Document 1geaNeJVbMXe1vYJmJLEmaZvd

Mar 1980 Volume 44 Number 3 0^ iH Industrial Health Foundation, Inc. 5231 Cant re Avenue Pittsburgh, Pennsylvania 15232 INDUSTRIAL HYGIENE DIGEST NEWS ITPtS 4B4/8DS Dr. Maltonl Reports Tumors In Rats at Still Lower Levelsof Vinyl Chloride. Occur* Health k Safity Letter lpl J-4, March 22* 19^0. Dr* csar* Ktlteni of Italy* whose earlier studies, on vinyl chloride exposure figured promi nently In the OSHA standard, now reports that tumors have begtt found in laboratory rats ex posed to as low as 25 ppa of vinyl cMerlde and possibly 10 ppm. At a nesting ealled by OSliA, NIOSH and NIEHS to hear and evaluate new data on vinyl chloride for standard-setting purposes. Dr. Maleoni made ths following point*: (1) In experiaental animals, principally Sprague-Dawlsy rats but ineluding ether species at veil, tumors have been found st progres sively lower levels of vinyl chloride exposure--in s few cases almost down to 1 ppm. All of the animals were permitted to live a lifespan, none being sacrificed. Newborn rats were specially sensitive. (2) Tumors were found not only In the liver bur also in the brain, Jung, kidneys and other organs. Dr. Maltonl said this result showed that workers exposed tn vinyl chloride should b* nonitoted not only for livsr damage, including angiosarcoma, but for other organs as well. In addition to the tumors, etnesr precursor dysplasias were found in - the liver* of-many-animals. (3) Significant levels of tumors were frnnd in- ths rnts-at 50 ppm at various durations of exposure In what Dr. Maltonl believed was a significant doseresponse relationship. Many in the audience took issue with hr. Hnlti'cif** findings. Icr example, Dr. V. Clark Cooper of Berkeley noted that workers exposed to vinyl clilorldi hive been monitored for multiple tlLcs for a mimht-r of year?. In his own present .it ion, 1'r. tooper extended the earlier studies of Mrs. Taborshnv and Gaffuy which Indicated some exces* -! cancer Ji-alhs in worker* exposed to vinyl tlihuide but curio to no crnclusirn on a cuuf..l relationship. In his analysis,* in which 3,Q00 additional workers were evaluated in Otlow- ups, the total number of deaths increased from 343 to 707, with some lucre.t*i in cancor? of the digestive tract, central nervous system and some In the respiratory tract . Rut Dr. Cooper said that, if anything, his analysis was even mere Inconclusive on causal relation ships with vinyl chloride. --Condensed front text 48S/60x Vinyl Chloride Detector Sensitive to Belov nob. Chem. A Eng. hews ,58: 43, April 7, I960. The ability to detect traces of vinyl chloride has been extended a thousandfold to measure levels below parts per billion, report scientists at the University of Colorado and national Oceanic A Atmospheric Administration Aeronorav Laboratory in Boulder. The development depends on a conventional nickel-63 electron capture detector in which the nitrogen carrier pas is doped with nitrous oxide (N.0). The "dramatic improvement" in sensitivity la due to a reac tion In the detector of vinyl chloride with 0", which forms when nitrous oxide reacts with electrons at 350* C. Because of the high sensitivity, air samples could he colloitoil lu cignrotIc-pnck-sised devices worn by workers. If applied, the method could eliminate ".ill of the complex handling, storage, and desorption procedures" now being used to measure vln"l chloride In Industrial settings. --Text reprinted AM/Btix Polychlorinated Biphenyls (PCBs)i Finn! Amendment to the Disposal Requirements for PCB Canaclters In ClKUhai Waste Landfills. Environmental Protection Agency. Fed. Reg. 45: 20473-20475. March 26, 1960. Action: Final rule. On Xovember 21* 1979 EPA requested content on a proposed nnendment modifying the disposal provisions of the PCB regulation (43 FR 7150, February 17, 1976; superseded by 44 TO 31514, May 31, 1979). The November amendment proposed to extend the deadline for allowing disposal of large TCB capacitors in chcmicsl vsste landfills from January t, 1980 to thirty days after EFA announced that an Annex 1 incinerator vat approved and operational for disposal of PCB capacitors. Tluit amendment is being promulgated hy this notice with certain modifications. First, fFA is creating small TCB capacitor* owned hy manufacturers of Pen capacitors or equipment the same as large PCS capacitor* for purposes of disposal. Second, IFAvill permit disposal of capacitors in ohemiral waste landfills until March 1, J^KI. Third, the Assistant Ailmitiifttrater for Pesticides and Toxic Substances wv authorise the reopening of fhoitlr.il waste landfills after March 1, 1981, for disposal of PcB capat-ilors under *picified condition*. Fourth, F-PA will require all I'C* capacitors to he containiTired and packed with adsorbent nutcrinl prior tn their disposal in a chemical waste landfill. Effective March 28, 1980. --Summary 1 l AP00022024 AP00022025 ^fAbout This Pamphlet , .