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January 23, 1991 DRAFT DO NOT CITE OR QUOTE REVIEW AND COMPARISON OF DETERMINING ACCEPTABLE AMBIENT AIR CONCENTRATIONS FOR VINYL CHLORIDE BASED ON CARCINOGENICITY IN TWO EPA REPORTS There are two recent EPA documents in which estimates were derived for ql* values for vinyl chloride. In the first document (Health Effects Assessment for Vinyl Chloride, EPA, 1984, Office of Health and Environmental Assessment, EPA/540/1-86-036) the animal ql* was given as 4.23xl0"3 (mg/kg/day) and the human ql* was given as 2.5xl0"2(mg/kg/day)"1 (see Appendix 1 for determination of animal ql* value using GL0BAL86). Inhalation studies in rats were used and total tumors were used as the toxicological end point. This ql* value can be converted to units of ppm"1 or (ug/m3)"1 as follows by employing the same conversion factors used by EPA in converting animal exposures in ppm to human equivalent exposures in mg/kg/day: area between [(l/(70-kg human/.35 kg rat))1/3] * 2.5xl0"2 4.27xl0"3 (mg/kg/day) "1 4.27xl0"3/ .35 kg rat = 1.22X10"2 (mg/day)"1 .233 m3/d * 1.22X10"2 = 2.72X10"3 (mg/m3)"1 or' 2.72xl0"6 (ug/m3)"1 or 2.56X103 (ug/m3*ppm)*2.72xl0"6 (ug/m3)"1 = 6.96xl0"3 ppm"1 (EPA84 calculation was 6.80xl0"3 ppm"1) It was assumed that all the vinyl chloride inhaled was absorbed into systemic circulation. This is a conservative estimate. In a more recent update -(Health and Environmental Effects Profile for Chloroethene, EPA, 1985, Environmental Criteria and Assessment Office ECA0-Cinn-P155) the rat ql* was determined to be 5.04X10"2 (mg/kg/day) (see Appendix 2 for determination of the rat ql* value using GLOBAL86) and the human ql* was determined to be 2.95x10" (mg/kg/day)"1. Animal studies from the same investigator were used as in the EPA 1984 report; instead of using total tumor incidence, however, angiosarcomas of the liver were used as the only toxicological end point. Corrections to the dose were made since the observation period was extended after exposure stopped and an assumption was made that only 50% of the inhaled vinyl chloride was being absorbed. By using the same conversion factors above and correcting for % uptake the following inhalation ql* was determined. A [(1/(70/.35))1/3]*2.95x10-1 (mg/kg/d)"1 - 5.05xl0'2 (mg/kg/d)"1 15.05xl0"2 (mg/kg/d)-1/.35kg]*.223 m3/d - 3.22X10"2 (mg/m3)"1 or 3.22X10"5 (ug/m3)"1 3. in this assessment EPA assumed that only 50% of the vinyl chloride was absorbed through the lungs. To correct for this the ql* value has to be multiplied by .5. (.5)*3.22xl0"5 (ug/m3)"1 = 1.61xl0"5 (ug/m3)'1 or 4.12xl0"2 ppm"1 The state of Mississippi is recommending a ql* value of 4.2X10"5 (ug/m3)"1. This value is derived from the more recent EPA report just described from the ql* value of 2.95X10"1 (mg/kg/d)"1. This number is 2.6-fold greater than the number calculated above (1.61 x0"5). Mississippi derived their number as follows. [2.95x10"1 (mg/kg/d)"1]*(.5) *(20 m3/d)*(10-3mg/ug)/70 kg 4.21X10"5 (ug/m3)'1 This calculation is incorrect, since the same conversion factors used by EPA to convert experimental levels (ppm) to human exposure equivalents (mg/kg/day) were not used by the state of Mississippi to back--calculate from (mg/kg/day) to ppm or ug/m3. Figure 1 illustrates the relationship between liver angiosarcoma and vinyl chloride exposure in rats. No dose-response relationship is obvious. Furthermore, EPA did not use all the data in determining the ql* value. It only selected data points 0, .172, .344 and .86 mg/kg/day. There was no rationale provided why other data points were omitted. In addition, the data points 2 VAB.0001125518 are not even taken from the same experiment. For example, data points .344 and .86 were from Maltoni et al. experiment BT15 and data point 1.719 was taken from Maltoni et al. experiment BT1. Therefore, the manner in which the ql* value was calculated is scientifically incorrect and meaningless. In the 1985 report the length of the experiment was reported to be up to 1029 days, whereas the exposure period to vinyl chloride was for 365 days. In the transformation of experimental doses to human equivalent doses an adjustment factor of 365/1029 was used. From a biological sense this dose--averaging approach may not be appropriate. The actual time to tumor data needs to be obtained in order to make the appropriate adjustments to dose. The first ql* value established by EPA in 1984 was based on total tumors rather than liver angiosarcomas. Although in some instances total tumors may not provide the most sensitive assessment of cancer risk, the data as shown in figure 2 do show a linear dose response relationship up to 239.1 mg/kg/day. Therefore, these data provide a much better data base to determine a human ql* value, than the data base given in the EPA 1985 report. EPA's Office of Health and Environmental Assessment often has contractors provide health profiles and reports on various chemicals. These documents are used primarily as guidance to provide available information on the toxicity of various environmental agents and to provide the agency scientists and regulators with initial data to determine what chemicals potentially should take greater priority in being regulated. Although these documents have undergone some peer review within EPA they have not undergone the extensive scientific peer review that is usually necessary to support program office regulations. The more recent 1985 EPA report entitled "Health and Environmental Effects Profile for Chloroethene," which is being used by the State of Mississippi, is a first draft report and has the disclaimer that it is "for review purposes only and does not constitute Agency policy." Discussions with EPA scientists in the Cancer Assessment Group revealed that they are aware of the deficiencies in the approach taken in the 1985 EPA report for calculating a ql* value for vinyl chloride and that additional evaluations of the data base are necessary to derive a more scientifically sound quantitative risk assessment. The state of Mississippi elected to use a unit risk factor of 2.95X10"1 (mg/kg/day) "r taken from an EPA report "Health and3 3 VAB.0001125519 A Environmental Effects Profile for Chloroethene11 September 1985. From this value they converted the units to obtain a ql* value of 4.21x10-5 ug/m3. This value is not appropriate to use to set acceptable ambient exposure levels to vinyl chloride for the following reasons: 1. The conversion from mg/kg/day to ug/m3 was done incorrectly (see above) . The correct conversion would reduce the unit risk by a factor of 2.6. 