A comparison on the emission of polycyclic aromatic hydrocarbons and their corresponding carcinogenic potencies from a vehicle engine using leaded and lead-free gasoline. (Articles).Our objective in this study was to assess the effect of using two kinds of lead-free gasoline gasoline or petrol, light, volatile mixture of hydrocarbons for use in the internal-combustion engine and as an organic solvent, obtained primarily by fractional distillation and "cracking" of petroleum, but also obtained from natural gas, by [including 92-lead-free gasoline (92-LFG) and 95-lead-free gasoline (95-LFG), rated according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. their octane oc·tane n. 1. Any of various isomeric paraffin hydrocarbons with the formula C8H18, found in petroleum and used as a fuel and solvent. 2. An octane number. levels] to replace the use of premium leaded gasoline (PLG PLG Plasminogen PLG Poly(Lactide-co-Glycolide) PLG Progressive Librarians Guild PLG Private/Light Goods (UK vehicle taxation class) PLG Programming Languages Group PLG Professional Liability Group ) on the emissions of polycyclic aromatic hydrocarbons polycyclic aromatic hydrocarbon n. Any of a class of carcinogenic organic molecules that consist of three or more rings containing carbon and hydrogen and that are commonly produced by fossil fuel combustion. (PAHs) and their corresponding benzo[a]pyrene equivalent (Ba[P.sub.eq]) amounts from the gasoline-powered engine. The results show that the three gasoline fuels originally contained similar total PAHs and total Ba[P.sub.eq] contents; however, we found significant differences in the engine exhausts in both contents. The above results suggest that PAHs originally contained in the gasoline fuel did not affect the PAH PAH, PAHA aminohippuric acid. PAH abbr. para-aminohippuric acid PAH 1 Polycyclic aromatic hydrocarbon, see there 2. Pulmonary artery HTN emissions in the engine exhausts. The emission factors An emission factor can be defined as the average emission rate of a given pollutant for a given source, relative to units of activity. Emission factors can be used to derive estimates of gas emissions (for instance, greenhouse gas emissions) based on the amount of fuel combusted of both total PAHs and total Ba[P.sub.eq] obtained from the three gasoline fuels shared the same trend: 95-LFG > PLG > 92-LFG. The above result suggests that when PLG was replaced by 95-LFG, the emissions would increase in both total PAHs and total Ba[P.sub.eq], but when replaced by 92-LFG would lead to the decreased emissions of both contents. By taking emission factors and their corresponding annual gasoline consumption rates into account, we found that both total PAH and total Ba[P.sub.eq] emissions increased from 1994 to 1999. However, the annual increasing rates in total Ba[P.sub.eq] emissions were slightly-higher than the corresponding increasing rates in total PAHs. Key words: benzo[a]pyrene equivalent concentration, engine exhaust, lead-free gasoline, polycyclic aromatic hydrocarbons, premium leaded gasoline. Environ en·vi·ron tr.v. en·vi·roned, en·vi·ron·ing, en·vi·rons To encircle; surround. See Synonyms at surround. [Middle English envirounen, from Old French environner Health Perspect 109:1285-1290 (2001). [Online 30 November 2001] http://ehpnet1.niehs.nih.gov/docs/ 2001/109p1285-1290mi/abstract.html ********** The premium leaded gasoline (PLG) and two kinds of lead-free gasoline [including 92 lead-free gasoline (92-LFG) and 95 lead-free gasoline (95-LFG) so called for their octane levels] are the three major fuels currently used in Taiwan area for spark-ignition engine vehicles. Recently worldwide efforts to reduce the use of PLG are intended to lower lead emission into the atmosphere and eventually to reduce the lead level in human blood. In Taiwan, the annual PLG consumption rates decreased significantly from 2,599 x [10.sup.6] L/year in 1994 to 944 x [10.sup.6] L/year in 1999. On the other hand, the annual consumption rates of 92-LFG and 95-LFG increased significantly from 1,321 x [10.sup.6] L/year and 3,485 x [10.sup.6] L/year in 1994, to 2,136 x [10.sup.6] L/year and 6,118 x [10.sup.6] L/year in 1999, respectively (Table 1). As a result, one-ring aromatic hydrocarbon Noun 1. aromatic hydrocarbon - a hydrocarbon that contains one or more benzene rings that are characteristic of the benzene series of organic compounds benzene, benzine, benzol - a colorless liquid hydrocarbon; highly inflammable; carcinogenic; the simplest of the in LFG LFG Landfill Gas LFG Lincoln Financial Group (insurance & financial planning company) LFG Looking For Group (Everquest) LFG Lexical-Functional Grammar (computational linguistics) fuels were added to maintain the knock resistance of vehicle engine (1). An important question, therefore, is whether the use of LFG in replacing PLG will increase emissions of some toxic substances, such as polycyclic aromatic hydrocarbons (PAHs), from gasoline-fueled engines. PAHs and their derivatives are associated with the incomplete combustion of organic material, arising partly from natural combustion, such as forest fires This is a list of notorious forest fires: North America Year Size Name Area Notes 1825 3,000,000 acres (12,000 km²) Miramichi Fire New Brunswick Killed 160 people. and volcanic eruptions volcanic eruptions discharging of fumes, dust and lava from volcanoes. They have damaging potential in addition to those of being physically overpowering by the lava flow or the ash or dust fallout. ; but most emissions arise from anthropogenic an·thro·po·gen·ic adj. 1. Of or relating to anthropogenesis. 2. Caused by humans: anthropogenic degradation of the environment. activities, such as the burning of gasoline in motor vehicles (2-4). For gasoline-powered engines, the emission of PAHs occurs through many factors, including the chemical compositions of the fuels, the types of lubricant Lubricant A gas, liquid, or solid used to prevent contact of parts in relative motion, and thereby reduce friction and wear. In many machines, cooling by the lubricant is equally important. and fuel additives, and the engine's operating conditions (1,5-7). However, the emission of PAHs in the above studies was assessed on the basis of total PAH concentration, without taking the carcinogenic carcinogenic having a capacity for carcinogenesis. potency potency /po·ten·cy/ (po´ten-se) 1. the ability of the male to perform coitus. 2. the relationship between the therapeutic effect of a drug and the dose necessary to achieve that effect. 3. of each individual PAH compound into account. To date, the International Agency for Research on Cancer The International Agency for Research on Cancer (IARC, or CIRC in its French acronym) is an intergovernmental agency forming part of the World Health Organisation of the United Nations. Its main offices are in Lyon, France. (IARC) has classified several PAH compounds into probable (2A) or possible (2B) human carcinogens Carcinogens Substances in the environment that cause cancer, presumably by inducing mutations, with prolonged exposure. Mentioned in: Colon Cancer, Rectal Cancer (8). In principle, the carcinogenic potency of a given PAH compound can be assessed based on its benzo[a]pyrene equivalent concentration (Ba[P.sub.eq]). Calculation of Ba[P.sub.eq] concentration for a given PAH compound requires the use of its toxic equivalent factor (TEF TEF Tracheoesophageal fistula, see there )--which represents the relative carcinogenic potency of the given PAH compound by reference to the specific compound BaP--to adjust its original concentration. To date, only a few proposals for TEFs are available (9-11). Among them, the list of TEFs completed by Nisbet and LaGoy in 1992 (11) (Table 2) reflects well the actual state of knowledge on the toxic potency of each individual PAH compound (12). On the basis of this TEFs list, the carcinogenic potency of total PAHs can be assessed by the sum of the Ba[P.sub.eq] concentrations estimated for each PAH compound in total PAHs. In this study we aimed first to assess the effect on PAH emissions when different types of LFG replaced PLG in a test gasoline-powered engine. Assuming that PAH compositions in the engine exhaust might be affected by the types of gasoline fuel used in the test engine, we further assessed total Ba[P.sub.eq] concentrations in engine exhaust as a possible health risk. The results obtained from this study will enhance further examination of the appropriate type of LFG to replace PLG. Materials and Methods Engine and dynamometer dynamometer /dy·na·mom·e·ter/ (di?nah-mom´e-ter) an instrument for measuring the force of muscular contraction. dy·na·mom·e·ter n. An instrument