^^The purpose of this pamphlet is to ijUtf^give employees as well as the gen- ^#lral public, an overview of the dan&|'iggers involved-in wofking with vinyl ^gichloriclo (VC) and to explain the * L^^OSHA standardsthat apply to its use \vK-!P the workplace. ' Vmyi chloride is the basic ingrec^^dient in making polyvinyl chloride (PVC), which is used in about 55 , '^percent of today's plastic products. :-g^&As such.it is an important element in ^?7today's technology and economy. It 3rt & possible to work with these sub' ^ySlances in a manner that will not ,. cause illness. But doing so requires JgFaian understanding of the hazards in- ^J-volved and of the measures neces..^^jsary to eliminate or reduce these '^hazards. The following pamphlet contains > s-8eneral information only. It should be considered a substitute for .** any of the provisions of the Occupa- ' ^tlonal Safety and Health Act or for > any regulations issued by the U. S. >-* Department of Labor's Occupa^wtional Safety and Health Administra tion. -w*./*.-.^.~r- *** -B ^ -ti * 'ih + '-ry/.,^"1 : :{|* 'A'-votj- .V^V:;.\ ' ,7. .. \ yf ' ' ^ i -V- . AP00022026 Vinyl Chloride Job Health Hazard Series U.S. Department of Labor Occupational Safety and Health Administration June 1975 OSHA 2225 V AP00022027 r AP00022028 Endangered Workers Mostjob health hazards--such as lead, mercury, and silica--have been recognized for decades orcenturies. But vinyl chloride, a gas used in the production of more than half of today's plastic prod* ucts. has only recently been shown to be highly dangerous. Until January 1974, the gas was generally considered of low toxicity. Then it was found to cause a rare form of cancer of the liver--angiosarcoma--which cannot be diagnosed until it is incur* able. Vinyl chloride (VC), which has always been handled with rela tive care, since it is both explosive and highly flammable, is the basic ingredient in making polyvinyl chloride (PVC). PVC is all around us. The chances are you ride to work on a vinyl seat, walk across vinyl-tiled floors on PVC-soled shoes, eat sandwiches wrapped in PVC from a vinyl tablecloth, relax to the sound of PVC records, infants suck on PVC pacifiers. Although studies are continuing in both government and private laboratories, no one has yet discovered any danger in these finished products. By the time the plastics reach this stage, most of the vinyl chloride has been chemically locked into the PVC and wilt not come out again. The danger comes during the production process. Three basic steps are necessary to the production of vinyl products. First the vinyl chloride, or "monomer," is produced in a closed process, usually involving a reaction between ethylene and chlorine. The VC monomer is shipped as a compressed, liquefied gas to plants that produce the PVC resin. Batches of VC are "polymerized" by mixing them with catalysts in giant vats or reactors. After drying, the PVC resins are compounded by the addition of stablizers, lubricants, and plasticizers. Before being shipped to fabrication plants, the resin may be converted to pellets, powders, pastes, or film. The fabrication end of the PVC industry covers a huge range of processes in which the PVC is turned into its myriad of finished products. In the United States there are 15 monomer plants employing about 1,000 workers, 36 PVC plants with 5,600 workers, and some 7,500 fabrication plants with about 350,000 employees. At each stage there are certain potential trouble spots where the VC gas may escape into the air and reach the workers. Both monomer and polymerization plants face the problems of random leaks from pump seals, compressors, valves, gaskets, and storage tanks. Both must also deal with reducing the amount ofthe gas that escapes during quality control sampling. During loading or unloading of the monomer, tank car workers may be exposed to high concentrations In the air. Because of the danger from fire and explosion, the plants are usually spread over sites of several acres, with the result that the VC gas is not confined to small areas, but often can be found in low levels throughout the plant. Most plants that produce the basic monomer are open-air opera tions and generally have lower concentrations ofgas in the air than polymerization plants. The highest exposures in the entire industry apparently are those experienced by the workers who climb into the polymeriza tion vats or reactors to chip out the PVC residue. In the past, these cleaners were surrounded by concentrations as high as 1,600 parts of VC per million parts ofair; exposure levels for reactor cleaners still may reach 500 parts per million (ppm). Fourteen of the 16 men who have died from VC-related angiosarcoma in the United States had, at one time or another, been vat cleaners. By the time the PVC reaches the fabricating plant, the danger is the small amount of VC gas that was not chemically locked into the PVC. These may leak out ofthe PVC in processing or handling. The fabrication procedures that hold the most potential for expo sure involve mixing and heating the resin, as in extruding PVC around an electrical wire. The heat may drive offany remaininggas into the workplace air. ,, What It Can Do to You In addition to the danger of angiosarcoma of the liver, recent studies ofworkers exposed to VC show that they have higher than normal rates of cancer of the lung, brain, and bone marrow. Suicide rates were found to be twice normal in one study of 161 workers