poured back into three of the original buckets that had been washed with tap water (except for the first fluid received, EPA-83-00800, which was put into new buckets). Drilling fluid equivalent to the contents of approximately one bucket (about 11 liters) was placed in new 1-liter plastic jars. All containers were labeled and capped (new lids were used on buckets because the original lids were destroyed when opened) after the air space above the fluid was flooded with nitrogen. The caps/lids were securely fastened, and the containers were placed in the walk-in cooler. A detailed account of the treatment of each drilling fluid from the date of receipt to testing and/or transshipment is given in Table I; the source and composition of each fluid are listed in Tible 2. Appendix A 2 ------- contains a description of the physical and chemical characteristics of the mineral oil added to two of the generic drilling fluids. B. Reference Toxicant Sodiun lauryl sulfate (dodecyl sodium sulfate) was used as a reference toxicant for the positive control. The chemical used was manufactured by Sigma Chemical Company, No. L-5750, Lot. 42F-0039, and was approximately 95% pure. Chemical from the same lot was used in the positive control tests at Gulf Breeze and Narragansett. C. Methods for Drilling Fluid Tests Test methods followed those proposed by Petrazzuolo (1983) with the following exceptions: (1) Natural seawater from the ERL/GB seawater system was used instead of artificial seawater. The natural seawater was pumped from Santa Rosa Sound and filtered through sand and a 5-micrometer fiber filter; salinity was controlled at 20*2 parts per thousand by the addition of deionized water, and temperature was controlled by a commercial chiller; (2) 5*l-day-old mysids were used instead of 4±lday-old mysids; (3) Test mixtures were aerated; and (4) For the mineral oil tests, glassware was washed with petroleum ether to assure removal of the oil. At the outset, one or more 1-liter jars of the drilling fluid(s) to be tested were selected impartially. The fluid was mixed in the jar for at least 30 minutes by using a 1,600-rpm electric stirrer which turned a four- blade stainless steel stirrer. While the fluid was stirring, seawater was aerated in a container in an ice-bath. To prepare the suspended particulate phase of the drilling fluid. ------- 800 railliliters of the chilled seawater was added to a 2-liter Erlenmeyer flask. Then, 200 ndlliliters of the well-etirred drilling fluid was added to the flask, ifare seawater (1,000 mililiters) was added to bring the contents of the flask to the 2-liter mark. This 1-part fluid:9-part seawater slurry was placed on a magnetic stirrer and mixed for at least 5 minutes. The pH was measured and, if necessary, glacial acetic acid was added to bring the pH of the slurry within 0.2 pH units of the seawater, as directed by the test method. (If too much acid was added, sodiun hydroxide was added as needed to increase pH.) The slurry was mixed for an additional 5 minutes if acid was added and then allowed to settle for 1 hour. The suspended phase (that is, all the liquid and suspended particulate above the settled or solid phase) was then decanted into a separate container, and pH and dissolved oxygen (DO) concentration were measured. If necessary, pH was again adjusted. Also, if DO was less than 65% of saturation, the suspended particulate phase was aerated, usually for 5 minutes. The appropriate volune of this 100% suspended particulate phase or seawater or both was added to a 2-liter Carolina culture dish (the total volune in each dish was 1 liter) to prepare the test and control mixtures. The mixtures were then stirred for approximately 30 minutes; the DO, pH, temperature and salinity were measured; and test animals were added to the dishes. The number of animals exposed to a