Document RpEGgMwwrO2RoBEN0Gw98vMOa

July 31, 1968 Mr. Jerry Pierce Teohnloel Director Preoieion Founders Ino. 414 Hester Street Sen Leandro, California Dear Mr. Piercei 1 have been asked to disouss with you the toxioity associated with vapor inhalation of Aroolor 1254 and Arcelor 5460. As you know, the Aroolors are a group of chlorinated diphenyls which have been manufactured by Monsanto for a number of de cades in amounts ranging into the ten's of millions of pounds. Their vapors do possess toxioity but the exposure must be con sidered along with this toxioity. Thus, while we can get a softening point or a vapor pressure for various Aroolors, we cannit list toxioity as an absolute. We must always consider the type of application. I understand that one of your uses of Aroolor 5460 will be welding wax at a Joint, using a soldering iron. My impression is that this will be oarrled out scsMwhat above the softening point of Aroolor 5460. This is in the neighborhood of 98 to 105C. At this particular temperature the vaporisation rate is extremely low. In faet, it is 0.000004 g/sq. cm. an hour. It Is ay opinion that such an exposure will not constitute any hasard. As far as Aroolor 1254 is oonoerned, this is, of course, a liquid and possesses considerably greater vaporization. I do not know at what temperature you will be using this but should vapors evolve, they must be collected. OSH 020314 STLCOPCB4008243 -2- Botto these Aroelors have vary good warning properties, as the odor Is prosont long before the allowable concentration Is reached, I fool suro thsso ArooloM oan bo usod In your application If good housekeeping pmstioos and a alnlws of ventilation, such as la usod in aost good oanufaoturlng practices, is afforded* Tour nalo rats mm subjected for 6 houM to tho vapors gsnsratsd by heating Aroolor 5460 to 300P. lhe lnslds tsnpoMtuM of tho ohaabor, where tho rats were exposed, was 75,5P, All of the aniaala survived the 6 hour expoeuM as well as the following 10 day observation period. Toxic signs, during the exposure period, were ooderate lethargy and dlsooafort with olid weaknesa in 20 to 30 ainutee. There was slight to alld nasal lnflaaaatloo. IheM was no notice able ocular irritation* The aniaala were in no distress when reaoved froa the chaaber. Activity and appetite were nearly nomal within 24 hours* Although this vapor data indicates no aoute toxic hazard, the natuM of the Aroolors in general, being ohlorlnated hy drocarbons, indicate that Mpeated daily expoeuM should be avoided when they are heated to elevated teoperatuMS, If we nay be of further service, please oontact us directly. / boot k. wells SlneeMly yours. Wllllaa H. Hunt, Ph.D. Toxicologist, mdlcal Oepartacnt DSW 020315 STLCOPCB4008244