3
New Smoke Formulations
YELLOW-SMOKE FORMULATION
Composition
THE MAJOR dye component of the new yellow-smoke formulation is 2(2-quinolyl)-1,3-indandione (QID) (42% of total components). This dye is also called solvent yellow 33. An insoluble residue constitutes approximately 3.7% of the formulation. In the new M18 grenades designed to replace those containing the old smoke formulation, sugar is used as the fuel instead of sulfur, and magnesium carbonate is used as a coolant instead of sodium bicarbonate.
Combustion Products
Buchanan and Ma (1988) characterized the combustion products produced by the new M18 grenades containing the new yellow-smoke formulation. The grenades were detonated inside canvas tents, and samples of the vapors and particles generated by the grenade were collected. Approximately 5% of solvent yellow 33 was converted to oxidized products tentatively identified as quinolylnapthalone and isomers of quinoylnapthoquinone. The insoluble residue constituted 5.0% to 9.9% of the combustion product, and the mass median aerodynamic diameters were 0.85 micrometer (µm) at 3 min and 1.80 µm at 30 min.
Additional information on the combustion products of the new yellow-smoke formulation is presented in Chapter 1.
Toxicokinetics
No studies have been conducted on the toxicokinetics of the new yellow-smoke formulation or its combustion products. However, toxicokinetics studies have been conducted on pure solvent yellow 33 dye. Those are summarized in Appendix C. Extrapolating the results of toxicokinetics studies conducted in animals suggests that solvent yellow 33 will be rapidly absorbed from the respiratory tract after inhalation in humans, and extensively metabolized, with metabolites excreted primarily in bile and eliminated in feces. No tissues appear to be storage depots for significant quantities of solvent yellow 33.
Toxicity of the Smoke Formulation and Its Combustion Products
This section reviews the toxicity of the new yellow-smoke formulation and its combustion products. The toxicity of the component dye is evaluated in Appendix C.
No epidemiological studies have been conducted on military workers or others exposed to the smoke formulation or its combustion products. Likewise, no toxicity studies have been conducted in experimental animals. However, one study was conducted on the inhalation toxicity of the combustion products of a smoke formulation composed of solvent yellow 33 and disperse orange 11 (Marrs et al. 1988), and another was conducted on the inhalation toxicity of the combustion products of a smoke formulation composed of solvent green 3, solvent yellow 33, and disperse red 9 (Marrs et al. 1984). Because those smoke formulations contain solvent yellow 33, the results have some value in assessing the toxicity of the combustion products. The study on solvent yellow 33 and disperse orange 11 is discussed here. The study on the toxicity of the combustion products of the smoke formulation containing the three dyes is discussed in Chapter 2.
In the Marrs et al. (1988) study, smoke was generated by ignition of a pyrotechnic composition containing solvent yellow 33 and disperse
orange 11. Female rats, mice, and guinea pigs were exposed to freshly generated smoke for 1 hr per day, 5 days per week until they had received 200 exposures. Guinea pigs in the highest-dose group received only 75 exposures. Thick washers of the smoke components were ignited on electrically heated wire, and the resultant colored smoke was mixed using high velocity jets in a static 10-cubic-meter (m3) chamber. Concentrations in the chamber were varied by igniting different numbers of washers. Groups of each species were exposed together, starting with exposure of the controls to air and ending with the exposure of the highest-dose group. As the concentration declined during the exposure of each test group, fresh washers of the pyrotechnic composition were ignited to maintain the smoke concentration. During each exposure, samples of the smoke were collected on glass-fiber filters for determination of concentration. Particle size was determined using an Anderson particle sizer. All animals alive at the end of the exposures were observed until they died or until the end of a 6-month observation period (17 months after the start of exposure).