for measuring the degree of muscular power. system. The gasoline-powered engine (noncatalyst) used in this study was a Mazda E5 engine with an odometer odometer (ōdŏm`ĭtər), instrument provided in an automotive vehicle to indicate the total number of miles that have been traveled. reading of approximately 100,000 km. The test engine was a four-cylinder carburetor with the ignition ignition, apparatus for igniting a combustible mixture. The German engineer Nikolaus A. Otto, in his first gas engine, used flame ignition; another method was heating a metal tube to incandescence. order of 1-3-4-2, bore and stroke of 77 x 80 [mm.sup.2], swept volume of 1,490 [cm.sup.3], power generation rate of 6.88 kW/1,500 rpm, and compression ratio compression ratio Degree to which the fuel mixture in an internal-combustion engine is compressed before ignition. It is defined as the volume of the combustion chamber with the piston farthest out divided by the volume with the piston in the full-compression position ( of 9:1. The engine was installed and operated on a dynamometer (Model FE 60-100-150S; Borghi & Saveri Corp, Bologna Bologna (bōlô`nyä), city (1991 pop. 404,378), capital of Emilia-Romagna and of Bologna prov., N central Italy, at the foot of the Apennines and on the Aemilian Way. , Italy). The engine was adjusted at the laboratory of the manufacturer before the first experiment was conducted. Before each set of experiments, both the lubricating oil and the oil filter were changed and the fuel tank was emptied. The tank was filled with 20 L fuel, and then the engine was conditioned by simulating a cruising distance of approximately 55 km at a speed of 110 km/hr (rotary speed 3,000 rpm). To eliminate the effect of the type of lubricant on the performance of the test engine, only one commercially available synthetic engine lubricating oil was used (Super-2170; Chinese Petroleum Co., Taipei, Taiwan) in this study. The rotary speeds of 1,000, 1,500, 2,100, and 3,000 rpm simulated the four specified operating conditions of idling and the three cruising speeds cruising speed n → velocidad f de crucero cruising speed n → vitesse f de croisière cruising speed cruise n of 40 km/hr, 80 km/hr, and 110 km/hr, respectively. Under these four operating conditions, the throttle throttle Valve for regulating the supply of a fluid (as steam) to an engine, especially the valve controlling the volume of vaporized fuel delivered to the cylinders of an internal-combustion engine. In an automobile engine, gasoline is held in a chamber above the carburetor. opening fractions of the air valve a valve to regulate the admission or egress of air; esp. a valve which opens inwardly in a steam boiler and allows air to enter. etc. See under Air. Ball, Check, etc. See also: Air Valve were 0%, 20%, 30%, and 40%, the eddy currents Eddy current An electric current induced within the body of a conductor when that conductor either moves through a nonuniform magnetic field or is in a region where there is a change in magnetic flux. It is sometimes called Foucault current. on the dynamometer were 1.1, 2.6, 2.6, and 2.3 Amp, and the torques tor·ques n. Zoology A band of feathers, hair, or coloration around the neck. [Latin torqu were 0.79, 4.44, 4.39, and 4.32 kg/m, respectively. We performed three runs of the experiment under each of the prescribed pre·scribe v. pre·scribed, pre·scrib·ing, pre·scribes v.tr. 1. To set down as a rule or guide; enjoin. See Synonyms at dictate. 2. To order the use of (a medicine or other treatment). operating conditions. Gasoline fuels. We tested three gasoline fuels currently used most often in Taiwan, including PLG, 92-LFG, and 95-LFG (Table 3). For each set of experiments, we determined the volume of gasoline fuel before and after the experiment to obtain the net amount of fuel consumed. Also, before each set of experiments was conducted, we collected three 10-mL gasoline samples for PAH analysis. The fuel consumption rates, inlet inlet /in·let/ (-let) a means or route of entrance. pelvic inlet the upper limit of the pelvic cavity. thoracic inlet the elliptical opening at the summit of the thorax. airflow rates, and exhaust gas Exhaust gas is flue gas which occurs as a result of the combustion of fuels such as natural gas, gasoline/petrol, diesel, fuel oil or coal. It is discharged into the atmosphere through an exhaust pipe or flue gas stack. flow rates obtained for each of the three gasoline fuels operated under each of the four specified operating conditions are shown in Table 4. PAH sampling system for engine exhaust. Because PAHs contained in engine exhaust gases are semivolatile, measurements for both particle-phase and gas-phase PAHs were necessary. We used a PAH sampling system (PSS See EPSS. ; Bectech Group Ltd. Co., Taipei, Taiwan) to meet the above requirement. The PSS was equipped with a dilution pipe (internal diameter 30 cm) which was connected to the engine tail pipe, and from which the exhaust gas was drawn, diluted di·lute tr.v. di·lut·ed, di·lut·ing, di·lutes 1. To make thinner or less concentrated by adding a liquid such as water. 2. To lessen the force, strength, purity, or brilliance of, especially by admixture. , cooled, and then collected. The dilution factor of pollutants pollutants see environmental pollution. in the dilution pipe was approximately 25. A pump was installed behind the flow meter flow meter Device that measures the velocity of a gas or liquid. It has applications in medicine as well as in chemical engineering, aeronautics, and meteorology. Examples include pitot tubes, venturi tubes, and rotameters (tapered graduated tubes with a float inside that is to draw the gas sample from the dilution pipe. We used a sampling probe with a filter holder to collect particle-phase PAHs in the diluted exhaust. A cooling device was installed after the filter holder to ensure the temperature of gas was below 31 [degrees] C to prevent the revolatization of lower molecular-weight PAHs from the glass cartridge (1) See phono cartridge. (2) A removable storage module that contains magnetic disks, optical discs, magnetic tape or memory chips. Cartridges are inserted into slots in the drive, printer or computer. . The glass cartridge contained three sections, including a 5-cm polyurethane foam Noun 1. polyurethane foam - a foam made by adding water to polyurethane plastics polyfoam polyurethan, polyurethane - any of various polymers containing the urethane radical; a wide variety of synthetic forms are made and used as adhesives or plastics or (PUF PUF Public Use File PUF Parallel URL fetcher (*nix download tool) PUF Physically Unclonable Function PUF Northern Puffer PUF Paid-Up-Front PUF Preguntas de Uso Frequente (Spanish: Frequently Asked Questions) ) plug, followed by 2.5 cm of XAD-2 resin, and finally supported by a 2.5-cm PUF plug. Silicon glue was used to seal and hold the two PUF plugs to prevent XAD-2 resin from leaking out during sampling. The PAH compounds collected by the glass cartridge comprised the gas-phase PAHs. In this study, the operational flow rates of the PSS were specified at 4.5-5.5 L/min. Before sampling, we cleaned the glass fiber filter with distilled deionized water Deionized water (DI water or de-ionized water; also spelled deionised water, see spelling differences) is water that lacks ions, such as cations from sodium, calcium, iron, copper and anions such as chloride and bromide. and n-hexane, and placed it in an oven at 450 [degrees] C for 8 hr to burn off organic compounds that might have been contained in the filters. Finally, the glass fiber filter was stored in a prebaked glass box and wrapped with hexane-washed aluminum foil Noun 1. aluminum foil - foil made of aluminum aluminium foil, tin foil foil - a piece of thin and flexible sheet metal; "the photographic film was wrapped in foil" . The cartridge was first soaked soak v. soaked, soak·ing, soaks v.tr. 1. a. To make thoroughly wet or saturated by or as if by placing in liquid. b. To immerse in liquid for a period of time. 2. in distilled water Noun 1. distilled water - water that has been purified by distillation H2O, water - binary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 degrees centigrade and boils above 100 degrees centigrade; and methanol methanol, methyl alcohol, or wood alcohol, CH3OH, a colorless, flammable liquid that is miscible with water in all proportions. Methanol is a monohydric alcohol. It melts at −97. dichloromethane for 1 day and then soaked in n-hexane for 4 days. When the glass cartridge was placed in a vacuum oven A vacuum oven is a sealed chamber in which the pressure is lowered and the temperature is raised. One use of such an oven is to remove volatiles and bound gases from surfaces. Another is to heat a substance in an oxygen-poor environment to reduce oxidation. at 60 [degrees] C for 2 hr to evaporate e·vap·o·rate v. 1. To convert or change into a vapor; volatilize. 