Environ. Sci. Technol. 1990, 2 4 , 908-912
chlorination stage conditions a-terpineol reacts with chlorine (as ClJ to give a chloronium ion species, which can be quenched (neutralized) by the attack of a water molecule to afford a chlorohydrin adduct. The introduction of the second chlorine atom (typically to give the CH&1 group) may proceed via dehydration of the initial chlorohydrin to afford a chloroalkene, which may then react in a like manner. To our knowledge, previous reports of chlorinated monoterpenes in bleaching effluents have been confined to the chlorinated cymenes and cymen-8-01s (1). Small amounts of these compounds were found in the bleaching effluents of the mill under study. Another group of chlorinated monoterpenes of unknown structure and with molecular masses and formulas different from those reported here have recently been reported (11). Therefore, it would seem that these chlorinated monoterpene hydrocarbons and alcohols are novel. Conclusions
Our work has identified 14 previously unreported compounds present in chlorination stage bleaching effluents from a kraft pulp and paper mill operating on the softwood P. radiata. The compounds are chlorinated and hydroxylated derivatives of the P. radiata monoterpenes, a-pinene, 0-pinene, borneol, 4-terpineol, and a-terpineol. These compounds arise from the chlorination of monoterpenes entering the bleach plant as a result of incomplete removal of wood extractives during pulping in the mill’s continuous kraft digester. These chlorinated monoterpenes are the major low molecular weight, chlorinated, organic compounds discharged in the mill’s bleach plant wastewaters. Studies are underway to determine their toxicity, mutagenicity, and fate in the mill’s effluent treatment system.
Acknowledgments
We thank Mr. T. K. McGhie of the Ruakura Agricultural Centre, Hamilton, for providing high-resolution GC/MS data and Dr. J. Coddington of University of Auckland, Auckland, for providing 400-MHz NMR data. Literature Cited (1) Kringstad, K. P.; Lindstrom, K. Environ. Sei. Technol. 1984, 18, 236A. (2) D. McLeay and Associates Aquatic Toxicity of Pulp and Paper Mill Effluent: A Review. Report EPS 4/PF/1; Environment Canada, 1987. (3) Stuthridge, T. R. MSc. Thesis, University of Waikato, 1987. (4) Parlar, H.; Nitz, S.; Gab, S.; Korte, F. J.Agric. Food Chem. 1977, 25, 68. ( 5 ) Swigar, A. A.; Silverstein, R. A. Monoterpenes; Aldrich Chemical Co. Inc.: Milwaukee, WI, 1981. (6) Breitmaier, E. 13CN M R Spectroscopy, Methods and Applications in Organic Chemistry, 2nd ed.; Verlag Chemie: Weinhein, 1978; p 136. ( 7 ) Carman, R. M.; Venzke, B. N. A w t . J. Chem. 1973,26,2235. (8) Kopperman, H. L.; Hallcher, R. C., Sr.; Riehl, A.; Carlson, R. M.; Caple, R. Tetrahedron 1976,32, 1621. (9) Goessens, J. Recovery of Turpentine from No. 1 and No. 2 Pulp Digesters. Unpublished report, N.Z.F.P. Pulp and Paper Ltd, Tokoroa, New Zealand, 1984. (10) Campin, D. C. N.Z.F.P. Pulp and Paper Ltd, Tokoroa, New Zealand, personal communication, 1990. (11) Carlberg, G. E.; Johnsen, S.; Landmark, L. H.; Bengtsson, B.-E.; Bergstrom, B.; Skramstad, J.; Stroflor, H. Water Sei. Technol. 1988, 20, 37. Received for review October 24, 1989. Accepted February 21, 1990. The financial support of this project by Technology Division, N.Z.F.P. Pulp and Paper Ltd is gratefully acknowledged.
Total Particle, Sulfate, and Acidic Aerosol Emissions from Kerosene Space Heaters Brian P. Leaderer’ and Patricia M. Boone John B. Pierce Foundation Laboratory, Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut
S. Katharine Hammond Department of Family and Community Medicine, University of Massachusetts Medical School, Worcester, Massachusetts
Chamber studies were conducted on four unvented kerosene space heaters to assess emissions of total particle, sulfate, and acidic aerosol. The heaters tested represented four burner designs currently in use by the public. Kerosene space heaters are a potential source of fine particles (52.5-pm diameter), sulfate, and acidic aerosol indoors. Fine particle concentrations in homes in which the heaters are used may be increased in excess of 20 pg/m3 over background levels. Sulfate and acidic aerosol levels in such homes could exceed average and peak outdoor concentrations. Maltuned heaters could produce exceptionally high levels of all air contaminants measured. Introduction
Unvented kerosene space heaters have become a popular low-cost method to provide supplementary heat in resi908
Environ. Sci. Technol., Vol. 24, No. 6, 1990
dences. The US. Consumer Product Safety Commission (USCPSC) estimates that 17 million heaters have been sold and that current sales are 1 million per year (1). The number of heaters currently in use is not known. The results of previous environmental chamber and field studies indicate that these heaters may produce indoor concentrations of carbon monoxide (CO), nitrogen oxides (NO,), sulfur dioxide (SO,), and carbon dioxide (CO,) in excess of levels specified in a number of health guidelines or standards (2-5). Little, however, is known about the particle and organic emissions from these heaters. As part of a research program to characterize air contaminant emissions from indoor combustion sources we conducted a series of environmental chamber studies to assess the chemical composition and the level of volatile and semivolatile organics and particles emitted by kerosene space heaters. Here we report data on particle, sulfate,
00 13.~936X/90/0924-0908$02.50/0 0 1990 American Chemical Society
and acidic aerosol emissions for four of the heaters evaluated and discuss the implications of the results with respect to the potential exposure of residents.