2. The calculation was performed using a ql* value that EPA has not endorsed. This is stated in the disclaimer in the 1985 document 3. The data used in calculating the ql* value in the 1985 EPA report are not of sufficient quality to determine a ql* value a. There is no dose-response relationship. b. Results from different experiments were pooled in order to get a dose response relationship without any scientific rationale provided. c. Only certain data points were selected for determining the unit risk without any scientific rationale provided. d. Two of the data points available in the original Maltoni et al. paper were not included in the 1985 EPA report. No scientific rationale was provided. 4. Vinyl chloride is known to require metabolic activation to the proximate carcinogen. These pharmacokinetic considerations were not incorporated into the dose--response data used in determining the unit risk determination in the 1985 EPA report.5 5. Many other studies are available than Maltoni et al. to estimate the carcinogenic risk of vinyl chloride. These other studies should be assessed, and pharmacokinetic/biologically based models should be considered to estimate more accurately the human carcinogenic risk of exposure to vinyl chloride gas. f the unit risk presented in the 1985 EPA report "Health and Environmental Effects Profile for Chloroethene establish acceptable ambient levels vinyl the air is not scientifically justifiable because of VAB.0001125520 A the misuse of the data, lack of critical peer review of the methods employed in the report, and insufficient use of critical data pertinent in considering the carcinogenic risk of vinyl chloride Until a more scientifically sound risk assessment is performed the former gl* value of 2.72xl0"6 (ug/m3)"1 from the 1984 EPA report entitled "Health Effects Assessment for Vinyl Chloride" should be used to estimate cancer risk for vinyl chloride in the air. Although there are also deficiencies in the data on which this ql* value is based, a solid dose-response relationship for total tumors (figure 2) was used to estimate risk. VAB.0001125521 APPENDIX 1 GLOBAL 86 (MAY 1986) BY RICHARD B. HOWE AND CYNTHIA VAN LANDINGHAM CLEMENT ASSOCIATES, 1201 GAINES STREET RUSTON, LA 71270 (318) 255-4800 INC A vinyl chloride: data taken from EPA 1984 report (total tumors) POLYNOMIAL DEGREE SELECTED BY PROGRAM, (POLY-DEGREE*0) CHI-SQUARE TEST USED IN SELECTION GROUP DOSE ^RESPONSES OBSERVED/#ANIMALS 1 .000000 2 4.90000 3 23.9000 4 47.8000 5 239.100 6/ 58 10/ 59 16/ 59 22/ 59 32/ 59 CHI-SQUARE GOODNESS OF FIT STATISTIC IS ^RESPONSES PREDICTED 9.81 10.69 13.35 16.50 34.98 5.6876 P-VALUE FOR THE CHI-SQ TEST WITH 3 DEGREES OF FREEDOM IS .1278379359 FORM OF PROBABILITY FUNCTION: P(DOSE) = 1 - exp( -Q0 - Q1 * D - Q2 * DA2 ) MAXIMUM LIKELIHOOD ESTIMATES OF DOSE COEFFICIENTS Q( 0) = Q( 1) * Q( 2) = .185324445807 2983355597998E-03 .000000000000 MAXIMUM VALUE OF THE LOG-LIKELIHOOD IS -163.144925015 CALCULATIONS ARE BASED UPON EXTRA RISK GLOBAL 86 UPPER CONFIDENCE LIMITS ON RISK FOR FIXED DOSE DOSE 1.0000 MLE RISK 2.97891E--03 NORMAL COMPLETION! UPPER BOUND ON RISK CONFIDENCE COEFFICIENTS FOR LIMIT SIZE CONFIDENCE LIMIT -03 95.0% Q( 0) - .15535 Q( 1) - 423149E--03 Q( 2) - .00000 VAB.0001125522 APPENDIX 2 GLOBAL 86 (MAY 1986) BY RICHARD B. HOWE AND CYNTHIA VAN LANDINGHAM CLEMENT ASSOCIATES, INC 1201 GAINES STREET RUSTON, LA 71270 (318) 255-4800 A vinyl chloride: data taken from EPA 1985 report (1iver angiosarcomas) POLYNOMIAL DEGREE SELECTED BY PROGRAM. (POLY-DEGREE-O) CHI-SQUARE TEST USED IN SELECTION GROUP 1 2 3 4 DOSE .000000 .344000 .860000 1.71900 #RESPONSES OBSERVED/#ANIMALS 0/363 1/119 5/120 If 60 #RESPONSES PREDICTED .00 1.17 2.92 2.89 CHI-SQUARE GOODNESS OF FIT STATISTIC IS 2.8312 P-VALUE FOR THE CHI-SQ TEST WITH 2 DEGREES OF FREEDOM IS .2427793524 FORM OF PROBABILITY FUNCTION: P(DOSE) * 1 - exp( -Q0 - Q1 * D - Q2 * DA2 ) MAXIMUM LIKELIHOOD ESTIMATES OF DOSE COEFFICIENTS Q( 0) = Q( 1) = Q( 2) - .000000000000 2867931930907E--02 .000000000000 MAXIMUM VAIAJE OF THE LOG-LIKELIHOOD IS -33.1407703774 CALCULATIONS ARE BASED UPON EXTRA RISK GLOBAL 86 UPPER CONFIDENCE LIMITS ON RISK FOR FIXED DOSE DOSE 1.0000 MLE RISK 282720E--02 NORMAL COMPLETION! UPPER BOUND ON RISK 4.91334E--02 CONFIDENCE LIMIT SIZE 95.0% COEFFICIENTS FOR CONFIDENCE LIMIT Q( 0) - Q( l) -> Q( 2) - .00000 5.03816E-02 .00000 r VAB.0001125523 tumor incidence A Figure 1 EPA85 (liver angiosarcomas) 0.06 0.05 0.04 0.03 0.02 I 0.01 0 0 0.0344 0.172 0.344 0.86 1.719 mg/kg/day 3.438 5.158 6.878 8.596 VAB.0001125524 9300 In Highway, Fairfax, Virginia 22031 (703) 934-3500 __________(703) 934-3278 FAX__________ Fatcslmllo Mwiigi Cow Shoot VAB.0001125525 November 23, 1990 DRAFT DO NOT SITE OR QUOTE Review and Comparison of Acceptable Ambient Air Concentrations for Vinyl Chloride Based on Carcinogenicity There are two recent SPA documents in which estimates were derived for ql* values for vinyl chloride. In the first document (Health Effects Assessment for Vinyl Chloride, EPA, 1984, Office of Health and Environmental Assessment, EPA/540/1-86-036) the human ql* was determined to be 2 .SxlO^Cmg/kg/dey)"1. Inhalation studies in rats were used and total tumors were used as the toxicological endpoint. This ql* value can be converted to units of ppm-1 or (ug/m3)"1 as follows: 1. correction for surface area between humans and rats [ (l/(70kg human/.35 kg rat))1/8] * 2.5xl0'a - 4.27 x 10'* (mg/kg/day)'1 2. adjustment for body weight of rat 4,27xl0'3/. 