2. To produce vapor. 3. To draw or pass off in the form of vapor. 4. residual solvent. Finally, the cartridge was wrapped by hexane-washed aluminum foil and stored in clean screw-capped jars with Teflon cap liners liners, n the liquid material applied to teeth to protect them within a cavity preparation, to seal carious tissues, or to release beneficial chemicals such as fluoride. . We performed breakthrough tests on a two-layer XAD-2 cartridge with the sequence PUF-1, XAD-2-1, PUF-2, XAD-2-2, and PUF-3. After sampling, we analyzed an·a·lyze tr.v. an·a·lyzed, an·a·lyz·ing, an·a·lyz·es 1. To examine methodically by separating into parts and studying their interrelations. 2. Chemistry To make a chemical analysis of. 3. the PAH concentrations of the two XAD-2 resin layers and the three PUF plugs. In three breakthrough tests, we found no significant amounts of PAHs in the XAD-2-2 resin, PUF-2, and PUF-3 sections. PAH analysis. After sampling, both glass fiber filter and cartridge were Soxhlet extracted with a mixed solvent (n-hexane and dichloromethane, v:v = 1:1,500 mL each) for 24 hr. The extract was concentrated by purging Purging The use of vomiting, diuretics, or laxatives to clear the stomach and intestines after a binge. Mentioned in: Anorexia Nervosa purging (purj´ing), n with ultrapure nitrogen (flow rate 1.0 L/min) to 2 mL, which was followed by the cleanup procedure to remove pollutants that would coelute with PAHs from the gas chromatography gas chromatography (GC) Type of chromatography with a gas mixture as the mobile phase. In a packed column, the packing or solid support (held in a tube) serves as the stationary phase (vapour-phase chromatography, or VPC) or is coated with a liquid stationary phase (GC) column. The cleanup procedure was done in a cleanup column. The column (internal diameter 1 cm) contained approximately 5 g glasswool at the bottom, filled by 17 g 6% deactivated silica gel silica gel, chemical compound. It is a colloidal form of silica, and usually resembles coarse white sand. It may be prepared by partial dehydration of metasilicic acid, H2SiO3. Because it has many tiny pores, it has great adsorptive power. (mixed with 60 mL n-hexane) in the middle section, and topped with 1 cm of anhydrous an·hy·drous adj. Without water, especially water of crystallization. anhydrous (anhī´drus), adj without water. anhydrous containing no water. sodium sulfate sodium sulfate, chemical compound, Na2SO4. It is a white, orthorhombic crystalline compound at ordinary temperatures; above 100°C; it assumes a monoclinic structure, and above about 250°C; it assumes a hexagonal structure. . Before cleanup, we added 60 mL n-hexane to wash the sodium sulfate and the silica gel. Just before the sodium sulfate layer was exposed to the air, the elution elution /elu·tion/ (e-loo´shun) in chemistry, separation of material by washing; the process of pulverizing substances and mixing them with water in order to separate the heavier constituents, which settle out in solution, from the of n-hexane was stopped and the eluant el·u·ant or el·u·ent n. A substance used as a solvent in the process of elution. was discarded dis·card v. dis·card·ed, dis·card·ing, dis·cards v.tr. 1. To throw away; reject. 2. a. To throw out (a playing card) from one's hand. b. . During cleanup, the concentrated sample was transferred onto column, and the wall of vessel was rinsed twice with 2 mL n-hexane which was also added to the column. Then, 200 mL 6% ethylether in n-hexane was added to the column and allowed to flow through the column at a rate of 3-5 mL/min, and the eluant was collected. The collected eluant from the cleanup procedure was reconcentrated to 0.5 mL with nitrogen. We used a GC (model 5890A; Hewlett-Packard, Wilmington, DE, USA) with a Hewlett-Packard capillary capillary (kăp`əlĕr'ē), microscopic blood vessel, smallest unit of the circulatory system. Capillaries form a network of tiny tubes throughout the body, connecting arterioles (smallest arteries) and venules (smallest veins). column (HP Ultra 2, 50 m x 0.32 mm x 0.17 [micro]m), a mass selected detector (MSD (MicroSoft Diagnostics) A utility that accompanied Windows 3.1 and DOS 6 that reported on the internal configuration of the PC. A variety of information on disks, video, drivers, IRQs and port addresses was provided. ) (Hewlett-Packard model 5972), and a computer workstation for the PAH analysis. We determined the masses of molecular and fragment ions of PAHs using the scan mode for pure PAH standards. We identified PAHs using the selected ion monitoring (SIM) mode. The GC/mass spectrometer spectrometer Device for detecting and analyzing wavelengths of electromagnetic radiation, commonly used for molecular spectroscopy; more broadly, any of various instruments in which an emission (as of electromagnetic radiation or particles) is spread out according to some (MS) was calibrated cal·i·brate tr.v. cal·i·brat·ed, cal·i·brat·ing, cal·i·brates 1. To check, adjust, or determine by comparison with a standard (the graduations of a quantitative measuring instrument): with a diluted standard solution of 16 PAH compounds (PAH Mixture-610M; Supelco, Bellefonte, PA, USA) plus five additional individual PAHs obtained from Merck (Darmstadt, Germany). These 21 PAH compounds include naphthalene naphthalene (năf`thəlēn'), colorless, crystalline, solid aromatic hydrocarbon with a pungent odor. It melts at 80°C;, boils at 218°C;, and sublimes upon heating. (Nap), acenaphthylene (AcPy), acenaphthene (Acp), fluorene (Flu), phenanthrene phenanthrene /phe·nan·threne/ (fe-nan´thren) a tricyclic aromatic hydrocarbon occurring in coal tar; toxic and carcinogenic. phe·nan·threne n. (PA), anthracene anthracene (ăn`thrəsēn), C14H10, solid organic compound derived from coal tar. It melts at 218°C; and boils at 354°C;. (Ant ant, any of the 2,500 insect species constituting the family Formicidae of the order Hymenoptera, to which the bee and the wasp also belong. Like most members of the order, ants have a "wasp waist," that is, the front part of the abdomen forms a narrow stalk, called ), fluoranthene (FL), pyrene (Pyr), cyclopenta[c,d]pyrene (CYC), benz[a]anthracene (BaA), chrysene (CHR CHR canine hypoxic rhabdomyolysis. ), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[e]pyrene (BeP), benzo[a]pyrene (BaP), perylene (PER), indeno[1,2,3,-cd]pyrene (IND), dibenz[a,h]anthracene (DBA), benzo[b]chrysene (BbC), benzo[ghi] perylene (BghiP), and coronene (COR). Analysis of serial dilutions of PAH standards showed the limit of detection (LOD Lod (lōd), city (1994 pop. 51,200), central Israel. It is also known as Lydda. Its manufactures include paper products, chemicals, oil products, electronic equipment, processed food, and cigarettes. ) of GC/MS GC/MS Gas Chromatograph/Mass Spectrometer GC/MS Gas Chromatograph/Mass Spectrometry GC/MS Gas Chromatograph/Mass Spectrograph was 0.023-0.524 ng. The limit of quantification (LOQ LOQ Limit of Quantitation LOQ Limit Of Quantification LOQ Loquitur (Latin: speaks) LOQ Level of Quantification LOQ List Of Questions LOQ Laugh Out Quiet LOQ Leadership Opinion Questionaire ) was defined as the limit of detection divided by the sampling volume for the PSS. The LOQ for PAH compounds was 0.077-1.75 ng/[m.sup.3]. Ten consecutive injections of a PAH 610-M standard yielded an average relative standard deviation In probability theory and statistics, the Relative Standard Deviation (RSD or %RSD) refers to the absolute value of the coefficient of variation expressed as a percentage. It is widely used in analytical chemistry to express the precision of an assay. l (RSD RSD Reflex sympathetic dystrophy, see there ) of GC/MS integration area of 3.0% (range 0.8-5.1%). We determined PAH recovery efficiencies by spiking the filter/cartridge with solutions containing known PAH concentrations through the same experimental procedure applied to the field samples. The recovery efficiency of PAHs varied between 0.736 and 1.15 and averaged 0.859. The recovery efficiency yielded for the two internal standards PA-d10 and PER-d12 was between 0.78 and 0.88. The blank tests for PAHs were accomplished by the same procedure as the recovery-efficiency tests without adding the known standard solution before extraction. Analyses of field blanks, including filters and cartridges
