Document Ozwb77QJoQqvoqEJ0q7kO59LK

UiniNAfiOl'WJt 4`iA. icutx octet AR/SB TIJNSTA1.L LABORATORY^ . > . ' Si- : BROAD OAK ROAD, SITTING DOUR ME, KENT. 2nd November, 13-S7- Dr- V.N. Hardy, Monsanto Chemicals Ltd., Monsanto house, 10-18 Victoria Street, London, $.V/, 1, Dear Dr. Hardy, . Thank you for your letter of 1st November, 1967- I apologise for not having answered your letter sooner. As you know, we have been for some time examining extracts of marine birds and their eggs in connection with the possible occurrence of Poly chlorinated Biphenyls. . In one particular experiment wo have extracted approximately 100 eggs of the Shag (Phclacrocorax aristotclis) and examined the resulting extract following liquid-solid chromatography on Silica Gel, by gas-liquid chromat ography-mass analysis and by moss spectroscopy. Mess spectroscopy of b fraction from the 'Silica Gel column showed the presence of a compound of pmlemia;* weight 826 which centsir.cd 8 chic, iiiv ni.cx.is, unis is consistent with an octechloro biphenyl; gas-liquid chromatography-mass analysis indicated the presence of compounds of mass 324, 358, 392 and G2o respectively. These masses are consistent with pentachloro, hcxachloro, heptachloro and octachloro biphenyls by being present. in addition we have fed chickens for two months on a diet containing I0D ppm Arochlor 1254 after which vie placed them on normal diet and collected the eggs for a further three months. Extracts of these eggs h3ve been examined by gas-liquid chromatography and indicate that a substantial amount of Arochlor 1254 is excreted into the egg, the maximum concentration being 89 ppm. Examination of an egg taken three months after feeding was discon tinued shows that these materials are very persistent and that the less chlorinated constituents ore more readily metabolised. I would say that our results arc in broad agreement with that of the Government Laboratory and that we have no disagreement with them; however, I believe that they nay hove over-stressed trie likely toxic effects of these materials but as you know there is only very limited evidence for us to go on. Wc ere continuing our studies on the chlorinated biphenyl and will let you have further information as soon os it is available. Yours sincerely. 0631156 PCB-ARCH0745315