drilling fluid and the number of replicates varied. For range-finding tests, 10 mysids were added to each of 4 concentrations (100%, 50%, 10%, and 1% suspended particulate phase) and a seawater control, none of which was replicated. For definitive tests, 20 mysids were added to a seawater control and each of 5 concentrations (except only 3 concentrations were tested in those cases where no median effect, that is, 50% mortality, occurred in 100% suspended particulate ------- phase in the range-finding test). Three replications of each treatment gave a total of 60 animals per treatment. For all tests, the animals in each dish were placed in holding cups fabricated by gluing a collar of 363-fliicrometer mesh nylon screen to a 15-centimeter wide glass Petri dish with silicone sealant. The nylon screen collar was approximately 5 centimeters high. After measurement of water quality characteristics (DO, pH, salinity, and temperature) and addition of animals, the dishes were stacked three-high, with a cover on the top dish, and placed in an incubator. The temperature controller was set at 21°C and the light controller at 14 hours light:10 hours dark. All treatments were aerated at a volume estimated to be 50-140 cubic centimeters/minute during the tests. Air was delivered to each dish through polyethylene tubing (0.045-inch inner diameter and 0.062-inch outer diameter) by a small aquarium pump. Water quality was measured at 24-hour intervals, but the turbidity of most fluids prevented 24-hour observations of test animals. After 96 hours, the test was terminated. If the solution was turbid, the cups were flushed with seawater until the animals became visible. Live animals were then removed by pipette and counted. Quality assurance was ensured by counting the control animals, placing them back in the holding cup and flushing them with seawater, and then recounting them. Test methods used at Narragansett also followed Petrazzuolo's (1983) proposed methods. A report on the Narragansett tests is maintained at the Environmental Research Laboratories, Gulf Breeze and Narragansett. D. Methods for Reference Toxicant (Positive Control) Tests Test methods were those used for the drilling fluid tests, except that the test material was prepared by weighing one gram of -sodium lauryl sulfate on an analytical balance, adding the chemical to a I00-miHi liter volumetric 5 ------- flask, and bringing the flask to volune with deionized water. The test mixtures were prepared by adding 0.1 milliliter of the stock solution for each part per million desired to one liter of seawater. The mixtures were stirred briefly, water quality was measured, animals were added to holding cups, and the test was begun. Incubation and monitoring procedures were the same as these for the drilling fluids. E. Test Animals Mysids (Mysidopsis bahia) for the drilling fluid and reference toxicant tests were cultured at the Gulf Breeze and Narragansett laboratories. In addition, seme mysids used for testing at Gulf Breeze were purchased from a connerical supplier, the origin of whose stock was the same as the laboratory stock. All raysids (5±1 days old) were fed Artemia salina nauplii (32-48 hours post-hydration) during holding and testing. F. Statistical Analyses Mortality data from the drilling fluid tests and the reference toxicant (positive control) tests were subjected to statistical analyses. A 96-hour LC50 (the concentration lethal to 50% of the test animals after 96 hours of exposure) was calculated for each drilling fluid (if the mortality data were amenable) and for each reference toxicant test by using the moving average method (Kendall and Stuart, 1973, and Stephan, 1977). The 95% confidence limits were also calculated. For tests where control mortality was £10%, no correction was made and the uncorrected data were used to compute