Results and Discussion PAH and its corresponding Ba[P.sub.eq] concentration originally contained in gasoline fuels. We collected six samples from each of the three gasoline fuels (i.e., PLG, 92-LFG, and 95-LFG) for PAH analyses (Table 5). The results show that the concentrations for each individual PAH compound, total PAHs, individual Ba[P.sub.eq], and total Ba[P.sub.eq] among the three gasoline fuels were comparable (t-test, p-value < 0.05). The concentrations of total PAHs and total Ba[P.sub.eq] for PLG, 92-LFG, and 95-LFG were 13.8, 16.9, and 15.0 mg/L, and 0.09, 0.11, and 0.10 mg/L, respectively. Total PAHs obtained for PLG, 92-LFG, and 95-LFG were contributed mostly by Nap, which accounted for 83%, 76%, and 77% of total PAHs for the three types of gasoline fuel, respectively. However, total Ba[P.sub.eq] was contributed mainly by the three carcinogenic compounds--BaP, IND, and DBA--and their sum accounted for 74%, 74%, and 72% of total Ba[P.sub.eq] for the three types of gasoline fuel, respectively. These results clearly indicate that the three gasoline fuels contained not only similar PAH compositions, but also similar carcinogenic potencies. PAHs contained in engine exhaust. In this study, the test engine was operated under four specified operating conditions, including idling, and three cruising speeds of 40 km/hr, 80 km/hr, and 110 km/hr for each of the three gasoline fuels. For each set of experiments (i.e., the test engine was filled with one specific type of gasoline fuel and operated under one specific operating condition), we collected three samples from the engine exhaust by using the PSS. The mean concentrations (micrograms per cubic meter Noun 1. cubic meter - a metric unit of volume or capacity equal to 1000 liters cubic metre, kiloliter, kilolitre metric capacity unit - a capacity unit defined in metric terms ) obtained for each of the 21 PAH compounds and the total PAHs (micrograms per cubic meter) are shown in Table 6. Total PAH concentrations for each of the three gasoline fuels operated under the four specified operating conditions were not consistent. The magnitude of total PAHs presented in sequences for PLG, 92-LFG, and 95-LFG operated under the four specified operating conditions were, respectively, 110 km/hr > 40 km/hr > 80 km/hr > idling; 80 km/hr > 110 km/hr > idling > 40 km/hr; and 110 km/hr > 40 km/hr > 80 km/hr > idling. These results are not surprising because the fuel consumption rates and inlet air flow rates were different for the three types of gasoline fuel when operated under the four specified operating conditions (Table 4). Moreover, given that the exhaust gas flow rates were also different (Table 4), the above total PAH concentrations were not adequate to describe the amount of PAH emission for each of the three types of gasoline fuel when operated under each of the four specified operating conditions. Table 6 also shows the emission factors for total PAHs (i.e., E[F.sub.PAHs], micrograms per liter liter, abbr. l, unit of volume in the metric system, defined since 1964 as equal to 0.001 cubic meters, or 1 cubic decimeter. A cube that has each of its edges equal to 10 centimeters has a volume of 1 liter. The liter is equal to 1.057 liquid quarts, 0. of fuel) for each of the three types of gasoline fuel when operated under each of the four operating conditions. Here, E[F.sub.PAHs], was defined as the amount of total PAHs (micrograms) expelled from the test engine when 1 L of gasoline fuel was consumed, and was calculated based on the following equation: E[F.sub.PAH] = [(Total PAHs)x(Exhaust gas flow rate)x[10.sup.-3]]/ [(Fuel consumption rate) x 1/60] From this equation, total PAHs (micrograms per cubic meter) can be found in Table 6, and the exhaust gas flow rate (liters per minute) and the fuel consumption rate (liters per hour) can be seen in Table 4. The results show the magnitude of E[F.sub.PAH] presented in sequence for the four specified operating conditions shared the same trend as 95-LFG > PLG > 92-LFG. Because the three types of gasoline fuel contain similar PAH concentrations (Table 5), the above results suggest that PAHs originally contained in gasoline fuels did not affect PAH emissions in the engine exhaust. PAHs in the engine exhaust were contributed both by the survival of PAHs originally contained in the fuel and by PAHs generated during pyrosynthesis (13). At this stage, because the mechanisms of survivability sur·viv·a·ble adj. 1. Capable of surviving: survivable organisms in a hostile environment. 2. That can be survived: a survivable, but very serious, illness. and pyrosynthesis of PAHs in the engine are not well understood, the results obtained from this study warrant further research. Ba[P.sub.eq] contained in the engine exhaust. Table 6 shows that Nap contributed to the majority of total PAHs for the three types of gasoline fuel operated under the four specified operating conditions. Therefore, the measurement of total PAHs might be deceptive de·cep·tive adj. Deceptive or tending to deceive. de·cep  tive·ness n. on assessing
the health-risks that associated with total PAH exposures because some
PAH compounds, such as BaP, DBA, BaA, BbF, BkF, and IND, are more
carcinogenic than Nap. Therefore, we must examine further the emission
of Ba[P.sub.eq] as a health risk. Table 7 shows the mean concentrations
of Ba[P.sub.eq]. for each of the 21 PAH compounds and the total
Ba[P.sub.eq] for each type of gasoline when operated under the four
specified operating conditions. The magnitudes of total Ba[P.sub.eq], in
sequence for PLG, 92-LFG, and 95-LFG. were 110 km/hr > 40 km/hr >
80 km/hr > idling; 110 km/hr > 80 km/hr > idling > 40 km/hr;
and 110 km/hr > 80 km/hr > idling > 40 km/hr. At this stage, we
do not have enough knowledge to address the above findings because the
fuel consumption rates and inlet air flow rates were different for the
three types of gasoline fuel operated under the four specified operating
conditions (Table 4), and particularly because the mechanism regarding
the PAH emissions in the engine are not well understood.Table 7 also shows the emission factors for total Ba[P.sub.eq] (i.e., E[F.sub.BaPeq], micrograms per liter of fuel) for each type of gasoline fuel when operated under the four operating conditions. Here, the emission factor E[F.sub.BaPeq] (micrograms per liter of fuel) was defined as the amount of Ba[P.sub.eq] (micrograms) exhausted from the test engine when 1 L of gasoline fuel was consumed, and was calculated based on the following equation: E[F.sub.BaPeq] = [(Total Ba[P.sub.eq])x(Exhaust gas rate)x60]/ [(Fuel consumption rate)x[10.sup.3]] The results show that the magnitude of E[F.sub.BarPeq] presented in sequence for the four specified operating conditions were not consistent. The sequences were 95-LFG > PLG > 92-LFG, for the test gasoline engine gasoline engine: see internal-combustion engine. gasoline engine Most widely used form of internal-combustion engine, found in most automobiles and many other vehicles. when operated under 110 km/hr, 80 km/hr, and idling conditions, and PLG > 95-LFG > 92-LFG when operated at 40 km/hr. Although the three types of fuel originally contained quite similar Ba[P.sub.eq] contents (Table 5), the above results indicate that PAHs originally contained in the fuel did not affect the emission of Ba[P.sub.eq]. One recent study indicated that the combustion process not only might decrease the lower molecular weight PAHs originally contained in raw materials, but also might increase some more toxic compounds, such as BaP, in the exhaust gas (14). At this stage, because the mechanisms regarding the decomposition decomposition /de·com·po·si·tion/ (de-kom?pah-zish´un) the separation of compound bodies into their constituent principles. de·com·po·si·tion n. 1. and pyrosynthesis of PAHs for the gasoline-powered engine are not well understood, the results obtained from this study warrants further research. The effect of using lead-free gasoline on total PAH and Ba[P.sub.eq] emissions. Table 8 shows the annual emission rates (kilograms per year) of total PAHs (i.e., E[R.sub.PAH]) and total Ba[P.sub.eq] (i.e., E[R.sub.BaPeq]) for each type of gasoline from 1994 to 1999. Here, E[R.sub.PAH] and E[R.sub.BaPeq] were calculated according to following equations E[R.sub.PAH] = (Avg E[F.sub.PAH]) x (Fuel consumption rate) x [10.sup.-3] E[R.sub.BaPeq] = (Avg E[F.sub.BaPeq]) x (Fuel consumption rate) x [10.sup.