Document BRX0G8vY900M3oMJ4bw9J4Jow

TOXICOLOGICAL DATA AID INDUSTRIAL EXPERIENCE WITH VINYL CHLORIDE Testimony of )r, V, K. Rowe research Scientist )ow Chemical USA MIDLAND/ Michigan Public Hearing on Vinyl Chloride Occupational Safety and Health _ Administration Department of Labor WASHINGTON/ D. C, February 15/ 1974 APOOOOO!f 3 TABLE OF COIfTENTS INTRODUCTION I. ' Scope of the Vinyl Chloride Industry II. Toxicology of Vinyl Chloride III. Health Parameters Studied in Vinyl Chloride workers IV. V. VI. Industrial Hygiene Safety in the Vinyl Chloride Industry Analytical Methodology VII. Recommendations for Government-Industry Action IAppendix Published References to theBiological Effects of Vinyl Chloirde (Including chemical abstracts 1562 - January 14, 1974 and Biological Abstracts 1962- Appendix II. c Industrial Hygiene Surveys Involving Vinyl Chloride j (Each appendix to the testimony is a complete vollwe IN A HARD-BACK BINDER. EACH IS SUBMITTED IN TRIPLICATE). APOOOOOif4 INTRODUCTION m V, U.S.A, II K, Rowe of Dew Chemical Currently am a rese/ach SC^TIST CONCERNED WITH THE OYER-ALL BROAD ASPECTS OF Dow'S HEALTH and 5.viro;,'-ntal Research. Prior to being naked to this post in late W5, I was Director of our Toxicology .Moratory and Industrial Hygiene research. I SHALL SUMMARIZE FOR THE RECORD THE.FOLLOW]NG: (1) SCOPE OF THE VINYL CHLORIDE INDUSTRY; (2) THE BASIC TOXICOLOGICAL INFORMATION; (3) THE HEALTH PARAMETERS STUDIED IN VINYL CHLORIDE WORKERS; W) OUR INDUSTRIAL HYGIENE EXPERIENCE IN ALL OF OUR PLANTS; (5) ANALYTICAL AND MONITORING PROCEDURES; (6) ITEMS FOUND EFFECTIVE IN MAINTAINING SAFE OPERATING CONDITIONS; AND FINALLY (7) SOME SUGGESTIONS FOR THE FUTURE. .1 BELIEVE IT WILL BE APPARENT THAT THE INDUSTRY LEARNING CURVE FOR VINYL CHLORIDE IS FAR ADVANCED. i APbbbbbits 2- - I. SCOPE OF TIE VINYL CHLDRIDE INDUSTRY Dow U.S.A.Chemical began producing vinyl chloride monofer on a very MODEST SCALE IN MIDLAND; MICHIGAN, IN 1339 AND PRODUCTION REMAINED RELATIVELY LOW THROUGHOUT- THE WAR PERIOD. In 19^6, PRODUCTION OF VINYL CHLORIDE BEGAN IN OUR TEXAS DIVISION AT FREEPORT, TEXAS. InCapacity was expanded at this location through 1956. 1358 our SECOND MONOMER PLANT WAS BROUGHT ON STREAM IN PlAQUEMINE, Law AND INA THIRD WAS ADDED IN 1969 AT OUR OYSTER CREEK DIVISION. 1952 -DOW WAS ONE OF SEVEN U.S. PRODUCERS OF THE MONOMER AS REPORTED IN THE U.S.first Tariff Commission report on vinyl chloride. Today there ARE TEN PRODUCERS OF VINYL CHLORIDE MONOMER; Dow BEING ONE OF THE ILARGE MERCHANT SUPPLIERS. n ADDITION TO PRODUCING MONOMER, DcW OPERATES A S[-V\LL POLYMERIZATION PLANT. U.S,The QUANTITY OF VINYL CHLORIDE PRODUCED IN THE HAS GROWN QUITE rapidly. Production increased from approximately 321 million pounds IN 1952 to 1 billion pounds in I960; 2 billion pounds in 1955; 4 BILLION IN 1970, TO AN ESTIMATED 5.3 BILLION IN 1973. THIS MONOMER GROWTH RATE ILLUSTRATES THE HIGH DEMAND FOR THE PLASTICS PRODUCED FROM VINYL CHLORIDE (SEE FIGURE D. VlNYL CHLORIDE IS THE SECOND LARGEST VOLUME MONOMER PRODUCED IN THE UNITED STATES. THERE ARE TWO COMMERCIAL PROCESSES FOR PRODUCTION OF THE MONOMER, ONE ROUTE INVOLVES THE ADDITION OF HYDROGEN CHLORIDE TO ACETYLENE. HCT+ (MH------- ->CH2<HC1 APOOOOOIf 6 u.s. -3- !ERS OF VI-NYL CHLORIDE H fd 0 .Year Total U.S. Production Million Pounds *' a *rt jG O H a 0 0 <Eb J5 0 u *0 cti Xi 0 Oc0C oj a d) 'O dJ H yE u pi rl p f--( < 0) c & 00 0a 0 0 0> c c a> H E 0 x: 0 0 C 0 S H (0 O H .s 0 Xi 0 H 0 O' CU ce a u 0 0 H jj w TJ G 0 E <d H a 0 0 O tH U .o u EH aj 0 rH <d cU 0O rt C GO Da 0 -p c Cj 0 c 0 s 0 0 .