LCSO's and 95% confidence limits. For one mineral oil-contaminated drilling fluid and three reference toxicant tests at Gulf Breeze, the control mortality was >10% and data were corrected by using Abbott's formula (Abbott, 1925). The data used in drilling fluid LC50 calculations are contained in Appendix B. ------- Data froai the Gulf Breeze testa with the eight generic drilling fluids (Appendix B) were also analyzed by SAS*, based on the probit method (Plnney, 1971). A correction was made for all tests in which there was control mortality.1 To estimate the association between the mineral oil content and toxicity. data were analyzed by using Spearman's coefficient of rank correlation (Steel and Torrie, 1980). 1 Analyses performed by R. Clifton Bailey, U.S. E?A, ^rr^ram Integration and Evaluation Staff (WH-586), Office of Water Hen-iiations and Standards, Washington, DC 20460. ------- RESULTS AND DISCUSSION A. Generic drilling fluids The range of toxicity of eight laboratory-prepared generic drilling fluids to mysids was considerable. The 96-hour LCSO's were from 2.7% suspended particulate phase (fluid #1) to 65.4* (fluid #7). An LC50 could not be calculated for three fluids — #4, #5, and #6 — because no median effect (50* mortality) occurred (Table 3). It should be noted that these tests were not designed to identify the constituents in drilling fluid #1 that caused it to be more toxic than the other fluids. The acute toxicity of the drilling fluids was generally related to the weight of the suspended material in the suspended particulate phase of each fluid, except for fluid #1. For example, fluid *7 contained 17.12 grams of suspended particulate matter per liter of the suspended particulate phase and the 96-hour LC50 was 65.4%. The more toxic fluid #3 contained 25.12 grams of suspended matter per liter, with a 96-hour LC50 of 16.3% (Tables 4 and 5). The response of the mysids to the reference toxicant, sodium lauryl sulfate, showed that the test animal populations were in suitable condition for the toxicity tests. In five tests, the 96-hour LCSO's were from 3.4 ppm to 7.5 ppn (Table 3). These are in accord with the literature and with unpublished data from Gulf Breeze and a commercial testing laboratory. The reference toxicant LCSO's obtained at Gulf Breeze and Narragansett were similar even though the brood stocks and natural seawater were different. Water quality was generally acceptable. The most serious problem was dissolved oxygen (DO) concentration. The oxygen demand of some drilling fluids (#3 and #8, for example) was high. The suspended particulate phase had to be aerated before testing began, and even with aeration during 8 ------- the test, DO concentrations were low. In only a few instances, however, was DO less than the minimally acceptable 65% of saturation. (NOTE: Raw data sheets are maintained at ERL/GB). Heproducibility of results from test to test at Gulf Breeze was excellent. With drilling fluid #1, for example, three different tests were conducted: a range-finding test, a definitive test (which was repeated because of an unacceptable reference toxicant test), and a second definitive test. The results showed similar concentration-response relationships in all three tests (Table 6). The interlaboratory agreement of test data from Gulf Breeze and Narragansett was equally good. The validity of the Gulf Breeze tests were confirmed by tests with two drilling fluids (#1 and *S) at Narragansett. The 96-hour LC50 for fluid #1 was almost exactly the same at both laboratories (Table 7). The results of the tests with fluid *S were similar: Narragansett observed no mortality in 100% suspended participate phase, whereas Gulf Breeze recorded 12% mortality in that concentration. Considering the nature of the test material and other possible sources of variability, this represents