-3], where Avg E[F.sub.PAH] = the averaged E[F.sub.PAH] values for the given type of gasoline operated under the four specified cruising speeds (micrograms per liter of fuel) (Table 6). Ave E[F.sub.BaPeq] = the averaged E[F.sub.BaPeq] values for the given type of gasoline operated under the four specified cruising speeds (micrograms per liter of fuel) (Table 7). The results show the E[R.sub.PAH] for PLG reduced significantly from 9,876 kg/year in 1994 to 3,587 kg/year in 1999. But for 92-LFG and 95-LFG, the ERr, AH increased significantly from 3,580 L/year and 22,234 kg/year in 1994 to 5,798 kg/year and 39,033 kg/year in 1999, respectively. Total E[R.sub.PAH] (i.e., the sum of E[R.sub.PAH] values for the three type of gasoline) increased from 35,690 kg/year in 1994 to 48,409 kg/year in 1999. Obviously, the above results could not be explained simply by the annual consumption rates of the three types of gasoline fuel. The Avg E[F.sub.PAH] (Table 6) for the three types of gasoline fuel also played important roles for E[R.sub.PAH] and total E[R.sub.PAH]. As shown in Table 6, the magnitude of Avg E[F.sub.PAH] presented in sequence for the three types of gasoline was 95-LFG > PLG > 92-LFG (i.e, 6,380 [micro]g/L fuel > 3,800 [micro]g/L fuel > 2,710 [micro]g/L fuel). Therefore, use of 95-LFG to replace PLG would increase total E[R.sub.PAH], but use of 92-LFG would decrease total E[R.sub.PAH]. Annual consumption rates of the three types of gasoline show that PLG decreased from 2,599 x [10.sup.6] L/year in 1994 to 944 x [10.sup.6] L/year in 1999. On the other hand, 92-LFG and 95-LFG increased from 1,321 x [10.sup.6] L/year and 3,485 x [10.sup.6] L/year in 1994 to 2,136 x [10.sup.6] L/year and 6,118 x [10.sup.6] L/year in 1999, respectively. The increase of fuel consumption for 95-LFG was more significant than for 92-LFG during the period. That the magnitude of Avg E[F.sub.PAH] for 95-LFG (i.e., 6,380 [micro]g/L fuel) was also higher than for 92-LFG (i.e., 3,800 [micro]g/L fuel) suggests that the increases of total E[R.sub.PAH] were caused mainly by increases in 95-LFG consumption during the period. Figure 1 shows the annual increasing rates for both total gasoline consumption and total E[R.sub.PAH] from 1995 to 1999 (by reference to the values obtained in 1994). The increasing rate for total E[R.sub.PAH] (36%) was higher than the corresponding increasing rate for annual gasoline consumption (24%) over the same period. Therefore, when PLG was replaced by LFG for the test gasoline engine, it might reduce lead emissions, but would increase PAH emissions, specifically when 95-LFG was used. The above result suggests that lower-octane LFG may be a more desirable substitute for PLG. However, PAH emissions from the gasoline-powered engine might not completely reflect humans' environmental exposure level. For instance, the particle size Particle size, also called grain size, refers to the diameter of individual grains of sediment, or the lithified particles in clastic rocks. The term may also be applied to other granular materials. of particle-phase PAHs expelled from the gasoline engine might be increased in the atmosphere via aggregation with other aerosols. The resultant aggregates could be removed from the atmosphere through gravitational grav·i·ta·tion n. 1. Physics a. The natural phenomenon of attraction between physical objects with mass or energy. b. The act or process of moving under the influence of this attraction. 2. precipitation precipitation, in chemistry precipitation, in chemistry, a process in which a solid is separated from a suspension, sol, or solution. In a suspension such as sand in water the solid spontaneously precipitates (settles out) on standing. , and thus might not affect human exposure levels. Gas-phase PAHs could be adsorbed and bounded by large particles, which might in turn decrease their bioavailabilities and eventually decrease the internal dose in the human body. Because these factors were not considered, the results obtained from this study might be suggestive sug·ges·tive adj. 1. a. Tending to suggest; evocative: artifacts suggestive of an ancient society. b. but should be used with caution for policy decisions. [GRAPHIC OMITTED] As shown in Table 8, the E[R.sub.BaPeq] for PLG decreased significantly from 166 kg/year in 1994 to 60 kg/year in 1999. But for 92-LFG and 95-LFG, the E[R.sub.BaPeq] increased from 19 L/year and 352 kg/year in 1994 to 31 kg/year and 618 kg/year in 1999, respectively. The amounts of total E[R.sub.BaPeq] (i.e., the sum of E[R.sub.BaPeq] values for the three types of gasoline) increased from 536 kg/year in 1994 to 709 kg/year in 1999. In addition, the increasing rates for total E[R.sub.BaPeq] were higher than the corresponding increasing rates for total gasoline consumption from 1995 to 1999 (Figure 1). The above results again suggest that the increase of total E[R.sub.BaPeq] could not be explained simply by the increase in total gasoline consumption. This was also affected by the magnitude of Avg EF E[R.sub.BaPeq] for the three types of gasoline. As shown in Table 7, the magnitudes of Avg E[F.sub.BaPeq] presented in sequence for the three types of gasoline were 95-LFG > PLG > 92-LFG (i.e., 101 [micro]g/L fuel > 63.7 [micro]g/L fuel > 14.3 [micro]g/L fuel). Therefore, the increases of total E[F.sub.BaPeq] were caused mainly by the increases of 95-LFG consumption during the period. The above results suggest the use of LFG to replace LPG LPG: see liquefied petroleum gas. 1. LPG - Linguaggio Procedure Grafiche (Italian for "Graphical Procedures Language"). dott. Gabriele Selmi. Roughly a cross between Fortran and APL, with graphical-oriented extensions and several peculiarities. in gasoline engines would significantly increase the emission of carcinogenic PAHs, particularly when 95-LFG was used instead of 92-LFG. However, the increasing rates obtained for both total E[R.sub.PAH] and total E[R.sub.BaPeq] show that the values for the former were slightly higher than the corresponding values for the latter (Figure 1). This result suggests that the use of LFG to replace LPG for the test gasoline-powered engine would produce approximately equal significance for the increase of both total E[R.sub.PAH] and total E[R.sub.BaPeq]. The results obtained from this study are applicable only for gasoline fuels with similar chemical compositions when tested against the same type of gasoline-powered engine. Both LPG and LFG found outside Taiwan might contain different chemical compositions (even the fuel with the same RON/MON range), so the PAH emissions in the engine exhaust could be different. Therefore, the results obtained in this study should not be adopted directly for policy decisions in other countries. Moreover, recent studies have indicated the PAH emissions from the gasoline-powered engine might also be affected by the types of lubricant (15) and catalytic converter catalytic converter: see internal-combustion engine. catalytic converter In automobiles, a component of emission control systems used to reduce the discharge of noxious gases from the internal-combustion engine. (16). Because other types of engine, gasoline fuel, lubricant, and catalytic converter will affect PAHs emission in the engine exhaust, further studies should be conducted to extend the generality gen·er·al·i·ty n. pl. gen·er·al·i·ties 1. The state or quality of being general. 2. An observation or principle having general application; a generalization. 3. of the above findings. Conclusions In this study, we found the three types of fuel originally contained comparable total PAH content. However, the emissions of total PAHs in exhaust gas from the test gasoline-fueled engines were different when produced under different operating conditions. The averaged emission factors (Avg E[F.sub.PAH]) for the gasoline-powered engine operated under the four test cruising speeds were 95-LFG > PLG > 92-LFG, indicating that the PAHs originally contained in the fuel did not affect the PAH emissions in the engine exhaust. We also examined the emissions of Ba[P.sub.eq] from the health-risk point of view. Again, we found that the average Ba[P.sub.eq] emission factors (Avg E[F.sub.BaPeq]) for the gasoline-powered engine operated under the four test cruising speeds also shared the same trend of 95-LFG > PLG > 92-LFG. Therefore, using 95-LFG to replace PLG would increase both Avg E[F.sub.PAH] and Avg E[F.sub.BaPeq], whereas using 92-LFG as the substitute would decrease of both amounts. By taking both emission factors and gasoline consumption rates into account, we found that both the total PAH emission rate (total E[R.sub.PAH]) and total Ba[P.sub.eq] emission rate (total E[R.sub.BaPeq]) consistently increased from 1995 to 1999. However, the increasing rates for total E[R.sub.PAH] were slightly higher than the corresponding rates for total E[R.sub.BaPeq]. Given that gasoline fuels outside Taiwan might contain different chemical compositions, PAH emissions in engine exhausts could be different. Therefore, the results obtained from this study should be used with caution for policy decisions in other countries.
