Document jN5bad19Zxw2r7p6vBe9ZV13R

sj) .cij) Lead In The Atmosphere In Association with Certain Industrial)Operations. //Operations of ^interest, located in the San Francisco and Los Angeles ( antiknock compound containingntetramethyllead. areas, incTucfcf tTTe~blending of gasoline with^the filling of tank trucks with such gasoline at refinery loading racks, the filling of barrels with gasoline, the testing of the gasoline by various methods (distillations etc) in refinery laboratories, and the dispensing of the gasoline at filling stations. The environmental conditions associated with these operations, with respect to the concentration of lead in the atmosphere to which workmen might be exposed, are being investigated systematically in a program of sampling and ~r~. I /V.V /V*' analysis. Thrg~treiTig--two;7refdiyerxes, one in each area, '' " two sets of; r -r operations a^*5--bein@~subjected-^feo investigation. In addition, twenty-one gasoline service stations were included, ten in the San Francisco area^and eleven in the Los Angeles area. These stations were selected on the basis of the large quantities of gasoline dispeneed and their geographic distribution within the two cities. In order to dateaitnre >the impact, if any, of the use of . ; / I' tetramethylledd upon the/gener-a.l-nv4-romnen4i-^rr metropolitan areas, t ' (' A ' , r' ..... .. , ' f Gtesrervafeforrs are^being made of the concentrations of particulate lead # fXKSSSEftT' in the air at one station in each city. The sampling sites were 2 tK - 5T YlZOJiJ '$Ou selected -a s beiagC^pepreseiita-tive of general conditions -of- the -approximate centers of the downtown commercial areas of each city. Procedure The same sampling equipment and procedures for collecting the samples are being used in the environs of the two cities, all tests being conducted by technical personnel of the two major suppliers of tetramethyllead> ajJ `` ' `'.c. < 'A . C *.y4tA.J AaL, 'Si t - U * "7 <./-r.,, `ft>7. -- n .. v " suppliers 'tir responsible for carrying out the sampling program j-* ^ ' ~f/'./ ^ <C~> i l W r t i i i , . . in a single areatj) row/ ti .^..V ,.-5 M* .* Le,'.. , '-f ;'-/f-*,*' , h/T-U'.. .f_j'C-t ..._i , Zj. #. CtU-f. SLr., ,.*aW K V I Organic lead is being determined by means of specially designed equipment furnished by one of the suppliers. In initial tests, four t*? cubic feet of air -were drawn through the collecting equipment at the rate of 0.5 cubic <e$t per minute. However, as a result of an investigation of the chemical properties of vaporized tetramethyllead^it was found advisable to reduce the rate of sampling to 0.25 eiM^and" to use two iodine scrubbers in series. The lead retained in each scrubber is being determined directly + in the field, and the sum of the two values is being recorded as thejorganic lead per cubic foot of air. The rate <f sampling at the service stations is the same as that 7used in the other test areasexcept that the total volume of air sampled 3 is 8 cubic feet. Before air enters the iodine scrubbers, it passes through a millipore filter, which removes the particulate lead from i the air. The concentration^ of organic lead Mfe determined directly in the -j.u '.i?