Mean exposure concentrations were 0.1 grams per cubic meter (g/m3), 0.3 g/m3, or 1.0 g/m3. The mass median diameter of the smoke was 0.95, 1.55, and 1.10 µm for the three dose groups, respectively. For rats, there was a significant increase in total mortality in the highest-dose group compared with controls over the total exposure period. For guinea pigs, a large number of deaths occurred in the highest-dose group within a very short period in the fourth month of the study, and thus the high-dose guinea pigs were not exposed further. An increased number of deaths during the exposure period occurred in mice of the high-dose group compared with the controls. For mice that survived to the end of the study, an increased incidence of macrophage infiltration and an increased incidence of dilated mucous glands in the trachea were observed in the high-dose group. In rats, an increased incidence in macrophages with granules was seen in the middle-and high-dose groups. Guinea pigs had a statistically significant increase in the presence of excess macrophages and peribronchial lymphocyte infiltration.
Marrs et al. (1988) noted that the large number of deaths observed in the high-dose group of guinea pigs was not unprecedented, because a similar phenomenon was observed in a previous inhalation study in which guinea pigs were exposed to the combustion products of a brown smoke-formulation containing a mixture of three dyes: solvent green 3, solvent yellow 33, and disperse red 9 (Marrs et al. 1984; reviewed in
Chapter 2). The authors commented that the lethality might be a reflection of the peculiar sensitivity of guinea pigs to the stress associated with inhalation of particles and suggested that the cause of death was due to bronchial spasms. However, solvent yellow 33 was a component of both the brown-smoke and the yellow-orange-smoke formulations. Thus, its role in the hypersensitivity of the guinea pigs to the inhaled combustion products cannot be discounted. In some cases, guinea pigs have been shown to be an appropriate animal model for study of human hypersensitivity to inhaled materials (Mauderly 1984).
Marrs et al. (1988) suggested that the combustion products of the yellow-orange-smoke formulation were clearly toxic to all test groups of the three species studied, because the relative body weights decreased during the exposure period. However, organ-specific toxicity appeared to be confined to the respiratory tract. In the surviving animals, a noteworthy and significant difference from the previously tested combustion products of the brown-smoke formulation was the absence of retained dye in the lungs of any species and the absence of sheets of packed macrophages. Those two observations were previously reported in rats exposed to the combustion products of the brown-smoke formulation containing three dyes (Marrs et al. 1984).
Marrs et al. (1988) concluded that the findings in the respiratory tract of the animals exposed to the combustion products of both the yellow-orange-smoke and the brown-smoke formulations represented the less specific effects of smoke toxicity rather than the effects of the dye components. They suggested that their findings might be common to all military smokes and were probably caused by the nondye constituents. Their findings included lymphocyte infiltration into the larynx and trachea in the mice and guinea pigs and dilated mucous glands in the trachea of mice and rats. The authors concluded that the findings could be explained on the basis of previous studies of the products of reaction between potassium chlorate and lactose, the main components of the resulting reaction being carbon dioxide, water, and potassium chloride (Marrs et al. 1988).
Toxicity of Component Dyes
The primary dye component of the new yellow-smoke formulation is solvent yellow 33, a demonstrated human contact allergen (reviewed in
Appendix C). Although most case reports and controlled studies have focused on dermal contact sensitivity, the sensitizing potential of inhaled solvent yellow 33 cannot be discounted. No studies in the appropriate animal models have been conducted to explore the potential for respiratory-tract sensitization after exposure to inhaled solvent yellow 33 particles.
GREEN-SMOKE FORMULATION
Composition
The major dye components of new green-smoke formulation are 1,4-dip-toluidino-9,10-anthraquinone (PTA) (29.4% of total components) and solvent yellow 33 (12.6%). PTA is also called solvent green 3. In the new M18 grenades, sugar is used as the fuel instead of sulfur, and magnesium carbonate is used as a coolant instead of sodium bicarbonate.