35 kg rat - 1.22 x 10'2 (mg/day)"1 3. adjustment for breathing rates of rets .233 m3/d * 1.22 x 10"a 2.72 x 10"a (mg/m3)'1 or 2.56 x 103 (ug/m3*ppm)*2.72 x 10"4 (ug/m3)'1 6,96 x 10'3 ppm"1 In a more recent update (Health and Environmental Effects Profile for Chloroethene, EPA, 1985, Environmental Criteria and Assessment Office 1GA0Cinn-Pl55) the human ql* was determined to be 2,95 x 10"1 (mg/kg/day)"1. same animal studies were used, only Instead of using total tumor Incidence, just angiosarcomas of the liver were used as the toxicological endpoint. Also, corrections to the dose were mads since the observation period was extended after exposure stopped end an assumption was made that only SOX of the Inhaled vinyl chloride was being absorbed. By using the seme conversion factors above end correcting for X uptake the following inhalation ql* wee determined. 1. correction for surface area between humans and rats [(l/(70/.33))1/#]*2,95 x 10'1 (mg/kg/d)'1 - 5.05 x 10~* (mg/kg/d) VAB.0001125526 i 2, adjustment for body weight and breathing rate of rats [5.05 x 10'2 (mg/kg/d)**1/-35kg]*.223 m3/d - 3.22 x 10"2 (mg/m3)'1 or 3.22 x IQ'5 (ug/ma) 3. In this assessment EPA assumed that only 50% of the vinyl chloride was absorbed through the lungs. To correct for this the ql* value has't to be multiplied by .5. (. 5)*3,22 x 10"s <ug/maj\)-i -MHMMNHEW (\ugO//m3)/ '1 or 4.12 x 10`2 i The state of Mississippi is recommending a ql* value of 4.2 x 10"5 (ug/m3)'1. This value is derived from the more recent EPA report just described from the ql* value of 2.95 x 10"1 (mg/kg/d)'1. As you can see this number is 2.6 fold greater than the number calculated above (1.61 x 10'3). Mississippi derived their number as follows. 1. [2.95 x 10'1 (mg/kg/d)"1]*( .5)*<20 m3/d)*(10-3mg/ug)/70 kg - 4,21 x 10"5 (ug/m3)"1 This calculation is wrong, since they did not back calculate to the original experimental air levels of vinyl chloride. The Toxic Substances Control Program in the California Department of Health Services is currently recommending a unit risk of 7.14 x lO*2 (mg/kg/d)'1 (personal communication. Dr. John Brantner, staff toxicologist, California Dapartment of Health Services). By using the earns calculation procedure that Mississippi used and using California's assumption of 42X retention of vinyl chloride by the lungs, this converts to s ql* of 8,57 x 10"* (ug/m3)"1 (I was unable to get enough data to perform the correct calculations which would result in a lower ql*). The California Department of Health Services recommends this unit risk estimate to determine acceptable vinyl chloride levels at toxic waste sites. However, The California Air Resources Board is considering promolgating a ql* value of 20 x 10"5 ppb'1 (7.81 x 10"5 (ug/m3)'1)/ I do not have the information to determine which animal studies were used in this determination. However, the use of this value would result in the lowest acceptable ambient air concentration. The following table provides the ql* values currently used by various states in setting smblent air concentrations considered to provide an acceptable cancer risk of 10"*. State unit risk (ql*) (ug/mm3)"1 acceptable exposure (cancer risk of 10"*) \ VAB.0001125527 A KS .26 x 10"* 3.85 ug/m3 KS-KC MA HI NC NY PA-Phil TX VT EPA (old) EPA (now) GA (toxic Subatancea Control Program) CA (proposed by Air Reeourcea Board) MS a 4,1 2.6 2.5 2.6 2.5 0.16 0.10 5.00 2.72 e 16.1 8.57 78.1 42 m .24 .38 .40 .38 .40 6.25 10. .20 .37 .06 .11 .01 .02 At you can aaa from this table many of the states are using EPA1 a old ql* value for determining level a not to exceed a cancer risk of 10~(. If one uaea the new EPA ql* the acceptable levels would have to be reduced by a factor of 6 over the old estimates. In setting the new ql*, however, the data used looks very supielous, Por example, ql* was calculated using these data points from the rat inhalation studies; * transformed dose corrected for average dose amount abaorbad Incidence (liver angiosarcoma) No. responding/No. tested or examined 0.344 ng/kg/dy 1/119 0.860 S/120 1.719 1/60 3.438 1/120 VAB.0001125528 f wm T Distribution J. R. Ganc January 7, 1991 AIR DISPERSION MODELING OF VCM EMISSIONS An air dispersion model developed by the EPA was used to determine the concentration of VCM emissions in the vicinity of the Aberdeen plant for current and hypothetical operating conditions. This model was also used to determine the most effective ways to lower VCM concentrations to comply with current and future air permits. It was shown that lowering the VCM concentration of our slurry not lower the fenceline concentration linearly. a significant of the concentration is made up of fugitive emissions from the sphere. Although the sphere does not emit an overwhelming weight of VCM per year, its closeness to the west fenceline of the plant means its emissions are still concentrated when they reach the fenceline. Lowering the slurry concentration does lower the VCM concentrations from our plant almost linearly, however. Because of the location of the sphere, purchasing or otherwise insuring land on the northwest side of the plant is not used for residential purposes lowers our boundary VCM concentrations significantly. Minor alterations of the characteristics of the stacks will have some, but little effect on the fenceline concentrations. There is still some controversy upon which unit risk factor the state will use when we apply for our newest air permit, and as such, a comprehensive strategy for obtaining this permit cannot be determined at thiB time. Joseph R. Ganc cc: Aberdeen: Houston: Austin: RWS, JCL, DP DCS, WLM, JDO, DLC SCH, RBN, FJG mmmmm WNHU IMHIII >111"HUM i wmrtmmmm mf ItMlIIMlMiPMMIMMmiMVIBMmiNNM UNNPHMl VAB.0001125529 MHMNWIWff Joseph C. Ledvina To A0<& j * JO ^-sfc'V'7 r-iS) Art# fr / F i VAB.0001125530 4 A *sOtCM (. KCLLCR JCMOMC HCCHNAN WILLIAM M. lOMMOANt, UL MALCOLM O. MaAAOTMUN WATNC V, *LAC* TCdifNCt O. JOMCS mamtim W. SBmCOV'CI johk a. cloaks CaMOU C- MAttara MAAV MAMTMA mmmamama