Document zz8goMO329ZD1n3YLKb2D0NNR

ENCLOSURE I law omcts Keller and Heckman 1180 IT1" STRUT. N.W. 4* SUITS lOOO WASRINOTOK. D.C. 90006 TtlA * ! (SOS) 49M100 CMMMMHN'-UUiir (202) 457-111 August 12, 1985 Bruce H Borsuk Vista Polymers, Inc. Vista Chemical Company 15990 North Barker's Landing P. 0. Box 19029 Houston, Texas 77224 Road Ret PDA Status of PVC Resins Dear Brucet In your July 9, 1985 letter and subsequent telephone call on July 18, 1985, you provided information concerning the formulations for Vista's PVC Resins 5265, 5305 and 5385, and requested an opinion concerning their Pood and Drug Adminis tration (PDA*) status. These resins are intended for use in various food and drug packaging applications. ve have analyzed the information provided and, as discussed more fully below, we have no hesitation in providing our opinion that these products may be used as Intended and that such use may properly be said to be in compliance with the Federal Food, Drug, and Cosmetic Act ("Act") and all applicable Food Additive Regulations. A. Regulatory Background To put our opinion into perspective. It may help to review the legal/regulatory background applicable to food con tact substances. Section 201(s) of the Act defines a "food additive" in pertinent part ass [A)ny substance the intended use of which results or may reasonably be expected to result, directly or indirectly, in its becoming a component or otherwise affecting the charac teristics of any food ... if such substance VEV-l44511 A Bruct H. Borsuk August 12, 1985 Page 2 Keller A*m HEcrtAJ-r is not generally recognized . to be safe under the conditions of its intended use; except that such tern does not include-- *** (4) any subtance used in accordance with a sanction or approval granted prior to the enactment of this paragraph pursuant to this Act. This definition is repeated in section 170.3(d) of the Food Additive Regulations which adds, again in relevant part, the following explanatory information: A material used in the production of containers and packages is subject to the definition [of "food additive"] if it may reasonably be expect ed to become a component . . directly or indirectly of food packed in the container* . ... If there is no migration of a packaging component from the package to the food, it does not become a component of the food and thus is not a food additive* Thus, a substance that is reasonably expected to become a component of food when employed in a food contact application must be (a) the subject of an applicable Food Additive Regula tion, (b) the subject of a prior sanction or approval, or (c) deemed generally recognized as safe (GRAS) If the sub stance is not reasonably expected to become a component of food under the intended conditions of use, it is not a food addi tive, and it may be so employed without any prior action by or consultation with the Food and Drug Administration (FDA). As further background Information, Food Additive Regu lations are all issued on the premise that substances must be evaluated (and cleared where appropriate) on a generic rather than a proprietary basis. In the case of plastics resins, as long as the basic resin is: (a) listed in a regulation or otherwise cleared, (b) manufactured in accordance with good manufacturing practices, and (c) complies with applicable extraction requirements, then the resin is covered by that VEV-144512 rr Bruce H. Borsuk August 12, 1985 Page 3 Keller AMS Heckmah regulation--even though different manufacturers may make the resin by different processes. FDA stated many years ago that a "basia-ttsin" is the material that comes out of the polymerisation kmjKle, i.e.* a' basic resin is the product that results when tlwXolymerization process has been carried to commercial collation. Substances such as catalysts, chain regulators, chain transfer agents, and all other materials required to produce the basic resin are considered part of the basic resin and not subject to indepen dent regulatory consideration. Thus, the clearance afforded the basic resin automatically clears those substances which are necessarily used during the polymerisation stage to produce it. We are enclosing relevant portions of a report to the Food Packaging Materials Committee ("FPM") of The Society of the Plastics Industry, Inc. (SPI), in December of 1966. The report covers a presentation by an FDA spokesperson to the FPM Committee in which the "basic resin" doctrine was set forth. The basic resin doctrine merely reflects the practical reality that FDA1could never hope to write generic regulations for food packaging materials that describe and specifically clear every substance that might properly be a component or contaminant of the packaging material as a result of every con ceivable manufacturing process that yields a suitable resin. Since trace quantities of these "unregulated" substances are not perceived to present a public health hazard, FDA has wisely chosen not to subject such substances to the burdensome pre clearance provisions of section 409 of the Act that apply to food additives. On the other hand, the basic resin doctrine does not apply to those substances added to the basic resin in order to prepare a technologically useful plastic packaging