< 0) T? XI c cd X) 4 3 --1 CVJ C5 uO <u > , & B3 XO3 O CO . OO 1973** 5,333 1972s* 5,109 X XX XXX X XX X X XX XXX X XX X 1971 4,336 X XX XXX XXX X 1970 4,0*10 X XX XXX XX XX 1969 3,736 X XX XXX X X XXX 1968 | 1967 2,969 2,424 X XX XXX X X X XX XX XX X X X'XX XXX X X 'X X 1966 1 1965 j 1964 2,500 2,000 1,615 X XX X. X X X XX XX X X X X X XXX XXX XXX XX X X XX X X XX X X 1963 1,435 X XX X X XXX X X X X j 1962 1,313 X XX X X XX X XX X X 1961 1,044 X XX X X X XXX XXX I960 1,037 X XX X X X XXX XXX ] 1959 978 X X X 1958 691 X X X 1957 627 X X x XXX XX X X XX X XX X XX 1956 597 X X X XX X XX `1955 L95i 529 393 XX XX XX XX X XX X XX 1953 402 XX ` XX X XX- I -L952 321 XX XX X XX Source: U.S. Tariff Commi. sion Annual Reports chloride began in 1952) (Repo: ;ing of quantity of vinyl U.S. Tariff Commission 1973 quantity estimates - Mo nthly Reports (subject from 11-month data. to revision) AP00000117 However, the principal process, used by Dow and host other producers U.S.,IN THE INVOLVES THE THERMAL DEHYDROHALOGENAT ION OF ETHYLENE DlCHLORfDE. CH2CICH2Q----------- *> Q^CHCl + HC1 Vinyl chloride is one of the purest organic- compounds produced commercially. A TYPICAL ANALYSIS OF VINYL CHLORIDE PRODUCED BY DOW SHOWS LESS THAN 20 PPM OF TOTAL ORGANIC IMPURITIES. THESE TRACE ORGANIC IMPURITIES ARE ACETYLENE., 1,3-BUTADIENE, METHYL CHLORIDE, AND VINYL ACETYLENE. .Nearly all vinyl chloride monomer shipped by Dow is uninhibited; however, A SMALL MOUNT IS INHIBITED WITH 25"75 PPM PHENOL. THE PHENOL IS SUB SEQUENTLY REMOVED BY USE OF A CAUSTIC WASH, I WISH TO EMPHASIZE THE DIVERSITY OF PLANT AND PROCESS OPERATIONS IN PRODUCING AND USING VINYL CHLORIDE, COMMERCIAL PLANTS FOR PRODUCING VINYL CHLORIDE RANGE IN CAPACITY FROM MODEST SIZE UP TO SEVERAL HUNDRED MILLION POUNDS, SOME ARE NEW PLANTS, SOME ARE 15 TO 20 YEARS OLD, Three distinctly different polymerization processes have been commercialized TO PROVIDE THE WIDE VARIETY OF ESSENTIAL PLASTIC MATERIALS PRODUCED FROM APO6OO6TI8 5- - VINYL CHLORIC (SUSPENSION, EMULSION, AND BULK PROCESSES). POLYMERIZATION RECIPES AND SCHEDULES ARE OF NECESSITY QUITE VARIED. POLYMERIZATION PLANTS ARE BOTH OPEN-AIR AND ENCLOSED, I WILL CITE MANY OF OUR PLANT PRACTICES, BUT STRONGLY RECOMMENDED TOT OSHA RECOGNIZE THE DIVERSITY OF MONOMER MANUFACTURING AND POLYMERIZATION OPERATIONS IN CONSIDERING THE ESTABLISHMENT OF A WORKPLACE STANDARD OR STANDARDS, OTHER PRODUCERS AND PROCESSORS WILL HAVE DIFFERENT TYPES OF JOBS, DIFFERENT EQUIPMENT, AND DIFFERENT ENGINEERING, MONITORING, AND PROCEDURAL APPROACHES, DCW STRONGLY BELIEVES TOT A STANDARD SHOULD . EMPHASIZE IN OBJECTIVE TERMS WHAT IS TO BE ACCOMPLISHED SO TOT A NUMBER OF ENGINEERING AND PROCEDURAL APPROACHES MAY, BE EMPLOYED WBER THE STANDARD, DEPENDING ON THE-PARTICULAR PLANT SITUATION. APOOOOOI19 6- - II. TOXICOLOGY OF VliJYL CHLORIDE Earliest studies on vinyl chloride were limited to acute exposures,, as TYPICAL OF TOXICITY STUDIES OF THE DAY, THESE OBSERVATIONS LED TO ITS CONSIDERATION AS A SURGICAL ANESTHETIC, GENERALLY,THESE STUDIES SHOWED VINYL CHLORIDE TO BE LOW IN ACUTE TOXICITY, TO BE ANESTHETIC IN ACTION, AND TO HAVE LITTLE CAPACITY TO CAUSE LIVER INJURY FROM EXPOSURES OF A FEW HOURS. MASTROmTEO EX L. (I960) AND LESTER EX AL, 0963) REPORTED ON ACUTE EXPOSURES OF ANIMALS AND HUMANS. They reported very little effect until exposure concentrations approached ]D,000 5 NoPPM WHEN HUMANS REPORTED DIZZINESS AFTER MINUTES EXPOSURE, DEATHS OCCURRED IN RATS EXPOSED FROM 1/2 TO 2 HOURS TO 390,000 PPM, Exposures to 150,000 to 200,000 ppm for 1/2 to 2 hours caused anesthetic DEATHS.AS DID HIGHER CONCENTRATIONS FOR SHORTER PERIODS OF TIME, J AP00000I20 -7- i ACUTE INHALATim CF TOXICITY ' OF VINYL CHLORIDE 1 * ' i i " "- I 1 i i 1 1 i i Rats, mice, and GUINEA PIGS CONCENTRATION (PPM) moco = ODD 200,000 morn Guinea pigs Rats ttwms mooo 100,000 150,000 None 4,000 ... 