MfCMACL r. momomc manm roa OfNt JOHN a. MCMAftOO jomm s.susccm : arrot l- m ** c*us CnAtSTlHC M. S'LL MKLVIM a. MOJCM SHtWUT i. fUJIMOte LAMTMCMCC a. MALPOIM aalam a. tmwQMi rrca a. tuuift C. OOUOLAa uA*eCTT WOT ADM ITT CO *W DC. S MCI LA A. MILLAft AATIMCA J. MUM oraicDooMmcitM. maidmugo*, urn* I ll LAW OFFICES Keller -and Heckman 1150 17TM STREET, N.W. SUITS lOOO WASHINGTON. D.C. 80030 (802) 50-5000 T %. iyW December 28, 1990 aciCNTirtc staff M*M8t a. OWLCA, Mm. p. CMAALCSV aWMR.ai,0. O^pr 4^MATMCWa, Pm. a JOOO MOOOCOMAM. Pm* O, MU* HUTMiAC FOLCT , JUSTtN c MCU. Am* O* jAMcrrc moul am. o. TCVCCOHMUlHCATlOMa IMOttCM CMAAlU r. TUAHCH TCLCa 49 oaaai mceoptca WOt>tPT|| caplc Aooacaa -kclmam- MTlCp OMCCT DIAL HUMACA (202) 956-5641 Hr. David Hughes Louisiana Department of Environmental Quality Office of Air Quality and Radiation Protection Enforcement and Regulatory Compliance Division 323 Laurel street commerce Building, Room 620 Baton Rouger Louisiana 70804 Re: VI Comments Concerning a Proposed Rule to Amend the Air Quality Regulations, LAC 33:111, Chapter 51 Subchapters A, c, E, F, J, M, and V, and LAC 33:111. 6511 and 6523 (LOO HUMBER AQ12) Dear Hr Hughes: Keller and Hackman is pleased to submit comments on behalf of the Vinyl Institute (VI), a division of the Society of the Plastics imiiistmy^ Inc. (SPI)I/ concerning the Louisiana 1,1....... 11 TP WH^I^PWSMMWMMMM^MMPMMe !K ' 1/ SPI is a 2,000 member not-for-profit trade organisation representation all segments of the plastics industry in the United States. The Society's members include processors and manufacturers of plastics and plastic products, suppliers of raw material, precassors and converters of plastic resins and manufacturers ofacoaeeory equipment for the plastic industry. Foundsd in 1937, itl is the major national trade association of the plastics industry. Hembers of the Vinyl Institute include the BF Goodrich company, Borden Chemicals and Plastics Xndustriss, CartainTeed Corporation# The Pom Chemical Company, Georgia Gulf Corporation, Occidental Chemical corporation, PPG Industries, VAB.0001125531 mm V mmmm mmmmrn^ m m Hr. David Hughes December 28, 1990 Page 2 * Keller and Heckman Department of Environmental Quality's (DEQ) proposed Comprehensive Toxic Air Pollutant Emission Control Program (Proposed Rule).2/ As an initial matter, the vx requests that the period for submission of comments be extended because the VX has not had sufficient time to poll its members concerning an appropriate unit risk factor for vinyl chloride*: DEQ did not publish notice concerning the proposed rule until. November 28, 1990, and required interested parties to submit comments no later than December 27, 1990. fi. La. Reg. Vol. 16, No. ll (Nov. 20, 1990). The short comment period provided by DEQ did not permit the VX to prepare comprehensive comments. The vx will summit additional comments, after polling its members, which will recommend an appropriate unit risk factor based on existing toxicological data and address other issues. Xn the present comments, the VX will address the proposed ambient air standard for vinyl chloride of 1.19 jjg/m3. LAC 33: XXX .5105 at Table 51.2. As will be discussed more fully below, this ambient air standard is not supported by the administrative record in this rulemaking. Xn fast,I unit risk factors for vinyl chloride listed in the administrative rsfcord result in significantly higher ambient air standards than 1.19 Mg/m3. Moreover, DEQ did not provide sufficient notice .concerning the state's development of a unit risk factor and apbient air standard for vinyl chloride to allow affected parties to adequately comment on these values. A. Regulatory Background Act 184 requires the Secretary of DEQ to prepare an initial list of loo toxic air pollutants (TIPs) proposed tot regulation under provisions of the Act. R . S 30:2060(a)(1). Vinyl chloride appeared on the proposed list of 10Q TIPs to be regulated under Act 19*4. see.f Luaa. RHI eaorr*. Vol. 15, p 73 (January 20, 1990) DEQ a "Development Inc., PW Resins, Sliintech, Inc., and Vista Chemical. Members of the vinyl institute account for approximately 82% of the domestic production of vinyl chloride and 63% of the domestic production of polyvinyl chloride. 2/ The Proposed Rule amends the Air Quality Regulations at LA ADMIN* Code title 33, Part XXX, Chapter 51, Subdhapters A, C, E, F, J, M, and V and LAC 33: III*6511 and 6523 (AQ12). VAB.0001125532 Mr* David Hu^hts Deceaber 28, 1990 A Keileh ahd Hsckman Document* on Kerch 27, 1980, which vaa designed to provide details on the intonation and employed in developing the Act 184,i/The SAHA beregulated under hlouAg: and &. Aofc m mea.^ - um'.*AxjW&aLEaiP,f^S. -aojari the liet^dlt itO s4 ;' Mth^Le-ie':MpZr'ZinKcZdSLp*. fllfti 0|eOeii&T'" |'iL"v :^L;-: i. eS end ever was then reduced reasonable expftcted to he dir in Louisiana e&, D.D. at 4. Then, four criteria were used :< -u %TT whether the resaining Substances be ii These emission'`levels, human 'V 1. ^ or o4- 4. -1;^ ,:-' -1 in the D.D* at v From the the list was narrowed concern the concl 11.5/ e classes of substances, Document concerning on a report by of Louisiana state D.D. at 7 and On November 20, 1990, DEQ provided public notice regarding the proposed regulations for the " "'^ ""'" including vinyl chloride* compiledprevlouSly. An, air standard of i 19 Mg/ar is proposed for vinyl chloride* 111. 5105 at Table 51.2. NO: owner or ooeriitor of cause., allow, ' or: penait. y yi M'w* 11 X,*IL 4 v1 ******* tm d* liei ill' en ieil& **mk of vinyl property to ,-rl -air a source may to cause off the source1s Id. at $ 5105 D.2. 2/ Louisiana Department of Air Quality and Nuclear Energy, Quality, Office of (March 27, 1990). f D.D. refers to the DEQ Development Document. 2/ B. Shane and s. Gardner, Assessment of Air Toxics Released in Louisiana in 1987, (1989) Louisiana State University. Hersinafter, this report will be referred to as the Shahs and Gardner Report. VAB.0001125533 Mr. David Hughes December 28, 1990 Page 4 AND Tfea Miinistrative Record Does Mot support deq's Mmbtest Air Standard voir fiiyl chloride support unit title Gardner the and .