Combustion Products
Buchanan and Ma (1988) characterized the combustion products produced by new M18 grenades containing new green-smoke formulation. The grenades were detonated inside canvas tents, and samples of the vapor and particles generated by the grenade were collected. A small fraction (less than 1%) of solvent green 3 was altered during the combustion process, and solvent yellow 33 remained relatively unchanged upon combustion of the smoke formulation. Additional information on the combustion products of the new green-smoke formulation is presented in Chapter 1.
Toxicokinetics
No studies have been conducted on the toxicokinetics of the combustion products of the new green-smoke formulation. However, a toxicokinetics study was conducted on a mixture of solvent green 3 and solvent yellow 33 (Medinsky et al. 1986). Rats were exposed by inhalation to aerosols of a mixture of solvent green 3 and solvent yellow 33 containing trace
amounts of 14C-QID. The mass median aerodynamic diameter of the particles was 2.6 µm and the inhaled concentrations of solvent yellow 33 and solvent green 3 were 0.09 g/m3 and 0.2 g/m3, respectively. The ratio of yellow dye to total dye was 0.38 by the weight, resulting in approximately equal molar quantities of each dye. The toxicokinetics of solvent yellow 33 in the solvent green 3 and solvent yellow 33 mixture were very similar to those observed when solvent yellow 33 was inhaled as a pure chemical (reviewed in Appendix C). Solvent yellow 33 was rapidly cleared from the lungs into the blood, rapidly metabolized, and excreted in the bile. Most of the solvent yellow 33 metabolites were eliminated in the feces. No tissues appeared to store significant quantities of solvent yellow 33 or its metabolites. In contrast, solvent green 3 was retained in the lungs during the 70-hr post-exposure period with an estimated minimum half-life of 22 days for clearance. Solvent green 3 was not detected in other tissues during that period. Increased retention of solvent green 3 is consistent with that reported by other investigators (reviewed in Appendix D).
Toxicity of the Smoke Formulation and Its Combustion Products
This section reviews the toxicity of the new green-smoke formulation and its combustion products. The toxicity of the component dyes is evaluated in Appendixes C and D.
No epidemiological studies have been conducted on military workers or others exposed to the smoke formulation or its combustion products. Likewise, no toxicity studies have been conducted in experimental animals. However, the combustion products of a smoke formulation of solvent yellow 33 and disperse orange 11 (reviewed in the section on the new yellow-smoke formulation in this chapter) and a brown-smoke formulation composed of solvent green 3, solvent yellow 33, and disperse red 9 (reviewed in Chapter 2) were investigated. Because both smoke formulations contained solvent yellow 33, and the brown-smoke formulation also contained solvent green 3, the results have some value in assessing the toxicity of the combustion products of the new green-smoke formulation.
In both studies, organ-specific toxicity appeared to be confined to the respiratory tract. In the opinion of Marrs et al. (1988) two noteworthy
and significant differences between the two studies were the absence of retained dye in the lungs of surviving animals and the absence of sheets of packed macrophages in the study using the yellow-orange-smoke formulation and the observation of those effects in the study using the brown-smoke formulation. Toxicokinetics studies by Medinsky et al. (1986) found that solvent green 3 is retained in the lungs of animals following inhalation suggesting that the differences in the respiratory effects of the two combustion products might be due to the presence of solvent green 3 in the brown-smoke formulation.
Inhalation studies have also been conducted on a mixture of solvent yellow 33 and solvent green 3 aerosols. Sun et al. (1987) conducted 4-week and a 13-week inhalation toxicity studies of a 70:30 mixture of solvent green 3 and solvent yellow 33 in rats. The solvent yellow 33 cleared the lungs rapidly, and most of the pulmonary toxicity resulting from the exposures was attributed to the solvent green 3 which remained in the lungs with a calculated half-life of 280 days based on clearance observed during the 30-day post-exposure period. The mixture was not highly toxic, but at the highest exposure concentration (0.2 g/m3 for the 4-week exposure and 0.1 g/m3 for the 13-week exposure), the rats had a mild pulmonary inflammation, slight type-II cell hyperplasia, and an accumulation of vacuolated alveolar macrophages in the lungs. No other organs were affected. No effects were observed at the two lower exposure concentrations (0.01 and 0.05 g/m3 for the 4-week exposure and 0.001 and 0.01 g/m 3 for the 13-week exposure).
