People are often unaware of the numerous chemical exposures they encounter daily-in the air they breathe, the water they drink, the food they eat, and the products they use to clean and disinfect their homes. Cleaning and disinfectant products can contain multiple chemicals including volatile organic compounds (VOCs), which are used as solvents, fragrances, or preservatives.1
When sprayed, cleaning and disinfectant products can aerosolize both asthma-associated VOCs and nonvolatile compounds, which then may be inhaled.1, 2 Such exposure to cleaning and disinfectant products has been shown to be related to adult-onset asthma, and occupational exposures have been shown to increase asthma-related symptoms and exacerbations.3, 4 While the precise biological mechanism by which cleaning and disinfectant products affect the respiratory system isn't clear, studies have shown that they may function as both irritants and allergens,3 producing oxidative stress, inflammation, and irritation.
Residential exposure. Although the occupational effects of cleaning and disinfectant products on adults with asthma have been widely explored, scant research has focused on the effects of residential exposure to these products on asthma control. Several recent European studies have investigated the relationship between use of cleaning and disinfectant products and asthma. One study involving 607 women (mean age, 44 years) in which analyses were adjusted for age, smoking (never, former, current), body mass index of 25 or higher, and occupational exposure to asthmagens reported that frequent bleach use at home was significantly associated with nonallergic asthma (adjusted odds ratio [aOR], 3.30; 95% confidence interval [CI], 1.53-7.13).5 For women who used bleach four to seven times per week, the association between bleach use and current asthma was borderline significant when adjusted for age (aOR, 1.70; 95% CI, 0.98-2.95; P = 0.06).5
Another study found that the risk of asthma increased not only with the use of cleaning and disinfectant products and the frequency of use, but also with the number of products used.6 Furthermore, a study that included 2,223 women ages 64 to 76 years found that weekly use of cleaning and disinfectant products by older women was associated with "poorly controlled" asthma.7
In this article, we describe the tools nurses and their patients can use to make smart choices about the cleaning and disinfectant products they use in their homes. We discuss how the Environmental Working Group (EWG) rates these products and report the findings of a recent study we conducted that identified cleaning and disinfectant products that could reduce asthma control in older adults. We also describe precautions people of all ages who have asthma or other respiratory conditions should take when deciding how to safely clean and disinfect their homes.
ENVIRONMENTAL WORKING GROUP RATINGS
One publicly available resource for accurate information about cleaning and disinfectant products is the EWG. The mission of the EWG, as stated on its website (http://www.ewg.org), is to provide research that empowers people "to make informed choices and live a healthy life in a healthy environment." The EWG website includes consumer information on a wide range of issues and products that affect human health and the environment, including contaminants in water; pesticides in food; ingredients in personal care products such as shampoos, toothpastes, deodorants, and cosmetics; and cleaning and disinfectant products. The EWG's Guide to Healthy Cleaning rates more than 2,500 products based on five categories: asthma and respiratory concerns, skin allergies and irritation, developmental and reproductive toxicity, cancer, and overall environmental impact.8
Within these categories, products are then assigned a rating of concern: low concern, some concern, moderate concern, or high concern. In addition, products are assigned an overall grade of A to F: A indicates that the product discloses its ingredients and has a very low toxicity to health and the environment, C indicates that the product discloses some ingredients and has no overt hazards, and F indicates that either the ingredients are not disclosed or the product is highly hazardous.9
To determine these ratings, EWG staff evaluate the ingredients listed on product labels and websites, material safety data sheets submitted to the Occupational Safety and Health Administration, U.S. and European toxicity data sources, and scientific literature.9
Ingredients, however, are not always disclosed because industries consider some formulations to be proprietary trade secrets, and scientific data on some chemicals and their cumulative or synergistic effects are inconclusive or nonexistent. The United States does not require a review of chemicals in cleaning products, nor are manufacturers required to list all ingredients.10
OUR STUDY OF CLEANING PRODUCT USE AND ASTHMA CONTROL IN OLDER ADULTS
We recently conducted a study to determine whether asthma control varied based on older adults' cleaning practices (participant recruitment and data collection procedures are published elsewhere11). Between 2015 and 2020, we collected data on the cleaning practices of older adults with asthma and the cleaning and disinfectant products they used. We focused on older adults because much of the research on asthma has focused on children and adolescents, and very little has been published about asthma in older adults.