-i I <- First, it seiw il^rgprists to discuss the method by which DDQ calculates aRbient air standards, DBQnotes in the proposed rule standards are Based on unit risk factors and a of one in ten thousand. see LAC 33:111.5105 at Table 51.2 (explanatory notes). Ho unit risk factors are listed |n tbs* proposed rule, but they can be found ih the DOC t. For axamp unit risk factor for benzene is listed in bo 4 tb. D.v,lopn.nt Decumant as St 72. and D.jp. at 34. risk' of. 1x10"* divided. by. benzene's unit risk , the ambient air standard of 12 Mg/m* results, das# LAC 33:111.5105 at Table 51.2. Of 2.6X10 2.5x10 (mg this unit r results. vinyl ch|oridd standard for a unit risk factor and Gardner at derived from a 1984 of risk is divided by of 385 pg/mr and,' Gardner^ hk* 1 ' IS ^Er L lfc' a1 factor for m 'i *j to calcglffe the afbient air in the proposed The Development Document 4.2xl0~5 Mg/m3 for vinyl chloride (D.D. at 34.) which is significantly greater than the Shane and Gardner value, Our review of EPA studies of vinyl chloride indicates that the . I I..'*'. R rk >f \ J Agency for Toxic Substances and Disease Control Registry, Toxicological Profile for vinyl chloride, 1989, U.S. Public Health Service, at 81. VMM wmmmmmmmmmmm mm m VAB. Mr David Hughes Decamber 28, 1990 Pags 5 Keixeh and Heckman Development Document unit risk factor for vinyl chlorida is derived free anEFA unit risk feator basedonorel exposure.!/ it islnappraprlate tier. DEG to us* tt--b gn^Try unit risk feotor of 4.2x10* pm/* develop h embient air standard fCr vlnyl ohlerlAa siaoe the unit risk factor is teased oral rather then inhalet ton ^sesodtere. Moareoverr the DevelopmentDocumsnt unit riah kvPwtWe^Bo^tiHe9NoEgF '.JBftoSpBrT vinyl chloride does not produce the ambient air standard for vinyl chlorida listed in the proposed rule. He moet reeeat unit rink factor for vinyl chloride inhalation which the VI is aware of is 4 1x10'* ;ig/ir. phis unit risk factor, which appears in a 1989 SPA Office of Air Quality Planning and Standards external review draft,&J results in an ambient air standard of 24 . 2 pg/m. /ig/m3 The anhient air standard for vinyl chloride not based on any unit risk factor in the 1.19 administrative record for this rulemaking since neither the Shane and Gardner or the Development Document unit risk fac for vinyl chloride was used. Furthermore, the Document unit risk^factor cannot be> turned-since it iii based on oral exposure. The wit risk factor necessary to generat DEQ's ambient air standard for vinyl chloride is 8.4xio^ ng/mz This unit risk factor does not appear anywhere in the administrative record or in EPA documents concerning vinyl chloride. Consequently, the administrative record does not support DBQ's proposed ambient air standard for vinyl chloride C Procedural Requiremeate 1 DSQ Must Provide Notice and comment Mlemakixfeg procedures The State of Louisiana must conduct notice and comment rulemaking on the issue of how DSQ derives the unit risk facto and ambient air standard which is the basis for the regulation 2/ U.S. Environmental Protection Agency Office of Research and Development, office of Health and Env Assessment Health Effects Asssssment Summary Tabl First Quarter FY89 (Jan. 1989); cited in U.S. ^ - Agency, office of Risk From Outdoor Exposure to Air Tokios (Sep. at 2- / U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Canter Risk From Outdoor Exposure to Air Toxics (Sep. 1989) at 2*21. VAB.0001125535 Mr. David Hughes December 28, 1990 Page 6 Keller and Heckman of emissions of vinyl chloride. DEQ cannot rely on unit risk factors developed through non-rulemaking procedures by spa or other rase Isimirrcheiise asths basis for regulating 'vinyl chlerids esissifinm JBSfers siihmtt~1~ H| KMb lt ilik factor and ths hhlent air standard deri therefrom to tbs notics %na prscedaSss established by Louisiana lav and reqpiapd Dy^th* Dus Itrnosss ri aiiss of ths 8.8.,' Const, amend and XIV DEQ's establishment of a unit risk factor and ambient air standard for vinyl chloride is a rule as that term is declined in the Louisiana Administrative Procedure Act. R.S. 49:981(6) The Act defines #rule*1 as: [A]n agency statement,. guide or requirement fo: conduct or action .. which has general applicability and the effect of implementing o interpreting substantive lev or policy, or which prescribes the procedure or practice requirement* of the agency. Sae-R.H. DSD * e establishment of a unit risk factor end. ambient air. standard for viny chloride clearly falls within the def ini "rule" since these values regulate vinyl chloride emissions and thereby implement 184. The Louisiana Administrativa Procedures Act requires notice and comment rulemaking procedures befors an agency adopts a rule. Sea# R.S. 49:953. Consequently, DEQ must submit the unit risk factor and the ambient air standard for vinyl chloride to the notice and comment rulemaking procedures required by Louisiana law before relying on these values as a basis for regulating vinyl chloride. Incorporating an EPA unit risk factor by referenoo will not fulfill Louisiana's notice and comment requirements since such incorporation will fail to present the basis upon which the unit risk factor rests. The affected public must be given the opportunity to comment on the unit risk factor for vinyl chlorida used by DEQ and the basis for its development. In large part, the statutory mandates requiring notice and comment rulemaking procedures stem from the Due Process Clause of the united States Constitution. U.S. Const, amend. V and XIV. Procedural due process means that procedure which is "due" in light of the circumstances and interests involved. 