Document k96gpVqmR3eBLGQvg7NJ1gvwE

TU.OMOHC ITTINSSOURNK ***. run AR/SB > Or. V.N. Hardy, Monsanto Chemicals Ltd., Monsanto House, 10-18 Victoria Street, London, S.W.l. TUNSTALL LABORATORY, BROAD OAK ROAD, SITTINOBOURNC KENT. ' 2nd November. 1967. Dear Dr. Hardy, Thank you for your letter of 1st November, 19&7- l apologise for not having answered your letter sooner. `\ As you know, we have been for some time examining extracts of marina birds and their eggs In connection with the possible occurrence of* Poly chlorinated Biphenyls. t1 In one particular experiment we have extracted approximately I0Q eggs of the Shag (Phalacrocorax aristotelis) and examined the resulting extinct following liquid-solid chromatography on Silica Gel, by gas-liquid chrcenat- ography-mass analysis and by mass spectroscopy. Mess spectroscopy of a fraction from the Silica Gel column snowed the presence of a compound of molecular weight 1*26 which contained 8 chlorine atoms, this Is consistent with on octachluro biphenyl; gas-liquid chromatography-mass analysis . Indicated the presence of compounds of mass 324, 358, 392 and 426 respectively. These masses are consistent with pentachloro, hcxachloro, heptachloro and octachioro biphenyl4 by being present. In addition we have fed chickens for two months on a diet containing 100 ppm Arochlor 1254 after which vie placed them on normal diet and collected the eggs for a further three months. Extracts of these eggs have 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 chlorinetod constituents are more readily metabolised. I would say that our results are in broad agreement with that of the Government Laboratory and that vie have no disagreement with them; however, I lie-11eve that they may have over-stressed the likely toxic effects of these materials but as you know there Is only very limited evidence for us to go on. We arc continuing our studies on the chlorinated biphenyl and will let you have further information as soon as it is available. Yours sincerely r STLCOPCB4008474