Toxicity of Component Dyes
The major dye component of the new green-smoke formulation is solvent green 3, which is relatively nontoxic when delivered orally or dermally to animals. Inhaled solvent green 3 is insoluble in the lungs and accumulates there when inhaled (Sun et al. 1987). The accumulation results in an inflammatory response in the lungs. The other component in the new green-smoke formulation is solvent yellow 33. Solvent yellow 33 is a demonstrated human contact allergen (reviewed in Appendix C). Even though most case reports and controlled studies of solvent yellow 33 have focused on dermal contact sensitivity, the sensitizing potential of inhaled solvent yellow 33 cannot be discounted. No studies in the appropriate animal models have been conducted to explore the potential for
respiratory-tract sensitization after exposure to inhaled solvent yellow 33 particles.
RED-SMOKE FORMULATION
Composition
The major dye components of new red-smoke formulation are α-methoxybenzenazo-β-naphthol (MBN) (34.2% of total components) and 1,4-diamino-2-methoxyanthraquionone (DMA) (6.8%). MBN is also called solvent red 1 and DMA is called disperse red 11. In the new M18 grenades, sugar is used as fuel instead of sulfur, and magnesium carbonate is used as a coolant instead of sodium bicarbonate. Additional information on the combustion products of the new red-smoke formulation is presented in Chapter 1.
Combustion Products
Buchanan and Ma (1988) characterized the combustion products produced by the new M18 grenades containing new red-smoke formulation. The grenades were detonated inside canvas tents, and samples of the vapor and particles generated by the grenade were collected. A small fraction of disperse red 11 (approximately 3%) was converted during combustion (possibly to 2-methoxyaniline and 2-naphthol), and solvent red 1 remained relatively unchanged during combustion of the new red-smoke formulation.
Toxicokinetics
No studies have been conducted on the toxicokinetics of the combustion products of the new red-smoke formulation or on solvent red 1, one of the smoke components. However, one study on the retention of disperse red 11 demonstrated that, after instillation, the dye is rapidly cleared from the lungs into the blood of rats, only 3.5% of the initial dose being retained in the lungs after 24 hr (Henderson et al. 1988).
Toxicity of the Smoke Formulation and Its Combustion Products
This section reviews the toxicity of the new red-smoke formulation and its combustion products. The toxicity of the component dyes is evaluated in Appendixes E and G.
No epidemiological studies have been conducted on military workers or others exposed to the smoke formulation or its combustion products. Likewise, no toxicity studies have been conducted using the smoke formulation or its combustion products in experimental animals. Any assessment of the potential health effects following inhalation exposure to these combustion products must be made from studies conducted with either the pure individual dye components or mixtures of the dyes.
A minimal number of studies have been conducted with mixtures of solvent red 1 and disperse red 11 (Table 3-1). Although the studies do not mimic the atmosphere to which a soldier might be exposed during training exercises using the deployed smokes, they can provide some indication of the potential synergistic effects between the two dyes. Acute toxicity studies demonstrated low toxicity after either oral or dermal exposure to the dye mixture (Table 3-1). Acute studies of either eye or dermal irritation showed the red-dye mixture to be nonirritating when applied to the skin but irritating in ocular studies (Smith et al. 1986). Hypersensitivity studies with the red-dye mixture showed no pulmonary or contact hypersensitivity in mice (Sailstad et al. 1994). One mutagenicity study conducted in a bacterial assay system (Ames test) with the red-dye mixture was negative (Brooks et al. 1989).
