Document MyzevQY0gbE7Ean5yBg33Xnk

J SAL 000019432 of about 55 ug/YOO ml would seem to provide Mother physiotomail host* <o support (he recent OSHA proposal1 N^hat "the maximum upper Mood lead levels workers should remain below 60 Mg/100 g" v A semi-lot P*w (figure 2) converts the arithmetic dose-response dtirve to straight bnc. There is the usual scatter hkrc. characteristic of biological responses, but^thc correlation cocffictnM for the direct relationship between log ZP and lead conical is qtac good (0.1), which suggests that blood 2P might be substituted lor blood lead as e preferred biological index of eaposurc\ Several advantages would be offered: (7) Vp more directly reflects the metabolic damage aused by lead and is thus a more uaeful indicaloXof the effects of lead absorption. tfjContaminatiM, an ever-present source of concern and care Vilh lead analyses, is minimal in the dctcrminai ZP. (3) ZP assays are simpler, less costly, ai more rapidly performed than blood lead, there-' by permitting moreeffective use of resources and enhancement of any monitoring program The foregoing findings, it should be noted, were developed for an industrial population chronically exposed to inorganic lend. Organic lead compounds may follow a somewhat different course through the body, and may not exert their major toxic effects on the hematopoietic system. Hence, a biochemical index such as ZP. may not be appropriate a* a monitor for the effects of organic lead absorption. In some other disease states (e.g., erythropoietic protoporphyria or seven iron deficiency anemia), the use of ZP may also not be suitable, since elevated ZP levels can occur in such conditions without concomitant trad absorption.**" Such situations are unusual, however, and likely to be well known to the worker. Hence, the ZP test should be generally applicable to moat workers exposed to lead, and should be given serious consideration as the biochemical lest of choice in monitoring such populations cknowtatfgMnante Special thanks arc extended to Dr. Donald Sherman for providing the Mood specimens of the workers used in this study; and to Erodita Empaynado tor excellent technical assistance. U.g Osasmw in el NaoMh. Ct______ _ _ PMiam: Cfforo for o Ootmtmondod Standard Oeeueaoenst fuMwr to Organ* Public WasIPi Sarvsca. Nauonol bwMirt# tor Occiwarwnei Safely and HesfWi |1972| JseaSsnr. M. M.: toBums at Stood load Lottos. m MeaM flbm at Ocrwaeoanef IMS and Arson* tap*sera U S Oaaanmam at Health. Education ndWaMata. HEW PublicationHo IMIOSHIS 1)4 (197| 9 Msk N. W.. t.me*alary (hafnoau at tnrraasarl lead Aboorpiwn Arch Environ ZtoaA/i 29 199 0974) 4 PlomaM. (a) hberomathad tar Fred Eryiivocyia Parphynna Out Mas 70 497 (1972k lb) * micro molnod tor boo orythrocyi# perphyrma tho FEP a J tu> C/#n Mad $t 932 (1973| torraaaad wad abruption toad , Wm chian Camar tor Omaas Control Public ih $*fv (March 197*1 0. lainate. A.. M. Joaatoov and T. Vamana: Zik Protoporphyrin IZPPI a Simple Sonsmvo. Flutownoiric Screenmg Teat tor lead Potsorong Ckft bum 2f 93(1976) 7 HassatXo 9., A Simple and Rapid Quamnanva OatormMinolloadtftBtoed At totwf toad 7 95 09601 M. and J O Baudan: SmpMiod Micro-method tor Ctotocuon and Oatarmmanon at load n Btootl Uung a Paper DitomOaHos Cup fachmqua AtWsarpr toad tt 99 0 972) 9 PwpSiyrUiPiadncta. two.. P0. Boa 31. lagan, Utah 94321 ^ >; Propoaad Standard Fadorat Wayaiar OO'Oto I93.4593 46949(0ei 3. 