Study goals. The goals of our study were as follows11:
* to develop a phenotyping algorithm for this population (an abstract that addresses this phenotyping has been published,12 and our manuscript on the subject is currently under review)
* to explore the effects of asthma phenotypes and VOCs on asthma control
* to produce a predictive model of asthma quality of life
Setting. The Greater Louisville region in Louisville, Kentucky
Inclusion and exclusion criteria. Participants were required to be nonsmokers, to be at least 60 years of age, and to have a confirmed diagnosis of asthma.11 Excluded were current smokers, former smokers who quit less than five years ago or had a smoking history of 20 pack-years or more, those who had a comorbid pulmonary disease or resided in a skilled nursing facility, and those with a prognostic index score of 10 or higher,11 which is predictive of a 42% four-year mortality risk.13
Recruitment. Participants were recruited from pulmonologist and allergist offices; through social media, press releases, church newsletters, and flyers posted in clinics and senior citizen centers; and through local television and radio appearances.11
Initial screening and testing. Potential participants were contacted by email or phone to determine potential eligibility.11 Those who passed the initial screening were scheduled for pulmonary function testing.
Demographics. Participants were primarily female, White, college graduates, and retired or unemployed; most had health insurance, owned their own homes, were diagnosed with asthma as adults, and ranged in age from 60 to 96.11
Data collection. Data were collected at baseline and at nine and 18 months postbaseline. Baseline data were collected at the Clinical Trials Unit of the University of Louisville and at participants' homes.11 All nine- and 18-month data were collected at participants' homes. Data were analyzed descriptively, and differences by Asthma Control Test (ACT)14 score groupings were analyzed using an independent-samples Kruskal-Wallis test, since the data were not normally distributed. The level of significance was set a priori at P <= 0.05.
Baseline physiological measures included pulmonary function testing, fractional exhaled nitric oxide, skin prick testing, and immunoglobulin E.11 Self-report measures included demographics, asthma control, asthma quality of life, asthma knowledge, and asthma self-efficacy.
A total of 185 participants completed baseline pulmonary function testing, questionnaires, sputum induction, skin prick testing, and had blood drawn for measuring vitamin D and immunoglobulin E.
Environmental data. Within 30 days of enrollment, we collected baseline environmental data in participants' homes, where we asked them about the cleaning and disinfectant products they used and how often they had used them in the past 14 days. During these visits, we were able to visually confirm the specific types of products used. We confirmed the products used by 148 (80%) of the 185 participants.
Our study focused only on the 148 participants for whom we could visually confirm specific cleaning and disinfectant products. We categorized these products on a scale of 1 to 4 in accordance with the EWG asthma and respiratory health concern ratings (low = 1, some = 2, moderate = 3, and high = 4).
An exposure scale. Through conversations with study participants, we obtained specific information about their cleaning practices and the types of cleaning and disinfectant products they used, which enabled us to develop a scale that combined EWG asthma and respiratory impact ratings of the products with data on the frequency of use. The Cleaning Product Exposure Scale used the following formula to indicate the extent of each participant's exposure to cleaning products:
EWG product asthma/respiratory rating x number of times shower/bathroom cleaned in past 2 weeks
Asthma control. To determine participants' level of asthma control over the past four weeks, we asked them to complete the five-item ACT.11, 14 Based on their ACT scores, participants' asthma control was categorized as follows15:
* "very poorly controlled" (<= 15); 27% of participants
* "not well controlled" (16 to 19); 28.4% of participants
* "well controlled" (>= 20); 44.6% of participants
OUR STUDY FINDINGS
Cleaning frequency. Over the previous 14 days, participants had scrubbed their shower or tub a mean (SD) of 3.1 (3.9) days. Those with very poorly controlled asthma reported scrubbing their shower or tub a mean of 4.8 (5) days, significantly (P = 0.026) more often than those whose asthma was either not well controlled (mean, 2.1 [2.4] days) or well controlled (mean, 2.7 [3.5] days).
