Document 1gVM6QpOn7wG7LvEOegRB4XNq

ETHYL CORPORATION I NTER. OFFI CE CORRESPONDENCE TO Dr. Robert A. Kehoe ADDRESS f r o m h . k . Seales ADDRESS SUBJECT DATE Cincinnati New York December 1966 I attach a copy of a page from a confidential report to the Pennsylvania State Chamber of Commerce Pollution Abatement Committee for their use in their deliberations on November 1J, 1966. The entire document vas entitled "Background Material for Ambient Air Quality Criteria Developed by Council of Technical Advisors - for Pennsylvania Air Pollution Commission Meeting - ll/lk-/66." We had a meeting over at the LIA offices this morning and Don Diggs gave me a copy of this report. You will note that the section on lead describes the basis on which they used your testimony at the Muskie Healings in June to arrive at their criteria of 5 u g / . There will be a meeting of the Health and Safety Committee of / LIA this Friday, December 9, which will be attended by both Don Diggs and Harold Hesselberg. I just tried to reach Hess by telephone but he was not in the Labs. Idid, however, dictate the section on lead to my secretary and asked her to pass this on to Hess if he should come in this afternoon and in turn to request him to read this to you over the phone so that you would be aware of the basis for the proposed 5 ug/M^ criteria. We are hopeful that by getting this information to you as quickly as possible you would be able to review it and make some preliminary comments as to what you might visualize as a rebuttal to this reasoning. Rather than have several people get in t o m h with you on this, we agreed that it would be desirable to have Hess handle this with you and for him to take the responsibility for reporting back to the Health and Safety Committee meeting on December 9 as to your views. - I am sending this by mail in case Hess does not get in touch with you this afternoon and in the hopes that it would reach you by tomorrow morning so that you would have it for reference if Hess is delayed in phoning you until tomorrow. Best regards. Richard K. Scales / ^^ RKS/ec attch. N7540 Kg'0006241 2- - Set tried ?a iculates a Air Basin Average nc maximum air oasin average v.aritn: '.c u i c ..^ea n ) c r i t e r i o n , 1 . 0 m g / c m 2 / 3 G d (29T/mi2/mo), was arrived air by considra; :ion o f t h e a i r b o s i n u V c r a e a *.ofc settled particles in each of ten air basi; G S u U C I C u j o r u n d e r s t u d y , b y t h e D e partment. These range from about 0.5 mg/< :m.2/3Cd f o r t h e L e v i s t o w n a r e a t o a b o u t 2.2 mg/cm2 /30c for the Beaver Valley. It w a s t h e s u b j e c t i v e o p i n i o n or. t n o s e "Citing tnese studies m a t a value or 1 . 0 i .g/cm." / 2 O d , a s a s i n g l e m o n t h a i r b a s i n average was the maximum acceptable. For t.rio s a n e o r e a s y r e f e r e n c e t h i s v a l u e is roughly equivalent to a three-month air basin average of about 0.7 mg/cm-/mo (20T/mi2 /30d) or an annual air basin average of 0.6 mg/crr.2/30d (17T/mi /mo). m e sliding sc e value, t('Cic ~" 00..-31///2 mg/cm"/30d was derived in a simi-ar way as the sliding scale for suspended particulates to take o account land use, The formula requires a "rollback" for settled particles of a factor of two (above average background of 0.3 rag/cnr/30c), except for the most extreme cases where the maximum of 1.0 mg/cm2 /30d applies and a rollback of sop factor of two will be required. b . Single Point Measurement The maximum single point criterion, 3.0 ;mg/c ~r/ 30d (86T/mi2 /mo), u as ce rived so as to avoid extremely high values at any on e samoling sca11 on , v/hic might be possible even although the air basin ave y X. err*0rre cr iterion IS TTiCt , 4.C value chosen allows for a three-fold varratio a fr on* the basin av orage. It 1 third lower than the calculated maximum sing! a po m t vai uo used in M. Y . Sta (3) i.e., 4.5 mg/cm2 /30d (equivalent to a med .an of 1.5 mg/cm2 /3 Od) . one > 3. Lea d Recent testimony by Dr. Robert Kehoe (4) indicates that a total of 0.5 mg/day of lead can be ingested regularly without any risk, so long as there is no sig- nificant increase in the intake of lead from the atmosphere.' Dr. Kehoe estimates that the average amount taken in from the atmos-phere- is between 0.2 and 0.3 mg/day. He also estimates that about 10% of the amount ingested is absorbed and 50% of that i-vaaled is absorbed. ,. ' Us*"g these figures the total al lovable absorbed dose is about 0.08 mg/day Since the average amount of lead abso rbed from ingestion is about 0.03 mg/day, this leaves about 0.05 mg/day permiss ible absorption from the air. Using the 50% absorption figure `and a daily res'"piration rate of 20 H 2 (for the "standard -- ,I \ the calculated average dailv concentr ation which will lead to 0.05 mg/day absor ?tion from the air is 5 ug/M?. This calculation is based on average conditions xihich will be most nearly ' duplicated over a long time period such as a month. Furthermore, in this range or absorption, load has only long term cumulative effects. Daily fluctuations, by even a wide margin, would not be expected to have any demonstrable ill effects. Consequently, the criterion of 5 ug/!lJ was established as a 30 day average con centration, without regard to daily variations. N7540.01