* to field, while the millipore filters are shipped to^Cincinnati for the analysis of their content of inorganic lead. The'ySoncentrationl of particulate lead compounds in the -v,<. atmosphere jtaSfe commercial centers of Los Angeles and San Francisco are being determined by the analysis of material collected on glass-fiber filter webs p4ieed in Staplex high volume samplers. The material from about C - i d i i ,- h m v - i 2000 ^"of air is being removed from the air by each filter during each s'* 24 hours of sampling. The filter webs are being shipped to Cincinnati for analysis. The following frequencies of sampling are being employed: \_____--- --- -- 1. Blending plants and loading racks are visited every other week. 2. Other samples in refineries^rom^flabora^ories and barrel filling operations) are being collected as uLc./i opportunities present themselves in connection with sP ^operations. These samples are being analyzed only for their content of organic lead. 3. Each filling station is being visited^jtwo times per month. The&f; samples are analyzed for their content of both inorganic and organic lead compounds. SSilpSSS r hj '*' 4-{ particulate material fronjthe general atmosphere are being collected every other day and are being analyzed for their content of inorganic lead. t ? v* 'T?"~f'---h $> '>r V- ... ***'" *4? .2 \? rt `i, kilt** ` m u t ' e'i' The ' XZ.;;S..vLJ i.s rppnrt: derive from 0*9$: Estasse samples V collected up to February 2, 1961 in San Francisco, and up to February 9, 1961 in Los Angeles. Tables 1 and 2 give the mean concentrations and the frequencies of occurrence of certain ranges of concentration of lead in the air at the various locations in the refineries of the two areas. In Tables 3, 4 and 5 are summarized the results of the analysis of samples collected at the filling stations in San Francisco, Los Angeles and Bakersfield. The levels of concentration of lead in the atmosphere in commercial centers in the two cities are compared in Table 6. ... -- ---- T -- , A'W.iW , -la-- Lhe.^Lo-11owing..,di&oussA&-^nd ` ' all of the tables except Table 6, the concentration of lead is expressed in micrograms of lead per cubic foot of air. *t * 5 v. ,, -. . , *4 &> a~ >'I & / For eampaim^s^a^warfek-- tire '"fehTcrs'iTOid liTiixfc.of t * * t. t'--J C-'OxK~"'://.r^ '-aeQ-nriorgr,ai]iy '0 'f "~iead^'per cubic meter of air, a.s...-ge.ixtiraA"ly uuyJ.Jtit( '/Z'yX....;-I *<'' inriustrial-- pracA4-es| it is necessary to multiply \ibA-e~-viriue by tfceflHawU*MBsr 35.3j the number of cubic feet in a cubic meter of air. As may be seen from the data in Tables 1 and 2, the highest levels of concentration of organic lead ars*^ R e s e n t in the air when the f*tr-r/<i.?V/ ... domes of the tank carsjPSre^fifst opened for connection to the lines leading .0 . . , ' . ... , . ,' . to the .weight*tank. ;" A much higher average level of concentration at this location was reached in San Francisco than in the same location in the Los t, Angeles area. The concentrations fluctuatefconsiderably, depending upon the condition of the valve connections(and on hcsfcsoon;air sampling is started. /\ / . _is-"be-Meved--thht the higher average concentration of lead in the air at the dome of tank cars in the blending area of the San Francisco refinery ;f;h. ' f-j -'fev i. >---fy--*1 .. ,, $3s& due to the fact that Sh S*,.sampling was.