8,000 12,000 16,000 20,000 Death or Other Effect No 0.5deaths in hr 1/15 (1/5 mice) 11/15 (5/5 RATS AND MICE 1/5 GUINEA PIGS) 2/5 (1 IMMEDIATELY, 1 IN 24 HR3) 2NO DEATHS IN HRS O) 2 21 OF DIED IN HRS (n\ 1/6 SLIGHT DIZZINESS IN 5 MIN V 0/6 1/6 SLIGHTLY UNSTEADY 2/6 (1 SLIGHTLY UNSTEADY, 1 REELING) Intoxication of varying degree Intoxication of varying degree. MORE SEVERE 0.) ^Hastowho el ALw AIHA J,_2L 394 (I960) . (2) Lester, Greenberg and Adams, AIHA J,_2b 265 (1963) AP6boo6i2i 8- - SOME LUNG CONGESTION AND EDEMA WERE PRESENT AFTER 42 MINUTES EXPOSURE TO 150,000 PPM, BUT LIVER AND KIDNEY INJURY WERE NOT APPARENT. Since 1952, numerous non U'.S. articles on vinyl chloride have appeared, PARTICULARLY IN THE RUSSIAN LITERATURE, SEVERAL OF THESE STUDIES INVOLVED ACUTE EXPOSURES AND THE OBSERVED EFFECTS WERE GENERALLY SUBTLE REVERSIBLE CHANGES. The chronic toxicity of vinyl chloride has been studied by several INVESTIGATORS, TORKELSON, OYEN, AND RoWE (1961) REPORTED THE FOLLOWING RESULTS, Results of Repeated Seven-Hour Daily Exposures to Vinyl. Chloride^ Exposure , Em Does-Months_____ R .Guinea,,p_i_G__ ats EflBBUS 500 4.5 NOT EXPOSED NOT EXPOSED SLIGHT LIVER & NOT EXPOSED KIDNEY HIST0PATH0L03Y (central lobular granular DEGENERATION AND INTERSTITIAL & TUBULAR CHANGES) 200 6 i NO EFFECT NO EFFECT SLIGHT LIVER WEIGHT INCREASE SLIGHT LIVER HISTOPATHCLOGY (CENTRAL LLC'JLAR DEGENERATION & NECROSIS WITH VACUALATIC.N AND SOME PERIPORTAL CELLULAR INFIL TRATION) 100 6 NO EFFECT NO EFFECT SLIGHT LIVER WEIGHT INCREASE NO EFFECT 50 6 NO EFFECT . NO EFFECT NO EFFECT NO EFFECT AP00000122 -9- They concluded tot WORKERS EXPOSURE should be limited to less than 100 PPM WITH A TIME-WEIGHTED AVERAGE MOT TO EXCEED 50 PPM. Lester, Greenberg, and Adams took exception to conclusions of Torkelson, ET AL AND RECOMMENDED 500 PPM AS A TIME-WEIGHTED AVERAGE EXPOSURE. BESULT OF REPEATED SBEfcHOUk^^ bais_to vinyl chlorite Exposure Conditions B50.000 ppm - days 20.000 ppm - 90 days ` -Result Incoordination. Normal hematology. Increase LIVER WEIGHT. NORMAL GROSS PATHOLOGY. SLIGHT LIVER HISTOPATHOLOGY, Normal hematology. Increased liver weight. Normal gross pathology, Slight liver HISTOPATHOLOGY, WHICH WAS CONSIDERED TO BE WITHIN NORMAL LIMITS. AP00000123 10- - BECAUSE OF THESE CONFLICTING REPORTS, THE TLV COMMITTEE OF THE ACGIH in 1963 chose to change their TLV from 530 ppm as a maximum time-weighted TO PPMAVERAGE FOR INDUSTRIAL EXPOSURE 500 AS A CEILING VALUE. Conference of Governmental Industrial Hygiene^ 1963), (AMERICAN # Because of the report of acroosteolysis in humans. Professor P, L, Viola of the Regina Eleva Institute for Cancer Research in Rome, Italy, attempted TO PRODUCE THE DISEASE IN ANIMALS. He EXPOSED RATS A HOURS PER DAY, 5 DAYS .PER WEEK TO 30,000 PPM (3%) VINYL CHLORIDE VAPOR. (VlOLA, MARCH 1970), In HIS FIRST REPORT ON THE RESULTS OF 12 MONTHS EXPOSURE, HE DESCRIBED METAPLASTIC CHANGES IN THE BONES WHICH HE CONSIDERED SIMILAR TO THE HUFAN DISEASE ACROOSTEOLYSIS. He MADE NO MENTION OF FAYING Q3SERVED CANCER IN THESE ANIMALS UNTIL THE TENTH INTERNATIONAL CANCER CONGRESS IN