RIFM RESPIRATORY SAFETY PROGRAM

INDOOR AIR QUALITY

Over the past several decades there has been an increase in the use of fragranced products and awareness of odors. Some of this awareness focuses on public perception regarding the decrease in indoor air quality (IAQ). Second hand smoke is the most often cited source of decreasing IAQ. Other important aspects of IAQ not related to fragranced products are the mold and biocontaminant issues. Molds have been closely associated with the exacerbation of asthma. Fragrance products may give the air a more pleasant smell (or no smell at all), but they cannot clean the air. Clean air and improved IAQ are dependent upon good housekeeping, sanitization, and elimination of items that encourage mold (and dust mite) contamination.

Recently, the use of fragranced products has been receiving more attention as an additional source of indoor air pollution. This is contrary to the intention of these products. They are intended to impart a feeling of well-being (aromatherapy is a common mood enhancer), a comfortable indoor setting, and a sense of freshness to indoor air. Fragranced products are used to enhance religious ceremonies (e.g. incense), special occasions, and seasonal or holiday times (e.g. floral scents, grass, pine). Often fragrance can be used to increase personal performance or enhance the appeal of other products (e.g. the “new car” smell).

Individuals may respond negatively to fragrance, psychologically or physiologically. When breathing scents, some people may not perceive them at all or they may perceive them as pleasant, acceptable, or offensive. Sensitive individuals may have a strong adverse response to fragranced air and suffer respiratory distress. Some fragranced products produce no discernible odor of their own but are effective in minimizing bad odors in indoor air. People may complain of allergic responses, general discomfort, and a variety of unspecific symptoms such as headache, nasal irritation, watery eyes, etc.

While it is well known that air fresheners are widely used in many public places, most commonly, in rest rooms, products also exist that introduce fragrances into circulating air at its origin. Many new buildings do not have windows that open; therefore, indoor air is recirculated, sometimes with partial dilution by fresh air from the outside to minimize the sense of staleness. There is concern that compounds from air fresheners may react with materials in the air, such as ozone, to form aldehydes, ketones, organic acids, particulates, and free radicals. Some of these reactants may be associated with mucous membrane irritation in addition to an unpleasant odor. This sort of contamination, with its subsequent complaints, falls into the category of the “sick building syndrome.” The recirculated air, containing off-gasses of construction and office materials as well as cleaning agents and kitchen odors, may eventually become exhaust air and contribute to outdoor air pollution.

People want to know the health effects of inhaled fragrances, particularly in conjunction with skin exposure. Other questions arise, such as: are individuals in the work place showing an increase in allergy or sensitivities to fragrances because of increased use of fragrance products? How can fragrance sensitive people be protected?

RIFM’s RESPIRATORY SAFETY PROJECT

Consumers exposed to inhaled chemicals are concerned about asthma, lung disease and neurological effects and whether these problems may be caused or aggravated by inhaling fragrance.

The objective of RIFM’s Respiratory Safety Project is to test the safety of exposure to inhaled fragrance materials when consumer products are used as intended. The research approach first characterizes exposures from representative materials in different product applications and then examines the potential for those exposures to cause physiological and/or psychological effects during normal use. Human lung function, respiratory and sensory irritation are considered to be the most appropriate indicators.

Representatives of the fragrance industry, RIFM‘s Expert Panel, and outside technical experts met to develop an experimental approach. Subsequently, a smaller Working Group was formed to help design research protocols and interpret results.

The first step gathered accurate exposure information from intended uses. The critical questions were the choice of product types and applications and the fragrance ingredients to use as markers. The representative product types chosen for evaluation were a pressurized aerosol air freshener, a heated oil plug-in air freshener, a fine fragrance, and a candle. The selected fragrance materials are:

* a Hexylcinnamaldehyde

**1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-g-2-benzopyran

Biological endpoints that may be of concern were determined by controlled exposures at recommended or slightly exaggerated use rates taking into consideration volatility, structure and effect.

