Document oxaRb11KYm0JNoN3QL1a2jr

Plasticizers Beoause all plasticizer uses of PCB were regarded as essen tially "open" to the environment It was Impossible to pre vent the leaching and volatilization of FCBs. Consequently Monsanto realized the untenable nature of these applications when the allegations concerning environmental contamination by PCBs were confirmed. We discontinued all sales of PCBs to domestic U.S. customers for plasticizer ap plications one year ago. ; The type of application affected by the market withdrawal of PCBs were: [ Surface Coatings Sealants Adhesives Printing Inks .| Miscellaneous (e.g. pesticide carriers, wax modifiers,, catalyst carriers, etc.) Coatings s"I*' 4 ,,Industrial (maintenance) coatings were the main outlet for PCBs In the surface coating Industry. PCBs were chosen over other plasticizer candidates because of their outstanding chemical and moisture resistance. For example, PCB-plasticized coatings have enabled Industrial equipment to withstand attack In strongly corrosive atmospheres. j At present alternates being offered! to the eatings industry are ohlorlnated paraffins and chlorinated bitpheny-lsChlori nated paraffins are Inferior (stability, chemical and moisture resistance) to PCBs. Chlorinated terphenyls sa far appear to be equivalent In1performance to PCBs. Sealants In the 1950s, synthetic elastomer sealants began to replace traditional putty-type caulks and sealants. One of the major synthetic elastomers was polysulfide. PCBs were used In these sealants to give excellent adheslonjto a variety of substrates, moisture and chemical resistance, and for reducing hazards with the catalyst systems employed In curing the elastomer. These PCB plasticized polysulfido sealants were essential to meet the MONS oV*229 -2- cauIking and sealant needs of modern buildings and construction. Our discontinuation of PCB sales to!the sealant Industry has oreated a very real technical problem for them. Totally satis factory alternates do not yet seem to be available. In fact it is reported that PCBs are being imported from non-Monsanto sources for use in sealants. ! MONS 034230 Adhesives In the 1940b and 1950s, PCBs were used In adhesives to Impart tackiness and because they exhibited excellent bonding power to many substrates. They also exhibited greater compatibility with a wide variety of the many resins used by the adhesives Industry. In a word their versatility led to their wide usa'.e. They were also chemical and moisture resistant and resistant to heat and oxidation. In the mid-1960s, however, a drop in their usage had already become evident. Adhesive suppliers were Increasingly called upon to supply PDA-approved, low-odor products. PCBs did not satisfy these developing market needs. Even before the environmental pollution situation arose we were engaged in developing and supplying new plasticizers to meet the needs of the adhesive market. The new products are 'not PCB-based. ! 03-*i3V Miscellaneous Uses Monsanto's Aroelor1' Plasticizer Bulletin o/PL-306 may appear to the layman to indicate that PCB found its way deliberately into almost every product produced In the nation. Applications such as dedusting agents, pesticide carriers, catalyst carriers, impregnating compounds etc. are listed as Aroclor and have been so publicized by the press coverage given to PCBs. The faot is, however, that very few of these uses accounted for more than 4 or 5 drums of PCB per year and in many cases the Aroeloi used was not a PCB. j In 1969 an exhaustive survey of our:PCB customers was made to determine exactly where these products were being used. An example from the survey may be of lhterest. We found only throe customers in 1969 were using any PCB in pesticide formulations. Total consumption was between 5 to 10,000 pounds PCB per year. This application was developed by U.S.D.A. scientists at Belts- ville, Maryland in the early 1950s.! The aim was to Incorporate "chlorinated polyphenyls" Into lin dane and possibly chlordane to improve the residual effects. To Monsanto's knowledge there was never any recommendation by anyone for their use on food or oth^r crops. The principal application was to spray metal or painted surfaces to increase the effectiveness of the active pesticide against flies, ants, roaches, etc. In April, 1970 we wrote to Dr. Hayes, Director, Pesticide Regulations Division, U.SiD.A. suggesting that no approvals should be given to pesticide formulations containing PCB. I All applications of a- "miscellaneous" category uncovered during our 1969 survey of customers buying|PCBs through the Plasticizer Business Croup of Monsanto were included in the sales ban put into effect in August, 1970. PCB APPLICATIONS IN PLASTICIZERS U.S.A. only (Prior to Discontinuation) TO* Surface Coatings Sealants Adhesives Miscellaneous 57 17* 6f> Bncapsulants The use of PCB as a solvent for the' encapsulation of dyes for oarbonleos carbon paper began In the 1960s. Factors which influenced the selection of PCB were: dye solubility ; U.V. light stability Intensity of color: development speed of color development moisture resistance . non-reactive with dyestuffs In spite of research efforts for the past ten years it has only been In the past two years that the; promise of satisfactory alternates have been brought bo light. Since 1970 we have been supplying non-PCB alternates to this Industry. The search for even better replacements continues but none of these is based on PCB. ENCAPSULANTS U.S. SALES OF MONSANTO PCB S' 1965 1966 3.5 4.1 1967 1968 4.4 6.0 1969 1970 1971 Estimate 1972 Projection 6.5 6.7 1.2 0 1 MONS 034233 Dye Carriers \ <K j U-u Polyester fibers are notoriously difficult to dye and hence a usage of specialty dye carriers has;built up. Historically this has been based on biphenyl (l.e. a non-chlorinated product) In 1969 there was a trend toward the use of low chlorine content PCB. Biodegradation and medical feeding studies have shown this particular PCB to be non-hazardous to the environment. However, even this use is being discontinued within the next two months in favor of a monochlorinated product. jDYB CARRIERS U.S, SALES OP MONSANTO PCBs Prior to 1969 0 1970 1.0 H lb. 1971 Estimate 1.1 1972 Projection 0 MQNS 034234