424 U.S. 319, 334-335 (1976). It requires VAB.0001125536 Mr. David Hughas December 28, 1990 Page 7 / (* Kelleh and Heckman Here, Louisiana lav requires that DEQ provide legally adequate notice and an opportunity to comment on bSQ' establishaent of a unit risk factor and aabient air standard for vinyl chloride. However; even without these provisions, DEQ is constitutionally required to provide notice and permit a real opportunity to present nts that inform the state1 s iy make a filial determination. Ir^ i:. a. are absolutely of affected that it is relying on an which did no result from a to these values :;i thin should on formal public rules,akin 42 u.s.e. en pursuant; to the Clean: AirJ Act. unit risk factors could be legitimately used by DEQ because: (1) notice and comment should develop the effects Sdurek^SS' usedby EPA and (2) EPA t!riik factors basod on'inhalation i under the under If EPA had gone through notice and comment rulemaking procedures concerning a unit risk factor for vinyl chloride, then Louisiana's obligation to implement similar procedures would ba reduced. The need fear notice and commant on any unit risk factor for vin^l chloride is further emphasized by the fact that theirs is no unit risk factor for vinyl chloride on EPA's Integrated System (IRIS) database, indicating that there is no consensus within EPA as to a unit risk factor for vinVl ehlofide. VAB.0001125537 Mr. David Hughes December 28, 1990 Page 8 Keller and Heckman 2. Substantial Evidence Requirement 1 k*. . i> dbq cannot establ an ambient; air standard of 1.19 a lack of factors cast not ba used, to st not ___ risk WIBftf* proposed flwfri ent air rule does where Cone for vinyl 8.4xl0'r of lorids of 1.19 jig w is arbitrary ial to standard a unit risk factor of there is a lack such values. WMt^T.nnTQM The VI opposes the proposed ambient air standard for vinyl: chloride > because there is '.s': fe.Pt substantial evidence to- support this^staiidard* For the reoepns discussed above, DEQ must provide full notice and comment rulemaking procedures concerning,., the de^ilopieiifc, and underlying. scientific ^ bases' for the unit risk factor for vinyl chlorite. VI plane to submit an based on e the vi does not. risk-. factor, it i s the in therecord which is besei on an The Document on a unit risk factor based on not a valid value for - regulation Finally, chloride end the unclear. i u-h 'i: 'I: Amendments, wa any air toxics the federal system is F on vinyl e are tor* . Clean Air:; Act louisianadefer ..finalising ons until the regulatory framework of h place. sincerely Fetor I*, de la Crus General Counsel Vinyl Institute VAB.0001125538 A AIR DISPERSION MODELING OF ABERDEEN VCM EMISSIONS Our plant has recently had some trouble in obtaining air permits allowing our current operation. This report details some aspects of the theoretical concentrations of VCM in the vicinity of our plant, as determined by the same mathematical model that would be used by a regulatory agency to determine compliance. VCM SOURCES ON THE PLANT SITE A great deal of engineering work has been done and will be done to reduce the VCM concentration in the slurry. Reducing VCM in the slurry reduces the emissions of all the equipment downstream from the reactors, i.e. the stacks, but does not affect the emissions . from the fugitive sources, i.e. the sphere, ponds, and reactors.f*f*o VCM concentrations for different slurry concentrations are shown in figures 1-3. To learn the nature of the contributions that different sources make to the VCM concentrations at various locations the sources were divided into logical groups, and the VCM concentrations contributed by each of these were determined. These group contributions are shown in figures 4-7. Also of interest is the location of residences in the vicinity of our plant. These are shown, with VCM concentrations of the three different slurries overlaid, in figures 8-10. The highest concentrations at the fenceline and at the residence with the highest concentration are of importance and are tabulated: source fugitive soui 25 ppm plant 100 ppm plant 200 plant WMMP emissions (lb/yr) 3000 max. fenceline concentration (Mg/m3) 5.81 max. residence concentration (ug/m3) 0.4 12600 15600 2.10 7.90 0.7 1.1 50400 53400 7.33 13.13 2.6 3 100800 103800 14.30 20.11 4.6 5 VAB.0001125539 +* >i ..i A 4 Notice that the fugitive sources contribute little to the VCM concentration at the closest residence, but contribute a great deal to the fenceline concentration, especially at low slurry concentrations. The fenceline contributions from the fugitive sources come largely from the sphere; it does not contribute an overwhelming weight of VCM per year but because its emissions must only travel about fifty feet, they are still highly concentrated when they get to the fence. Our plant is caught in an unfortunate set of circumstances; the wind often blows to the northwest, the shortest distance for most of the stacks to the fenceline is west, the sphere lies northwest from the stacks, and to the west is one of the few places where our fenceline is our property line. BEHAVIOR OF THE STACKS It has been suggested that one of the possible ways to lower our me concentrations was to alter characteristics of the i. e. their height, diameter, or exit velocity. A model was run where all of the exit velocities of the major (dump screeners and blend tanks) was (arbitrarily) doubled, This model showed that the maximum ine concentration dropped to 11.2 Mg/m3 for a 100 ppm slurry, or a drop of only 15%. Furthermore, VCM is heavier than air, at longer distances it will eventually and as such, long-range concentrations will not change much It was assumed that lowering the stack diameter or the stack height affected the concentrations in a similar manner. Each of the stacks on the plant site of Currently, the blend tanks and the dump contribute the largest percentage of the emisssiioonnss.. The model was run to determine what of the maximum ine concentration each ofi tzhnee major stacks responsible The results are shown in figure 11 This figure points out that some stacks contribute VCM to the me concentration m disproportionally large or small amounts. The D300 dump screener and the 503 blend tank contribute higher amounts to the fenceline concentration than