G Gasoline vanes in composition, but is com monly a petroleum fraction containing hex anes, heptanes, and octanes with varying amounts of unsaturated, cyclic, and aromatic compounds A cracked gasoline may contain 50 percent or more compounds other than the saturated aliphatic hydrocarbons If the gasoline consists of saturated and un saturated aliphatic compounds and cyclic com pounds, it will be a narcotic and an irritant to the mucous membranes The mam toxic action will be depression of the central nerv ous system with symptoms of giddiness, dizzi ness, hilarity, and headache not unlike an alco holic intoxication Mild symptoms of this sort are apt to be produced by relabvely short ex posures to concentrations of 500 to 750 ppm of this land of gasoline In addition, mild blood changes, neuritis, and neurasthenias have been reported If the gasoline is made from a crude oil containing 40 percent or more of aromatics or is ennched in aromatics by the refining proc ess, the toxicity may be substantially higher The tetraethyl lead content of gasoline is low enough to make any lead exposures from ordinary handling and dispensing of gasoline m garages and filling stations negligible Tetraethyl lead can, however, present a toxic hazard by inhalation and absorption through the skm when entry is made mto tanks and other confined spaces that have contained leaded gasoline See Lead.

v f-\h V*-Y' H Z GG; J 4 5 dangers associated with the handling of Fluid with the purely hypothetical dangers arising from the handling of gasoline containing small quantities of tetraethyl lead* Certain articles* which I am sending you* deal with the problem of leaded gasoline.

I think this problem has been discussed with you and It is probably unnecessary at this time for me to discuss it further* However, if there are any questions in your mind as to the nature and magnitude of this danger* I trust you will let me know so I can give you additional information* Dr, Machte has told me that he talked over with you tlie question of information which should be made available to the Harbor- authorities In Hamburg as to the exact nature of the dangers associated with the handling of tetraethyl lead, I wonder whether or not you have taken steps to acquaint these men with this problem.

Webb -- Concerning Tetraethyl Lead Manufacturing Plant in Germany* Purely eoaaerciel considerations sake it imperative that there should be no recurrence of episodes of lead poisoning la the manufacturing end of the industry.

Elements of Industrial Toxicology tivity were observed Gasoline vanes in composition, but is commonly a petroleum fraction containing hexanes, heptanes, and octanes with varying amounts of unsaturated, cyclic, and aromatic compounds A cracked gasoline may con tain 50 per cent or more compounds other than the saturated aliphatic hvdrocarhons If the gasoline consists of saturated and unsaturated aliphatic compounds and cyclic compounds it will be a narcotic and an ir ritant to the mucous membranes The main toxic action will be depression of the central nervous svstem with symptoms of giddiness, dizziness, hilarity, and headache not unlike an alcoholic intoxication Mild symptoms of this sort are apt to be produced by relatively short exposures to concentrations of 500 to 750 ppm of this kind of gasoline In addi tion, mild blood changes, neuritis, and neu rasthenias have been reported If the gasoline is made from a crude oil containing 40 per cent or more of aromatics or is enriched in aromatics by the refining process, the toxicity mav be substantially higher The tetraethyl lead content of gasoline is low enough to make any lead exposures from ordinary handling and dispensing of gasoline in garages and filling stations negligible Tetraethyl lead can however present a toxic hazard by inhalation and absorption through the skin when entry is made into tanks and other confined spaces that have contained leaded gasoline See Lead and Hygienic Guide Germanium, one of the less common metals which have some industrial uses, is employed particularly in the electronics industry for diodes and transistors It appears to be a relatively inert metal and has not been re ported as the cause of any occupational dis eases in man In animal experiments, the LD50 for rats bv intraperitonea!

Kettering Laboratory University of Cincinnati Eden and Bethesda Avenues Cincinnati 19, Ohio Dear Bob: Thanks mightily for your comment on the tetraethyl lead manuscript.

In the course of his work he was handling concentrated ETHYL fluid, which is a mix ture of tetraethyl lead and,(at that time) ethylene chlorbromid.

In the course of his v/ork he was handling concentrated ETHYL fluid, which is a mix ture of tetraethyl lead and,(at that time) ethylene chlor bromid.

Kehoe: TETRAETHYL LEAD OPERATIONS Supplementing fry letter of October. 30th in reply to yours of October 27th on the above subject, I visited the Tetraethyl Lead Plant yesterday with Mr. ftfunson, Dr.

Webb -- Concerning Tetraethyl Lead Manufacturing Plant in Germany# Purely commercial considerations sake it imperative that there should, be no recurrence of episodes of lead poisoning in the manufacturing end of the industry.

Kehoe: TETRAETHYL LEAD OPERATIONS Suppiementin.g wj letter of October. 30th in reply to yours of October 27th on the above subject, I visited the Tetraethyl Lead Plant yesterday with Mr. iunson, Dr.

showed drowsiness starting in the early after noon and later becoming more severe Com plaints of loss of appetite and nausea at these relatively low exposures were less common See Hygienic Guide TEPP (tetraethyl pyrophosphate) is the active ingredient in an insecticide mixture that goes by the same name Since the esti mated fatal dose for a human being is ap proximately 600 mg taken orally, it is m the class of highly toxic materials In its use, toxic dust respirators or supplied air respirators and protective clothing which will completely prevent skin contact should be worn Anyone with a severe headache or a feeling of tightness or constriction in the chest should be removed immediately from the exposure 1.1.2.2- Tetrabromoethane (acetylene tetrabromide) is a high-boiling, heavy, yellow ish liquid used as an indicator liquid in gauges and for separating minerals by density Its low vapor pressure at room temperature makes it safer to handle than might be ex pected The LDjo for rabbits and guinea pigs is about 0 4 gm per kg of body weight Exposure to the vapor causes respiratory irritation and damage of the liver appearing a few days after a single acute exposure 1.1.2.2- Tetrachloroethane (acetylene tet rachloride) is an excellent solvent for a num ber of paints and lacquers It is also a very dangerous compound since inhalation of it at a concentration that is barely perceptible by odor can lead to extensive liver damage Tetrachloroethylene (perchloroethylene) is a chlorinated solvent used primarily for de greasing It is similar m its properties to trichloroethylene except that its boiling point is slightly above that of water so that boiling degreasers containing it automatically keep themselves dry without loss of solvent Its most important toxic effect is depression of the central nervous system In experi mental exposures of human subjects, those exposed to concentrations greater than 200 ppm promptly suffered central nervous sys tem symptoms, while those exposed to about 100 ppm did not See Hygienic Guide Tetraethyl lead--see Lead Also see Hygenic Guide 1375

____ j i j 0 , 0 3 <[ Table 12 Distribution of Y/orkmen Employed In Mixing Tetraethyl Lead with Gasoline ' ' I According to Milligrams of Lead per Liter of Urine . " (f ____ Milligrams of Lead Per Liter of Urine J f i s 27 \ 19.2 9 ........... 1931.............

Kehoe: You are acquainted, I understand, with the fact that the Dow Chemical Company is using tetraethyl lead in a chemical process.

Kehoe: You are acquainted, I understand, with the fact that the Dow Chemical Company is using tetraethyl lead in a chemical process.