Table 1. Gasoline consumption rates for PLG,
92-LFG, and 95-LFG in Taiwan, 1994-1999 ([10.sup.6]
L/year).
Year PLG 92-LFG 95-LFG Total
1994 2,599 1,321 3,485 7,405
1995 2,160 1,571 4,166 7,897
1996 1,826 1,792 4,699 8,317
1997 1,488 1,922 5,101 8,511
1998 1,219 2,036 5,681 8,936
1999 944 2,136 6,118 9,198
Data from internal statistics, Chinese Petroleum Co.
Table 2. PAH compounds and their TEFs.
PAH TEF
Naphthalene (Nap) 0.001
Acenaphthylene (AcPy) 0.001
Acenaphthene (Acp) 0.001
Fluorene (Flu) 0.001
Phenanthrene (PA) 0.001
Anthracene (Ant) 0.01
Fluoranthene (FL) 0.001
Pyrene (Pyr) 0.001
Cyclopenta[c,d]pyrene (CYC) -- (a)
Benzo[a]anthracene (BaA) 0.1
Chrysene (CHR) 0.01
Benzo[b]fluoranthene (BbF) 0.1
Benzo[k]fluoranthene (BkF) 0.1
Benzo[e]pyrene (BeP) -- (a)
Benzo[a]pyrene (BaP) 1
Perylene (PER) -- (a)
Indeno[1,2,3,-cd]pyrene (IND) 0.1
Dibenzo[a,h]anthracene (DBA) 1
Benzo[b]chrysene (BbC) -- (a)
Benzo[ghi]perylene (BghiP) 0.01
Coronene (COR) -- (a)
Data from Nisbet and Lagoy (11).
(a) No TEF has been suggested.
Table 3. Specifications for PLG, 92-LFG, and 95-LG.
Specification PLG 92-LFG 95-LFG
Product no. 13-F11095 113-F12092 113-F12095
Octane no. 95 92 95
Reid vapor pressure
(kPa at 37.8 [degrees] F) 69 69 69
Sulfur content (%wt) 0.10 0.10 0.10
Lead content (g Pb/L) 0.08 0.013 0.013
Distillation ([degrees] C)
10% 74 74 74
50% 127 127 127
90% 190 190 190
End point ([degrees] C) 225 225 225
Residue (%vol) 2 2 2
Table 4. Gasoline consumption, inlet-air flow rate, and exhaust-gas
flow rate for gasoline-powered engine operated at idling,
40 km/hr, 80 km/hr, and 110 km/hr.
Fuel consumption rate Inlet air Exhaust
(L/hr) flow gas
rate flow rate
Driving speed PLG 92-LFG 95-LFG (L/min) (L/min)
Idling 3.80 2.80 3.70 319 750
40 km/hr 4.16 3.00 4.04 474 1,130
80 km/hr 5.10 4.68 4.60 844 1,650
110 km/hr 6.54 4.96 5.86 1,100 2,250
Table 5. Mean PAH concentration and its corresponding Ba[P.sub.eq]
concentration originally contained in PLG, 92-LFG, and 95-LFG (n = 6).
PLG (mg/L) 92-LFG(mg/L)
Compound PAH Ba[P.sub.eq] PAH Ba[P.sub.eq]
Nap 11.4 0.0114 12.83 0.0128
AcPy 0.59 0.00059 0.94 0.00094
Acp 0.17 0.00017 0.30 0.0003
Flu 0.88 0.00088 1.24 0.00124
Ant 0.18 0.0018 0.32 0.0032
PA 0.38 0.00038 0.36 0.00036
FL 0.06 0.00006 0.12 0.00012
Pyr 0.01 0.00001 0.06 0.00006
CYC 0.02 -- 0.04 --
BaA 0.04 0.004 0.02 0.002
CHR 0.01 0.0001 0.02 0.0002
BbF 0.004 0.0004 0.002 0.0002
BkF 0.003 0.0003 0.01 0.001
BeP 0.002 -- 0.002 --
BaP 0.01 0.01 0.01 0.01
PER 0.01 -- 0.02 --
IND 0.37 0.037 0.31 0.031
DBA 0.02 0.02 0.04 0.04
BbC 0.10 -- 0.10 --
Bghip 0.15 0.0015 0.14 0.0014
COR 0.03 0 0.03 --
Total 13.8 0.09 16.9 0.11
95-LFG (mg/L)
Compound PAH Ba[P.sub.eq]
Nap 11.5 0.0115
AcPy 0.71 0.00071
Acp 0.24 0.00024
Flu 0.85 0.00085
Ant 0.21 0.0021
PA 0.67 0.00067
FL 0.08 0.00008
Pyr 0.04 0.00004
CYC 0.01 --
BaA 0.05 0.005
CHR 0.03 0.0003
BbF 0.002 0.0002
BkF 0.003 0.0003
BeP 0.01 --
BaP 0.007 0.007
PER 0.03 --
IND 0.25 0.025
DBA 0.04 0.04
BbC 0.05 --
Bghip 0.14 0.0014
COR 0.03 --
Total 15.0 0.10
Table 6. Mean PAH concentrations contained in fuel (n = 6) and engine
exhausts (n = 3) operated at four driving speeds for the tested engine
with PLG, 92-LFG, and 95-LFG
PLG Engine exhaust ([micro]g/[m.sup.3]
PAHs Idling 40 km/hr 80 km/hr 110 km/hr
Nap 120 75.1 61.5 102
AcPy 2.58 7.8 5.24 1.92
Acp 0.25 0.32 2.57 6.52
Flu 36.6 81.3 82.6 34.6
Ant 14.1 33.6 21.2 33.8
PA 2.82 1.35 1.42 1.27
FL 9.97 18.2 6.26 4.14
Pyr 5.22 11.3 6.32 3.58
CYC 0.67 2.83 0.99 0.93
BaA 0.55 5.13 2.50 3.53
CHR 2.61 6.43 3.21 4.41
BbF 1.01 2.94 1.63 3.04
BkF 1.08 3.34 2.07 2.91
BeP 1.09 0.72 0.55 0.54
BaP 0.81 2.20 1.29 1.72
PER 0.13 0.22 0.10 0.21
IND 1.27 5.06 1.66 6.84
DBA 0.39 0.58 0.31 0.64
BbC 0.89 1.07 0.95 1.48
Bghip 3.21 3.35 5.07 2.28
COR 0.03 0.06 0.01 0.01
Total 205 263 207 216
E[F.sub.PAH] 2,430 4,280 4,030 4,470
Avg E[F.sub.PAH] 3,800 [micro]g/L fuel
92-LFG Engine exhaust [micro]g/[m.sup.3]
