Document M4j8JaNnq248joGMjpBbyzOYj

- ^ GENERAL ELECTRIC CORPORATE RESEARCH ANO DEVELOPMENT P. O. B< SC H E N E C T A D Y . N. Y. 1 PH O N E (516} 246- DIAL COM M 8* ^ iU Building K-l, Room 3B35 October 17, 1978 James D. McKinney/ Ph-D. * Head, Chemistry Section, EBCB '* National Institute of Env i r o n m e n t a l *- Health S c i e n c e s . ...... . P.O. Box 12233 ***_. . .. . . J77 Research Triangle Park, N,CT.'27709 ' ' my\'_ . *'* -- . ** ** * '* Dear7Drr^cl<ihney7 . 4 _ " 7 Iv7'._' *'* Many thanks for your letter-of September 22 d e s c r i b i n g your analyses of used and unused transformer fluids, and y o u r tentative conclusions regarding, their implications. These findings "and c o nclusions raise a number of questions' that I believe should be straightened out before we make any attempt to get the story into the published literature: some that we will have to---w-o-rk on from this end, and stohmaet I'd like to p a s s b a c k to you. ; . -, ' ; - -' ' % x*.; ^ 7 -* 4 ' t ` t V V V ; 1. Evidence for Ch l o r i n e R e d i s t r i b u t i o n . Y o u r e p o r t e d finding {V. broader distributions of, b o t h chlorinated b e n z e n e ^ a n d c h l o r i n a t e d `^>.4biphenyl horaologs `in- the used oil than in the fresh sample, and pos- ^ i s i b l y different isomer di s t r i b u t i o n s as well.. Y o u r s u g g e s t i o n that xSIi'this implies a'redistribution of chlorines on the a r o m a t i c rings would be of considerable chemi c a l significance. A s b e s t I can tell', one has ever chloride with etc. for 20 has no way knowing what the transformer- owner's maintenance crew did to maintain the level: of-dielectric fluid in their t r a n s former during 'iS?'Vthe 20+ years that it'was in service. ' However, if p e r i o d i c additions -n\ ':were required'to replace leakage or over-zealous s ampling, these ad. ditions could well have "included Aroclors 1242, 1254, and 1260, and any available chlorobenzene mixture as well. Thus, the observation of a broadened homolog di s t r i b u t i o n is not s i g n i f i c a n t unless it turns out to be clearly b r o a d e r than that present in any of the PCB's and chlorinated benzenes in commercial use since the early 150 's , AKS30 783277 ir rZ i - 2- What would be significant is a change in isomer contents from the rate-controlled dis t r i b u t i o n s p r e s e n t in fall of t h e i n i t i a l families of PCB homologs towards equilibrium-icontrolled distribu tions in the "used1' fluid. Y o u m e n t i o n e d concern If o r s u c h changes i n distribution b o t h -in- y o u r letter a n d over the p h o n e , but.. X d i d n 11 see any concrete support for altered isomer distributions in your analyst's report. Did I miss something? If you still have the o r i g i n a l .ehromatogramg and~ id ewti-Firafinng w e w o u l d b e V e r y i n t e r e sted in h a v i n g 1copies- s o as to b e a b l e t o assess Ithe e v i d e n c e fo r alterations in e i t h e r *h o m o l o g o r isomer distributions. [ 2, %Evidence for' F o r m a t i o n `o f P o l y c h l o r i n a t e d D i p h e n y l Ethers in U s e . As b e s t I ca n dete r m i n e f r o m y o u r chemist *js A u g u s t 4 r e p o r t of analyses of Dr. A l b r o 's F.N. 2A fractions J p o l y c h l o r i n a t e d d i p h enyl ethers tPCDPE's) w e r e found i n the unused as w e l l as the used oil, implying that they must have been present at least partly as contaminants in one of the ingredients use|d. U n f o r t u n a t e l y , w e d on't k n o w the actual c o n t a m i n a t i o n levels ofj eithler t h e f l uid o r i ginally placed in-the transformer or of th make-up fluids added over its- lifetime. As b e s t I can d e termine from t|he o l d - t i m e r s around here, there w a s at least some prod u c t i o n ofj P C D P E 1s b y Do w in the early 1950*s', b u t n o one can reca l l whether- it e v e r g o t used in dielectric, fluids. I 'v e also n o t y e t b e e n 1 able' to fi n d o u t w h e t h e r there is any data on PCDPE levels in commerci'al po'lychlorinated benzenes, but will continue to keep asking around the C o m p a n y . Un less w e can turn up someth i n g d e f inite along these lines it m a y be difficult to figure out whether there actually was an increase in PCDPE in service.' 3. 'Evidence for' P C D F 's' in U n u s e d Oil. - I am a l i t t l e confused here by some seemingly contradictory statements, and wonder if you could help me* out. Y o u r chemist's letter of Augusjt 4 s t a t e s that limited mass searching for the molecular ion cluster of chlorinated dibenzofurans' revealed the presence of several such species in new transformer' fluid fraction 4B, and estimated a consent of roughly 10 pp m - f o r this family of homologs. - This i s .a s u r p r i s i n g number, since fraction 4B s hould h a v e 1b e e n d e p l e t e d in P C D F 1s r e l a t i v e to the starting material, and other homologs should have been present as well, implying a total P C D F c o n t e n t in thej initial s a m p l e of new. fluid that would be somewhat upwards of 100 ppm. Other reports of P C D F 's in unused Ar o c l o r 1254 of r e c e n t m a nufacture h a v e r u n in the 0-5-1.0 p p m range. I also note th a t y o u r c h e m i s t 's n e x t s t a t e m e n t is that a PCDPE gives the same m a s s p e a k as a| PCDFl, a n d that his re port o n th next fraction off his o r i g i n a l column,] .N e w T.F. 2A, .described the species se e n s P C D P E ' s rather than P C D F 's. I certainly agree that any discrimination between PCDF's and PCDPE's 783278 GENP 010467 0* 7ie\ - 3- in a situation like this would b e pretty difficult. M y q u e s t i o n is, under what circumstances can the distinction) be made at all? Does . y o u r c h e m i s t -really h a v e evidence t h a t NewTj.F. -4B`contains' PCDF's; b u t n o t P C D P E ' s , and N e w .T . F . - 2 A contains P C DPE *sr but* n o t P C D F 's ,,, ; or did it somehow happen that the peaks got bailee one way_ one d a y and the-i-other w a y on another?" W e - a x e obviously, q u i t e disturbedT b y this/ since-a-100 p p m level of PCDF's- in new A r o c l o r s implies ... . ah exposure hazard that no one had been aware of previously; and if PCDF's really are una n a l y s a b l e in the presence) of P C D P E 1s, then we're stuck with no way to assess their presence in used oils in our service shops- 1 In short, any further information or clarification that you could supply as regards eith e r the q u e s t i o n of isomer d i s t r i b u t i o n ' or PCDF/PCDPE discriminability would be most)welcome. Other than that, I found both the reported data and your comments mo s t interest* ing. W e are deeply appreciative, of y o u r efforts to date, and* h o p e ' that some rationalization of the remaining ambiguities will soon emerge. Sincerely yours Vr / John F - Brown, J r . Mgr Life Sciences Branch - PHYSICAL CHEMISTRY LABORATORY 783279 O