in a Kentucky plant. Vinyl chloride's attacks are slow; the cancers, for example, may not show any symptoms until 15 years after the beginning of a worker's exposure. Prevention of Vinyl Chloride Poisoning The basic protection from VC must come from engineering con trols; avoiding leakage of the gas into the air. Under the Occupa tional Safety and Heahh Act, this is the responsibility of em ployers, many ofwhom have expresse d doubts about being able to meet the stringent OSHA standard ofone part per million ofVC in the air, averaged over an 8-hour day, with a maximum peak of five ppm. If these limits are not met, employers must reduce exposures to the "lowest practicable level,'' and personal respirators must be made available to the employees who are exposed. In certain situations, employees have a choice as to whether or not to wear respirators. Until April 1, 1976, a worker can decline to wear a respirator when the VC concentrations are above one ppm Nit not above 25 ppm. Federal Standards for Vinyl Chloride Exposure The OSHA standard for vinyl chloride exposure, although prom ulgated in October 1974, to take effect January 1, 1975, was held in abeyance pending action on a suit brought by the plastics manufac turers. Under a decision by a special three-judge panel of the United States Second Circuit Court, the standard went into effect April 1,1975. The plastics manufacturers have indicated that they intend to appeal this decision to the U. S. Supreme Court. The standard applies to the "manufacture, reaction, packaging, storage, handlingor use of VC and PVC'' but not to the handlingor use of finished PVC products. PVC is considered a "finished product" when it has passed through all production steps that involve mass melting. The standard, for example, would cover such operations as molding, extrusion, banbury mixing, and calendering. It would not cover thermoforming or blister packag ing. Although the standard sets an air concentration limit ofone ppm of vinyl chloride on an average over an 8-hour workday, and a five ppm allowable peak exposure, it sets no deadlines for manufactur ers to reach such levels. The technology involved is too uncertain. But the employers must draw up plans for reaching the standard levels, and make those plans available to OSHA. Because of the wide variety of types of plants involved in polyvinyl chloride production, the concept of an '`action lever* has been made part of the standard. If a fabricating plant tests its air and finds that VC levels are less than 0.5 ppm ("action level"), the plant is effectively exempted from much ofthe rest of the standard. If less than 0.5 ppm is in the air, the employer is exempted from further monitoring unless changes are made in the processing, or there ts other reason to believe the levels may have risen. When the monitoring reveals VC levels above one ppm, the employer must set up a regulated area within the plant--that area in which the dangerous amounts are found--and restrict it to "authorized personnel." A daily roster ofSuch persons within the area must be maintained. Employees must be informed ofthe cancer risk associated with VC, instructed in the proper use ofrespirators, and made aware of work practices that could release dangerous quantities ofthe gas. All employees exposed to levels higher than 0.5 ppm, whether they wear respirators or not, must be given free medical examina tions, including blood tests, once a year. Workers with more than. 10 years exposure must be examined every 6 months. Records ofexposure must be kept for at least 30 years, and the results made available to employees or their authorized represen tatives. Medical records must be held 30 years; or20'years after employment, whichever is longer. Copies of medical records must be furnished to a physician on request of the employee. Warning signs in regulated areas and labels on VC and un finished PVC containers must include the words "cancer-suspect agent." u.s. department of labor Regional Offices for Occupational Safety and Health REGION I <CT, ME, MR, NH, A1, VT) 18 Oliver Street Boston. MA 02110 Telephone: (617) 223*6712 REGION II (NY, NJ, PH, VI, CZ) Room 3445, 1 Astor Plaza 1515 Broadway New York. NY 10036 Telephone: (212)971*5941 REGION III (Dfc DC, MD, PA, VA, WV) 15220 Gateway Center 3535 Market Street Phiiadephla, PA 19104 Telephone: (216)597*1201 REGION IV (AL, PL, GA, KY. M3. NC, SC, TN) 1375 Peaehtree Street. N.E. Suite 567 Atlanta, GA 30309 Telephone: (404) 526*3573 REGION V (IL IN, MN, Ml, OH, Wl) 230 South Dearborn 32nd Floor Chicago. IL 60504 Telephone: (312) 353*4716 REGION VI (AR, LA, NM, OK, TX) 555 Grilfin Square Room 602 Dallas, TX 75202 Telephone: (214) 746*2477 AP00022033 REO ION VII (IA, KS, MO, NE) 911 Walnut Street, Room 3000 Kansas City, MO 64106 Telephone: (616) 374-5661 REGION VIII (CO, MT, NO, SO, ITT, WY) Room 15010, Federal Bldg. 1961 Stout Street Denver. CO B02O2 Telephone: (303) 837-3883 REGION (X (CA, AZ, NV, HI) Box 36017 450 Golden Gate Avenue San'Francisco, CA 94102 Telephone: (415) 556-0586 -- - REGION X(AK, ID, OR, WA) Federal Office Bldg., Room 6046 909 First Avenue Seattle, WA 98174 Telephone: (206) 442-5930 AP00022034