Document J3dgGn4reJQ54mD1RaqDM1XDe

Mousaito mou (mamc uacATON) E.A. Lidgett - Ra&bon o*Tt l**CT wctcto+c* , 30th January, 1970- Visit to Unilayor Research, Colworth. 1 7I~^Q'XiH-- ------ ----------- , RAJL/meh TO ; R.A. BAXTER B-A, VQDDEN r CONFIDENTIAL The visit was made at the suggestion of Ur, G. Tilling and waa concerned with analytical problems in residue analysis. The question of the source of p.c.b.e waa inevitably raised, but not pursued, and it would appear that Unilever have little information on the usuage and quantities produced. The meeting mu useful and gave a good overall view of Unilever work on residue analysis. Continued contact on an analytical basis will be valuable since the . programmes of MCL and Unilever on p.c.b. analysis differ sufficiently for. __ exchange of information to be profitable In a practical sense. _ The following points from the meting are of interest. 1, Unilever have to date concentrated on development of methods for the accurate determination of organo chlorine peeticidaa and have only recently started to measure p.c.b.'s. They have, however, developed a successful means of separating p.c.b.'s from pesticides and are now able to measure most of the contaminants (including DDE) in animal and fish residues. The method differs from those at present in nee in that it ie coeqjletely non destructive, i.s. measurement is not made by difference. It will be published shortly, but we have been given full access to the details until then. 2, North Sea herring have been analysed and have p0c.b, contents in the region of 1 ppm. Aqueous samp las have not been examined, but this is probably the next stage with the Severn high on the list. 3, Aroclor 1242 has not been observed in extracts and again it appears that Aroclor 1254 or the higher chlorinated biphenyls are being suspected as the min environmental contaminants. Unilever are sure that fish degrade the lower p.c.b.'s (approx. >- 4) end therefore the chromatograms do not . represent the original p.c.b. but have not yet pointed to 1242 (probably because they have no information on the production and uses of the various . Aroclors), ~ \ i' I sun convinced that many of the measurements of pcsfeieh have so far Win identified as Aroclor 1254 (or equivalent) or above '$* fact, degraded Aroclor 1242 and that it is only a matter of time before this neaelusion is reached by Unilever and other organisations. 'w" ' ojj. mm. This document is CONFIDENTIAL by order of the U.S. Diit, Ct,,, S.C. Dist. (Whitfield C.A. #8:84-3184-3) dated 8/1/85. GPFOXO0054309 WATER PCB-SD0000040978