-s'fc-art'ed as the dome was being opened v ;VT . and ^connections were being made gt-ou_fcli~weigh. In Los Angeles ,i^-^Knry-ic'a'SresT- sampling was started^nly after connections to t h e `weigh-tank had been made. The two sets of concentration are representative, therefore, of two different ;I.C\'M periods of}`exposure at the dome of the car. The peak, concentration of 35 micrograms per cubic foot, equivalent to 1235.5 micrograms per cubic meter of 6 air, was obtained in association with a leak in the dome of the tank car containing the antiknock compound. The actual exposure of the operator under thes circumstances is negligible, since he wears:*-*-approved canister respirator fit <*4u^juch*a.v-=fri roe-t/f> ' f- : : : I' vj iU./ ' A1-- Other operations in the process of^fe4-eding^do not, -^el^gn^-clr d? -iJj\.'y! V .... '; the air within the building ; v -' ; ('-'J C:" '-o w ai-glw&aa-k-)'-o-r-in-- the- outside air of the area immediately adjacent to th& blending,ar*a*w-- an- to--be^ha^ardouis ...lvi:werJ;hfiieas, air outside of the blending building in the San Francisco area contained dead a%*-drrgirer"T'eV'el than that within the building at the weigh tank /iteeifr"'' The reason for this was not Srmmedirat-el-y apparent but it may have been due to the direction of air current,-together with the location of the tank car or the position of the vent, during the unloading operation. The levels of fch concentration of lead in the air at the loading racks were generally in good agreement in the two areas. Average co concentrations on top of the trucks were 0.64 and 0.85 micrograms per cubic , -*s CO foot, respectively, at the San Francisco and Los Angeles sites. At the Los <z> Angeles operations, the average concentration at ground level was slightly higher than that at the top of the truck. The reason for this is not -enrtrxrtrty-- - J2a>LriH^'-X... - 7 found at ground level at the loading rack in the San Francisco area. /'- dtir Iraft-- p eni sampled during the filling of barrels with ^ 'JC.J U:.[tv, f . / iV-.A, , Sr'-s-i - -w lj ) < '" / gasoline containing tetramethyllead on only three occasions.; Organic A J, 'fM lead could not be detected in the air during any of these periods. Twenty samples collected in the chemical laboratory were also negative. A 1 R K ~ trace of organic lead was present in the air of the inspection laboratory / ...> r F&tJ the wharf (locally designated as the "long" wharf) in Ri chnuwd-r**'* - Small quantities of lead are~~being found in the air at filling stations. In the San Francisco area, the total lead averaged O 0.26 micrograms per cubic foot (9.2 microgram/M ). Of the total.lead, 43 percent.or 0.11 microgram per cubic foot (3.9 microgram/M*^), was inorganic, |/ / and 0.15 microgram per cubic foot (5.3 microgram/M**), or 57 per cent, was inorganic in nature. In the Los Angeles area the total lead in the air at the filling stations averaged 0.132 microgram per cubic foot (4.7 micro gram/M^). The inorganic lead constituted 64 per cent of the total lead present (0.085 microgram/ii^itfequivalent to 3.0 micrograms per cubic meter of air. The organic lead averaged 36 per cent of the total, being 0.045 microgram per cubic foot, or 1.6 microgram per cubic meter.of air. At one station in Bakersfield^ where 19 samples have been 8 nrf: ', collected to date, the average total lad concentration^was 0.28 microgram per cubic foot of air^,equivalent to 7.9 micrograms per cubic meter. Inorganic lead averaged 70 per cent of the total, or 5.5 microgram per cubic meter. The higher average concentration of organic lead in the air filling stations in San Francisco as compared to those in Los Angeles, is due totdifference^ A"" ln Los Angeles,^air is being sampled near the fueling islands, but not in the immediate vicinity of the gasoline pumps. In San Francisco, the intake of the sampler was,located at approximately the same level as the opening Si the fuel tanks of .. () * a t ' f Ji j j i * . -.'j r ; * - .... tins carl !and 'about two feet from the opening, -in-- &he-- as-e-- o-fjSan Francisco, -a \ l - y r x ' * A Cf.' . t J b j l t j , .. <T V . ... r, ' T f. <& MUfcKV * * * * & 0 * 4 0 0 4 Y f r x ? A ' > f"'1:-- if-- t j t (: A 4 U ` t- here^ o Ke,, t h t ^ "SS1e1rTK?rt^ ary^ t h s pyp^ gM ^ -p /'J/yf T*~`w--' -.y; i* AG i ,;sP jet**}' 0 ah airgtTi^Trtr-~M ^lTt----be--e'Ub^-eotO'tL_;if.,.h e r em ained a.L s.uclx.,a.