material. Thus, stabilizers, plasticizers, pigments, lubricants, and the like, which may be added to a basic resin in order to facili tate its processing or to affect the technological properties of the final plastic product, must be considered as matters separate from the clearance afforded the basic resin. YEU-144513 Bruce H. Borsuk August 12, 1985 Page 4 Kzt.lkr and Heckman B. FDA Status of Vista PVC Basins Turning now to a consideration of the specific formula* tions for Vista Resins 5265, 5305 and 5385, we note that the three products are each comprised of greater than 99 weight percent of PVC basic resin along with fractional percentages of calcium stearate and antioxidants. The formulations for the three PVC resins vary only in the ratio of reagents used and ^he specific initiator and suspending agents employed. The antioxidants used are butylated hydroxytoluene (BBT) and/or Irganox 245. Also, odorless mineral spirits may be added and subsequently removed during polymer finishing to provide cer tain property advantages. The major component of these formulations, polyvinyl chloride ("PVC") is prior-sanctioned for use as the basic resin in food packaging applications and presents no food additive concerns, assuming it is produced in accordance with good manu facturing practices. As you know, PDA proposed in 1975 to ban all rigid and semirigid PVC products while allowing continued use of thin film and coatings or closure liners. The Agency has never finalized its 1975 proposal. Continuous refinements in PVC production techniques have reduced the level of residual vinyl chloride monomer in rigid products to levels which are hardly measureable and which are of little safety and regulatory con cern. This opinion was expressed by the Agency in a 1979 letter, a copy of which is enclosed for your information. For years the Agency has promised a new regulation for PVC. In fact, we*re now told to expect something before "the end of the year." It is our understanding that a new proposal will be issued reaffirming the acceptability of rigid and semi rigid PVC products provided they meet certain residual monomer specifications. Informed rumor leads us to believe that a limit of 10 parts per billion (ppb) residual monomer will be placed on such products. Lower limits of residual monomer are anticipated for plasticized films and other plasticized pro ducts. In any event, we recommend that when Vista PVC resins are formed into various food contact surfaces, the residual monomer levels in those surfaces should be no higher than the aforementioned levels. If you are interested, we can provide VEV-144514 f A Bruce H. Borsuk August 12, 1985 Page 5 Kbixsr and Hsckmax analytical methodology which ia suitable to determine the residual vinyl chloride levels in your materials. The materials used to prepare the basio #VC resin include suspending agents, initiators, chain transfer agents, and killing agents. These are all considered pm#t of the basic resin and, as such, are of no regulatory concern. Calcium stearate, which is used as an antistatic agent, is considered GRAS in section 184.1229. The antioxidant BHT is prior-sanc tioned in section 181.24, while the other antioridant, Irganox 245 (ethylene bis(oxvethvlene)-bis-(3-tertbutyl-4-hydroxy-5methylhydrocinnamate)), is cleared in section 178.2010 for use at levels not to exceed 0.2% by weight of rigid vinyl chloride plastics prepared from vinyl chloride homopolymers and/or vinyl chloride copolymers used in accordance with a prior-sanctioned or applicable regulations. A copy of this regulation is enclosed for your files. We note that the formulations for Vista PVC Resins 5255, 5305 and 5385 all use less than 0.2% Irganox 245. Because these substances are GRAS, priorsanctioned, used in accordance applicable regulations or subsumed under the basic resin doctrine, they may be used as intended. We understand that odorless mineral spirits may be add ed during polymerization of the vinyl chloride and subsequently "-^removed during the polymer drying process. This treatment increases the porosity of the PVC resin which, in turn, improves drying and subsequent blending with other materials. No residues of the odorless mineral spirits are expected to remain in the finished PVC resin after dfying. As such, the ' mineral spirits are not anticipated to be a food additive. Nevertheless, and as an added measure of comfort, odorless mineral spirits are cleared for use as a direct food additive In section 173.340 as a defoaming agent for use in processing beet sugar and yeast. It is our opinion that when a material is cleared for direct food additive use, it may be considered GRAS in indirect additive applications provided the anticipated levels in food resulting from contact with the packaging mate rial is far less than that permitted from the cleared direct food contact uses. This is the case with the use of mineral spirits here. To summarize briefly, all components of Vista's PVC Resins 5265, 5305 and 5385 are either prior-sanctioned, GRAS, or cleared under an appropriate Food Additive Regulation. UEV-144515 f A Bruce H. Borsuk August 12, 1985 Page 6 Km.gR ano Hecxmak Ns trust you will find ws have bean responsive to your request concerning the FDA status of Vista's PVC resins. If you should have