Document B5B147zLY8ooy82D2QML90dj8

Pleete eddrest onj- reply to THE GOVERNMENT CHEMIST end quou; Your reference: Mintstry of Technology LABORATORY OF THE GOVERNMENT CHEMIST Cornwall House, Stamford Street. London S.E.1 Telephone; wAterioo 7900, ext fcfy RECD2 7 FED 1967 2}rd Fobruary, 1967* Deer Dr. Hardy, With reference to your letter of 20th February to the Ooremeent Chemist end our dleoueaioa on the telephone the following day, I oen oonfira that we are eery interacted in this Laboratory in the suggestion by Jensen of the University of Stockholm that oblorinated biphenyl ooqpounds 00our la wildlife. As you are aware, we have for some years been examining eeleoted foods, human tissue, wildlife, eto. for organoohlorlne pestleide residues. The work on food and human tissue has been carried out on a systaoatie basis for the Saientiflo Sub-oomaittse on Poisonous Substanoos used in Agrioulture and Food Storage, Mills the wildlife work is for the Nature Conservancy. We have found that wildlife, In partioular, often contains a nuaber of eonpounds whloh produce a series of peaks on gas ohronatograae when using eleotron-oapture deteotore. These peaks do not correspond to pestloldes or their known breakdown produote or metabolites but they soaetiass interfere with the determination of the pesticides. We have spent sons time atteaptlng to Identify these unknown oonpounds which oeour at quite low levels, probably parts per million at most. Their close similarity has prevented us from Isolating Individual compounds but, oolleotlvely, we know they have a high chlorine content - about 50f - similar to the organoohlorlne pestleldee. This led ue to think that they might be derivatives of such pestleldee as DDT or dieldrln beoause we never seemed to find them without one of these also being present In substantial aaounte. Ws also considered that they aight be eonpounds of the pestloldes with sterol or protein material or be polymers or lntsr-oondvnaction products of the pesticides, of Experimental work failed to oonfira any of these hypotheses and baing short of etaff wc abandoned the work until we obtained a positive lead. Jensen's announcement caused us to examine a sample of Aroelor Besin whloh we found in another aeotion of the Laboratory. We find It gives peaks on tbs gas chromatograph fairly oloao to thoaa which are given by avian liver and wo are now carrying out further work whioh looks promising but wdmmfr whieb it would bo foolish to prejudge. Bren If we find Aroelor oompoundt to bo responsible It will raise a number of important questions eueh as how doee it get there end why aainly bird life, and some marine life like seals, and so seldom in mb er his foods such as milk, butter, eto. We shall be pleased to examine any further sample* of Aroolor which you send us end let you knew the results. I snelose a reprint of the section of tho 1965 Annual Bsnort of this Laboratory which may be of interest to you. MGNS 090315 Tours sinosr"," Dr. D.V.N. Hardy, Monsanto Chemicals Ltd. 1S0.-f1.81Y. iotoria Street, J.O'C. Tattoo