Lance A. Wallace
U.S. EPA
Atmospheric Research and Exposure Assessment Laboratory
Bldg 166, Bicher Road
Vint Hill Farms Station
Warrenton, VA 22186-5129
William C. Nelson
U.S. EPA
Atmospheric Research and Exposure Assessment Laboratory
Research Triangle Park, NC 27711
Edo Pellizzari
James H. Raymer
Kent W. Thomas
Research Triangle Institute
Research Triangle Park, NC 27709
Paper #A312 to be submitted for presentation at the 1991 Annual Meeting of the AWMA
March 1, 1991
INTRODUCTION
PB91-182865
Previous studies have shown that common personal activities(1) and emissions from building materials(2) or consumer products, particularly in enclosed spaces (microenvironments)(3) can elevate exposures to a number of toxic and carcinogenic volatile organic compounds
(VOCs). These earlier studies investigated about 25 personal activities, 50 building materials, and 32 microenvironments for a set of about 30
VOCs, mostly nonpolar aliphatic, aromatic, and halogenated compounds. These are of course only a small number of the hundreds or thousands of activities, materials, and microenvironments people encounter daily, and the chemicals are representative of only a few of the many classes of chemicals encountered daily.
In an attempt to broaden the number of microenvironments and chemical classes studied, the U.S. EPA sponsored a study of polar chemicals emitted from 31 consumer products and 16 microenvironments. Polar chemicals such as alcohols,
aldehydes, esters, and ketones are of interest because of their odorous and irritant properties. Complaints of odors and eye, nose, and throat irritation are often encountered, particularly in the office environment, as part of a complex of symptoms known as Sick Building Syndrome
(SBS)(4). Some people may be unusually sensitive to odors or irritant properties of these chemicals (chemical sensitivity)(5). Both SBS and chemical sensitivity may be widespread enough to have significant effects on the country's productivity and health care costs.
STUDY DESIGN
The study had three objectives:
1) Determine whether canister collection followed by GC-MS analysis would be capable of identifying (and, if possible, quantifying) polar VOCs collected in microenvironments and in the headspace of products.
2) Identify (and, if possible, quantify) all polar VOCs emitted by selected fragrance products.
3) Investigate microenvironments containing these products for the presence of these polar (as well as
nonpolar) VOCs.
The approach was to obtain standards for the various chemicals likely to be used in fragrance products and to determine whether the chemicals could be recovered quantitatively from the evacuated canister. If so, the products and microenvironments would be investigated quantitatively using the canister to collect headspace and microenvironmental samples.
If canister recoveries were low or variable, the canister would be supplemented by a direct injection method for the headspace analyses. This would allow comparison of the chromatograms from the two methods and identification of chemicals that were not recovered sufficiently by the canister. GC-MS analysis would provide for identification of the chemicals. However, the amounts of the chemicals would be determined only in a semiquantitative fashion.
A complete description of the study is provided in an EPA report(6).
METHODS
Standards for 34 chemicals used in perfumes, soaps, and other scented products were obtained and loaded into evacuated
Summa(tm) canisters at levels of about 50 ng/mL. The same standards were also used to form dilute solutions in methanol (about 50
ng/uL). The standards were analyzed both from the canister and through injection of the methanol solution into the glass injection port of the GC-MS system, which is described fully elsewhere(3). Recovery efficiencies were calculated by comparing the amount recovered from the canister to the amount recovered from the direct liquid injection.
The 31 scented product brands to be tested were chosen from a broad variety of product categories such as perfumes, soaps, and deodorants. Brand names were selected based on recommendations from persons who had experienced health symptoms or discomfort that they attributed to the product. Generally only one or two different brands were tested within a category. Since only one semiquantitative analysis was made for each sample, the results can not be interpreted as indicative of that sample's "actual" or "typical" composition; therefore brand names will not be revealed.
Scented products were tested using a headspace generation system. A snail amount of the product was placed in a headspace purge vessel and then a stream of slightly humidified N2 gas was directed through a port in the vessel. The gas stream was collected by a 1.8L canister with a restrictive orifice or went directly to the analytical instrument. The transfer line from the headspace purge vessel to the cryotrap was heated to 50° C. For canister analyses the transfer line was not heated, to better evaluate the typical mode of analysis of canister air samples. No dryer to remove excess humidity was used in either case, in order not to lose the polar chemicals along with the water vapor.
Canisters were used to collect 1.8L grab samples from 15 commercial establishments expected to contain scented products (potpourri stores, craft and hobby stores, etc.) and a few homes.