Commonly used cleaning and disinfectant products. Most participants (91.2%) used commercial cleaning and disinfectant products, the most common of which were Scrubbing Bubbles all-purpose cleaner (n = 38), Lysol products (n = 15), Comet powder with bleach (n = 10), and Kaboom Shower, Tub, and Tile Cleaner (n = 8). Most cleaning and disinfectant products (60%) were categorized by the EWG as having moderate asthma and respiratory health concerns. (See Table 1 for the full list of products used by study participants and their EWG ratings.8) Vinegar and baking soda, used alone or in combination, were the most common noncommercial cleaners used (n = 12) and were categorized as having low asthma and respiratory health concerns.
Exposure scores, which ranged from 0 to 42 (mean, 7.7 [10.2]), with higher numbers indicating higher potential frequency of chemical exposure, were significantly (P = 0.012) higher for those with very poorly controlled asthma (mean, 12.5 [13.5]; median, 6) than for those with not well controlled (mean, 5.1 [5.5]; median, 4) or well controlled asthma (mean, 6.5 [9.3]; median, 3), indicating that participants with very poorly controlled asthma were cleaning more often within a 14-day period and using products with a more detrimental effect on their asthma control.
PURCHASING CONSIDERATIONS AND ASTHMA CONTROL
Asthma is a complex diagnosis, and health care providers are still uncertain as to how it develops. Once asthma is diagnosed, however, steps can be taken to reduce asthma triggers in the home and prevent asthma exacerbations. (See Table 216, 17 and Online Resources for Safer Cleaning Practices for People with Asthma.) Learning the negative effects of VOCs on asthma outcomes is an important step in reducing asthma triggers in the home.
Tools health care professionals and their patients can use to assist in reducing asthma triggers include the EWG's Guide to Healthy Cleaning (http://www.ewg.org/guides/cleaners) and the U.S. Environmental Protection Agency Safer Choice program (http://www.epa.gov/saferchoice). Both provide resources that can guide purchase options, provide lists of products determined to be "green" or safe, and assist in a purposeful review of the chemical exposures present in the home.
For patients with asthma, the first step is to create an inventory of products used for routine cleaning and the various places they're stored in the home. Once this list is in hand, ratings for each cleaning product can be accessed using the EWG's Guide to Healthy Cleaning.
As we found in our study of older adults with asthma, exposure to specific cleaning products and frequency of use are related to very poorly controlled asthma in older adults. Although our study focused on older adults, the EWG asthma and respiratory health concern ratings for cleaning and disinfectant products apply to people of all ages. To ensure that homes are a safe haven for all household members, it's important to take stock of household cleaning products and identify which are safe to use and which can be eliminated. A clear understanding of the negative effects of certain cleaning and disinfectant products can influence patients' purchasing habits and have a positive effect on their respiratory health and that of their household members.
Online Resources for Safer Cleaning Practices for People with Asthma
American Lung Association
http://www.lung.org
Asthma and Allergy Foundation of America
http://www.aafa.org/indoor-air-quality
Asthma and Allergy Friendly Certification Program
http://www.asthmaandallergyfriendly.com/USA
Environmental Protection Agency Identifying Greener Cleaning Products
http://www.epa.gov/greenerproducts/identifying-greener-cleaning-products
National Center for Healthy Housing Healthy Homes Guide to Cleaning and Disinfection
https://nchh.org/information-and-evidence/learn-about-healthy-housing/safe-clean
REFERENCES