PAHs Idling 40 km/hr 80 km/hr 110 km/hr
Nap 146 96.8 121 88.2
AcPy 0.65 0.59 0.51 0.68
Acp 0.42 0.39 0.55 0.86
Flu 5.42 3.59 3.48 2.62
Ant 1.26 0.79 0.96 0.95
PA 1.12 0.82 0.97 0.89
FL 1.11 0.38 0.43 1.02
Pyr 0.25 0.23 0.12 0.22
CYC 1.05 1.61 1.40 1.50
BaA 0.32 0.49 0.99 0.72
CHR 0.21 0.47 0.18 0.29
BbF 0.27 0.12 0.29 0.28
BkF 0.11 0.03 0.05 0.19
BeP 0.44 0.15 0.22 0.23
BaP 0.06 0.04 0.03 0.08
PER 1.78 0.87 1.17 2.26
IND 3.15 1.87 3.45 4.27
DBA 0.03 0.02 0.03 0.10
BbC 0.05 0.04 0.06 0.04
Bghip 0.15 0.16 0.23 0.14
COR 0.002 ND ND 0.01
Total 164 109 136 106
E[F.sub.PAH] 2,630 2,470 2,880 2,870
Avg E[F.sub.PAH] 2,710 [micro]g/L fuel
95-LFG Engine exhaust ([micro]g/[m.sup.3])
PAHs Idling 40 km/hr 80 km/hr 110 km/hr
Nap 147 95.9 87.5 97.0
AcPy 1.22 5.19 8.09 5.52
Acp 0.68 0.28 0.32 35.0
Flu 72.7 43.8 77.6 212
Ant 54.3 67.2 58.5 35.6
PA 6.72 9.52 6.85 7.97
FL 16.2 14.7 11.0 5.30
Pyr 10.6 10.8 9.32 9.99
CYC 5.86 4.6 3.44 13.8
BaA 4.45 3.71 3.21 3.53
CHR 4.57 3.62 5.04 5.49
BbF 2.04 1.49 3.13 3.14
BkF 1.96 2.19 3.75 4.06
BeP 1.19 0.62 0.76 2.12
BaP 1.62 1.48 2.73 3.23
PER 0.21 0.14 0.31 0.18
IND 1.98 1.73 5.60 5.77
DBA 0.44 0.38 0.86 1.37
BbC 0.40 0.9 1.38 1.19
Bghip 2.39 5.11 2.75 5.36
COR 0.02 0.04 0.01 0.03
Total 337 274 292 458
E[F.sub.PAH] 4,090 4,590 6,290 10,500
Avg E[F.sub.PAH] 6,380 [micro]g/L fuel
Table 7. Mean Ba[P.sub.eq] concentrations ([micro]g/N[m.sup.3])
contained in engine exhausts (n = 3) operated at four driving
speeds for the tested engine using the fuel of PLG,
92-LFG, and 95-LFG.
PLG Engine exhaust ([micro]g/N[m.sup.3]
PAHs Idling 40 km/hr 80 km/hr 110 km/hr
Nap 0.120 0.0751 0.0615 0.102
AcPy 0.00258 0.0078 0.00524 0.00192
Acp 0.00025 0.00032 0.00257 0.00652
Flu 0.0366 0.0813 0.0826 0.0346
Ant 0.141 0.336 0.212 0.338
PA 0.00282 0.00135 0.00142 0.00127
FL 0.00997 0.0182 0.00626 0.00414
Pyr 0.00522 0.0113 0.00632 0.00358
CYC -- -- -- --
BaA 0.055 0.513 0.250 0.353
CHR 0.0261 0.0643 0.0321 0.0441
BbF 0.101 0.294 0.163 0.304
BkF 0.108 0.334 0.207 0.291
BeP -- -- -- --
BaP 0.810 2.20 1.29 1.72
PER -- -- -- --
IND 0.127 0.506 0.166 0.684
DBA 0.390 0.58 0.31 0.64
BbC -- -- -- --
Bghip 0.0321 0.0335 0.0507 0.0228
COR -- -- -- --
Total 1.97 5.06 2.85 4.55
E[F.sub.BaPeq] 23.3 82.4 55.3 93.9
Avg E[F.sub.BaPeq] 63.7 [micro]g/L fuel
92-LFG Engine exhaust ([micro]g/[m.sup.3])
PAHs Idling 40 km/hr 80 km/hr 110 km/hr
Nap 0.146 0.0968 0.121 0.0882
AcPy 0.00065 0.00059 0.00051 0.00068
Acp 0.00042 0.00039 0.00055 0.00086
Flu 0.00542 0.00359 0.00348 0.00262
Ant 0.0126 0.0079 0.0096 0.0095
PA 0.00112 0.00082 0.00097 0.00089
FL 0.00111 0.00038 0.00043 0.00102
Pyr 0.00025 0.00023 0.00012 0.00022
CYC -- -- -- --
BaA 0.032 0.049 0.099 0.072
CHR 0.0021 0.0047 0.0018 0.0029
BbF 0.027 0.012 0.029 0.028
BkF 0.011 0.003 0.005 0.019
BeP -- -- -- --
BaP 0.06 0.04 0.03 0.08
PER -- -- -- --
IND 0.315 0.187 0.345 0.427
DBA 0.03 0.02 0.03 0.1
BbC -- -- -- --
Bghip 0.0015 0.0016 0.0023 0.0014
COR -- -- -- --
Total 0.65 0.43 0.68 0.83
E[F.sub.BaPeq] 10.4 9.67 14.4 22.7
Avg E[F.sub.BaPeq] 14.3 [micro]g/L fuel
95-LFG Engine exhaust ([micro]g/N[m.sup.3]
PAHs Idling 40 km/hr 80 km/hr 110 km/hr
Nap 0.147 0.0959 0.0875 0.097
AcPy 0.00122 0.00519 0.00809 0.00552
Acp 0.00068 0.00028 0.00032 0.035
Flu 0.0727 0.0438 0.0776 0.212
Ant 0.543 0.672 0.585 0.356
PA 0.00672 0.00952 0.00685 0.00797
FL 0.0162 0.0147 0.011 0.0053
Pyr 0.0106 0.0108 0.00932 0.00999
CYC -- -- -- --
BaA 0.445 0.371 0.321 0.353
CHR 0.0457 0.0392 0.0504 0.549
BbF 0.204 0.149 0.313 0.314
BkF 0.196 0.214 0.375 0.406
BeP -- -- -- --
BaP 1.62 1.48 2.73 3.23
PER -- -- -- --
IND 0.198 0.173 0.56 0.577
DBA 0.44 0.38 0.86 1.37
BbC -- -- -- --
Bghip 0.0239 0.0511 0.0275 0.0536
COR -- -- -- --
Total 3.97 3.71 6.02 7.09
E[F.sub.BaPeq] 48.3 62.3 130 163
Avg E[F.sub.BaPeq] 101 [micro]g/L fuel
Table 8. Emission rates of total PAHs and total Ba[P.sub.eq] for PLG,
92-LFG, and 95-LFG in a gasoline-powered engine in Taiwan, 1994-1999
(kg/year).