RESULTS
Of the 34 fragrance standards tested, nine were not recoverable from the methanol solution: linalool, linalyl acetate,
hydroxycitronellol, triethylamine, benzyl salicylate, hexyl cinnamaldehyde, mush
ambrette, eugenol, and furfuryl propionate. Recoveries of most of the remaining 25 chemicals from the canister were generally poor, typically getting worse with higher boiling points and lower volatilities. Since fragrances are selected partly for their ability to remain associated with the person or product, they tend to have low volatilities. These results indicate that the higher boiling compounds used in fragrances may not be recovered very well from passivated canisters, and that the sampling methodology may need to be changed to one that can better capture and release these compounds.
Because of the low recoveries for many compounds, the canister was supplemented, as planned, by a direct injection method for the headspace analyses. All 31 products were analyzed using the direct injection method. On 17 of these, the canister was also employed. It is interesting to note that canister recoveries appeared to improve when the much larger concentrations associated with the headspace of the scented products were sampled, as could be determined by comparing the headspace and canister chromatograms. Figures 1-3, typical of a number of these comparisons, show that for the products tested the canister matched the headspace chromatogram fairly well up to a retention time of 35-40 minutes, after which the response of the canister was degraded. Many of the fragrance standards (e.g., linalool) that had poor recoveries in the initial set of experiments showed up consistently in both the headspace and canister samples of the scented products.
All chemicals were identified but only semiquantitative estimates were provided for their concentrations in the microenvironmental and product samples. The chemicals with the highest concentrations (relative to the other chemicals) in each sample are listed in Table I.
A total of about 150 chemicals were identified in the 31 products, and about 100 chemicals in the 15 microenvironments. The chemicals appearing most often in the products and microenvironments are listed in Tables II and III.
DISCUSSION
The headspace analysis method employing direct injection through heated transfer lines with no dryer was capable of identifying some hundreds of polar and nonpolar VOCs emitted by the tested products. The method employing collection of headspace vapors in a canister, followed by nonheated transfer lines with no dryer, also gave useful semiquantitative results for many of these same polar and nonpolar chemicals, but with some degradation of performance noted for chemicals with higher boiling points. From previous studies, the point at which canister performance begins to degrade occurs roughly at the boiling point of n-dodecane(7). For chemicals with higher boiling points, a different collection medium such as Tenax may be more suitable, although this hypothesis needs to be tested in the case of the polar organics.
As can be seen from comparing Tables II and III, a different set of chemicals appeared to be found in the microenvironments compared with the scented products, despite the fact that many of these microenvironments were chosen because they contain these products. This may be due to the observed low recoveries that occur when the canister is employed in atmospheres with low concentrations of polar chemicals.
The 31 fragrance products tested contained a number of the same chemicals. Chemicals that appeared in more than half of these products included ethanol, limonene, linalool,
B-phenethyl alcohol, and B-myrcene. Ethanol is an alcohol used as a solvent base for many of these preparations. Limonene is a terpene contained in citrus fruits, pine trees, etc. and is a very popular additive to perfumes, soaps, polishes, room air fresheners, soft drinks , and innumerable other products. Linalool is found in cinnamon and lavender.
B-phenethyl alcohol is present in many flowers, and has a roselike scent. B-myrcene is found in bay leaves, verbena, and hops.
Many of the other chemicals found in the fragrance products are natural chemicals occurring in flowers, fruits, and trees(8). Their function in some cases appears to be to attract helpful insects such as bees; in other cases, the scents act as a.repellant (e.g., citronella). Few of these chemicals have been tasted for carcinogenicity, although some (e.g.,
a-pinene) are known mutagens and others (e.g., camphor) have known toxic effects at high concentrations(8). Limonene was tested for carcinogenicity and was observed to cause cancer in male rats, but not in mice or female rats(9).
Some of the brand names tested have been identified as being associated with mucous membrane irritation, weakness, or other symptoms in some people. If one or a few ingredients are responsible for the irritant health effects of some products, the results of the individual chemical analyses of these products (available on request from the authors) could be used to select likely individual chemicals for controlled experimental exposures.
The most common chemicals observed in the 15 microenvironments were toluene, methylene chloride, ethanol, 1,1
,l-trichloroethane, silane compounds, a-pinene, isopropanol, xylenes, and
undecane. Of these, only ethanol was among the five most common chemicals associated with the fragrance products. Toluene and xylenes are petroleum-based aromatic compounds widely used in paints, adhesives, and literally thousands of other products. Methylene chloride is a manmade halocarbon used in paint removers and many other solvents. l,l,l-trichloroethane is another halocarbon solvent used in hundreds of products including polishes and dry cleaning fluids.
a-pinene is a terpene found in pine and many other woods, and is a popular additive (pine scent) to polishes, soaps, air fresheners, etc. Decane and undecane are straight-chain hydrocarbons found in paints, adhesives, and building materials.