Methods Four portable unvented kerosene space heaters were evaluated in the study. These represent the range of burner designs currently in use. Two of the heaters were of single-burner design [a 12500 Btu/h rated radiant heater (R) and a 17 100 Btu/h rated convective heater (C)] and two of the heaters were of double-burner design [a 9400 Btu/h rated convective/radiant heater (C/R) and a 12600 Btu/h rated two-stage radiant heater (R/R)]. The R/R heater had a catalyst over the burner. The R, C/R, and R/R heaters tested were obtained from the USCPSC, but the C heater was personally owned. The R, R/R, and C heaters were of uncertain age and maintenance condition, but the C/R heater was new. The R/R heater showed some evidence of considerable use and may have been maltuned. The same kerosene (obtained from a retailer and stored in a 55-gal drum) was burned in all experiments. Analysis of the kerosene showed a sulfur content of 0.039%, which is just below the regulated level of 0.04% for "K-1" grade kerosene (6). The heaters were operated in a 1200-ft3 (34-m3) aluminum-lined chamber (7) equipped with an efficient ventilation system, ensuring rapid mixing of outdoor air with the air contaminants generated in the chamber by the kerosene heaters. Air entered the chamber through a plenum beneath a perforated floor and exited through four vents in the ceiling. The volume flow (recirculation rate) was set at 1900 ft3/min (950 L/s) or 95 air changes/h (ach). Fresh air (ventilation) was mixed with recirculated air at a rate of 28 ft3/min (14 L/s) or 1.4 ach. The ventilation rate was calibrated by introducing a predetermined concentration of COPinto the unoccupied chamber and then measuring the decay of the concentration with an infrared C02 analyzer. The chamber had excellent control of dry-bulb temperature (f0.1 "C). During heater operation the chamber temperature was kept at 28 "C by passing the recirculation air in the chamber over a cooling coil. The cooling coil was maintained at a level several degrees above the dew point of the air in the chamber during heater operation to prevent scavenging of combustion gases by condensing water vapor. The heaters were fueled outside the laboratory prior to each experiment and placed in the chamber on a Potter scale, which had a sensitivity of f0.5 g. Before the heater was lit, background measurements of continuously monitored gases (CO, COP,NO,, SOz, and non-methane hydrocarbons), particle size distributions from 0.03 to 10.0 pm diameter (electric mobility aerosol analyzer and optical aerosol analyzer), chamber temperature, and dew point were taken. After background concentrations were recorded, the heater was started and operated for 12 h at the flame setting recommended by the manufacturer as being the most efficient. These flame settings were determined visually in accordance with the user's manual. During the operating time of the heater, particle mass was collected at 18 locations throughout the chamber on 37-mm Teflon-coated glass fiber filters (Pallflex TX40H120WW) with medium-flow pumps sampling at a calibrated rate of 3.00 f 0.05 L/min. Collected particle mass was determined gravimetrically. Samples of aerosol for strong acid, ammonium, nitrate, and sulfate analysis were collected on two acid-treated quartz filters prepared and analyzed at Brookhaven National Laboratory (8). These filters were
Table I. Aerosol Chemical Composition concentrations, bg/m3 kerosene heater typeb total (rated Btu/h) mass chamber backgrd conv (17 100) conv/rad (9 400) rad (12 500) rad/rad (12600)
NH4+ H+O
S042- NO;
4.1 11.1 114.0 68.5 72.5 32.6 109.1 58.0 1126.0 692.7
0.5 1.5 0.7 0.8 1.1
1.3 23.6 12.0 19.6 46.3
ND' 17.2 1.4 16.9 74.6
'H+calculated as H2S04. conv, convective; rad, radiant. ND, not detectable. combined prior to analysis for strong acid by Gran's titration (9),ammonium by indophenol colorimetry (IO),and nitrate and sulfate by ion chromatography (11). Measurements of the continuously monitored gases, particle size distribution, air temperature, dew point, and fuel consumption were recorded throughout the 12-h operation period of the heaters and, with the exception of fuel consumption, continued for 1h after heater shutoff. Deposition rates for the air contaminants on chamber surfaces were determined by monitoring the decay of gas and particle concentrations after heater shutoff and comparing them to the decrease in C02 concentration (ventilation rate). The chamber background experiment was conducted in the same manner (12-h run) as the kerosene heater experiments, only without a heater in the chamber.
Results Particle size distribution measurements indicated that the particles produced by the heaters were less than 2.5-pm diameter. The measured chamber concentrations of total particle mass, sulfate, nitrate, strong acid, and ammonium for the four heaters and the chamber background are summarized in Table I. Background chamber concentrations of total particle mass, sulfate, ammonium, and acidic aerosol were
