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r i L IT I I volatiles of 0.2 mg/m3 averaged over an 8-hour workshift (Final Rule, January 1989); NIOSH recommended airborne exposure limit. for coal tar pitch volatiles of 0.1 mg/m3 over a 10-hour workshift; ACGIH recommendation that worker exposures, by all routes, be controlled to levels as low as can be reasonably achieved; New Jersey Hazardous Substance Fact Sheet -- Benzo(a)Pyrene -- Micromedex, Inc., 1974-1998.) Water: Sources and Occurrences According to a National Academy of Sciences (NAS) report (Petroleum in the Marine Environment, NAS 1975), about 6 million tons of petroleum hydrocarbons enter the oceans annually; the major contributors are marine transportation and runoff (urban and river). Other sources of PAHs in the oceans are coastal refineries, industrial and domestic waste, natural seeps, and atmospheric fallout. BaP levels found in water are shown in Table 6 (after Osborne and Crosby, Table 17.5, p. 307). These.particles will fall slowly to the bottom, and thus PAH compounds are removed from solution. -Tlie levels of BaP reported in sediments on the other hand can be rather high in the order of ug/kg or even mg/kg of dry sample. As one can see, the levels vary significantlyy depending upon the sampling location and the type of water, but in general they are rather low. This is not unexpected since PAH compounds in solution are readily adsorbed on to the surface of dust, soil or other insoluble particles. -4-

I-' L F I I 1*. Table 6. BaP levels in water. Sample Country BaP (ng/L) Tap water FRG 0.25 - 9 Tap water USA 0.2 - 1.6 Groundwater FRG 1 - 10 Groundwater USA 0.2 Rainwater FRG 4 - 80 Reservoirs UK 0.7 - 3.8 Wellwater UK 0.2-0.6 Well water FRG 2- 15 Lake.Erie USA 0.3 River Rhine at Mainz FRG 50 - 110 River Rhine at Koblenz FRG 10 - 60 River Thames UK 170 - 280 River Thames UK 4.2 - 430 River Trent UK 5.3 - 504 River Severn UK 1.5 - 48 Ohio River USA 5.6 Delaware River USA 41.1 Motorway run-off UK 570 Domestic effluent FRG 38 Human urine 1300 Sewage sludge FRG 1.7 (mg/kg)

Soil: Sources and Occurrences L The majority of investigations of PAHs in soils have been carried out by Soviet i r i I investigators between 1967-1977; these papers only reported the BaP content (Osborne and Crosby, 1987). The concentrations of BaP measured in the U.S.S.R. ranged from 0.0008 mg/kg to 200 mg/kg, with the maximum value found in the vicinity, of an oil refinery. Similarly high concentrations (650 mg/kg) were measured in the area of a carbon black factory. In samples of sandy and forest soil collected in West Germany, considerably lower concentrations of BaP, ranging from 0.001 to 0.0004 mg/kg, were found. The contamination of soil can be attributed almost exclusively to emissions from combustion processes. In the majority of surface soil samples taken in Iceland, where hardly any fossil fuels are burnt, the most commonly found PAHs were not detected (detection limit for BaP, e.g., 0.02,ug/kg soil). Soil samples taken at the Reykjavik, Iceland airport, however, were extremely contaminated, with BaP concentrations reaching 0.785 mg/kg. "Human Exposure to Benzo(a)pyrene" Hattemer-Frey and Travis (1991) used a multimedia transport model to evaluate environmental partitioning of BaP. Measured and predicted environmental concentrations were used to estimate the accumulation of BaP in the food chain and the subsequent extent of human exposure from inhalation and ingestion. Their results showed that the food chain is the dominant pathway of human exposure, accounting for about 97% of the total daily intake of BaP. See Table 7.

F Table 7. Pathways of human exposure to B(a)P (after IIattemer-Frey and Travis, 1991). Source Dailv intake (E.ccg/day) % of total daily intake Food (total) 2.1 97 Inhalation 0.05 2 Water 0.01 1 TOTAL 2.16 100 F I I I I I Ii

i I-- This value of approximately 2.2,ug/day average daily intake of BaP is in agreement with other values reported in the literature (e.g., Suess,1976). Hattemer-Frey and Travis (1991) then went on to discuss human exposure to BaP from smoking and indoor air pollution, referencing a paper by Butler and Crossley (1979) that reportedly estimated that one cigarette delivers approximately 39 ng of BaP. Further, Hattemer-Frey and Travis used in their calculations an estimate that the average smoker smokes 20 cigarettes per day. Based on these calculations, they suggested that the smoker receives an additional 780 ng/day (0.78 ,ug/day) BaP from smoking. Additionally, they again referenced Butler and Crossley (1979), who reported that concentrations of BaP measured indoors (2.2 ng/m3) were comparable to outdoor air concentrations (2.5 ng/m3); thus, indoor activities would not substantially.increase the BaP intake, since inhalation is not a major pathway of human exposure to BaP. Mainstream smoke concentrations of 9.2 ng BaP/cigarette have been reported for the Kentucky Reference Cigarette 1R4F (R.J. Reynolds, 1988). The value for a filtered cigarette could be rounded to 10 ng BaP/cigarette. Thus, an average (1 pack/day) smoker of filtered cigarettes would be exposed to an additional 0.2 ,ug/day of BaP, a level which is approximately 4 times the estimated daily intake of BaP by inhalation. [See Table 8] However, one should keep in mind that more than 90% of the daily intake of BaP is derived from other sources, primarily food. r This can be examined from the perspective of the daily lung burden as described by O O\ . O Chen and Thilly (1996). Instead of using the value of 10 m3/day for breathing, the more widely used ~ W value of 20 m3/day will be chosen. The value of 2.5 ng BaP/m3 as the "urban air concentration" will ~ ~ -6-