1975) Mapmis. I. A . T. Jansn, A. 4. Pianhard and C. RbmUHoo: Eryitwoputoilp Prmepiapfiyiins lancer 24490961) is. tsia MCD 000009659 *" *** * tout j W Iwiaai <VI Off Ms fob bontono roper onpoaurma of toaa Mm 5 ppm woro mooaurod concurrsnf with tho 24 hour coHoction of urtno from 82 mptoysM. Urinmry phono/ fooo/a of tho cotoctfn ttutfy group, mooaurod of oithor eoneontrotion or wight. ahowod o poaftfvo atotitticofhf significant eorroiotbn wrtA ksmsns oapoouro. Howorat. duo to vorioncoa in indhfiduot boaohno phonoi bvsb. dotormmotion of bontona aopoauro ot thoao Ipso eoneontrotiona fa roiotbfohf mooh. Smgo boaohno phonot eoneontrotiona oaiat poor o rongo of roh/oa, odfuatntoot loro smgto voiuo ofooch tndMduot, boaohno did not improve eorro/otion tor tho cottocthroatudv A study of benzene exposure versus urinary phenol levels GOADON J ROUSH and M GERALD OTT HER Industrial Htfsiti Laboratory Corporal# ModicaiOoponmoni. Th Dow Chanucot Corporation Midland. Michigan 46640 introduction The 1974 NIOSH proposed standard for benzene' requires the monitoring of urinary phenol levels ol employees with lime-weighted average (1WA) exposures exceeding S parts per million (v>v air). The correlation between benzene exposure and increased urinary phenol levels has been reported previously.' A level of 75 mg phenol i liter of urine (mg/1) is proposed as a signal of unacceptable benzene absorption requiring close medical surveillance This studs was designed toevaluaie the proposed technique of "biological monitoring- in an industrial environment It was also intended to determine if concentrations in the area of 7S mg phenol. liter ol urine are indicative of unacceptable benzene exposure. bwiuwff* vppor awnpHng procadura benzene is widely used as a raw material and solvent by The Dow Chemical Company Five benzene-consuming production facilities were selected to represent industrial environments where benzene is handled along with other chemicals Over a six month period, benzene exposures were studied fur 52 employees from 2* ftWi tflcVrficjuons including lahoraiorv teclinifmn. production operator, plani mechanic, and material transfer operator Usually, samples were obtained from two employees in each job Participation was voluntary since the collection ol urine depended on each person's willingness to cooperate Urine samples and breathing zone air samples were collected on the same day Increases in urinary phenol levels were expected to correlate direct h with inhalation of benzene vapors Skin adsorption was assumed lu be negligible since most )ob required the wearing of rubber gloves when handling benzene Potential exposure io other chemicals should not have affected urmarv phenol levels since none were known io interlerr with, or contribute to the metabolism of benzene to phenol. Actusl TWA exposure to benzene was determined via personal samplers worn on each employee's collar throughout the course of hia workday Workdays varied from 8 to 12 hours in length A small battery powered vacuum pump provided a low air flow rate. 100 to 250 milliliters per minute (ml, min), through charcoal packed stainless steel lubes A f:w "extra largecommercially available sample tubes were used but most of the sample collection tubes were custom-packed with Pittsburgh cmomii base ** Mutual iiiqim simuuw xxmov ilo > r~ activated charcoal. 12-30 meah. Charcoal waa used because of it> suitability for collection of a wide range nf aromatK compound* which were likely to be encountered. The cuatom packed tube* were approximately 47cm(3/16 in )in diameter by 12.7cm (3 ia > ia length and contained approximately one gram of charcoal. Efficiency of the total templing ayatccQ. including error of analyst*. wai determined by apikmg tamplr tube* and submitting them for analytic with tubes used in monitoring. "Spiking" of the umple tubes waa acmnipitsbed by preparing in a 100 liter Saran* bag a known concentration of bencene, both by itaetfand with a mixture of other chemicah found in the work place. Air from the bag eras drawn through a sample tube at the same flow rate used in the plant studies. Collection of urine began when the employee started work, and continued for 24 hours. The "day" sample was collected in a hospital specimen container while the employee waa at work. A second container for the "night" sample was taken home and used until he returned to work the following day. Thus, the two "combined" urine samples represented' approximately 24 hours of urine. A baseline urine sample was collected by each employee after being away from work fora minimum of46 hours. No other restrictions were placed on the collection of the baseline urine sample. Information concerning consumption, within the Iasi 24 hours, of any medicalion, tobacco, or alcohol was recorded by each employee for each unite sample. Any known chemical exposure was also noted. Information concerning previous or present health problems, particu larly of the liver, kidney, or heart, was requested for each volunteer. 10% SP 1000 5% FAPP 5% QF 1,11% SF tO 10% UCW 9M 10-20% Carbowax 20.000 Mb SP 1200 1 23% Bcnlone 34 10% LAC 2R446 13% Carbowax 4000 10% DC 200 Df*pal OPN /Poracil C 0/100 The columns ranged in length from 1.13m (6 ft.) to4.37m (IS ft.| and were prepared from ,95cm (I/I in.) inside diameter stainless steel tubing. Column temperatures tanged from 11.3 to 66J*C <65* to IS5*F). Selection of a column depends on the combination of chemicals absorbed on the charcoal. A column packed with SP 1000. Durapak or SP 1200/Bcnlone would be suitable for benzene alone. Urine phenol analysis was based oo the NIOSH proposed standard for benzene.1 The urine samples were hydrolyzed with perchloric acid at 93*C for two hours, saturated with sodium chloride, and extracted with isopropyl ether. The ether extract was analyzed for total phenol using a flame ionization ps chromatograph. The only modification of the NIOSH method was the saturation of the hydrolyzed urine with sodium chloride This step increased the extrac tion efficiency of the isopropyl ether. The chromatograph column consisted of a lube .93 cm (I /I in.) in diameter. 1,63m (6 ft.) long and filled with 2% EGA CG-AW-DMCS <960-100 mesh) packing. The followingtemperatureswere utilized: column at I60*C, injection port at 2302S0*C, and detector temperature el 290-300*C. Maximum sensitivity under these conditions was about 2 mg phenol/ liter urine. anafyslo of aamploa mk raiph* The charcoal absorbent used in air monitoring was desorbed with cold carbon disulfide and analyzed by gas chromatography using a flame ionization detector. Specific chromatographic conditions varied over the several months of personnel sampling. Column packings included: 20-CtlbttWII 20.000 0000,` 09 roauHa 4M Table I lists dais collected from air and urine ample analysis. TWA benzene vapor exposure concentrations are given as ppm (v/v) and they are grouped secotdiog to the length of the workday. Concentrations of phenol in unne ere `lltMtni Intail nt TM IW C liiMUl Co*H*l at>a4 AM M <** 4MC 1 'Ml Irtrui'l t*77 TASLC I h--um Ate Campting team) anU Urtwe AnatyUa tmg/Q WwW________ Cwaroiia Aww 1 A--I m umw. --n * Haws _______ UMjfrirws______ M>Q*H -t---- ----- ------ -f___ "WWW___ iaauw 40 1 II 11 i II s 1 11 1 12 s t 1 12 as 1 1 0-0* 2 7 12 12 is M 0* IS 12 1-12 p- . St 2S 14 17 IS *7 4* 3 as 3 3* cemeuw* 2* 14 * 2 17 20 2 20 I SI 3 IS n 2) 11 17 M 3 10 2H 7 20 Om" tmrn Cwaau 1 23 37 IS 2* 13 14 <1 1* 1/1 ;,tn,)V 4<r -a* - 17 JO 21 14 22 Sft * IS a 77 HI 44 ) It It 10 2S 2S 2 20 11 12 * oos SOS 1 1 1 1 1 1 1 2 1 1 1 4 S S 27 1 41 22 38 24 27 sa . ' sa 4 S 4 4S 22 12 SI 2k >3 s a 2 > 1) 44 4* * 4* IT , . . 