Once atmospheres and potential human exposures are known, the next step will be to conduct a clinical study to investigate the cause/effect relationship between fragrance exposure and any potential adverse outcomes. Normal and sensitive populations will be considered. One indicator of an adverse effect is thought to be sensory irritation as measured by lung function, although changes may occur only in very severe cases. Other physiological indicators will be considered such as nasal resistance and transport, nasal lavage, and acoustic rhinometry.

Both biological and psychological relationships will be examined in the clinical study. Odor perception, annoyance, and influence will be characterized to determine how they might influence biological effect. Understanding these relationships will add perspective to complaints of adverse effects from exposure.

Finally, mechanistic studies may be important to understand cellular causes for any adverse effects. They may provide more reliable or more predictive tools for screening and evaluating mixtures and identifying relevant biomarkers.

The Respiratory Safety Project research results, to date, have been presented at scientific meetings and manuscripts have been submitted for publication in peer reviewed journals.

References

Isola, D. and Rogers, R. 2002. Airborne levels of selected fragrance materials in a simulated bathroom. International Journal of Toxicology, 21(6), 526. Presented at the American College of Toxicology Annual Meeting, November 10-13, 2002. Hershey, Pennsylvania, USA

Rogers, R.E., Isola, D.A., Jeng, C. J., Dews, P., Myshaniuk A., and Smith L.W. 2003. Characterization of potential human exposure to fragrances during residential consumer product use. J. Allergy Clin. Immunol., 111(2):S239. Presented at the American Academy of Allergy, Asthma and Immunology Annual Meeting, March 7-14, 2003. Denver, Colorado, USA.

Isola, D.A., Ansari, R., Black, M.S., Cortes, D.R., and Smith L.W., 2003. Exposure characterization from a fragranced plug-in air freshener. The Toxicologist, 72(S-1):291. Presented at the Society of Toxicology Annual Meeting, March 9-14, 2003. Salt Lake City, Utah, USA.

Isola, D.A., Smith, L.W., Rogers, R.E., and Black, M.S., 2003. Exposure characterization of fragranced air fresheners. J. Allergy Clin. Immunol. Int., S1:132. Presented at the World Allergy Organization Congress, September 6-13, 2003. Vancouver, British Columbia, Canada.

Isola, D.A., Rogers, R.E., Myshaniuk, A., Jeng, C. J., Ansari, R., and Smith, L.W. 2004. Exposure characterization from a fine fragrance. The Toxicologist, 78(S-1):518. Presented at the Society of Toxicology Annual Meeting, March 21-25, 2004. Baltimore, Maryland, USA.

Smith, L.W., Isola, D.A., Rogers, R.E. and Black M.S., 2004.  Exposure characterization of fragranced products. Presented at the International Congress of Toxicology, July 11-15, 2004. Tampere, Finland.

Cortes, D.R., Isola, D.A., Ansari, R., Black, M.S., and Smith, L.W.  2004.  Characterization of fragrance exposure concentrations and temporal trends from a plug-in air freshener.  Podium presentation at the American Industrial Hygiene Conference and Exhibition, May 8-13, 2004.  Atlanta, Georgia, USA.

Jeng, C. J., Isola, D.A., Myshaniuk, A., Rogers, R.E., and Smith, L.W.  2004.  Characterization of aerosol and fragrance exposure to two surrogate consumer fragrance products.  Submitted for presentation at American Association for Aerosol Research Annual Conference, October 4-8, 2004.  Atlanta, Georgia, USA.

Rogers, R.E., Isola, D.A., Jeng, C.-J., Dews, P., Myshaniuk, A., and Smith L.W., 2003. Characterization of potential human exposure to fragrances during residential consumer product use. Submitted for publication to: The Journal of Exposure Analysis and Environmental Epidemiology.

Isola, D.A., Ansari, R., Black, M.S., Cortes, D.R., and Smith, L.W., 2003. Exposure characterization from a fragranced plug-in air freshener. Submitted for publication to: The Journal of Exposure Analysis and Environmental Epidemiology.