Table 8. Estimated exposure of a smoker to BaP (ng/day). Cigarettes/day 10 20 40 1R4F filtered cigarette 100 200 400 I' F

be used, which, as shown in Table 9, is probably an over-estimation of the urban air BaP I concentration in the 1990s, if the downward trend has continued. Using the formula (breathing rate/day X urban air BaP level) = ng BaP by inhalation/day, for a breathing rate of 20 m3/day X 2.5 ng BaP/m3 = 50 ng BaP/day or 0.05 gg/day by inhalation/day. The level of 0.05 ug/day by inhalation corresponds to what Hattemer-Frey and Travis reported [See Table 71. Examining BaP Exposure from ETS or Room-Aged Sidestream Smoke (RASS) Attributing levels of PAH (BaP) in the air of restaurants, public rooms, etc., to ETS is difficult since other sources may be present, and other factors, such as ventilation rates, number of smokers, etc., may confound the issue. However, Grimmer (1983), under controlled conditions, reported 22 ng/m3 BaP where cigarettes were being smoked and less than 3 ng/m 3 where no cigarettes were being smoked. He calculated that ETS contributed about 7 times the background BaP level. Grimmer states that "the measured concentrations of 22 ng BaP per cubic meter has to be considered as a maximum BaP concentration attainable by smoking. In practice nobody would tolerate this concentration" of smoke due to eye irritation, etc. ' A 12-month inhalation study in rats using room-aged sidestream smoke (RASS) (INBIFO, data enclosed) reports the following concentrations of BaP in RASS from 1R4F cigarettes: 0.13 ,ug/m3 (upper limit) for the whole-body 12-month exposure group, and 0.121 gg/m3 (upper -7-

L I ( F F I Table 9. Average BaP concentrations (ng/m3) in U.S. urban and rural areas during 1966-1977 (after Pucknat 1981, Table 5.14, p. 168). Location Year 1966 1970 1976 Urban 3.2 2.1 0.5 Rural 0.4 0.2 0.1

limit) for the head-only 12-month exposure group (Haussmann et al., 1998). Again, if we consider urban ambient air to contain an average of 2.5 ng/m3 BaP, one can see that the rats in this study were exposed to approximately 50 times the level of BaP found in ambient air. The RASS concentrations in this study were approximately 100-fold higher than the maximum of the average concentrations of respiratory suspended particles (RSP) reportedly attributable to ETS (Guerin et al., 1992; U.S. EPA, 1992; Jenkins et al:, 1996). Thus, if one assumes that BaP, which is in the particulate phase, tracks with RSP, then 0.13 µg/m3 would correspond to 0.0013 ~zg/m3. From the perspective of human exposure, this level of exposure would be equivalent to 0.0013 ,ug/m' X 20 m3/day = 0.026 gg/ or 26 ng/day, which is about half the daily level by inhalation estimated by Hattemer-Frey and Travis. i I I -8-

References r F r i L I F i i Butler, J.D., and Crossley, P., An appraisal of the relative airborne sub-urban concentrations of polycyclic aromatic hydrocarbons monitored indoors and outdoors, The Science of the Total Environment 11: 53-58 (1979). , Chen, J., and Thilly, W.G., Mutational spectra vary with exposure conditions: benzo[a]pyrene in human cells. Mutation Research 357: 209-217 (1996). Grimmer, G.,' Chapter 3--. Sources and occurrence of polycyclic aromatic hydrocarbons. In: IARC Environmental Carcinogens, Selected Methods ofAnalysis, Vol. 3--Analysis of Polycyclic Aromatic Hydrocarbons in Environmental Samples. H. Egan (Ed.). IARC, Lyon, pp. 31-54 (1979). Grimmer, G., and Pott, F. Occurrence of PAH. In: Environmental Carcinogens: Polycyclic Aromatic Hydrocarbons. G. Grimmer (Ed.). CRC Press, Inc., Boca Raton, FL, p. 61-128 (1983). Guerin, M.R., Jenkins, R.A., and Tomkins, R.A. The Chemistry of Environmental Tobacco Smoke: Composition and Measurement. Center for Indoor Air Research, Lewis Publishers, Chelsea, MI (1992) Hattemer-Frey, H.A., and Travis, C.C., Benzo-a-Pyrene: Environmental Partitioning and Human Exposure, Toxicology and Industrial Health 7(2): 141-157 (1991). Haussmann, H.J, et al., Comparison of fresh and room-aged cigarette sidestrearn smoke in a subchionic inhalation study on rats. Toxicological Sciences 41: 100-116 (1998). International Agency for Research on Cancer (IARC), IARC Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans, Polynuclear Aromatic Hydrocarbon Compounds, Part 1, Chemical, Environmental and Experimental Data. IARC, Lyon, Vol. 32, pp. 211-224; pp. 36-37 (1983). International Agency for Research on Cancer (IA.RC), IARC Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans, Biological Data Relevant in the Evaluation of. Carcinogenic Risk to Humans. Tobacco Smoking. IARC, Lyon, Vol. 38, pp. 3 89-394 (1986a). International Agency for Research on Cancer (IARC), L4RC Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans, Biological Data Relevant in the Evaluation of Carcinogenic Risk to Humans. Tobacco Smoking. IARC, Lyon, Vol 38., pp. 101-102 (1986b). Jenkins, R.A., et al., Exposure to tobacco smoke in sixteen cities in the United States as determined by personal breathing zone air sampling. JExpos Analysis Environ Epidemiol 6: 473-502 (1996). -9-