1] ai at. ai s 4 24 >1 32 3* f 12 1 14 12 11 22 *17 ' It * 10 7 10 ft * s <1 II 21 S 10 S IS IS 20 .llift 1ft id s 7* 40 *4 ST M IS 4* a *2 4* II 46 2S 10 17 i* 11 1 21 4 24 4 21 4- IS 4 i 4-IS 0 2 IS 4 12 41] lift S 11 #-11 SAL 000019433 i * expressed as mifligrams of phenol per liter of urine (mg/I) The concenirationt are listed as measured, and as adjusted according to the NIOSH proposed benzene criteria. The following equation was used to calculate the adjusted values. Adpuicd CwKcairaoo* Last 2 digits Measured of NIOSH *w- Cooccn- ' ip specific iriiwB ptvii) ' '<Y 1st! 2 digilt of mcsMj.ed"---4&Z specific entity '* 1 ^OSv^W.JMk TABIC N fteeutW oS Ah gampBwg |pwU end tbtno Anetyaie (wgt TVS* 0 0* annua in o* psmi Urwe. Sown Atjftgmt ti OmiWii 32 21 22 12 IS * 3M 721 .IW! IS 7 7 ] a 2S 7 11 77 2S . Mit ia is 14 4 3 1 4 I1w}| lOwJJ 12 S 1 7 a 23 i tea 20ta&7 -lOte ft 0 1 0 0* 21 1J 7 S 32 17 12 4 ft 17 1ft S 2# 36 20 11 1SJ 177 ia i 10 11 1 ij a ft 10 17 12 7 2 14 S 3 3 u, 10 134 r 0 1 6 74 to 2 ia 2i 4 11 1 14 1 | Mo A V 1 a 1 |g ? ft* to 1 ilWflMM JOUWMl l 1'" TABLE IM CwWcuiW (mm CwHHioM * ImtM I\K f pmi ii ** Wlpt of P*mm( and Urinary CMd ConcwoiMiaitf TWA at a Maw 4M 111 taWa Saamant Oa* C--iW Wnw CmNUmh oa* os OS) a--w OSS 0*0 067 woaN *4|m,m4 oaa OS) 0*4 nw* a 11 mm nwi>m iu maw Os, Cm mwiiau 044 0 II 0)1 0 41 oat on 0Z) 0) 041 TWA ri MaWwa*UImUII nau> bar C(AM 030 040 0 41 04* oa* 0)7 041 04) oao *--* ------- r r- r T r-- mUms * caaaaaf MoaacaptatSa WMl Mwcwwanaiia Wail Oar Nra CiwWnaO oar oat 0 71 oaa oat oat oaa oaa 077 rev* at enaWratu VIMll new IIMriMlI. ft (MM at iMMMMk M**1 MWM'MlM MMf II bw 070 ______________________ . Not 4 f*<imi tmiliim akAM m Mm (HI MM at* lath (idm mw miaUlipa catlttcnM ibM X. V. SaTa juMidil |MMaltl)l i^-l| (W CSSTiiniM^ii *m> i - mMh <f mwmi K. f piMIM iMf (dlMH TIm average ipeoTK gravity of urine uacd by NIOSH it 1.024. At a comparison. the respective average specific gravities of urine samples included in (bit report were 1,021. 1.021, and I 022, for lhe day aamplct. night tamplet and baseline templet. These values are similar to those recently reported* for a large work population. The weight of phenol meaaund in the urine temple* it shown in Table 11. Phenol wei^il wat of interest at an alternative to concentration at n meant of measuring btazenr eapoaure. Measuring weight instead of concealration would eliminate the problem of low phenol concentration due lo the intake of large volumes of liquid. This dilution ofurinary phenol levels it bandied in the NIOSH criteria by measuring .-ocdfic gravity, compering it with a traditionally uacd average, and adjusting the measured concentration accordingly. rarralsfi'arr of da< suftwtwt Two main parameters, urinary phenol concentration and phenol weight, were correlated with measured employee TWA beruene exposures. The correlation coefficients and the equation uacd in calculating them are chown in Table III A correlation coefficient is a measure of the strength of relationship between two variables. In Table III, most of the coefficients exceed 0.3. a value reprraenting the highest correlation which would be expected if random numbers were substituted for the reported sainpie values. This value assumes a ample site of 32 observations and a confidence level of 05% or p <0.05 Since meat of the coefficients exceed 0.5, in moat imiawces a positive significant correlation exists between TWA benzene exposure aad the two different measures of urinary phenol levels. Figures I and 2 are plots of the strongest relationships for phenol concentration and phenol weight respectively. Besides comparing two methods of reporting urinary phenol levels. Table 111 indicates the different ways in which the experimental data sis analysed Obvious subgroups eiisl in the total of 32 observations reported. Examination n a <w w 4iioc j <m rsai isr? MCD 000009661 i exposure and urinary phenol levels. The tegheai '*;irj correlations in Table 111 occurred when the f(wl > * persona with high background phenol levels ( were deleted from the data. These correlations are Statistically significant at the critical level, p 0.005. If persons with high bowline* are included in the data field, the bat eorrelxtiow arc significant at 0.0005 <p 0.003. However Figures I and 2 show the unpredictability of this association at relatively low.axpo*uie levels. These figure* are "ili'ili'ig high baseline phenol tewM^pUPgswersted the ,, highest correlation btaupqb ^jpfjawol macro l I-TWA Smww u*MM wMtapMMnr). cs/xraowt at pftww/ </> ytmm 16 cMMsfAgnasMArw cooesiwmwu eUWfMQ of the data included analysis of them subgroups as well aa the total group. Twoof thesub-groups in Table III resulted from the sampling of employees with two different length. S and 12 hour, workdays. A third sub-groupwith the high baseline urinary phenol levels bernmt evident after the data bad been collected. High bareline levels are apparently normnt for some individuals and these individuals may exceed the concentration of 75 mg/I. proponed in the NIOSH document as aa unacceptable level of 'absorption.** The five individuate with high background phenol levels wilt be discussrd in more detail later. They were deleted in the last two correlation poupa in Table III in order to determine tbe degree of influence they exerted on the collective group. The last correlation in Table 111 was an effort to further examine the relationship between excreted phenol weight and benzene exposure. Since the data had been collected using two different length workdays, it was logical to expect a higher weight of phenol to be excreted io tbe "day** samples by persons working the longer day. This was assuming vapor exposures were fairly equal throughout the workday. The individual phenol weights oolkctcd during the 12 hour workdays wen reduced by 1/3 to equalize them with the I hour workday The correlation of this adjusted "day'* weight of phenol is reported as the Ian section ofTable III i This study agrees with previous studies bkawten ib garni correlation between benzene tration/weight aad TWA bMac exposme. Plots of data which iadndid Pfrsona with high baseline phenol levels showsd pa seen wider aad more unpredictable scattering af points. Tbe solid line in Figures I and 3 ifV least-tqoarct '^ plot, or regression line. The broken bncs represent plus or minus two rewduol standard deviationi and should contain netween them , approximately 93% of the data point). Efforts to use the regression line la predict benzene exposure resulted in the aquariom shown in Figures I and 2. The ppm value for two standard deviation* is given below each equation. Two standard deviations for these, the best two correlations, represent an unacceptable 35-40% of the experimental (0-5 ppm benzene! data ' range. For example, assume an employee's urine was monitored end it contained 25 mg I of phenol. Based on Figure I. (he beat conclusion that can be drawn is that the employee is 95% sure his TWA benzene exposure was between0 4 and 3.9 ppm. Or. if 100 employees were monitored for one day. and all of the wnne / ftgurm 7- TWA San/a/w t<palw( phtnoi m OmtptHi) IS <*>*! o! far* m&t/ht r cwKMWMasm nuswu mun 71 - V * - `4v * SAL 0 0 0 0 1 9 4 3 4 TAStf IV *" CaiffialaiiM to* TWA Iwiwi Varava Urinary Ptonol WWM. Amwi i ao4 ltna#i--4 * lrt>iW Ptmol l--aa *-- iff .... ........... iim, n mu 0t mm taWiil rw* o iz hM saw ' Oar MOM CoaUn-ae nwA at tiwwivi u s wo tz tow iinvmi Owr Wl CaoWnaa twtaawmtio II W HUM S tan * iminrQMSU UM Par SUM Censmea fWA O ohm* at S MO 11 lour 0v* COOMMIHM MMM II IM oUpr*UW>aMiDM|)Ny<apt* " MmnnAhM Tl wmiilaniwH oaa oe OSS oat 0 IS 0 12 OSS 0 40 042 OB7 0*4 OSS OK OSS oao 0M 0 IS 0 2S 041 OS# OSS 04S samples contained 2S mg/1 of phenol, one could iMumc that approximately 95 out of the 100 had had a TWA benzene exposure between 0.4 amf 5-9 ppm. Leu than 10% of the time will an employee'* actual exposure fall on (within 0.1 ppm o0 the regraston line. Urinary phenol levels are not an accurate method of predicting TWA bentene exposures in the range of 5 ppm or less. Another observation exists. It is that NlOSH's recommended procedure for adjusting "spot" urine samples to a standard specific gravity slightly improved the correlation of the 24 hour