a more than satisfactory duplication of test results. The slight differences in computed median effect concentrations 'J^ere not considered significant. Whether there was correction for control mortality or not, and whether the moving average method or the probit method was used, there was excellent agreement among the toxicity test results. B. Mineral oil-contaminated drilling fluids The addition of mineral oil to laboratory-prepared generic drilling fluids #2 and #8 dramatically increased their acute toxicity to mysids. When 1% mineral oil was added, the 96-hour LC50 changed from 51.6% to 13.4% 9 ------- for fluid #2 and from 29.3% to 7.1% for fluid #8. Addition of 5% and 10% mineral oil further increased toxicity (Table 8). There was a significant negative correlation between mineral oil content and the 96-hour LC50 for each fluid; Spearmans's r » -0.976 with a probability <0.0001. The response of the mysids to the reference toxicant was within an acceptable range, demonstrating that the test animals were in suitable condition (Table 9). While the reproducibility of results from test to test was not as good as with oil-free drilling fluid, the test results did show similar concentration-response relationships (Table 10). The variation was probably caused by the volatility of the mineral oil and the need to aerate the suspended particulate phase before testing to achieve acceptable dissolved oxygen concentrations. The presence of mineral oil in the generic drilling fluids did not adversely affect water quality. The DO, pH, salinity, and temperature were all within acceptable ranges during the tests. 10 ------- LITERATURE CITED Abbott, W.S. 1925. A Method of Computing the Effectivenesss of an Insecticide. J. Econ. Entoraol. 18: 265-267. Finney. D.J. 1978. Statistical Methods in Biological Assay, 3rd ed. Griffin Press, London. 508 pp. Kendall, M.G. and Stuart, A. 1973. The Advanced Theory of Statistics, Vol. 3, 3rd ed., Hafner Publishing Co., New York, NY, pp. 342-430. Petrazzuolo, G. 1983. Proposed Methodology: Drilling Fluids Toxicity Test for the Offshore Subcategory; Oil and Gas Extraction Industry. Technical Resources, Inc., Bethesda, MD 20817. DRAFT dated May 19. 1983. Steel, R.G. and J.H. Torrie. 1980. Principles and Procedures of Statistics, 2nd ed. McGraw-Hill, New York, NY. 633 pp. Stephan, C.E. 1977. Methods for Calculating an LC50. In: Aquatic Toxicity and Hazard Evaluation. ASTM STP 634, F.L. Mayer and J.L. Hamelink, Eds., American Society for Testing and Materials, Philadelphia, PA, pp. 65-84. U.S. Environmental Protection Agency. 1983. Issuance of Final General NPDES Permits for Oil and Gas Operations on the Outer Continental Shelf (CCS) of Alaska; Norton Sound and Beaufort Sea. Federal Register Vol. 48, No. 236, December 7, 1983, pp. 54881-54897. 11 ------- TABLE 1. Treatment of eight generic drilling fluids received at U.S. EPA, Gulf Breeze, Florida. TRANSSHIPPED CENTIC* GENKKIC MUDS EPA-83-O01 EPA-83-002 EPA-83-003 KPA-83-4XM KPA-83-005 KPA-H3-4XKi LPA-83-OO7 KPA-83-OOB KtiCfcllVKD 13 July 83 ti July 83 16 July 83 19 July 83 8 July 83 8 July 83 ti July 83 28 June 83 MIXED 14 July 83 8 July 83 18 July 83 20 July 83 11 July 83 14 July 83 8 July 83 29 June 83 SHIPPED 14 July 83 12 July 83 21 July 83 21 July 83 14 July 83 14 July 83 12 July 83 7 July 83 RECEIVED 15 July 83 13 July 83 22 July 83 22 July 83 15 July 83 15 July 83 13 July 83 8 July 83 NARRAGANSETT SHIPPED RECEIVED 1 August 83 2 August 83 18 July 83 19 July 83 18 July 83 19 July 83b iL- Analytical Son/ice, Salem, Virginia, for chemical analyses. NOI. tested at Nurrttganuctt. ------- TABLE 2. Source and reported composition of eight generic drilling fluids received at U.S. EPA, Gulf Breeze, Florida. Composition Drilling Fluid Source EPA-83-001, Chrcmalloy KC1 Polymer Mud Component KC1 Drispac (Super-Lo) X-C