- jJoL jrt- dxu:ina:. i h.e- J 4.m |I~s, (hg# A*< /v St^-i enfcixe-- pe^riod-of-- f-ueling.y., In Los-- Angel fis.].l-thp -ley1f *J, Jt&tJXii/i to. j '"f*-- - -A'w A / ' ip {v t^n ^. ^,,.Qo-P'-dtrties peTforined by tn-e-- alrtenda-nt. to-- --f * >CJ - C - ^ x .v.-0 %^, e ..if-P va ethCfrj^ * sets of data*. supplement each other in certain j~-f' ' vi i ;' i; variable possibilities for exposure to vaporized tetramethyllead at service stations. ^TtwaxT-^^gK^ --------------- KHSSEBme " The average concentration of inorganic lead in the air the 9 "/ --e.Qafflj.*^~Trn fceT^i Los Angeles (5.3 raicrogramAO is approximately tZriM three times as great as that in the air of the eemmcrri-gJ-e eiTfeg r (1.9 * O *%*- f O F* rfm*.-uiA }W,U:'V; microgram/M*3) o<f San Francisco. The average aaa^nnin.ntww .sin.nn-na-- ' the present investigation tA tu*,.., 4*/ c*u4 ij- ,,i^f.eiMMrirjpwteft--ompagie<i with th ave rage* 3 3 rjA "Ttrggfes of 5.2 microgram/M and 2.4 micrograms/M found in Los Angeles and San Francisco^respectively^ in 1954 by Chambers and associates (Chambers, L.A., Foter, M.J., and Cholak, J. "A Comparison of Particulate Loadings in the Atmospheres of Certain American Cities), Proc. 3rd Natil. Air Poll. Symp., Pasadena, Cal., April 18-20, 1955; 24-32). Additional information dealing with the impact of the increased use of motor fuels on community air pollution nay be gained by comparing the average concentration of . Oi , 5.3 microgram/M , as observed in the present investigation,.with that of . ./ -q 6.75 micrograms/M , as found in August to November of 1954 in Los Angeles. (Cholak, J., Schafer, L.J., Yeager, D.W. and Kehoe, R.A., Chap. 8, "The CO O Nature of the Suspended Matter, Report #9, An Aeroraetric Survey of the Los O Angeles Basin A u g . - Nov., 1954, N.A. Renzetti, Editor, Air Pollution Ar Foundation 1955). < . / A * r.'--- v -'fA-o At < Afw '`/f'' S5 . - : z; tfv*ftriiiY'f ' P 1'4, -.C.j * f . ; The ctur=en-<r-l'e^ej-s-=o-<<oa3en-tn*crtri ons' are >o.f i n t er est La-- -Lbe--- A -"AI ht) -- % At t i l ' ft '-MA is contrary to predictions based on napifee calculations from contemplated 10 been given nationwide puclicity. The results of the current investigation while limited to a single central station in each city, t<$<*vv a-WJS-'i / aae-s^ea-a^lUA^fcrftadiw^TtvHyh romanpemts -to that -JV-,-.? . '^'w /\,i fr t_ > ffi**#, i,asj..v obnei'iiul Tir"ClflCf'MiaTT7 *)i f W t . t J U J , J M 'f, '? . -*in-GnQ.i]naf*e*^*~~~..iy66>M-- 845- , __ V' that _the . trend^^--Hi^''trgm?eiidMPar(?TO~n~r^ A d ^ i ^ J'^h%-fitmasffhexevia^^^ ;5 .; i*W* /, ^~)du&&o&A4 Mq? ktS- * ';f f Several factorsj. were responsible fors-thAs^treneh-- iwelmliHg -the b u M d i g -J'. " lj' # f" . >(5\ *>* /t *j ,, . . > _-. `A > \ ^ /* <&/ f * > * d - i- fciriO ' i f i c U i i .i t * ) i|4 ")%', of expressways, the expansion of populations into the outlying area, and the opening up of the basin of the city, all of these tending to increase the dilution of $!g& contaminants. (Cholak, J., Schafer, J.L. and Sterling, T.D., The Lead Content of the Atmosphere. To be published in Journal of the Air Pollution Control Association.) 8S\J 0 U i o tZ.vf feZ3