Document LKG7rZqnXBg0MzVb6RJMnwxzg

/ Pyrolytic Evaporation of a Plasticizer from Polyvinyl Chloride Meat Wrapping Film by Rudolph J. Jaeger Department of Physiology kresge Center for Environmental Health Harvard School of Public Health Boston, Mass. 02115 and Ronald A. Hites Department of Chemical Engineering Massachusetts Institute of Technology Cambridge, Mass. 02139 Recent interest in the environmental and health effects of plasticizers from polyvinyl chloride (PVC) formulations has cen tered around the reports of STALLING et^ al^ (1973) and JAEGER et al (1973, 1972). In these reports, tissues from fish and humans have been found to contain the plasticizer, di-2-ethylhexyl phthalate fDEHpl). Tn the case of human tissue, the contamination presumably resulted from the administration of blood which was stored in pvc plastic. In another report (JAEGER, 1971), another plasticizer, di-2-ethylhexyl adipate . (Deha1) was foun'1. to be extracted by human blood from PVC tubing. In still other reports in the popular press, plasticizers fron PVC have been imp.1 icated in the "new car smell". However, with the exception cf unpublished work-currently in progress, little information is available to demonstrate the safety or hazard of Pvc plasticizers which may contaminate the internal or external environment. An unpublished report (VANDERVORT, 1971) from the Bureau of Occupational Safety and Health (NIOSH-USPHS) has concerned itself with the pvc film used to wrap meat. This Work which is ongoing was begun as a result of workers! complaints of lung, throat and eye irritation during the heat cutting and sealing processes used to wrap meat. In the preliminary communication cited above, it was stated that chlorobutane, benzene, toluene, l-chloro-2-ethyl hexane, 2-ethyl-l-hexanol, benzyl chloride and hydrogen chloride were released from the PVC film when it was heated to 200 C (app. 400 F) . The present report was conducted as a result of litigation involving a manufacturer of PVC plastic food wrap. In this case the worker's complaints were similar to those cited above. Add itionally, the worker noted an oily material in the vicinity of the meat wrapping machinery. An investigation was begun to de termine if the plasticizer in the PVC wrap was DEHA, and to de termine if this material would evaporate from the film when it was heated. ^DEHP and DEHA are frequently and erroneously referred to as DOP and DOA. 45 HuHWin Eniironmrntj! Cnnttmiriitinfi A Vwl II, No, 1 0 1971 by ^priuuer*Vfrlkj; New York liu1. BOR 011564 MATERIALS AND METHODS A sample of PVC food wrap was obtained from the Boston office of the manufacturer. A 10 g sample was inserted into a one inch glass tube of sufficient length to act as an air conden ser. The glass tube had previously been cleaned with dichromate solution and rinsed with regent grade acetone. Plugs of acetonewashed glass wool were tamped on either side of the PVC sample, and the entire assembly was placed in a tube furnace that had previously been heated to 400 F. Air from a compressed air tank was passed down the tube, and allowed to escape on the other side of the furnace. The material was heated for 1.5 hr. at 275-350 F. During this time, a brown oily liquid was observed to collect in the condenser. At the same time, an acrid gas was released (presumed to be HC1). The oily liquid was collected in acetone by careful washing of the distal end of the glass tube-air condenser. No attempt was made to quantify the volume released from the 10 g sample of PVC film nor were attempts made to recover more volatile materi als such as reported by VANDERVORT (1971). The recovered acetone soluble material was analyzed in a Varian 1700 gas chromatograph (GC) equipped with a flame ioniza tion detector, a 3 ft. column (stainless steel, 1/8 inch) pack ed with 5% SE-30 Ci'i Gas Chrom Q (80-100 mesh) was employed. Nitrogen was the carrier gas and the oven .temperature was 250 C. An acetone extract of the PVC_film was made. The manufact urer confirmed rhe plasticizer to be DEHA. Samples of the acetone extract cj. the film and the pyrolytically evaporated material were submitted for computerized, combined gas chromato graphy, mass spectrometry (GC-MS). RESULTS AND DISCUSSION FIGURE ONE 46 BOR 011565 In figure one above, the results of the 3 GC determinations are shown: A represents acetone alone; B represents the acetone extract of the PVC film; C represents the GC pattern of the material recovered from the pyrolytic distillation of the PVC film. Since the manufacturer stated that the plasticizer shown by B is DEHA, and the retention time of B and C are similar, the data suggests that DEHA does, in fact, pyrolytically eva porate from PVC food wrap. To confirm the supposition of identity, the material from C was analyzed by GC-MS. The data is shown in table one. The information is derived from computer analysis of the MS output. The spectrum of relative intensity for each m/e value can be read as follows; m/e is represented by the- arithmetic sum of the value given at the top of the column plus the value shown at the left of the row. The intensity corresponds to the value shown at the intersection of the row and column for each ra/e value. The spectrum shown below is consistent with the published spectra of DEHA. The GC retention time was also con sistent. The characteristic masses are m/e of 129 (intensity99) , 147 (17), and 112 (24). The species at m/e 129 is the protonated anhydride of adipic acid. TABLE ONE Mass Spectrum 20 34 48 62 76 0 0000 1 0013 2 1 001 3 111 4 1000 5 4132 6 224 7 16 26 9 21 8 5 13 33 11 9 20 44 37 3 10 1 7 2 2 1 11 1 1 3 13 6 12 1 1 0 13 ___Q_--1___ L_ 0 90 104 118 132 0 00 2 112 10 00 10 14 10 01 110 1 2 10 0 2 21 00 1 24 00 1 14 11 6 14 3 8 1 99 1 30 90 _1_____1 2 0 146 2 17_ 2 2 1 0 0 0 0 0 0 1 1 0 160 174 138 202 10 00 00 0Q 0 111 0 00 11 18 00 02 00 12 1 00 00 31 00 01 0 10 00 00 0 0_______ This demonstration of DEHA release from PVC film under con ditions which approximate use should be carefully considered. The previous report by VANDERVORT (1971) in conjunction with the observations reported above suggest that additional investiga tions should be undertaken^. There exists a possibility for 2 Dr. Vandervort, in a personal communication, has confirmed the presence of DEHA as a pryolysis product from PVC film. A more complete report including a safety evaluation of the material is currently being prepared by NIOSH. 47 BOR 011566 interaction between the plasticizer and ther decomposition pro ducts. Such a possibility may c mpound the slight hazard asso ciated with the irritation observed by workers who must use the material. Certainly long term investigations under conditions of m* are indicated. A complete evaluation of pulmonary func tion in workers with a predisposition to respiratory complica tions would be a minimum prerequisite. ACKNOWLEDGEMENT The authors wish to acknowledge the help of Prof. W. A. Burgess and Mr. J. Lynch. Thanks also to Mr. Max Dean for bringing the problem to the authors' attention. BIBLIOGRAPHY JAEGER, R. J., and R.J\ RUBIN: Env. Health Perspec. 1_, 95 (1973). JAEGER, R.J., and R.J. RUBIN: NEJM 287, 1114 (1972). JAEGER, R.J.: Ph.D. dissertation Johns Hopkins University, Balti more, Maryland (1971). STALLING, D.L., J.W. HOGAN, and J.R. JOHNSON: Env. Health Perspec. 1^, 159 ' (1973) . VANDERVORT, R.: Unpublished report entitled "Polyvinyl Chi rid* Meat Wrapping Film Study" U.S. Dept/ HEW, PHS, BOSH D\v. Occupa tional Injury and Disease Control, 1014 Broadway, Cincinnati, Ohio, 45202, (1971). 48 BOR 011567