urine samples. NIOSH recommends this taau v Summary of Cmpleyaa* wWi High SaaaMna Urinary Phenol Lawb umwv a--i turn. w/ ppM TWA 02 11 OS OS sa at auraap to*m 2 iy So a* In Save postern tfcWaaS --hi Ma NMM 11 21 Ma PM>W*0 NMM mmfr n 30 Im 20 IS Nana *a fiaStano SS 27 2 <wn a Ma al W Mm IlllH n * Mk rpW-* pwUur a i* Utv wm ia 12 as S3 it *7 SO Baaa 0 12 N SS S2 sa m a Oar IS UM 12 m at n ao 9mm 99 a X2 10* S 47 St SS a sa B4 SS s> a 4S 4t 17 SI 44 47 47 a* 77 It * iiw j ,m mrr MOD 000009662 Lr r i VT IO ' P"H o o o <1 to hgutm J. TWA inwit Mpeaur* imi/i vnaWusTsd mwgf* ot phmmtm m procedure when a single urination ia sampled, to allow for dilution of phenol concentrations due to large volume* of liquid intake. When this adjustment was applied to the various urine segments. Table III. the resultant concentration correlated better with TWA benzene exposure. Ssatpamd pAanof brsb Table IV. and Figures 3 and 4 present the result of adjusting measured urinary phenol levels 0W MsM HI SS0 WOO SIS Sao 44 2S T9 140 I2S 1440 ISO 2SS So toes M*K i aas Im toss 1 Ml 1024 tosa tots 1012 IMS i aa 1 oil tots I OH l 02S s saa 1 MS > MS I 02S as ass 1 02 7 SO 'mi aas 1 014 1 017 Ott 44S i 021 S_ according to each individual's anneal baaoIlM'. level. A baseline urine sample was collected after each volunteer had been away from work or any * known chemical vapor exposure for 41 hours. Each baseline phenol weight was calculated and * subtracted from the total weight of phenol in their "day" and "nighl" urine segments, jTheorctically. this adjustmem should have S; compensated for persons with normally high urinary phenol levels, leaving the adjusted wctfhts of phenol entirely related to beupeue ; <* absorption. Figure 3 is a plot of eoadjmned ^ urinary phenol weight for all 52 observations. ,, Figure 4 illustrnies the effaa of subtracting the bustline pound weights of these 52 individuals. r Table IV compares group correlation ^ , caefliaentx for TWA beazenr expoaortati mss' both unadjusted aad adjusted weights of urinary pbesoL In moat cases, the unadjusted juguigl weights have a higher group corrclarioa than tlye jvffy adjusted weighti. This finding indicates the ; difTtcuhy ia using a siagk value for .busufa^jj^1 urinary phenol leveb. For any indivMtmL^lffil baseline range should be determined accurately assess what phenol level is "ahotV*,-^^ normal. The negative phenol waists m FigpenAr`, ; also indicate that unknown factors are greater fluctuations in baseline leveb than>hpeg >'* resulting Irom low benzene exposures. A study of non-exposed coniroli U underway and will he reported m s future publication. u 71 SAL 000019436 rslarsncM National IniMitU tof Occupational *o*ety and HaaNh Colana lot a flecoiniiMmded Standard for Occupational lipnurr to Banrena ' HEW Pubu canon No 74 137 WHSIvy, J E . 1. D. ftapootlo H CUiMia Tna MtovUiKtix Of Shtnol m llono h an Indti <it Ban ran* Enpoaura 4m InU t*rf 4mc J 72 Ml Oban sunBaas, w a., ft. ft. Clavatad Urinary Pfcanol tana tifoiu* 4m An I IS7SJ kMAmki f 111* and ft J. not Batata* u> Ban. 4*aac J 36BZO While consideration of baseline phenol levels for a large group does not improve eorreUlkm nth benzene exposure, its consideration can very heavily influence correlation for individuals with naturally high baseline phenol levels. Urinary phenol levels approached or exceeded the criteria action level of 73 n|/m' in one or sore urine samples of live different persons, or about 10% of the total number of persons sampled in this study. Several urine sample concentrations of these five persons are shown in Table V. both as measured and adjusted according 10 NIOSH formual. The baseline concentrations indicate that these five individuals frequently, but not always, have higher thaa normal <>30 mg/I) phenol concentrations in their urine. Average levels for these individual's varied from 40 to 