Document ZJZB98BKQGyOzrZzQbr3L5Rd7

. INSTITUUT VOOR p 'RINAIRE FARMACOLOGIE / EN TOX1COLOGIE ' ,DER RIJKSUNIVERSITEIT ; TE UTRECHT Lx BorioM jop* 6tWellr>d*t ftJItQWit UTRECHT, Maroh 13, 1969 BtfUtrMt 172 Tltoon No. 715544 Monsanto Chemicals Ltd, $00 North Lindbezfr Boulevard, ST.LOUIS (Missouri) USA Bear Sir, In June last year you kindly supplied us on our request with a number of Aroolor samples# Particularly Aroolor.1260 proved to have a peak pattern which strongly resembles the pattern observed in gas ohromatograms of extraots from tissues of sea birds living along the Netherlands* ooast. This qualitative resemblance was further confirmed by using a gas chromatograph in conjunction with a mass sp00tr.0m3_t.er. _, ........ A^paper concerning the quall.tatiye^OQqiPosition of similar residue's in fish'in*tK""river BK^e "and Mrd^.in^tha^}adde_n,_^eai,area has been ac- > pept ecT for publication'by Mfa'fcure11/ and we will send you a^'reprint as soon' acT 'tiiey are avulTable. The quantitative evaluation of the residues was oarried out by geek; Keiftht'oomparis oiLual^.jone^of^ihe._prevaI e n V pe aksin'the' gas chfo.- / Satogram^. In due oourse we will be able to ohebic `tills* procedure by com- ^iariVon with" quantitative measurements oarried out with a miorocoulometrie deteotion system* We would like to go further and Identify the isomers* With the method used at the moment residue levels in sea bird tissues range up to 130 ppm. In the laboratory we have tested a PCB-mixture in a semiohronlo toxioity assay with Japanese quelle. Tissues residues in quail which dlsd during this test were muoh higher than those found In birds vhioh died in our coastal areas. Still, we would like to extend our toxioologioal information in order to try to establish a "no-offest-level'1 in serai-chronic (three months) tests for at least some of the different oompounds present in the wild birds' tissues. W would be glad to know if your oorapany might have available for our purpose some members of the PC3 as pure compounds with known position of the ohlorine atoms. We are particularly interested in those v' ith 4 up to 8 chlorine atoas. For the identification in g.l.o. analysis about 100 mg of each oorapound would be enough. For the toxioologioal test! (with Japanese quails), if possible supplemented with rats, a minimum of 10 g is needed. Ve hope that you may help us and we look forward to your reply. Sincerely yours, MQNS 030155 B. van Oenderen. Professor of Veterinary Pharmacology and Toxicology, University of Utrecht,