Document RjR1wEj6ypYV7gLmbqMbo7VvV
FILE NAME: Asbestos Cement Pipe and Sheet (ACPS) DATE: &
DOC#: ACPS0
KhMENT DESCRIPTION: hZZtZZ ^
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Environmental Control Department Research & Engineering Center February 26, 1968
CONFIDENTIAL
W. P. Raines - GHQ
Water Contamination Studies Asbestos-Cement Pipe San Diego
Attached are some figures on ingestion based on San Diego study results, and on inhalation based on the proposed British Threshold Limit Value of two fibers per cubic centimeter.
As you can see, we are dealing with very minute quantities. Ingestion quantity per day is well below inhalation at TLV per day.
While this _comparison is interesting, We are comparing apples and oranges, the TLV for ingestion is not.
I don't The TLV
7)J;
'E. M.'
think .it is quotable. for inhalation is known;
)----
Fenner
EMF/ems
Attach.
cc: F. L. Pundsack S. Speil Att: J.P. Leineweber J. H. Swensen Att: J. F. Herr File
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t>ROOUCED
JM - 83
CONFIDENTIAL
W. P. Raines
- Attachment Pagel
Feb. 26, 1968
Water Contamination Studies San Diego, California
Potable water after two miles through a 17-year old asbestos-cement pipe system had a fiber content increase from ,03 micrograms per gallon to 4.0 micrograms per gallon.
1 microgram= 1 x 10-6 grams (.000001 grams) 1 microgram= 2.2 x 10-9 pounds (.0000000022 lbs)
Assume average daily water consumption is eight glasses, per day. Then daily ingestion of fiber could be:
4.4 x 10-9 lb per day (.0000000044)
or~
gallon
Proposed British TLV for inhalation of fiber is:
2 fibers per cc
or
5.6 x 104 fibers per cubic foot (56,000)
Assume average inhalation rate is 1 CFM.
5.6 x 104 fibers per minute (56,000)
Then TLV =
Assume average
1.
2.
.,,,...---~,"- - ,-l, /c respirable fiber size is
x 10 -x 20' .-.
long long
( (.:~
r
_,.,,., ,,..\_l ~- ~,- - ,L_,
-Yr._.._ ... ....... c- l,: ~ j / j
( 2 .-r-r-" __...,...,._ ._.._ J_,_c_- ~ ( '"2<...' ?-?-'-'-C.c... ,.;_-. I_ 1...._ j
Fiber 1 would weigh: Fiber 2 would weigh:
2.2 X 10- 14 lbs 17.6 X 10- 14 lbs
Then fibers inhaled per day at TLV.
1. 5.8 x 10-7 lbs per day (.00000~18)
2. 48 x 10 lbs per day (.0000048)
CONFIDENTIAL W. P. Raines
- AttachmentPage 2
Feb. 26,1968
Water Contamination Studies (Cont'd.)
Comparison - inhalation vs. ingestion.
A. Inhalation
Case 1.
5.8 x 10-7 lbs per day (.00000058)
Case 2.
48 x 10-7 lbs per day (.0000048)
B. Ingest~on
San Diego: 4.4 x 109 lbs per day (.0000000044)
E. M. Fenner
PRODUCED
JM - 83