Document qk3DZj2OM1j8Ngd3RpzGgJNBk

/ ildnsanto imoustri ai/.,iemi cals cq. ^? Qecember 3. 197^ evjer VCfMOKI FDA Q6TECTIOH OF CHlORI MATEO 0186NZ0FURANS IH AROCLOR TO : W. 8. Papageorge 82 S K ( ee. R , E . Ke I 1 ft r - 7 | g R.H. Munch - Tig W. R. Richard - 73A Per your recent request, I have talked by telephone with John Roach of FOA regarding his paper at the national meeting of the Association of 0 f ficia I Analytical Chemists reporting detection of chlorinated d I benzofurans (COF) in.Aroclors. This memo documents our converse 11 on. ' According to Mr. Roach, he and his co-workers have isolated and lden tified COF in Arociors 1016, 1242 and I 254 but not in Aroclor 1221. These reference ArocIors were provided by Mon san to. The concentrations were in the Iow (probably l-lo) ppm range. 3 i chIorodibenzofurans were found in Aroclor 10 16, d I -tetra homo logs in Aroc lor 1242 and tetra and penta homo i.ogs in Aroclor 12 34. He estimates their lower limit of detection, at less than 3.1 ppm. ' The analytical method was similar, but not Identical, to that used to determine COF in Kanechlor 600 (see attached reference) . Isolation 0 * the COF was accomplished by column chroma cograony followed 3 v i Jen t i f I ca tion by GC/MS . I raised the question whether stur aotential impurities such as chlorinated methyl biphenyls . * n i c h have similar mass spectra ) cou I d have been mistakenly Jentif i ed as COF. Roach's response was negative, followed 3 v a sooh i stIcated and technically correct explanation that cnay - a v ooeained and characterized several chlorinated methyl 3ij^sny 1 s as reference materials to eliminate this possibility. They are currently attempting to i den tify some of the individual isomers which have been isolated. Roach agreed AOAC meeting completed in findings. to send me a copy of the paper he presented at t*'e as well as a preprint of their entire study when about two months. They plan to publish their Their methodology is similar to that first reported by Vos and duplicated in our laboratories during a 1971 survey of our Aroc1or a-bducts for COF. This survey did not detect any COF with' a lower detection limit of 0. S ppm for each i some r. (Several somers at lower concentrations total ing >1 ppm could have been jrasent). Roach indicated their current technique gives better (but not complete) recoveries than the method cr Vos. FOA also -as a more sensitive MS than our current model, although we will nave a superior instrument a few weeks J . P. Mieur 7 906646 STR G C 6 6 6 T HINlTr'S ex:vait 50000074 l y- 757 WATER PCB-SD0000035045