MAY 1970, In THE ABSTRACTS OF THIS MEETING, (VlOLA, 1970), AND SUBSEQUENTLY IN May 1971, Viola, Bigotti, and Caputo (1971) reported tutors of the skin, LUNGS, AND BONES OCCURRING FIRST AFTER 10 MONTHS EXPOSURE. THE AUTHORS SUMMARIZED THIS WORK AS FOLLOWS! Apobboom -n- "Rats CAr/IRE' VJistar strain) exposed for 12 months to vapors of vinyl CHLORIDE DEVELOPED TUMORS OF THE SKIN, LUNGS, AND BONES. THE CUTANEOUS TUMORS, which always appeared in the area in which submaxillary and PAROTID GLANDS ARE LOCATED, HAVE BEEN HISTOLOGICALLY RECOGNIZED AS EPIDERltilD CARCINOMAS, PAPILLOMAS, AND MUCOEPIDERMOID CARCINOMAS. THE MORPHOLOGICAL CHARACTERISTICS OF LUNG TUMORS, VIHICH OCCURRED IN A LOWER PERCENTAGE, WERE MAINLY OF THE ADENOCARCINOMA TYPE, WITH THE EXCEPTION OF A SINGLE EPIDERMOID TUMOR ORIGINATING FROM THE EPITHELIAL COVERING INCELLS. A MINOR NUMBER OF RATS, A LARGE PROLIFERATION OF CARTILAGINOUS TISSUE DIAGNOSED AS OSTEOCHONDROMA DEVELOPED IN THE METACARPAL AND NTATARSAL REGIONS OF THE FOUR LIMBS,W This report by Viola jei.aiJ is apparently the earliest and only publication ALIN IHICH CARCINOGENIC ACTIVITY HAS BEEN ASCRIBED TO VINYL CHLORIDE, THOUGH there are possible deficiencies in Viola's study, such as the QUALITY OF THE VINYL CHLORIDE SAMPLE USED IN THE STUDY, THE PRESENCE OF FOOD AND BEDDING IN THE EXPOSURE CHAMBER, AT THE EXCESSIVE EXPOSURE CONCENTRATION USED, THE REPORT NEVERTHELESS GAVE RISE TO SERIOUS CONCERN AND RESULTED IN THE INITIATION OF ADDITIONAL ANIMAL STUDIES AND EPIDEMIOLOGICAL (MCASTUDIES WHICH ARE CURRENTLY UNDERWAY PRESS RELEASE). AP00000I25 I J I I 1 [ i V \ \t , i, 1 12 - Summarizing, it should be emphasized: A. ' B, C, Acute effects from short term exposure occur : ONLY AT HIQ-1 ENVIRONMENTAL CONCENTRATIONS, Chronic or long-term effects occur at moderate ; CONCENTRATIONS. The MOST SENSITIVE TOXICOLOGICAL RESPONSE OBSERVED TO DATE IS THE EFFECT ON THE ' LIVER. The CENTRAL NERVOUS SYSTEM EFFECT IN HUMAN BEINGS IS RELATED TO THE CONCENTRATION OF INHALED AIR, WE ARE SUBMITTING TRIPLICATE COPIES OF THE TOXICOLOGICAL LITERATURE ON VINYL CHLORIDE FOR OSKA REFERENCE. THESE ARE APPENDIX I OF THIS TESTIMONY, / AP00000126 III. HEALTH PARAMETERS STUDIED III VDRKERS DdW IS COOPERATING WITH THE MANUFACTURING CHEMISTS ASSOCIATION WHICH HAS RETAINED TABERSHAW-COOPER TO EO AN INDUSTRY-WIDE STUDY OF THE HEALTH OF WORKERS EXPOSED TO VINYL CHLORIDE. CURRENTYL, WE HAVE APPROX IMATELY 320 EMPLOYEES IN VINYL CHLORIDE OPERATIONS. WE HAVE SUBMITTED TO TABERSHAW-COOPER EMPLOYEE RECORDS COVERING 916 PERSONNEL WHO HAVE BEEN INVOLVED IN VINYL CHLORIDE OPERATIONS OVER THE YEARS. THIS STUDY IS INCOMPLETE AND WH_L BE REPORTED AT AN APPROPRIATE DATE. HOWEVER, WE CAN MAKE THE FOLLOWING PRELIMINARY COMMENTS ON THE HEALTH PARAMETERS OF DOW VINYL CHLORIDE WORKERS. Preliminary data from Dow manufacturing units reveal no deaths due to CANCER OF THE LIVER. Preliminary data likewise reveal no deaths due to cirrhosis of the LIVER. We have no cases OF acroosteolysis. ' At THE PRESENT time, we are unaware of ANY living employee who HAS BEEN EXPOSED TO VINYL CHLORIDE SUFFERING FROM CANCER OF THE LIVER. Likewise, we wiow of no case of cirrhoiss of the liver in employees EXPOSE) TO VINYL CHLORIDE. HOWEVER, THIS INFORMATION IS INCOMPLETE AND IS BEING SUBJECTED TO A CRITICAL SEARCH. AP66660I27 -l'l- PRELIMINARY STUDIES IN TWO MAJOR MANUFACTURING LOCATIONS, WITH THE LONGEST HISTORY OF VINYL CHLORIDE PRODUCTION, REVEAL NO INCREASE IN ABNORMAL LIVER FUNCTION TESTS ABOVE THAT EXPECTED IN A SIMILAR