they should, while the D745 screener contributes considerably less than it should, based on their emission rates. While some of this ion is due to location (D745 is 250 feet further from the maximum fenceline concentration point than D300) some is also due to stack design. D300 has the shortest stack and the lowest flow of the Note that only minimal work has been done in this area so far, as there is an almost infinite variety of different combinations of different stack heights, exit velocities and stack diameters to try. Considering altering the stacks could be very expensive, this VAB.0001125540 t A does not represent the most efficient way to lower the fence line concentrations, and is certainly not capable of lowering them by an order of magnitude. However, it might be possible to pursue this further if we are close to a concentration that is desirable. It is also possible that reproportioning the air flow to each blend tanks could lower the fenceline VCM concentrations somewhat. UNIT RISK FACTORS AND EXCESS CANCER BURDENS Generally the excess cancer risk to humans for exposure to given concentrations of a certain carcinogen is evaluated by using toxicological studies on laboratory animals. Unfortunately, there is controversy in the interpretation of these studies, and as a result there is tremendous disparity in the unit risk factors for different states. The unit risk factors that may be applicable to us now or in the future are listed below, along with the minimum concentration that gives an unacceptable cancer risk: State Mississippi Current value EPA New value EPA Old Value California Proposed value Unit Risk Factor (Mg/m3)-1 42 10-e 16.1 10-6 2.72 10-e 78.1 10-6 maximum exposure (cancer risk of 10-*) (Mg/m3) 2.38 6.21 36.8 1.28 Mississippi's current unit risk factor was given to us by the state and touched off this whole air permit dilemma. Dr. Peter Voytek, an environmental consultant currently employed by our company, insists that Mississippi based their number on a new toxicological study used by the EPA, but that Mississippi's unit risk factor was calculated incorrectly from that study. Voytek thinks that the unit risk factor correctly deduced from this study should be equal to the EPA new value. Furthermore, Voytek thinks that the study that the EPA bases its new unit risk factor on is severely flawed, and has not undergone sufficient scientific review as yet. He feels that the EPA should use its old unit risk value until its new one has been reviewed and VAB.0001125541 4 approved (if in fact it is approved). Although it may be straightforward to convince the state that a mistake in the calculation was made, convincing the EPA that scientific data that it uses are invalid may be another thing entirely. The unit risk factor for the state of California is currently being proposed. It is included here to point out how low our fenceline concentrations would have to be if this value is later accepted throughout the country. CONCLUSIONS AND RECOMMENDATIONS From this report it can be concluded that exist to get our air permit. Their effecti possible ways in meeting this 1. Move our "fenceline". This fenceline might be our actual fenceline, our property line, the limit of the property on which we can purchase easements, or the limit of actual residences, and is whatever boundary the state feels will not be populated. In any event, the further you get away from our plant, the lower the concentration of VCM becomes. Buying property off our west fenceline is especially attractive because of the large drop in concentration with increasing distance in that direction. 2. Get the State of Mississippi to agree to lower their unit risk factor. This is discussed in more detail above. I personally cannot judge the effectiveness of haggling with government bureaus. Any effort spent in this area is a gamble; if we can convince the state to lower its unit risks, then we could possibly get our permit with no further effort. If we do not, then the effort is wasted. There is also nothing that prevents the EPA from adopting a new unit risk factor at any time, either. Apply for an air permit with lower slurry VCM levels than the 250 ppm originally proposed. This method is the only real way to lower distant concentrations (concentrations at great distances are linearly related to the slurry concentration). Of course, we must be capable of meeting our permit levels in our standard operations.3 3. Lower the emissions of our fugitive sources, especially the sphere. This would present legal difficulties as much as anything since our current reported values are theoretical and are based on the previous determination of the emission rate of an average valve or flange in our plant. I do not know if changing the emission rate of fugitive sources as far as the state is concerned is reasonable. This method would be effective in lowering our fenceline concentrations fog oS3l?25542 current location of the fenceline, but would not be good for much else. 4. Change characteristics of the stacks. This could possibly include increasing the height, decreasing the diameter, or increasing or reproportioning the air flow rate in the stacks. Further analysis could be done to identify the most costeffective ways to lower the fenceline concentrations. This method could only decrease the fenceline concentrations a little bit, and might be employed to "fine tune" the fence line concentration. This method has a negligible effect on the long range concentration. VAB.0001125543 V -- II wJH f /\ C I ^ A i V I V W W * v : t VUV 4 V < I 1 L * I 3 rw * "'if iJin INHALATION RISK ASSESSMENT An Inhalation riok aaaaaaaant waa oonduotod for off-aita exposures to vinyl chlorite aaiaaiona froa tha Viata Polyaara plant in Aberdeen, Miaaiaaippi. Tha potantial inhalation riaka vara aaloulatad by oosfelnlng a unit riak factor for vinyl chlorite vith diaparaion aodeling raaolta of aaiaaiona fron tha Viata Polyaara plant. Tha diaparaion aodaling vaa conductad by paraonnal at tba viata Polyaara plant