any questions concerning this matter, or if there is any other way we may be of help# please 4o not hesi tate to contact us. ,? Cordially yours? ?ZttL Enclosures Peter L. de la Cruz r ENCLOSURE II REACTOR ADDITIVES (INCLUDING SOURCES OF SUPPLY) A VBTA tONnOEMUi Suspending agent: Sodiua tri-polyphosphate Hydroxypropyl nsthylcslluloss (1.5Z solution) Dow MsthoesI F-50 Henkel MHPC-25 Polyvinyl alcohol Ghossnol GH-20 (Nippon Ghossl) Polyvic S 202 (Signs Chemical) Initiator: D1 (2-ethylhexyl) peroxydicarbonate, 751 in QMS Lucldol (Psnnvalt) Lupsrsol 223-M75 Witco -840 PPG-EHP-74 Dllsononanoyl peroxide, 75X In OHS Lucldol (Psnnvalt) Lupsrsol 219-M75 T-anyl psroxypivalats, 50Z In (MS Lucldol (Psnnvalt) Lupsrsol 554-M50 a-cunylperoxy neodecanoate, 75Z In OMS Lucldol (Psnnvalt) Lupsrsol 188-M75 Uitco E-939 Lauryl peroxide Tert-butyl pemeodecanoate ' Lucldol (Psnnvalt) Lupsrsol 10 Killing agent: a-methylstyrene Thonpson-Hayvard, USS Chemicals, Dow Chemical. Allied Chemical VEV-144517 A MNWm Chain transfer agent: 2-ethylhexanal (2-EH) Eastman Chemical 2-mercaptoethanol (2-ME) Phillips Petroleum Morton-thiokol Calcium stearate: 48Z dispersion in water with 2Z surfactant Wltco Chemical Lubrlcal 48N Thompson Hayward (Mallinckrodt) Odorless Mineral Spirits: C9 to CXI aliphatic hydrocarbon blend Shell Oil Union Oil of CA (AMSCO) Vista LFA (data sheet attached) Antioxidant: Phenolic Phosphite: Unlroyal Naugard 492, a blend of Naugard 431 and Naugard PHR. Naugard 431: Naugard PHR: 2,6-bls (a-methyl benzyl) p-eresol tri(mixed mono & dlnonyl phenyl) Phosphite + 1Z trllsopropanolamlne BHT (Butylated hydroxytoluene) F i enclosure III u omcif Ksun Heckman * February 10, i960 (202) 956-5* Mr. Bruce Borsuk vista Chemical Company P. 0. Box 19029 Houston# Texas 77224 Rot PDA Status of Bisphenol-A Dear Brucoi In our December 16# 198S lottor# wo recommended that# as a aattor of prudonco# the residual bisphenol-A (BPA) level be determined in Vista's polyvinyl chloride (PVC) resin. You have now completed this work and have informed us in a January 30# 1986 telephone conversation with Chuek Breder that the resin contains 185 parts per Billion (ppa) of BPA. Based on this data# and for the reasons discussed acre fully below# we have no hesitation in providing our opinion that BPA can be used as a polymerisation termination agent (kill agent) in the manufacture of PVC in full compliance with the Pederal Pood# Drug and Cosmetic Act ("Act") and all applicable Pood Additive Regulations. A. A+OTHtqrr To put our opinion into prospective# it may help to review the legal/regulatory background applicable to food con tact substances. Section 201(s) of the Act defines a "food additive* in pertinent part ass fA]ny substance the intended use of which results or may reasonably be expected to result# directly or indirectly# in its ! * Mr. Bruce Borsuk February 10, 198* Pag# 2 Kiusi ako Hschcam becoming a component or otherwise effect ing the characteristics of any food . . . if such substance Is not generally recognized ... to be safe under the eru ditions of its intended use} except that such term does not include-- *** (4) any subtance used in accordance with a sanction or approval granted prior to the enactment of this paragraph pursuant to this Act. This definition is repeated in section 170.3(e) of the Pood Additive Regulations, which adds, again in relevant part, the following explanatory informations A material used In the production of containers and packages is subject to the definition fof "food additive"] if it may reasonably be expected to become a component directly or indirectly of food packed in the container. .... If there is no migration of a packaging component from the package to the food* it does not become a component of the food and thus is not a food additive. Thus, a substance that is reasonably expected to become a component of food when employed in a food contact application must be: (a) the subject of an applicable Pood Additive Regu lation, (b) the subject of a prior sanction or approval, or (c) deemed generally recognized as safe (GRAS) If the sub stance is not reasonably expected to become a component of food under the intended conditions of use, it is not a food addi tive, and it may be so employed without any prior action by or consultation with the Pood and Drug Administration (FDA). B. Basic Resin Doctrine As further background information. Food Additive Regu lations are all issued on the premise that substances must be evaluated (and cleared where appropriate) on a generic rather VEU-144520 i Nr. Bruce Borsuk February 10, 1980 Pago 3 than a proprietary basis* In ths eass of plastics resins, as long as ths basic resin is: (a) listed in a regulation or otherwise cleared, (b) Manufactured in accordance with good manufacturing practices, and (c) complies with d|p applicable extraction requirements, then the resin is coveplp by that regulation--even though different manufacturers Pay make the resin by different processes* FDA stated many years ago that a "basic resin" is the material that comes out of the polymerisation kettle, l.e., a basic resin is the product that results when the polymerisation process has been carried to commercial completion. Substances such as catalysts, chain regulators, chain transfer