UNEXPOSED POPULATION- ft C. G. KRAMER, M.D. AND J. E. MUTCHLER PUBLISHED IN THE AMERICAN INDUSTRIAL HYGIENE ASSOCIATION JOURNAL IN 1972, A STUDY OF VINYL CHLORIDE WORKERS IN ONE LOCATION. FINDINGS SUGGEST THAT REPEATED EXPOSURE TO VINYL CHLORIDE AT TWA LEVELS OF 300 PPM OR ABOVE FOR A WORKING LIFETIME TOGETHER WITH A VERY LOW LEVEL OF VINYLIDENE CHLORIDE MY RESULT IN SLIGHT CHANGES IN CERTAIN PHYSIOLOGICAL AND CLINICAL LABORATORY PARAMETERS. THE POSSIBILITY OF SOME IMPAIRMENT IN LIVER FUNCTION MUST BE CONSIDERED, EVEN THOUGH NO OVERT CLINICAL DISEASE WAS EVIDENT IN ANY OF THE INDIVIDUALS STUDIED. THIS STUDY SHOWED A DEFINITE DOSE-RESPONSE CORRELATION BETWEEN THE INTENSITY OF EXPOSURE AND THE DEVIATION FROM NORMAL VALUES. WE WILL CONTINUE TO COOPERATE WITH THE MANUFACTURING CHEMISTS ASSOCIATION IN THE TABBRSHAW-COOPER STUDIES. ADDITIONAL INDEPTH STUDIES WILL BE CONTINUED WITHIN THE VARIOUS MANUFACTURING UNITS OF THE COMPANY AND WILL BE REPORTED UPON WHEN COMPLETE. AP00000128 -15- IV. INDUSTRIAL HYGIENE'MEASUREMENTS OF VINYL CHLORIDE IN WORKPLACE . DOW HAS MONITORED THE WORKPLACE ENVIRONMENT BY A VARIETY OF TECHNIQUES, INCLUDING: . (A) CONTINUOUS MONITORING OF REPRESENTATIVE OR SELECTED WORKPLACE AREAS BY A COMBUSTION - CONDUCTIVITY ANALYZER. <B) "GRAB" SAMPLES OF WORKPLACE AIR COLLECTED IN IMPERVIOUS PLASTIC BAGS OR ACTIVATED CARBON "SLUGS" (ABSORPTION). ANALYSIS OF SUCH SAMPLES IS NOW BY GAS CHROMATOGRAPHY, BUT YEARS AGO ANALYSIS WAS BY DETERMINATION OF TOTAL CHLORIDE OR BY INFRARED SPECTROSCOPY. (C) PERSONNEL MONITORS BASED ON ABSORPTION ON ACTIVATED CARBON SLUGS, FOLLOWED BY GAS CHROMATOGRAPHIC ANALYSIS. MONOMER PLANT #1 STARTED OPERATION IN 19^6. HISTORICALLY, SPOT SAMPLING WAS CONDUCTED. LOADING OF TANK CARS, COLLECTION OF SAMPLES FOR PRODUCT ASSAY AND DISTILLATION OPERATIONS WERE THE ONLY TASKS WHICH NEEDED ATTENTION IN THE EARLY OPERATION OF THIS PLANT. IN 1972, AN EXTENSIVE INDUSTRIAL HYGIENE SURVEY WAS CONDUCTED. MULTIPLE GRAB SAMPLES WERE COLLECTED IN IMPERVIOUS PLASTIC BAGS AND ANALYZED BY GAS CHROMATOGRAPHY. THE FOUR CONTROL OPERATOR CLASSIFICATIONS HAD TWA VALUES BETWEEN 0.2 AND 1.3 PPM. MAINTENANCE EMPLOYEES HAD A TWA VALUE OF 1.7 PPM AND THE SUPERVISORY EMPLOYEES HAD A TWA OF 1.3 PPM. THE LOADING APOOOOOf29 -16- OPERATIOMS HAD A "HI4 VALUE OF 45 PPM AMD THE LABORATORY EMPLOYEES WHO COLLECT SAMPLES FROM STORAGE TANKS HAD A TO OF M PPM. ourPersonnel monitoring is presently eeing carried on a systematic I 1973,AND PERIODIC BASIS IN THIS PRODUCTION UNIT. n ALL TO VALUES WERE BELOW ID PPM EXCEPT FOR THE LABORATORY EMPLOYEES WHO HAD TO 3DEXPOSURES OF UP TO PPM, A LEVEL WELL BELOW OUR INDUSTRAIL HYGIENE GUIDELINE OF 50 PPM, Monomer Plant HZ started operation in 1958. Limited surveys were CONDUCTED IN 1965 AND REVEALED TO'S RANGING FROM 9 TO 60 PPM. An 1973,IN-DEPTH SURVEY WAS CARRIED OUT IN ALL TO VALUES WERE BELOW 10 PPM EXCEPT FOR THE LABORATORY EMPLOYEES, THEIR VALUES WERE BETWEEN ID AND 15 PPM. #3 1969. I 1973 - 1974taoMER Plant began operation in na personnel 1 10MONITORING STUDY, TO VALUES RANGED FROM LESS THAN FPM TO PPM. O #1 1946 1972. 