Volatile Organic Compound Emissions from Disinfectant Usage in the Home and Office

Introduction

Commercial disinfectant products are known to contain toxic volatile organic compounds (VOCs) that may pose risks to people’s health if not used according to recommended guidelines.¹ Exposure to VOCs from indoor use of disinfectants increased during the COVID-19 pandemic.² In this study, we quantified VOC emissions in the air from the use of disinfectants in residential and educational settings, with the objective of gaining insights on exposure levels and potential health risks.

Methods

We selected five disinfectant products to represent a variety of common active ingredients, including those recommended for use against bacteria, viruses, and SARS-CoV-2³: Clorox Clean-Up Cleaner+Bleach Original (1.84% sodium hypochlorite), Lysol Power Bathroom Cleaner (2.50% citric acid), diluted Clorox Regular Bleach (0.1% sodium hypochlorite), LabChem Reagent Grade Isopropyl Alcohol (70% isopropanol), and Ecolab Peroxide Multi Surface Cleaner and Disinfectant (8% hydrogen peroxide). We tested products initially in two educational spaces (office room and classroom), and Clorox Clean-Up Cleaner+Bleach Original (1.84% sodium hypochlorite) and Lysol Power Bathroom Cleaner (2.50% citric acid) were additionally tested in residential spaces (apartment and house kitchens and bathrooms), as summarized in Table 1. Each product was sprayed with a ratio of 1 spray/${3\mathrm{m}}^3$ of room volume directly onto desktop and counter surfaces. Products were allowed to sit for 2 min and then wiped dry with paper towels.

Table 1.

Summary of experimental conditions of each indoor space tested. Each disinfectant product was sprayed with a ratio of 1 spray/${3\mathrm{m}}^3$ of room volume directly onto desktop or counter surfaces. Windows (if present) were closed during the application.

Room type	Trials ($n$)	Room volume (${\mathrm{m}}^3$)	Room ventilation (${\mathrm{m}}^3/\mathrm{s}$)	Windows ($n$)	Sprays ($n$)
Apartment bathroom	4	16	14	0	6
Apartment kitchen	4	17	14	1	6
House bathroom	4	14	21	1	5
House kitchen	2	32	21	1	11
Large classroom	2	303	1,600	0	103
Small classroom	5	171	900	3	58
Small office 1	22	30	100	0	10
Small office 2	2	30	100	1	10

Note: Each disinfectant product was pilot tested in both the small office 1 and the small classroom. Clorox Clean-Up Cleaner+Bleach Original and Lysol Power Bathroom Cleaner were then tested in all other rooms, with additional tests performed in small office 1.

Indoor air samples were taken with Markes TenaxTA-Sulficarb sorbent tubes before, during, and up to 1 h after cleaning with the disinfectant products. The sorbent tubes were pumped with 1 L of air for 5 min total. Sampling during disinfection was immediately after product application through 5 min, including 2 min of sitting time and wiping dry. We subtracted sample concentrations before product use from those during disinfection to adjust for differences in the air normally in the spaces.

We quantified 112 VOCs, including alcohols, hydrocarbons, aromatics, halogenates, and terpenes via thermal desorption–gas chromatography–mass spectrometry (TD-GC-MS) analysis adapted from the U.S. Environmental Protection Agency (EPA) TO-17 method.^4,5 Targeted VOCs and limits of detection (LODs) are described in a supporting data set.⁶ Measured VOCs included several carcinogenic compounds: benzene, carbon tetrachloride, chloroform, 1,4-dioxane, methylene chloride, and tetrachloroethylene.⁷

Results and Discussion

Of the five products tested, the highest number of VOCs during disinfection occurred with Clorox Clean-Up Cleaner+Bleach Original, followed by Lysol Power Bathroom Cleaner. The highest mean concentrations of VOCs were measured during disinfection with LabChem Reagent Grade Isopropyl Alcohol, which had the highest concentration of any active ingredient, 70% isopropanol.⁶ Isopropanol was detected above the upper LOD but was $>99\%$ of the total VOCs for this product.⁶ Summary statistics for compounds with a detection frequency of $>20\%$ are found in the supporting data set, including the mean, standard deviation, range, number of nondetects (NDs), and total VOCs in the sampling for each disinfectant.⁶

Figure 1 shows the highest concentrated or most frequently detected VOCs in the various room settings tested for two disinfectants, Clorox Clean-Up Cleaner+Bleach Original and Lysol Power Bathroom Cleaner. Ethanol was the highest VOC observed in these products, with a mean of 33 ppbv in the apartment bathroom during Clorox Clean-Up Cleaner+Bleach Original usage and $>\mathrm{1,149}$ ppbv after Lysol Power Bathroom Cleaner usage in the home bathroom and kitchen (Figure 1). However, these concentrations were well under the short-term exposure limit (STEL) of 1,000 ppmv for ethanol.⁸ Higher measured concentrations of ethanol were observed in rooms with lower ventilation (Table 1).