agents, and all other materials required to produce the basic resin are considered part of the basic resin and not subject to indepen dent regulatory consideration. Thus, the clearance afforded' the basic resin automatically clears those substances which are necessarily used during the polymerisation stage to produce it. tie are enclosing relevant portions of a report to the Food t Packaging Materials Committee of The Society of the Plastics Industry, Inc. (SPI), in December of 1966. The report covers a presentation by an FDA spokesperson in which the "basic resin" doctrine was addressed. The basic resin doctrine merely reflects the practical reality that FDA could never hope to write generic regulations for food packaging materials that describe and specifically clear every substance that might properly be a component or contaminant of the packaging material as a result of every con ceivable manufacturing process that yields a suitable resin. Since trace quantities of these "unregulated" substances are not perceived to present a public health hasard, FDA has wisely chosen not to subject such substances to the burdensome pre clearance provisions of section 409 of the Act that apply to food additives. On the other hand, the basic resin doctrine does not apply to substances [adjuvants] added to the basic resin in order to prepare a technologically useful plastic packaging material but not essential to the polymerisation process itself. Thus, stabilisers, plasticisers, pigments, lubricants, and the like, which may be added to a basic resin to facilitate its further processing or to affect the technological properties of the final plastic product, must be considered as matters separately from the clearance afforded the basic resin. YEU-l44521 Hr. Bruce Borsuk February 10, 1986 P9 4 KlUJK AUTO HxCXKAH C. FDA Status of BPA Turning now to a consideration of the uaa of BPA as a kill agent, it is, as dascribad above, considered part of the basic PVC rasin ar.a, as such, is of no regulsttffijjr concern. The fact that its usa also seems to convey some thsiinl and color stability characteristics to tha final rasin can ba considered to ba an advantageous side affect. Nevertheless, tha baste rasin doctrine clearly permits tha intended usa of BFA. As a natter of prudence* you have conducted tests and informed us that Vista's PVC rasin contains 185 parts par million (ppm) of residual BFA. Using this information, we have made several vary conservative assumptions to calculate tha maximum potential level of BFA in the daily diet resulting from food-contact articles prepared from such a resin. These assumptions are: (a) no BFA is lost during subsequent high heat mixing and calendaring of the resin; (b) the maximum , thickness of the resulting calendared sheet will be 30 mils (0.030 inches); and (c) less than 5% of the residual BFA will migrate to food' under the most severe conditions of use (Section 176.170, Table 2, Condition of Use E, room temperature filled and stored). These assumptions are considered conservative because, firstly, some loss of BFA will very likely occur during subsequent high heat processing to yield lower residual levels in the final product. Secondly, most food contact surfaces will be thinner than 30 mils and less BFA will be available for migration from such articles. Finally, when tin stablizers are used in PVC at a level of 2% (20,000 ppm), less than 0.01% migrates to food. Thus, our use of a 5% migration factor represents a large conservatism. Using the above assumptions, we have calculated that BPA would not be detected in the diet using an analytical method sensitive to 50 parts per billion (ppb) These calcula tions are contained in a separate memorandum by Chuck Breder which is enclosed for your files. Such calculations can also be used to estimate the maximum potential BPA concentration in the daily diet arising from PVC food-contact articles of different thicknesses and from other PVC resins containing different BPA residual levels. 144522 Mr* Bcue Borsuk February 10# 1981 Pago 5 Ksuifl Aim Haenur Besides being covered by the basic resin doctrine it is unlikely that BPA will become a component of food under its intended conditions of use in rigid and semi-rigid contact articles* Accordingly, it can be employed in Ml compliance with the Act and all applicable Food Additive jgiiilatlons. By making calculations similar to those shown in 'mm enclosed memorandum# and by asauaing that all of the Ml Migrates to food because migration froa plasticised articles is generally higher, it can also be shown that no BPA will be detected in the diet in contact with flexible PVC films of 3 ails or less (30% plasticiser) using an analytical aethod sensitive to SO ppb. Thus, PVC flexible films can also be employed in full coapliance with the Act and all applicable Food Additive Regu lations* We trust you will find that we have been responsive to your request for our opinion concerning the FDA status of BPA for use as a kill agent in the manufacture of PVC* If you should have any questions# or if there is any other way we may* be of help# please do not hesitate to contact me* Cordially yours# Peter L. de la Crus Enclosure cc: William L. McClain# Esquire R* Phillip Carey# Esquire VEV-144523