1950ur polymer Plant was operated from to Between and 1959 SEVERAL INDUSTRIAL HYGIENE SURVEYS WERE CONDUCTED. A NUMBER OF JOB CLASSIFICATIONS (POLYMERIZER OPERATORS, DRIER OPERATORS, MONOMER STILL OPERATORS, AND MONOMER TRANSFER OPERATORS) HAD WORKPLACE ENVIRONMENTAL 50 335LEVELS RANGING FROM TO PPM VINYL CHLORIDE. AFTER INSTALLATION OF A CONTINUOUS ANALYZER APOOOOOIJO -17- FOR THE WORKPLACE AIR IN 1959, IMPROVEMENTS WERE ACHIEVED. VlNYL CHLORIDE TO VALUES RANGED FROM 25 TO 85 PPM DURING THE PERIOD 1950-1957, Our present polymerization plant, polymer plant number two, began operation in 1955; Historically the TO values have been decreased over this period IOF TIME. n THE EARLY HISTORY, TWA VALUES OF 105-2*10 PPM WERE OBSERVED. During 1973, TO values for vinyl chloride in the air were in the 1 to 25 ppm RANGE. We emphasize that there is some VARIATION in TO VALUES from day to day FOR A GIVEN TYPE OF OPERATION. FOR EXAMPLE, OPERATORS INVOLVED IN PUMPING REACTORS SHOWED VALUES RANGING FROM 1 TO 3*1 .PPM. SIMILARLY^ THREE OPERATORS INVOLVED IN LOADING OPERATIONS HAD TO VALUES RANGING FROM 8 TO 31 PPM. We ENCOURAGE RECOGNITION THAT SUCH VARIATION WILL OCCUR IN NORMAL DAY TO DAY OPERATIONS INVOLVING TRANSFER OF MONOMER. We ARE INCLUDING REPORTS ON A NU-BER OF OUR -INDUSTRIAL HYGIENE MONITORING STUDIES AS WRITTEN SUPPLEMENTS TO THIS STATEMENT, THESE ARE LABELED Appendix II. In SUMMARY, THE INDUSTRIAL HYGIENE DATA SHOW THAT LEVELS OF EXPOSURE BELOW 90 PPM ARE ATTAINABLE IN BOTH PRODUCER AND USER PLANTS OF VINYL CHLORIDE, APOOOOOI31 18- - It must be noted, however, that with older plants the achievement OF SUCH GOALS MAY BE DIFFICULT, AND IN ALL PROBABILITY WILL REQUIRE MAJOR MODIFICATIONS THAT WILL TAKE TIME TO ACCOMPLISH, i APOOOOOf32 19- V. SAFBY IN THE VlitfL CHLORIDE INDUSTRY The operation of a safe plant involving the handling of toxic, hazardous MATERIALS REVOLVES AROUND! 1, Establishment of safe, practical allowable ENVIRONMENTAL LEVELS, 2, Implementing appropriate engineering and OPERATING PROCEDURES TO ACHIEVE OR BETTER THESE LEVELS, 3. Providing analytical monitoring capability to INSURE THE ENVIRONMENT IS MAINTAINED BELOW THE ESTABLISHED LEVELS AND TO'DETECT EXCURSIONS ABOVE SUCH LEVELS, Initiating appropriate corrective action when BREAKDOWNS OCCUR AND GUIDELINES ENVIRONMENTAL LEVELS ARE EXCEEDED, 5. Developing and supporting an appropriate medical SURVEILLANCE PROGRAM, DOW HAS A SAFETY PHILOSOPHY THAT THE SAFETY OF OUR EMPLOYEES, OUR CUSTOMERS AND OUR NEIGHBORS IS OF PRIME AND OF UTMOST IMPORTANCE. THIS SAFETY PHILOSOPHY ToPERI-EATES OUR OPERATIONS, ACHIEVE OUR GENERAL SAFETY GOALS FOR VINYL CHLORIDE OPERATIONS AND TO ACHIEVE A GOAL THAT INDUSTRIAL EXPOSURE TO VINYL AP0000013J 20 - CHLORIDE SHOULD BE KEPT BELOW 50 PPM ON A TIME WEIGHTED AVERAGE, WE HAVE IFPLEMSNTED THE FOLLOWING DESIGN AND ENGINEERING PRINCIPLES FOR VINYL CHLORIDE OPERATIONS: 1.- Processing systems are closed.with no open vessel OPERATION, 2, Current buildings where vinyl chloride is manufactured OR POLYMERIZED ARE OPEN TO THE ATMOSPHERE OR HAVE VENTILATION TO MINIMIZE CONCENTRATION BUILD-UPS. 3. Engineering design emphasizes reasonable process AUTOMATION AND REASONABLE REMOTE OPERATION IN ORDER TO MINIMIZE PERSONNEL EXFOSURE, 4, Vent exhaust systems are selectively located to - 5, MINIMIZE THE POSSIBILITY OF PERSONNEL EXPOSURE. The number and quantity of samples for control analyses are minimized. Careful application of the above principles has led essentially to the attainment of our GOAL OF M VALUES of less THAN 50 PPM IN our operations. We BELIEVE THAT GOOD OPERATING PROCEDURES MUST BE TAILORED TO EACH SPECIFIC PLANT, THAT PLANT SIZE, AND THE NATURE OF THE PROCESS AND PLANT LOCATION ALL WILL INFLUENCE THE EXACT PROCEDURES TO BE CARRIED OUT, I WILL MENTION APOOOOOf34 21- - A PEW OF THE r"DRE IMPORTANT OPERATING PROCEDURES ANO TECHNIQUES INVOLVED FOR ONE OF OUR I'ONOTER PRODUCTION PLANTS TO ILLUSTRATE THE COMPLEXITY OF GOOD PLANT OPERATION, If Employees are familiarized with emergency procedures AND SIGNALS; FOR EXAMPLE, WIND DIRECTIONAL SIGNALS, HORN EMERGENCY CALLS, AND EVACUATION ROUTES. 