PLG 92-LFG
Year E[R.sub.PAH] E[R.sub.BaPeq] E[R.sub.PAH] E[R.sub.BaPeq]
1994 9,876 166 3,580 19
1995 8,208 138 4,257 22
1996 6,939 116 4,856 26
1997 5,654 95 5,209 27
1998 4,632 78 5,518 29
1999 3,587 60 5,789 31
95-LFG Total
Year E[R.sub.PAH] E[R.sub.BaPeq] E[R.sub.PAH] E[R.sub.BaPeq]
1994 22,234 352 35,690 536
1995 26,579 421 39,044 581
1996 29,980 475 41,775 617
1997 32,544 515 43,407 637
1998 36,245 574 46,395 681
1999 39,033 618 48,409 709
REFERENCES AND NOTES (1.) Pedersen PS, Ingwersen J, Nielsen T, Larson E. Effects of fuel, lubricant, and engine operating parameters on the emission of polycyclic aromatic hydrocarbons. Environ Sci Tech 14:71-79 (1980). (2.) Bjorseth A, Ramdahl T. Source and emissions of PAH. In: Handbook of Polycyclic Aromatic Hydrocarbons. New York New York, state, United States New York, Middle Atlantic state of the United States. It is bordered by Vermont, Massachusetts, Connecticut, and the Atlantic Ocean (E), New Jersey and Pennsylvania (S), Lakes Erie and Ontario and the Canadian province of :Marcel Dekker Marcel Dekker is a well-known encyclopedia publishing company with editorial boards found in New York, New York. They are part of the Taylor and Francis publishing group. Initially a textbook publisher, they went to encyclopedia publishing in the late 1990's. Inc., 1985;1-2. (3.) Benner BA, Gordon GE, Wise SA. Mobile sources of atmospheric polycyclic aromatic hydrocarbon: a roadway tunnel study. Environ Sci Technol 23:1269-1277 (1989). (4.) Baek SO, Field RA, Goldstone gold·stone n. An aventurine with gold-colored inclusions. Noun 1. goldstone - aventurine spangled densely with fine gold-colored particles ME, Kirk PW, Lester JN, Perry R. A review of atmospheric polycyclic aromatic hydrocarbons: sources, fate and behavior. Water Air Soil Pollut 60:273-300 (1991). (5.) Handa T, Yamamura T, Kato Y, Saito S Saitō (usually 斉藤 or 斎藤, but other forms are common) is the seventeenth most common Japanese surname. [1] (.XLS file) People named Saitō include:
pol·y·nu·cle·ar or pol·y·nu·cle·ate or pol·y·nu·cle·at·ed adj. Multinuclear. aromatic hydrocarbon emission from automobiles. Environ Sci Technol 113:1079-1081 (1979). (6.) Westerholm R, Alsberg TE, Frommelin AB, Strandell ME, Rannug U, Winquist L, Grigoriadis V, Egeback K. Effect of fuel polycyclic aromatic hydrocarbon content on the emission of polycyclic aromatic hydrocarbons and other mutagenic mutagenic inducing genetic mutation. substances from a gasoline-fueled automobile. Environ Sci Technol 22:925-930 (1988). (7.) Wallington TJ, Andino LM, Potts AR, Rudy SJ, Sigle WO, Zhang Z, Kurylo MJ, Hule RE. Atmosphere chemistry of automotive fuel additives: diisopropyl ether Diisopropyl ether is secondary ether that is used as a solvent. It is a colorless liquid that is slightly soluble in water, but miscible with most organic solvents. It is also used as an oxygenate gasoline additive. . Environ Sci Technol 27:98-104 (1993). (8.) IARC. Overall evaluations of carcinogenicity carcinogenicity /car·ci·no·ge·nic·i·ty/ (kahr?si-no-je-nis´i-te) the ability or tendency to produce cancer. carcinogenicity the ability or tendency to produce cancer. : an updating of IARC Monographs volumes 1 to 42. IARC Monogr Eval Carcinog Risks Hum hum (hum) a low, steady, prolonged sound. venous hum a continuous blowing, singing, or humming murmur heard on auscultation over the right jugular vein in the sitting or erect position; it is Suppl 7:1-440 (1987). (9.) Chu M, Chen C. Evaluation and estimation of potential carcinogenic risks of polynuclear aromatic hydrocarbons. Presented et the Symposium on Polycyclic Aromatic Hydrocarbons in the Workplace, Pacific Rim Pacific Rim, term used to describe the nations bordering the Pacific Ocean and the island countries situated in it. In the post–World War II era, the Pacific Rim has become an increasingly important and interconnected economic region. Risk Conference, Honolulu, HI, 4-7 December 1984. (10.) Thorslund T, Farrer D. Development of relative potency estimated for PAHs end hydrocarbon hydrocarbon (hī'drōkär`bən), any organic compound composed solely of the elements hydrogen and carbon. The hydrocarbons differ both in the total number of carbon and hydrogen atoms in their molecules and in the proportion of hydrogen combustion product fractions compared to benzo(a)pyrene and their use in carcinogenic risk assessments. Washington DC:US. Environmental Protection Administration, 1991. (11.) Nisbet C, LaGoy P. Toxic equivalency equivalency the combining power of an electrolyte. See also equivalent. factors (TEFs) for polycyclic aromatic hydrocarbons (PAHs). Regul Toxicol Pharmocol 16:290-300 (1992). (12.) Petry T, Schmid P, Schlatter C. The use of toxic equivalency factors in assessing occupational and environmental health risk associated with exposure to airborne mixtures of polycyclic aromatic hydrocarbons (PAHs). Chemosphere chemosphere: see atmosphere. 32:639-648 (1996). (13.) Atal A, Levendis Y, Carlson J, Dunayevskiy Y, Vouros P. On the survivability and pyrosynthesis of PAH during combustion of pulverized pul·ver·ize v. pul·ver·ized, pul·ver·iz·ing, pul·ver·iz·es v.tr. 1. To pound, crush, or grind to a powder or dust. 2. To demolish. v.intr. coal and tire crumb. Combust com·bust v. com·bust·ed, com·bust·ing, com·busts v.intr. 1. a. To catch fire; burst into flame: The fire started when a pile of oily rags spontaneously combusted. Flame 110:462-478 (1997). (14.) Catherine AP, Christopher DK, Derick GB. Long-term composition dynamics of PAH-containing NAPLs and implications for risk assessment. Environ Sci Technol 33:4499-4507 (1999). (15.) Kaiser EW, Siegl WO, Cotton DF, Andersen RW. Effect of fuel structure on emission from a spark-ignited engine: 3. Olefinic fuels. Environ Sci Technol 27:1440-1447 (1993). (16.) Karvounis E, Assanis DN. The effect of inlet distribution on catalytic cat·a·lyt·ic adj. Of, involving, or acting as a catalyst: "Deregulation's catalytic power . . . is still reshaping the banking, communications, and transportation industries" Ellyn E. conversion efficiency. Int J Heal Mass Transfer 36:1495-1504 (1983). Hsiao-Hsuan Mi, (1) Wen-Jhy Lee, (1) Perng-Jy Tsai, (2) and Chung-Ban Chen (3) (1) Department of Environmental Engineering, National Cheng Kung University National Cheng Kung University (Traditional Chinese: 國立成功大學; Simplified Chinese: 国立成功大学 , Tainan, Taiwan; (2) Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan,Taiwan; (3) Heavy Duty Diesel Engine Emission Group, Refining refining, any of various processes for separating impurities from crude or semifinished materials. It includes the finer processes of metallurgy, the fractional distillation of petroleum into its commercial products, and the purifying of cane, beet, and maple sugar and Manufacturing Center, Chinese Petroleum Corporation, Chia-Yi, Taiwan Address correspondence to P.-J. Tsai, Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, 138 Sheng-Li Road, Tainan 70428, Taiwan. Telephone: +886-6-2353535/5806. Fax: +886-6-2752484. E-mail: pjtsai@mail.ncku.edu.tw Received 9 January 2001: accepted 25 April 2001. |
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