CONCLUSIONS
The canister method tested showed low recoveries on most of the 34 fragrance standards tested at low concentrations. However, at the higher concentrations encountered in the headspace of fragrances, both the direct injection method and the canister method were capable of identifying scores of polar VOCs emitted from products. The most common of these polar VOCs were identified, and included alcohols, esters, and
aldehydes. Since some of these polar VOCs are associated with irritation, odors, and other health and comfort concerns(4), identification without quantitative measurements may be useful in determining chemicals emitted by a suspect source. Some evidence of reduced canister recoveries for polar VOCs with high boiling points was noted; a different collection method may be required for polar VOCs with boiling points greater than that of
n-dodecane.
Many of the chemicals detected in the fragrance products are naturally derived from plants(7). Although 150 different chemicals were detected in 31 such products, a rather small sat of these natural fragrances appeared in many of the products. Thus if one or more of these chemicals are responsible for the human health reactions to fragrant products reported by many(5), it could be possible to carry out a testing program on the set of 15-20 chemicals reported here as appearing repeatedly in these products. It would also be possible to use the methods described here to identify chemicals of interest in other products associated with health symptoms or comfort complaints.
DISCLAIMER
This paper is based on research sponsored by the Environmental Protection Agency but does not necessarily reflect EPA policy.
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REFERENCES
1. L.A. Wallace, E. Pellizzari, T. Hartwell, V. Davis, L. Michael, and R. Whitmore, "The Influence of Personal Activities on Exposure to Volatile Organic Compounds," Environ. Res. 50:37-55, 1989.
2. L. Sheldon, L. Wallace, et al., Indoor Air Quality in Public Buildings: Vols. I and II
USEPA, Research Triangle Park, NC EPA 600/S6-88/009a,b. 1988.
3 E.D. Pellizzari, K.W. Thomas, J.H. Raymer, D.J. Smith, and S.D. Cooper, Breath measurements of Individuals Exposed to Chemicals During Personal Activities, Final Report, EPA Contract #68-02-4544, Work Assignment II-40, 1990.
4. Molhave, L., Bach, B. and Pedersen, O. "Human Reactions to Low Concentrations of Volatile Organic Compounds," Environ Inter 12:167-175, 1986.
5. Ashford, N.A. and Miller, C. Chemical Exposures: Low Levels and High Stakes. Van Nostrand Reinhold, New York. 1991.
6. J.H. Raymer, E.D. Pellizzari, S.D. Cooper, N.P. Castillo, and K.W. Thomas, Evaluation of a Pharmacokinetic Model for Volatile Organic Compounds in Breath and of the Application of the Analytical Method to Polar
VOCs, final report, EPA Contract #68-02-4544, Work Assignment #II-80, 1990.
7. E.D. Pellizzari, K.W. Thomas, J.H. Raymer, D.J. Smith, and S.D. Cooper, Breath Measurements of Individuals Exposed to Chemicals During Personal Activities, Final Report on EPA contract 68-02-4544. Work Assignment II-40. 1990.
8. The Merck Index, 11th Edition. Merck & Co., Rahway, NJ. 1990.
9. National Toxicology Program, NTP Technical Report on the Toxicology and Carcinogenesis Studies of d-Limonene, National toxicology Program, Research, Triangle Park, NC. 1988.
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Table I. Number of chemicals identified and principal chemicals present in products tested and locations sampled.