2. Collection of analytical samples of vinyl chloride FROM STORAGE TANKS INVOLVES A CLOSED LOOP SAMPLING SYSTEM IN ORDER TO RETURN VINYL CHLORIDE TO THE PROCESS RATHER THAN VENTING VAPOR IN THE WORKPLACE ENVIROfvMEJTT. LABORATORY SAMPLES OF VINYL CHLORIDE ARE HANDLED IN HOODS AND SAMPLE CYLINDERS ARE GROUNDED WHEN DISCHARGED, On-LINE GAS CHROMATOGRAPHY IS BEING USED EXTENSIVELY TO MONITOR PRODUCT PURITY AND PROCESS OPERATION; THIS HAS REDUCED MARKEDLY THE NUMBER OF MANUAL SAMPLE COLLECTIONS REQUIRED, 3, Specially designed vapor equalizing lines CONNECTED BACK TO THE STORAGE TANK ARE EXPLOYED IN THE LOADING OF TANK CARS, *i, Environmental monitoring of air is being conducted BY A NUMBER OF TECHNIQUES. GAS DETECTOR ALARMS ARE LOCATED. THROUGHOUT THE PLANT AT A NUMBER OF STRATEGIC AP00000135 22- - locations TO WARN OF ANY FLAW-ABLE CONCENTRATIONS, Ratable detector instruments are available for CHECKING PLANT AREAS OR PROCESS EQUIPMENT PRIOR AlRTO NON-ROUTINE OPERATIONS AND PROCEDURES, QUALITY SURVEYS WERE CONDUCTED IN MONOMER PLANT number 1 in 1971, During the first quarter of 121974, A CONTINUOUS ANALYZER SYSTEM FOR STRATEGIC LOCATIONS IN THE PLANT WILL BE INSTALLED. THIS WILL PROVIDE CONTINUOUS BACKGROUND INFORMATION AND PROVIDE INSTANTANEOUS SIGNALS FOR ANY UN USUALLY HIGH CONCENTRATIONS THAT MIGHT OCCUR DUE TO LEAKS, SPILLS OR OTHER NON-ROUTINE SITUATIONS, ' In our polymerization operations, we have not had problems of worker ILLNESS FROM THE CLEANING OF POLYMERIZATION VESSELS, Vfe UTILIZE HIGH PRESSURE WATER JETS AFTER EACH POLYMERIZATION REACTION TO PREVENT POLYMER BUILD-UP, Our EMULSION POLYMERIZATION KETTLES REQUIRE MANUAL CLEAN-OUT EVERY TWO OR THREE MONTHS, AFTER WATER CLEANING OF THE VESSEL, ALL LINES ARE BLANKED TO PREVENT ANY MATERIAL FROM ENTERING THE VESSEL; THE ATMOSPHERE * IS TESTED FOR OXYGEN SUPPLY, AND A CONTINUOUS VINYL CHLORIDE MONITORING PROBE IS PUT INTO THE VESSEL, CONCENTRATIONS MUST BE BELOW 50 PPM PRIOR TO VESSEL ENTRY. AlR PURGE IS MAINTAINED ON THE VESSEL DURING THE CLEANING OPERATION. * AP00000136 25- - VII tfi/miCAL fEIHODOUDGY Four methods are available for environmental monitoring of air for THE PRESENCE OF VINYL CHLORIDE; 1. COWJUSTIOT^CONDUCTIVITY 2. Gas chromatography 3. Infrared spectrophotometry 4. Flame ionization spectroptSDTometry Gas chromatography is very specific, but requires about 10 minutes PER SAMPLE, Flame ionization detectors have no specificity-responding TO ALL CARBON-CARBON OR CARBON-HYDROGEN BONDS, BUT ARE PORTABLE AND THE MEASUREMENT IS INSTANTANEOUS. THE COMBUSTION-CONDUCTIVITY METHOD RESPONDS TO ANY MATERIAL WHICH BURNS TO PRODUCE IONS. Tt RESPONDS RAPIDLY. INFRARED ANALYZERS ARE VERY SPECIFIC, RESPOND QUICKLY AND ARE PORTABLE. ALL OF THESE TECHNIQUES HAVE ADEQUATE SENSITIVITY, DETECTING CONCENTRATIONS OF 1 PPM. e PERSONNEL MONITORING IS ACHIEVED THROUGH USE OF ABSORPTION TUBES FILLED WITH .ACTIVATED CARBON. THE ABSORBED CHLORINATED HYDROCARBONS ARE DETERMINED BY GAS CHROMATOGRAPHY AFTER THERMAL RELEASE OR EXTRACTION BY CARBON DISULFIDE. At Dow, most of our environmental monitoring has been with combustion- conductivity ANALYZERS. We HAVE USED THESE ANALYZERS FOR CONTINUOUS MONITORING SINCE 1959 WITH EXCELLENT RESULTS. * * AP00000137 VII, RECGtEOTIOMS FOR GOVERTJiHfJT-IiflDUSTRY ACTION OSHA1, to URGES TO RECOGNIZE TOE VOLUNTARY INDUSTRY ACTION TO LOWER TOE LEVELS OF EXPOSURE TO VINYL * CHLORIDE AND TOE LEAD ROLE OF INDUSTRY IN OBTAINING DATA ON THE VINYL CHLORIDE PROBLEM. 