60 mg/1. but the full range of measured "normar urinary phenol levels varied from 3 to 100 mg/1. Analysis of the sample data. Table V, did not indicate a (one-to-one correspondence of high urinary with any of the known parameters, such i sample volume, specific gravity, medications, lical problems, or age. There it no indication in this study ns to why normal urinary phenol levels fluctuate over relatively broad range, and are charactrnislically high for certain individuals. cotscluaiona I A positive MatiMical correlation exist! for urinary phenol levels versus TWA benzene exposures, at exposures of less than 3 ppm. This correlation is statistically significant st the 0.003 level for a large group of people. Both total weight of phenol in the urine, and phenol concentration in urine gave similar results. 2. The correlation between individual benzene exposure and urinary phenol levels is not strong enough to assess past TWA benzene exposures less than 3 ppm. Assessment improves if individuals with normally high n background phenol levels can be identified and treated as special cases. Even so. the actual TWA exposure may be 140% of the exposure determined from urinary phenol levels. 3. Urinary phenol levels, which have been adjusted for baseline values resulting from a single measurement, do not have a higher group correlation with benzene exposure. 4. Baseline phenol levels for a group and an individual can vary over wide range. Approximately 10% of the persons in this study exceeded the "unacceptable** level of ?S mg/I. as expressed in the NIOSH proposed hen/enc standard, even though ihev had no known exposure or their I WA bcn/enc CKpoMire was less than 3 ppm Tl 4 M ** 4tMc j (* tat>M>r un MOD 000009663 ABIH annual certification anamination* Exuminettone lor eertlficMloft by the Americnn Bourd of Induetriel Ifygiono wMI be held in Now Orieone on Moy 21 and 22. 1877. Thu following msmfnsHtrT wiN bo conducted. * CERTIFIED INDUSTRIAL HYQIEN18T - Thie coneiotu of o two doy written aeemmetten The lint doy ie tho CORE examination In the beelc principlao of Induetriel hygiene prncitoe. Tho ooeond doy oonolata of enomlwotlowo In tho Comprohonohm Praetioe or in on Aspect of induetriel hygiene..o.g., Poounttedl. Air Pollution. Chemistry, Engineering and Toxicological Poroono who ham eomgimed one part of dm ouommotion oMCUOOOfulirnoodtshoonhrdioother pen. INDUSTRIAL HYOfCNIST IN TRAINtNO Thie conolsH of tho CORE ennmlnotlon covering the beeic prinriplsd of induetriel hygiene practice Quolificationo for admisaion to tho above ounminotiono include e boocnlourooto dogrse in o ciermo i liweti rotated to induetriel hygmne end induetriel hygiene experience varying from flue yomt for o condMote tor CortMod Induetriel Hygioniet to one year tor induetriel Hygienist in Trobwr^ Up to one year credit moy bo oHowod tor e completed graduate degree. INOV8TNIAL HYOfCNC TtCIIWQiOaHI ~ This oonoien of a on# doy metoon ssmminotion covering tho prlnelptoa of poriowo lechmcpl aspects of toduoalel hygiene, e.g.. air damping,, laboratory onolysos. oir monitoring, etc.;, QueUhcetlono for odndooieft te\hin puamltwttehi .^Vi* ere e high sehoof diploma end flvaor moreyoeraof experience involving at loom 26% of tho time in Induetriel hygiene ocSMUoo during each year. The Board may accept alternative education - 'A'auperienoe requirements tor paraens having on .Ur.* years in an accredited coffege. -7 : application cut-off data Ail eppliceHone tot examination must bo recewod boffo March 21. 1*77 Alt candidetea ecctpted for aueminetion in Now Orieone must have ihew few paid at leoot 30 days before the examination SpselHc information about otigibilny require menu. tho euominoiiona end tpoHceoon forma may bo obtained from American Board of Induetriel Hygiene. 64 S. MUIer Rd. Akron, OH 44313(2161 834*9336. ,v Tiui--rri-| m fea Ml a M raamam Haaal u n