Product N(a) Principal chemicals (b) perfume #1 55 linalool, limonene, ethanol, B-citronellol perfume #2 24 linalool, a-terpineol, limonene, benzyl acetate perfume #3 28 linalool, unknown, 1,8-cineole, neryl acetate cologne #1 49 limonene, linalool, B-phenethyl alcohol cologne #2 45 limonene, a-guaiene, C15H24 bar soap #1 54 limonene, a,B-pinene, linalool bar soap #2 40 limonene, linalool, other alcohols shampoo 25 linalool, benzyl acetate, B-citronellol hairspray #1 19 fluor compounds, benzaldehyde, silane compound hairspray #2 17 unknown, butene, butane, ethanol, C11H24O, isopentone, a-terpineol, isobutane shaving cream 17 limonene, propanal after shave lotion 19 menthol, B-citronellol solid deodorant #1 34 hexamethylcyclotrisiloxane , trimethylsilane, limonene, linalool solid deodorant #2 12 limonene spray deodorant 26 silane compounds, limonene hand lotion 22 unknown, linalool nail color 18 camphor, unknown, alcohol ? (c) nail enamel remover #1 12 benzyl alcohols, linalool, B-citronellol, limonene, B-phenethyl alcohol nail enamel remover #2 14 limonene, ethyl acetate, a-terpinolene, nerol, C10H18O detergent powder 20 a-terpineol, linalool bleach powder 25 a-terpineol, linalool, C12H2202 (acetate) fabric softener #1 23 benzyl acetate, limonene, y-methyl ionone, linalool, ester (?), ethanol fabric softener #2 28 ester (?), C12H2202 (acetate), Iinalool, a-terpineol, B-citronellol, C14H22O (alcohol) dishwashing liquid #1 19 limonene, ethanol, acetone dishwashing liquid #2 15 limonene, styrene dishwasher detergent 19 terpinyl acetate liquid air freshener 29 linalool, limonene, alcohol, Cl0H18O, Cl0H20O solid air freshener 24 alcohols, limonene, Cl0H18O (?), camphor spray air freshener 16 fluor compound, limonene, C15H24, ethanol correction fluid 16 trichloroethylene, ethylene dichloride paint remover 8 toluene, methylene chloride department store 25 toluene, p-dichlorobenzene, ethanol clothing store 28 ethanol, isopropanol shopping mall 29 ethanol, isopropanol potpourri shop 33 ethanol, toluene craft/hobby store #1 31 isopropanol, l,l,l-trichloroethane craft/hobby store #2 31 isopropanol, unknown auto part shop 30 toluene, methylene chloride, tetrachloroethylene tire shop 17 l,l,l-trichloroethane tire warehouse 27 l,l,l-trichloroethane carpet store 24 1,1,1-trichloroethane grocery, detergents 28 limonene, tetrachloroethylene grocery, pet foods 18 limonene, tetrachloroethylene health club 17 ethanol, silane compound room with air freshener 14 p-dichlorobenzene, ethanol closet with cedar chips 22 ethanol, limonene new shower curtain 16 decane, ethylene dichloride (a) Number of chemicals identified in headspace or canister sample (b) In order of relative amounts (c) Identification tentative
Table II. 20 most common chemicals found in 31 fragrance products.
CHEMICAL N (a) ethanol 23 limonene 23 linalool 22 B-phenethyl alcohol 21 B-myrcene 17 benzyl acetate 15 benzyl alcohol 15 benzaldehyde 14 a-terpineol 14 ocimene 13 B-citronellol 13 a-pinene 12 acetone 11 ethyl acetate 11 y-terpinene 11 1,8-cineole 10 a-terpinolene 9 nerol 9 camphor 8 methylene chloride 8 (a) Number of times chemical identified in headspace of 31 products
Table III. 15 most common chemicals found in 15 microenvironments.
CHEMICAL N(a) toluene 15 methylene chloride 14 ethanol 12 l,l,l-trichloroethane 12 silane compound 12 a-pinene 11 isopropanol 11 m,p-xylene 11 n-undecane 11 n-decane 10 limonene 10 chlorodifluoromethane 9 acetone 9 trimethylbenzene isomer 8 n-nonane 7 (a) Number of times chemical identified in 15 microenvironments
source: http://www.ourlittleplace.com/epa.html 8dec03
Also see: http://www.epa.gov/heasd/emab/staff/wallace.htm
Clayton, C. Andrew, Rebecca L. Perritt, Edo D.
Pellizzari, Kent W. Thomas, Roy W. Whitmore, Lance A.Wallace, Haluk Ozkaynak,
and John D. Spengler, “Particle Total Exposure Assessment Methodology (PTEAM)
Study: Distributions of Aerosol and Elemental Concentrations in Personal,
Indoor, and Outdoor Air Samples in a Southern California Community,” Journal
of Exposure Analysis and Environmental Epidemiology,
Vol. 3, No. 2, 1993, pp. 227-250.
Annual Review of Energy and the Environment Nov 2001, Vol. 26, pp. 269-301 (doi:10.1146/annurev.energy.26.1.269) HUMAN EXPOSURE TO VOLATILE ORGANIC POLLUTANTS: Implications for Indoor Air Studies1
Lance A. Wallace
US Environmental Protection Agency, Reston, Virginia 20191; e-mail: wallace.lance@epa.gov
Abstract Over the past 20 years, a new scientific discipline based on direct
measurement of human exposure to environmental pollutants has developed. The
fundamental principle of the new science is to "measure where the people
are." This has required developing small, lightweight, quiet personal
monitors for volatile organic compounds and other pollutants. A second principle
has been to measure body burden, particularly exhaled breath, whenever possible
to determine the relationship between exposure and dose. Studies employing the
new monitors and breath measurements have overturned accepted ideas about the
sources of most volatile organic pollutants. The main sources turn out
surprisingly often to be small, close to the person, and completely unregulated.
These findings should result in major changes in our approach to environmental
regulation; however, powerful forces of resistance would need to be overcome.
1 The US government has the right to retain a nonexclusive, royalty-free license in and to any copyright covering this paper.
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