Polymer Barite Starch Sea water Concentration 50.0 0.5 1.0 283.2 2.0 257.6 grains (g) g g g g milliliters (ml) EPA-83-002, Seawater Lignosulfonate Mud IMCO Services Lime Mud Hughes KPA-83-004, Non-dispersed mud Newpurk Drilling Fluids Attapulgite Chrome Lignosulfonate Lignite Polyanionic Cellulose Caustic Barite Seawater Benitonite Lime Barite Chrome Lignosulfonate Caustic Lignite Distilled water Bentonlte Acrylic Polymer (for suspension) Acrylic Polymer (for fluid loss control) Harite Deionlzed .Water 30.0 pounds per barrel (ppbbl) 15.0 ppbbl 10.0 ppbbl 0.25 ppbbl To pH 10.5-11.0 To bring mud weight to 17-18 pounds per gallon (ppg) As needed 20.06 5.01 281.81 15.04 1.00 8.02 257.04 g g g g ml 13.0 ppbbl 0.5 ppbbl 0.25 ppbbl 190.7 ppbbl 299.6 ppbbl ------- Table 2, continued. EPA-83-005, Spud mud ML Uaroid EPA-83-006, Ul Ichem Seawater/Freshwater Gel Mud EPA-83-007, Lightly Treated Llgnosulfonate Mud EPA-83-008, Freshwater Lignosulfonate Mud Magobar Dresser Dowel1 Bentonlte Lime Barite Seawater/Freshwater Caustic Bentonite Polyaninic Cellulose Sodium Carboxymethyl Cellulose Barite Sodium Hydroxide To pH 12.5 0.5 50.0 1.0 10.0 ppbbl ppbbl ppbbl bbl 20.0 ppbbl 0.50 ppbbl 0.25 20.0 To pH 9.5 ppbbl ppbbl Seawater/Freshwater, 1:1 As needed Bentonite Chrome Lignosulfonate Lignite Soda Ash Carboxymethyl Cellulose Barite Bentonite Chrome Lignosulfonate Lignite Carboxymethyl Cellulose Sodium Bicarbonate Barite Deionized Water 20.0 5.0 3.0 1.0 0.5 178.5 15.0 15.0 10.0 0.25 1.0 487.0 187.0 ppbbl ppbbl ppbbl ppbbl ppbbl ppbbl g g g g g g ml ------- TABLE 3. Results of acute toxicity tests with eight generic drilling fluids and mysids (Mysidopsis bahia), The tests were conducted at U.S. EPA, Gulf Breeze, Florida, during August-September 1983. Drilling Kange-finding Test Fluid (median effect) HI >1% <10% SPPC ff2 >50% <100% SPP 03 >10% <50% SPP //4 No median effect in 100% SPP //5 1(K)% SPP 06 No median et'tect in HXJ% SPP Definitive Testa (96-h LC50 & 95% CL) 2.7% SPP (2.5-2.9) 51.6% SPP (47.2-56.5) 16.3% SPP (12.4-20.2) 12% mortality in 100% SPP 12% mortality in 100% SPP 20% mortality in 100% SPP Positive Controla (96-h LC50 & 95% CL) 5.8 ppirf1 (4.3-7.6) 7.5 ppm (6.9-8.1) 7.3 ppm (6.6-8.1) 3.4 ppm (2.8-4.1) Same as for ffl 6.O ppm (5.4-6.6) Definitive Testb (96-h LC50 & 95% CL) 3.3% SPP (3.0-3.5) 62.1% SPP (58.3-65.4) 20.3% SPP (15.8-24.3) B >50v < I 001. SPP >\C& <50/0 SPP ti5.4% SPP (M.-1-80.-I) 2H.3'i SPP (27.2-31.5) Sante as for (tti SuJiie as for #3 68.2% SPP (55.0-87.4) 30.0% SPP (27.7-32.3) H calculations hy rui'.e; no correction for control mortality unless stated. '' i it h.'ului. mns l>v SAS"01 pruhit; coi'rv CL ton lor all control mortality. Analyses pt-rformed H. Clifton Duiley, U.S. I'.PA, Pny.niiM inu.'gniLion uini l>!vul nation Staff (WM-586), Office of Water Itegulations and Standards, W.islu n^ Li >n , IK' ',i(t Uil). c ']'li«..- t>iis|K.-ii(ti.'il |»art iculuLe pliabo (SPl') was profiartxl hy mixing 1 part drilling fluid with y parts sea water. There lore, ihcse valuet, should be multiplied hy 0.1 in order to relate the l;y dilution tested to the SPP l he whole drilling fluid. (l Corrected for 13% control mortality. ------- TABLE 4. Generic drilling fluid concentrations, based on volumetric preparations of the suspended particulate phase (SPP); and weight of suspended material in the SPP in tests at U.S. EPA, Gulf Breeze, Florida. Fluid #1 #2 #3 #4 #5 #6 #7 #8 Date SPP prepared 15 Aug 83 25 Aug 83 22 Aug 83 18 Aug 83 15 Aug 83 29 Aug 83 29 Aug 83 22 Aug 83 SPP (g/t) 10.54 18.66 25.12 0.0018 0.1570 0.866 17.12 32.19 SPP 96-h LC50 uA/i;ppn* u£/i;ppnk 27,000 2,700 516,000 51,600 163,000 16,300 e c c 654,000 65,400 293,000 29,300 a Based on 1:9 dilution. b Corrected for 1:9 dilution. c No median effect (50% mortality) occurred in 100% SPP. 16 ------- Table 5. Relationship of the weight