and raaolta vara providad to dcaant Intamational, Inc. for oaa in tha riak aaaaaaaant. Anbient air conoaatrationa aaaooiatad with vinyl ohlorida aaiaaiona wara datarainad using tha Xndaatrlal .Source coaplax Short-Tara (ISCST) air dispersion nodal. lactT ia an SPA raooaaandad nodal for oaa in induatrial settings auoh aa tha viata Polyaara plant. Tha XSCST nodal waa run in tha regulatory dafault note whioh automatically aalaota nodal optiona raeonaandad for uaa by tha SPA. Mataerologioal data fron tha Montgomery Alabana National waathar darvlaa atation, for tha yaara 1966 to 1970 wara uaad in tha XNCST nodal. A aaparata nodal run waa oonduotad for aaeh of tne fiva yaara of aataorological data uaing a polar grid with 36 radiala (10 dagraaa of are par radial) and raoaptora plaoad at 100, 150, 200, 300, 400, 500, 750 and 1000 natara frea tha plant along aaah radial. Emissions froa tha plant wara oharaotariiad in tha IBCST nodal by 34 aaparata anisaion aouroaa. Thaaa aouroaa included both controlled ataok aaiaaiona aodalad aa point aouroaa, and fugitive aaiaaiona aodalad aa both voluae and area aouroaa. Analyeia of tha X8CST nodal raaolta for aaoh of tha fiva yaara of aataorologioal data indicated that tha 1970 data raaultad in tha highaat annual avaraga concentration for off-eite raoaptora. A aecond xacar nodal run waa than oonduotad uaing tha aaae aaiaaiona inputa end nodal optiona with a eartaaian grid of receptor pointa at 200, 400, 600, 800, 1000, 1250, 1500, 1750, 2000, 3000, 3500, 4000, and 5000 natara fron tha plant in all diraotiona. Thia raaultad in nodal prediotione of annual avaraga eonoantratiana at 676 raoaptora around tha plant. Tba reaulta froa thia nodal run wara uaad by claneat international, Inc. in tha inhalation riak aaaaaanant. H The first stsp in the inhalation risk assessment vaa to identify tha receptor locations to ba evaluated Wo receptor grids vara construotad for evaluation* in tha first raoaptor grid modal raoaptora located within the fanoe line boundaries of the plant were eliminated from the evaluation. In addition, modal concentrations for receptors beyond 3500 maters from tha plant were also eliminated from the evaluation because tha concentrations would result in negligible inhalation risks relative to tha oloser raoaptor locations evaluated and in the majority of oases they ware beyond the populated areas around the plant. The second grid used in the inhalation riak assessment used the same receptor locations as the first vith the exception VAB.0001125544 I. AC i ^A C % v M * W I i C i i i 4 v I OTui % *L * vxOin i *w * that raoaptora 1ocatad within tha plant boundaries but outaida of tha fane# lina vara axoludad. For both of tha grida avaluatad in tha inhalation risk assessment tha maxima and avaraga modal predicted annual avaraga concantrationa vara used* Tha avaraga oonoantration uaad in tha evaluation van tha arithmatlc avaraga of all modal pradiotad annual avaraga oonoantrationa for tha receptors within aaoh grid avaluatad. Nota that the us* of an arithmatlc avaraga aaaumaa an agual waightlng of all modal pradictad oonoantrationa . However, tha spacing of tha receptor grid increased with dlatanoa from tha plant, vhlla modal pradiotad oonoantrationa daoraaaad with dlatanoa from tha plant. Thus tha avaraga oonoantration uaad in thia assessment ia oanaarvativa sinoa a regular apaoing of tha grid out to 3800 motors from tha sito would havo included many more oonoantrationa with lower valuaa than thoee pradictad for raoaptora looatad within 1000 metsrs of tha plant, resulting in a lower arithmetic avaraga oonoantration. The ISCSI aodal results uMd in th inhalation riak aaaaaaaant vara baaed on a 200 parts par million (ppa) vinyl chloride content in tha lurry. Ha riak aaaaaaaant hewawsr was oonduoted for a 190 ppa and 400 ppa vinyl ehiofida slurry concentration. According to VXMA Polyaar paraonnal the aodal results oould ha scaled for tha changes in vinyl chloride slurry content, vista Polyaar paraonnal indioatad that ealasioas froa only a portion of tha 34 auuroaa avaluatad in tha zscra aodal would be atfacted by ahangas in tike slurry content. They had oonfigurad the X8CST aodal to oalouiata raeaptor concantrationa aaparataly for two sourca group*. One aouroo group rspraaantad saissions froa tha 19 souxooa (aouroo numbers 1-19) that ware affected by slurry content. Tha second aouroo group raproaontad tha 19 raaaining souroaa (aouroo nuabars 20-34) whoso aaiaaions wars unaffected by slurry content. She oonoantration at a raoaptor for all aodalad vinyl chloride emissions froa tha plant is than tha sua of the oonoantration at tha raeaptor for oaoh aouroo group, vibta Polyaar parsonnal providad tha following algorithm to oonv.rt tha 200 ppm Blurry results to tha desired Blurry content: x. <x.y> -x (* y> *, <*,y> where: l. " oonoantration at a point due to all souroes aoabined, (ug/m3), Xi ".oonoantration at a point due to eourea numbers 20 to 34, (ug/m3), y2 m oonoantration at a point dua to oouroa numtoara 1 to 19, <ug/m*f, p i DSC * tha daairad concentration of vinyl chloride in tha VAB.0001125545 H'WMI f mm IT 4 KmuMrcamNL mmm - a tear cooany mMMIIMtMMHMtttl * fOTfMMMtt NRVET * miMtuiiMMiiiimi m coocal commv nmumt MOTV :* VCM^VVV * QMlTV ItC PLANTV MWV 11/19/49 - 12/2/0 csvmit 9F roSITIVC EMSUMS n Ml IMIlUil DOM FKIW A itiiMiimmHtttmtt * vcm omtnm ttaaaaaaatatatai mL \. * +-H nm in mil inthno/iem) - t; - ?.!!: i f- , *' > xlj ri` r i 'Mm: ft., *i1 E;F.A. C9999UI190 muraitar neno no non* nth WbIvm fat a HL Ms LL -NL /* alitf at as HI IlMf HI Total '""09 9190.9 717 10449.91 90 27 29791.72 99 12 92729.19 99 094 11901.39 9 "9 383754 7171.42 14199.19 0 9 21719.23 9 194.21 9 67958 440.17 9.99 .44 9.99 9.99 9.99 14532 V i. i 4h* *- / 419 9.99 r 9.99 21293 09* M9HOMT4 HI Ot YULI fTITltlKtaY HV7DCM7 QOSflM RAIEFtO Till 9T EPA 09: O OTA M OT 9AIA. AVULAKE II OO fTATItTICAL C9HM9I90 II C79 I jwnr O. {n^*0 9.99 9.99 900 3007.71 a L *'' all nano aramis olt znr fact that leak 9.719 I r A1 -T XH '9 ? .... "j. VAB.0001125546