Inhalation studies conducted after either acute or repeated exposures to the aerosolized red-dye mixture showed nasal and lung lesions (Lundy and Eaton 1994). Only minimal details of the results of those studies have been reported (Table 3-1); therefore, it is not possible to evaluate the study adequately.
Toxicity of Component Dyes
A summary of the toxicity and mutagenicity studies conducted with the two dye components of the new red-smoke formulation, disperse red 11 and solvent red 1, can be found in Appendixes G and E, respectively. In general, these dyes appear to have low acute toxicity, a mild irritation potential, and low mutagenicity. Solvent red 1 was found to produce
TABLE 3-1 Summary of Toxicity and Mutagenicity Studies Conducted with Solvent Red 1 and Disperse Red 11 Mixtures
Study Type |
Species |
Exposure Conditions |
End Points and Comments |
Reference |
Acute toxicity |
Rat, Fischer 344, M, F |
Oral, acute, 5 g/kg; solvent red 1 to disperse red 11,33.4:6.6 (Lot 1) |
1/10 died at 14 d, LD50 > 5 g/kg |
Smith et al. 1986 |
Acute toxicity |
Rabbit, New Zealand White, M, F |
Dermal, acute, 2 g/kg, 24 hr; solvent red 1 to disperse red 11, 33.4:6.6 (Lot 1) |
0/10 died at 14 d, LD50 > 2 g/kg |
Smith et al. 1986 |
Acute toxicity |
Rat, Fischer 344, M, F |
Inhalation, 0.1, 0.3, 1.0 g/m3, 6 hr; mixture not specified |
Nasal and lung lesions |
Lundy and Eaton 1994 |
Subchronic toxicity |
Rat, Fischer 344, M, F |
Inhalation, 0.03, 0.1, 0.3 g/m3, 6 hr/d, 5 d/wk, 13 wk; mixture not specified |
Restrictive lung disorder; body-weight decrease |
Lundy and Eaton 1994 |
Eye irritation |
Rabbit, New Zealand White, M, F |
0.1 g per eye; solvent red 1 to disperse red 11, 33.4:6.6 (Lot 1) |
3/3 positive; redness, chemosis, discharge, iritis; no irritation 2/3 by d 7; opacity in 1/3 on d 21 |
Smith et al. 1986 |
Dermal irritation |
Rabbit, New Zealand White, M, F |
0.5 g/kg, clipped skin, 24 hr; solvent red 1 to disperse red 11, 33.4:6.6 (Lot 1) |
Nonirritating |
Smith et al. 1986 |
Pulmonary hypersensitivity |
Mice, Balb/c, F |
0.3 g/m3, 6 h/d, 5 d/wk, 3+ wk iv challenge; solvent red 1 to disperse red 11, 87.3:8.0 |
Negative |
Sailstad et al. 1994 |
Contact hypersensitivity |
Mice, Balb/c, F |
Local lymph-node assay: 0.0001 g/d both ears, 3 d; solvent red to disperse red 11, 87.3:8.0 |
Negative |
Sailstad et al. 1994 |
Mutagenicity |
Salmonella typhimurium (strains TA1535, TA1538, TA98, TA100) +/- S9 |
0-200 µgper plate; disperse red 11 to solvent red 1 to terephthalic acid, 5:25:16 |
Negative |
Brooks et al. 1989 |
Abbreviations: M, male; F, female. |
contact hypersensitivity in experimental animals (Sailstad et al. 1994). Disperse red 11 was negative in the same study. The sparse toxicology data base for these two dyes prevents adequate assessment of potential toxicity. Especially lacking are long-term comprehensive studies of these chemicals after inhalation exposure in which multiple end points have been examined. Additionally, conflicting results are often obtained in acute toxicity studies of these dyes. The basis for the differences in experimental results obtained by various investigators is not known. One potential explanation might be variability in the nature and extent of impurities or contaminants in the individual dye lots. The impurities, rather than the dyes, might be responsible for observed toxicity and mutagenicity.