of suspended material in the suspended particulate phase of eight generic drilling fluids to toxicity teats conducted at U.S. EPA, Gulf Breeze, Florida. Fluid *4 #5 #6 #1 #7 *2 #3 #8 SPP (g/l) 0.0018 0.1570 0.866 10.54 17.12 18.66 25.12 32.19 96-hour SPP* LC50 b b b 2.71 65.4 51.6% 16.3% 29.3% a The suspended participate phase (SPP) was prepared by mixing 1 part drilling fluid with 9 parts seawater. Therefore, these values should be multiplied by O'.l in order to relate the 1:9 dilution tested to the SPP of the whole drilling fluid. b No median effect (50% mortality) occurred in 100% SPP. 17 ------- TABLE 6. Results of three acute toxicity tests conducted with mysids (Mysidopsis and generic drilling fluid #1 at U.S. EPA, Gulf Breeze, Florida. '" data are given as percentages. Exposure Concentration (SPP4) Test Range-finding Definitive #1 Definitive #2 Control 10* 8% 5% 1 10% 15% 11% 2 2.5 3 4 5 _ 18% 100% 11% - 42% 80% 100% 7.5 10 50 100% 100%. 100% 100% - - 100 100% - - a The suspended participate phase (SPP was prepared by mixing 1 part drilling fluid with 9 parts seawater). Therefore, these values should be multiplied by 0.1 In order to relate the 1:9 dilution tested to the SPP of the whole drilling fluid. 18 ------- TABLE 7. Results of acute toxicity tests with mysids (Mysidopsia bahia) and two generic drilling fluids conducted at U.S EPA, Gulf Breeze, Florida, and Narraganaett, Rhode Island, during August-September 1983. Test Location Gulf Breeze Drilling Fluid 96-hour SPP* LC50 #1 2.7% #5 No Median Effect15 95% Confidence Limits 2.5-2.9% Narragansett #1 #5 2.8% No Median Effect5 2. 5-3. Ot a The suspended particulate phase (SPP) was prepared by mixing 1 part drilling fluid with 9 parts seawater. Therefore, these values should be multiplied by 0.1 in order to relate the 1:9 dilution tested to the SPP of the whole drilling fluid. b No median effect (50% mortality) occurred in 100% SPP. 19 ------- TABLE 8 Comparative acute toxicity of two generic drilling fluids without and with mineral oil tested with raysids (Mysidopsis bahia) at U.S. EPA, Gulf Drilling Fluid* #2 #2-01 #2-05 #2-10 #8 #8-01 #8-05 #8-10 Breeze, Florida, during August-October, 1983. 96-hour SPP15 LC50 51.6% 13.5% 1.3% 0.49% 29.3% 7.1% 0.90 0.76% 95% Confidence Limits 47.2-56.5% 11.1-16.9% 1.4-2.2% 0.39-0.62% 27.2-31.5% 5.7-9.0% 0.74-1.1% 0.63-0.87% a The two digits following the generic drilling fluid nunber indicate the percentage of mineral oil in the fluid. b The suspended particulate phase (SPP) was prepared by mixing 1 part drilling fluid with 9 parts seawater. Therefore, these values should be multiplied by 0.1 in order to relate the 1:9 dilution tested to the SPP of the whole drilling fluid. 20 ------- TABLE 9. Results of acute toxicity tests with mysids (Mysidopsis bahia) and two generic drilling fluids containing mineral oil. The tests were conducted at U.S. EPA, Gulf Breeze, Florida, during September-October 1983. All LCSO's and 95% confidence limits were calculated by the moving average method. Drilling Fluid 2-01 2-05 2-10 8-01 8-05 8-10 Range-finding Test (median effect) >10 <50% SPP* >1 <10% SPP <1% SPP >1 <10% SPP >1 <10% SPP <1% SPP Definitive Test (96-h LC50 4 95% CL) 13.5% SPP (11.1-16.9) 1.8% SPP5 (1.4-2.2) 0.49% SPP (0.39-0.62) 7.1% SPP (5.7-9.0) 0.90% SPP (0.74-1.1) 0.76% SPPC (0.63-0.87) Positive Control (96-h LC50 4 95% CL) 5.3 ppn (4.6-6.1) 7.1 ppmc (6.4-7.9) 7.1 ppmc (6.4-7.9) 4.3 ppm (3.7-4.9) 5.6 ppmc (5.0-6.4) 5.3 ppm (4.6-6.1) a The suspended particulate phase (SPP) was prepared by mixing 1 part drilling fluid with 9 parts seawater. Therefore, these values should be multiplied by 0.1 in order to relate the 1:9 dilution tested to the SPP of the whole drilling fluid. b Corrected for 13% control mortality. c Corrected for 15% control mortality. 