2, DOW BELIEVES TOE INDUSTRY RECOGNIZES TOE NEED TO OSHAMAINTAIN ENVIRONMENTAL LEVELS BELOW THE STANDARD AC6IHOF 500 PPM AND EVEN BELOW THE RECOMMENDATION OF 200 ppm, 3, to BELIEVES THAT IT IS INDUSTRY-'S AND GOVERNMENT'S RESPONSIBILITY*TO INFORM ALL EMPLOYEES OR PERSONS WORKING WITH VINYL CHLORIDE ABOUT ITS HAZARDS AND TO DEVELOP AND IMPLEMENT TRAINING PROGRAMS TO HELP PREVENT OVER EXPOSURE AND INSURE PROPER REACTION IN EMERGENCY SITUATIONS. WE BELIEVE INFORMED-EMPLOYEES WILL CO OPERATE IN ELIMINATING OVER- EXPOSURE AND SUGGEST METHODS FOR IMPROVEMENT. 4, ' Based upon the medical and toxicological data available TO US AT THIS TIME, DOW BELIEVES THAT AN EIGHT-HOUR TO OF 50 PPM IS a SATISFACTORY ENVIRONMENTAL STANDARD FOR VINYL CHLORIDE. APOOOOOt 38 -25- DoW IS SUPPORTING AND ACTIVELY COOPERATING IN LONG-TERM INHALATION, METABOLISM AND EPIDEMIOLOGICAL STUDIES IN ORDER TO OBTAIN THE MOST PRECISE DATA POSSIBLE RELATING TO THE POTENTIAL FOR OCCUPATIONAL HEALTH ASSESSMENT. (A) WE WILL STRONGLY SUPPORT INDUSTRY-GOVERNMENT EVALUATION OF THE DATA AS IT BECOMES AVAILABLE. (b) Results of the epidemiological survey of vinvl CHLORIDE WORKERS INITIATED ABOUT A YEAR AGO BY MCA VIA CONTRACT WITH TABERSHAW"CoOPER WILL BE AVAILABLE IN THE NEAR FUTURE, It SEEMS REASONABLE TO EXPECT THAT THESE RESULTS WILL PROVIDE ` ADDITIONAL AND SUBSTANTIVE BASIS FOR RULE-MAKING. DOW BELIEVES RULE-MAKING SHOULD NOT BE BASED ON CONDITIONS THAT EXISTED IN THE PAST BUT SHOULD BE BASED ON CONDITIONS NIOSHAS THEY EXIST TODAY. BASED ON ACTIVITY AND ON WIDESPREAD VOLUNTARY ACTIONS BY INDUSTRY; WE BELIEVE THERE IS NO NEED FOR A TEMPORARY EMERGENCY STANDARD, REALISTICALLY; WE BELIEVE A TEMPORARY EMERGENCY STANDARD WOULD RESULT IN POLARIZATIONS RATHER THAN CONSTRUCTIVE DEFINITION OF AREAS OF CONCERN AND CONSTRUCTIVE PROBLEM SOLVING, APOOOOOI39 -26- We believe mST producers/users of vinyl chloride have or VERY SOON WILL HAVE THE CAPABILITY TO MAINTAIN AN EIGHT- (TV/A) 50HOUR TIME-WEIGHTED AVERAGE OF PPM OR BELCW, THERE FORE WE SUGGEST THAT STEPS BE TAKEN IN ORDER TO DEVELOP THE STANDARD IN A REASONABLE WAY. (a) In order to assess the state and magnitude OF THE PROBLEM, WE SUGGEST THAT EACH PRODUCER/USER OF VINYL CHLORIDE COMPLETE AN INDUSTRIAL HYGIENE. SURVEY OF HIS OPERATIONS AND A MEDICAL SURVEY OF VINYL CHLORIDE WORKERS WITHIN THREE. MONTHS AND REPORT THE RESULTS OF EACH SURVEY TO NIOSH/OSHA, I TWA'S 50(b) f THE SURVEY REVEALS IN EXCESS OF PPM, THE MANUFACTURER OR PROCESSOR SHOULD IMMEDIATELY TAKE STEPS TO REDUCE EXPOSURE BY OPERATIONAL AND/OR ENGINEERING CHANGES AND REQUIRE THE USE OF APPROPRIATE RESPIRATORY PROTECTION BY HIS EMPLOYEES LIKELY TO BE EXPOSED TO SUCH LEVELS. (c) IF THE MEDICAL SURVEILLANCE PROGRAM INDICATES ABNORMALITIES THAT COULD BE ATTRIBUTED TO EXCESSIVE EXPOSURE TO VINYL CHLORIDE OR A CONDITION THAT COULD REASONABLY BE EXPECTED TO BE AGGRAVATED BY CONTINUED AP00000140 WORK WITH VliJYL CHLORIDE, THAT PERSON MIGHT WELL BE REMOVED TO ANOTHER JOB NOT INVOLVING W NIOSHSUCH EXPOSURE* , e RECOM-cND ASSISTANCE IN DEFINING THE PRIORITY OF HEALTH PARAMETERS . ` FOR STUDY, Dow OSHA'ssupports establishment of a permanent health standard FOR VINYL CHLORIDE BY REGULAR RULEMAKING PROCEDURES. We- recommend that the standard state what should be accopflished. LEAVING THE "hOW-TO-ACHIEVE COMPLIANCE" TO INDIVIDUAL PLANT IMPLEMENTATION. j AP0000014I