OVERALL EVALUATION OF TOXICITY
There are no well-controlled inhalation toxicity studies on the combustion products of the new yellow-, green-, and red-smoke formulations that could provide a basis for the subcommittee to assess the potential health effects of exposure to these combustion products by military personnel or to recommend guidance levels.
The subcommittee is concerned about the toxicity of several of the dye components. For new yellow-and green-smoke formulations, the major concern is the demonstrated contact allergic dermatitis in some humans exposed to solvent yellow 33. Thus, even masking will not protect against the dermal toxicity of solvent yellow 33. Although studies have been conducted on mixtures of the new yellow, green, and red dye components, no experimental studies have been conducted on the toxicity of the combustion products of the smoke-formulations. Therefore, toxicity of the combustion products cannot be evaluated directly. For all three smoke formulations, evaluation would be limited to extrapolation from studies conducted with either the individual dye components or dye mixtures. Because of minimal data base on the toxicity of the dyes as individual components or as mixtures, it is not prudent to extrapolate results from these studies to predict the potential toxicity of the combustion products of the new smoke formulations.
PREVIOUS RECOMMENDED EXPOSURE LIMITS
There are no previous recommended exposure limits for the combustion products of the new yellow, green, and red-smoke formulations. Army
Health Hazard Assessment Reports (AEHA 1992, 1993a,b) for the M18 smoke grenade and 40-mm cartridge components recommend masking when a smoke haze exceeds 4 hr or when passing through or operating in a smoke fog.
SUBCOMMITTEE RECOMMENDATIONS
The data base is inadequate for assessing the potential toxicity of combustion products of the new yellow-, green-, and red-smoke formulations to make recommendations for exposure guidance levels. The subcommittee recommends that acute inhalation studies be conducted in experimental animals to test the toxicity of the new yellow, green, and red smokes. Acute toxicity studies would be most appropriate for recommending the emergency exposure guidance level and the short-term public emergency guidance level. Such exposures might occur during training exercises in which military personnel might be exposed for several minutes, twice per day, two to four times per year. Some military personnel, particularly instructors involved in training exercises, might be repeatedly exposed to the smokes over several years, as might a community living near a military-training facility. For those exposure scenarios, the repeated exposure guidance level and the repeated public exposure guidance level are the most appropriate guidance levels, and studies assessing the potential toxicity of the smokes following repeated exposure would provide the most appropriate data for setting those exposure guidance levels. Thus, the Army should also consider conducting subchronic inhalation studies in experimental animals to test the toxicity of the smokes under conditions of repeated exposure. Both acute and repeated inhalation studies should be carried out using combusted smokes, and the particle size and combustion products should be representative of the smokes used by the Army. Toxicity testing of other smoke formulations or of individual dyes might not provide results similar to those obtained with the combusted smokes.
Additionally, concerns for potential sensitization resulting from exposure to solvent yellow 33, a component of the new yellow-and green-smoke formulations, and solvent red 1, a component of the new red-smoke formulation, suggest that studies to assess contact allergic dermatitis and respiratory-tract hypersensitivity should be conducted in animal models appropriate for testing hypersensitivity. Those studies should also be conducted using the combusted smokes. To ensure that such
studies are designed correctly, the Army should consult with an expert panel before conducting them.
At this time, the subcommittee recommends that Army policy regarding respiratory and dermal protection from these smokes be followed. It also recommends that the colored smokes be used for signaling and not for obscuring. The subcommittee recommends that the Army avoid exposing the general public to the combustion products.
REFERENCES
AEHA (U.S. Army Environmental Hygiene Agency). 1992. Initial Health Hazard Assessment Report (RCS MED 388) on the M18 Colored (Red, Green and Yellow) Smoke Grenade Components. 69-37-XN46-92. U.S. Army Environmental Hygiene Agency, Aberdeen Proving Ground, Edgewood, MD.