21 ------- TABLE 10. Results of three acute toxicity tests conducted with mysids (Mysidopsis bahia) and generic drilling fluid #8-05 (5% mineral oil) at U.S. EPA, Gulf Breeze, Florida. Mortality data are given as percentages. Exposure Concentration (frSPt^) Test Control 0.5 0.625 1.0 1.25 2.0 2.5 4.0 5.0 8.0 10 5O 100 Hange-finding 0 - -20%-- -- -- 100% 100% 100% Definitive til 17% - 40% 63% 72% - 95% - 100% - - Definitive *2 1UX 30% - 48% - 88% - 95% - 100% - - * __ a The sus|*-nded particulute phase (SPP) was prepared by mixing 1 part drilling fluid with 9 parts seawater. Therefore, these values should be multiplied by 0.1 in order to relate the 1:9 dilution tested to the SPP of the whole drilling fluid. ro ro ------- APPENDIX A CHEMICAL AND PHYSICAL CHARACTERISTICS OP THE MINERAL OIL USED IN THE LABORATORY-PREPARED GENERIC DRILLING FLUID TESTS 1. Mineral oil analysis reported by IMOO Services, drilling fluid #2 Boiling range (IBP-FBP) Vapor pressure Vapor density Solubility in water 9100°F Specific gravity Percent volatile by volume (%) Evaporation rate Flash point (Pensky-Martens) 500-610°P 0.008 >8 30 ppn 0.845 100 <0.01 255° P 2. Mineral oil analysis reported by Dowell, drilling fluid #8 op op ppn Chemical name Chemical family Formula Boiling point, IBP, FBP, Vapor pressure (mm Hg) , 20°C Vapor density (air § 1) Solubility in water § 100° P, Specific gravity (water » 1) Percent volatile by volume, % Evaporation rate (n-Butyl acetate Appearance and odor Gravity, °API at 60° F Flash point, COC, °F Pour point, °P Color, ASTM D 1500, Saybolt color Viscosity. cSt at 40°C SSU at 100 °P 1) Paraffin - base oil Petroleum hydrocarbon Complex misture of petroleum hydrocarbons 500 610 0.008 >8 30 0.845 100; evaporates slowly at 100°F <0.01 Clear light color. Slight kerosenic odor 35.8 258 (Pensky - Martens 255°F) 5 28 4.2 41.0 This oil is stable, but strong oxidants such as liquid chlorine, concentrated oxygen, and sodium or calcium hypochlorite should be avoided. 23 ------- APPENDIX B MORTALITY DATA Test Drilling SPP* Test Location Fluid Concentration Gulf Breeze #1 Control 1% 2% 3% 4% 5% #2 Control 10% 30% 50% 70% 90% #3 Control 10% 20% 30% 40% 50% Mysids Exposed 60 60 60 60 60 60 60 60 - 60 60 60 40 60 60 60 60 60 60 Mysids Killed 3 11 11 25 48 60 4 3 9 9 49 39 6 15 39 39 45 53 Percentage Mortality 5 18 18 42 80 100 7 5 15 15 82 98 10 25 65 65 75 88 (continued) a The suspended particulate phase (SPP) was prepared by mixing 1 part drilling fluid with 9 parts seawtaer. Therefore, these values should be multiplied by 0.1 in order to relate the 1:9 dilution tested to the SPP of the whole drilling fluid. 24 ------- APPENDIX B, continued. Test Drilling Location Fluid Gulf Breeze #7 #9 Narragansett #1 Sppa Test Concentration Control 20% 40% 60% 80% 100% Control 10% 20% 30% 40% 50% Control 1.0% 2.5% 5.0% 7.5% 10% Mysids Exposed 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 Mysids Killed 2 13 21 21 37 41 1 0 11 31 42 56 1 1 5 5 60 HO Percentage Mortality 3 22 35 35 62 68 2 0 18 52 70 93 2 2 8 100 LOO 100 (continued) 25 ------- APPENDIX B, continued. Test Drilling SPP* Test Location Fluid Concentration Gulf Breeze #2-01 Control 2.5% 5% 10% 20% 40% #2-05 Control 1% 2% 4% 3% 16% #2-10 Control 0.25% 0.5% 1% 2% 4% Mysids Exposed 60 60 60 60 60 60 60 60 60 60 60 60 60 GO 60 60 60 60 Mysids Killed 1 12 16 21 26 56 8 22 37 50 57 60 4 17 29 46 49 60 Percentage Mortality 2 20 27 35 43 93 13 37 ' 62 83 95 100 7 28 48 77 32 100 26 ------- APPENDIX Bf continued. Test Drilling SPP* Test Location Fluid Concentration Gulf Breeze #8-01 Control 1.9% 3.2% 5.4% 9% 15% i^S-05 Control 0.5% 1% 2% 4% 8% #8-10 Control 0.5% 1% 2% 4% 8% Mysids Exposed 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 tfO 60 60 Mysids Killed 5 6 15 28 31 44 6 18 29 53 57 60 9 23 43 57 60 60 Percentage Mortality 8 10 25 47 52 73 10 30 48 88 95 100 15 38 72 95 100 100 ------- |