Document Z4067y9ydVQaXkjgZ6kZKLEv8

Monsanto nw tHM toeATioNi R.A. lld|tt - Rusbon " JOtli January, 1970. Vllt to Unilever Research. Colworth. ' (A.P. and R.A.tn * . RAL/sieh TO : R.A. RAXTUl H.A. VQDDliW <* C0NFIUIJNT1AL The visit was node at the suggestion of Ur, C. Tilling and vaa oonoarnod with analytical problems In raaldue analyala. The quaatlon of the eource of p.e.b.a wae inevitably ralaed, but not pursued, and It would appear that Unilever have little Intonation on the ueuage and quantities produced. The meeting waa useful and favo a good overall view of Unilever work on reeidue analyala. Continued contaet on an analytical baole will be valuable ainee the programme of UCL and Unilever on p.e.b. analyala differ aufficiently for exehange of Intonation to bo profitable In a practical aonao. The following pointa fron the noting are of interact. 1, Unilever have to date eonoentratod on development of methods for the acourate determination of organo chlorine pesticides and have only recently started to measure p.e.b.'a. They have, however, developed a auocosaful moans of asperating p.e.b,'a from pesticides and are now able to measure most of the eontaminants (ineluding SUB) in animal and flah residues. The method differs from those at proaent In nos in thnt it ia omspletsly non destructive, i.o, measurement ia not made by difforoneo. It will bo published shortly, but na have boon given full access to the details until then. North Son herring have been analysed and bava p.e.b. contents in the region of 1 ppm. Aqusous samples bavs not boon examined, but this la probably the next etaga with the Severn high on the list. 3. Aroolor 1242 baa not been observed in extracts and again it appears that Aroslor 1254 or the higher ehlorlnated bipbsnyls are being suspected ss the main environmental eontaminants. Ubllavor are ours that fish degrade tin lower p.e.b.'a (approx. > 4) and thsreforo the ohromatogramo do not repreeent the original p.e.b. but have not yet pointed to 1242 (probably beeauso they have no lnforsmtion on the production and uses of the various Aroclors). ) . 1 am convlneed that smay of the measurements of p.e.b.'s which have so far Sbn Identified as Arcelor 1254 (or equivalent) er above are, la fact, degraded Arcelor 1242 and that it la only a natter of time before this monolusion le reached by Utailover and other organisations, S.V.I. M R.A. LIDOETT MONS 099940