AEHA (U.S. Army Environmental Hygiene Agency). 1993. Health Hazard Assessment Report (RCS MED 388) on the 40 MM Colored Smoke Ground Marker. Report No. 69-37-XY57-93. U.S. Army Environmental Hygiene Agency, Aberdeen Proving Ground, Edgewood, MD.
AEHA (U.S. Army Environmental Hygiene Agency). 1993. Health Hazard Assessment Report (RCS MED) on the M18 Colored (Red and Violet) Smoke Grenade Components. Report No. 69-37-XN46-93. U.S. Army Environmental Hygiene Agency, Aberdeen Proving Ground, Edgewood, MD.
Brooks, A.L., F.A. Seiler, R.L. Hanson, and R.F. Henderson. 1989. In vitro genotoxicity of dyes present in colored smoke munitions. Environ. Mol. Mutagen. 13(4):304-313.
Buchanan, M.V. and C.Y. Ma. 1988. Chemical Characterization and Toxicologic Evaluation of Airborne Mixtures. Chemical Characterization of Colored Signal Smokes. Final Report. ORNL/TM-1195. AD A209379. Oak Ridge National Laboratory, Oak Ridge, TN.
Henderson, R.F., W.E. Bechtold, M.A. Medinsky, J.P. Fischer, and T.T. Lee. 1988. The effect of molecular weight/lipophilicity on clearance of organic compounds from lungs. Toxicol. Appl. Pharmacol. 95(3) 515-521.
Lundy, D., and J. Eaton. 1994. Occupational Health Hazards Posed by Inventory U.S. Army Smoke/Obscurant Munitions (Review Update). WRAIR/RT-94-0001. AD-A276-774. Prepared by U.S. Army Medical Research Detachment, Wright-Patterson Air Force Base, Ohio, for Walter Reed Army Institute of Research, Washington, DC.
Marrs, T.C., H.F. Colgrave, M. Gazzard, and R.F.R. Brown. 1984. Inhalation toxicity of a smoke containing Solvent yellow 33, Disperse red 9 and Solvent green 3 in laboratory animals. Human Toxicol. 3:289-308.
Marrs, T.C., H.F. Colgrave, N.L. Cross, J.A.G. Edgington, and B.C. Morris. 1988.
Inhalation toxicity of a coloured smoke and the mutagenicity of its constituent dyes, solvent yellow 33 (CI 47,000) and disperse orange 11 (CI 60,700) in the Ames test. J. Hazard. Mater. 17:269-285.
Mauderly, J.L. 1984. Respiratory function responses of animals and man to oxidant gases and to pulmonary emphysema. J. Toxicol. Environ. Health 13(2-3):345-361.
Medinsky, M.A., Y.S. Cheng, S.J. Kampcik, R.F. Henderson, and J.S. Dutcher. 1986. Disposition and metabolism of 14C-solvent yellow and solvent green aerosols after inhalation. Fundam. Appl. Toxicol. 7:170-178.
Sailstad, D.M., J.S. Tepper, D.L. Doerfler, M. Qasim, and M.K. Selgrade, 1994. Evaluation of an azo and two anthraquinone dyes for allergic potential. Fundam. Appl. Toxicol. 23:569-577.
Smith, S.H., G.L. Doyle, J.C. Kreuger, K.A. Mellon, and D.A. Mayhew 1986. Dermal, Eye and Oral Toxicological Evaluations, Phase IV Report, with Disperse Red 11, Disperse Blue 3, Solvent Red 1, and Red and Violet Mixtures. AD-A172758. American Biogenics, Decatur, IL.
Sun, J.D., R.F. Henderson, T.C. Marshall, Y.-S. Cheng, J.S. Dutcher. J.A. Pickrell, J.L. Mauderly, F.F. Hahn, D.A. Banas, F.A. Seiler, and C.H. Hobbs. 1987. The inhalation toxicity of two commercial dyes: Solvent yellow 33 and solvent green 3. Fundam. Appl. Toxicol. 8:358-371.