Figure 1.

Mean concentrations of most abundant or detected volatile organic compounds (VOCs) in different rooms tested after usage of (A) Clorox Clean-Up Cleaner+Bleach Original and (B) Lysol Power Bathroom Cleaner. Full data set and statistical summary are available in the supporting data set.⁶

Chloroform, classified by the U.S. EPA as a possible carcinogen to humans based on animal data,⁷ was measured up to 35 ppbv and mean of 8 ppbv in a small office—the second highest concentration among room types after Clorox Clean-Up Cleaner+Bleach Original usage (Figure 1). Other chlorinated compounds, such as carbon tetrachloride and methylene chloride, were found during Clorox Clean-Up usage at concentrations ranging from ND to 1.1 and 0.6 ppbv, respectively (Figure 1). Terpenes, including d-limonene, camphor, and borneol, were detected after Lysol Power Bathroom Cleaner usage and likely had been added to the product as fragrance. Use of both disinfectants yielded detectable levels of isopentane and isoprene (Figure 1).

Diluted Clorox Regular Bleach, Ecolab Peroxide Multi Surface Cleaner and Disinfectant, and LabChem Reagent Grade Isopropyl Alcohol produced concentrations of chloroform, carbon tetrachloride, methylene chloride, and benzene $<0.5$ ppbv in a small office and classroom.⁶ Isopropanol was released upon usage of LabChem Reagent Grade Isopropyl Alcohol, as expected, but exceeded the upper LOD via the methods here. Estimates of $>8.4$ ppmv, compared with the STEL of 500 ppm,⁸ suggest isopropanol was still below the STEL, even though it was $>100$ times as concentrated as any other VOC measured in our studies.⁶ The total VOCs measured were highest for LabChem Reagent Grade Isopropyl Alcohol ($>5.9\text{\hspace{0.17em}ppmv}$, 99% of which was isopropanol), followed by Clorox Clean-Up Cleaner+Bleach Original (10.1 ppbv), Lysol Power Bathroom Cleaner (227 ppbv), diluted Clorox Bleach (6.7 ppbv), and Ecolab Peroxide Multi Surface Cleaner and Disinfectant (8.3 ppbv).⁶ The VOCs studied decayed to background concentrations 1 h after application.⁶

We specifically tested products with active ingredients recommended for use against the SARS-CoV-2 virus in rooms of various types, both office and residential, although they have broader use as name brand disinfection products.³ The resulting VOC measurements may be useful in exposure estimates for risk calculations. One similar study by Lin et al. found total VOCs to be ${57\mathrm{mg}/\mathrm{m}}^3$ after cleaning in a U.S. hotel, with methylene chloride measured at concentrations of ${28\mathrm{mg}/\mathrm{m}}^3$ (7 ppbv) and chloroform at concentrations of ${4\mathrm{mg}/\mathrm{m}}^3$ (0.8 ppbv).⁹ In addition, Lou et al.¹⁰ studied disinfection by-products produced during the use of hypochlorite to mop floors in 40 indoor spaces in China during the COVID-19 pandemic. Median chloroform concentration was ${34\mathrm{mg}/\mathrm{m}}^3$ (8 ppbv) for a ${100\text{-}\text{\hspace{0.17em}to\hspace{0.17em}}200\text{-mg}/\mathrm{m}}^3$ application of hypochlorite solution.¹⁰ By comparison, our study found 5 ppbv chloroform, on average, from the use of Clorox Clean-Up Cleaner+Bleach Original and higher ranges of total VOCs.⁶

Of the disinfectants studied, Clorox Clean-Up Cleaner+Bleach Original contributed the highest concentrations of VOCs to indoor air, especially chloroform, which accounted for 48% of total VOCs. Although the concentrations of chloroform measured were lower than the STEL of 2 ppmv,⁸ repeated exposure of lower levels may contribute to health risk via inhalation.⁷ Ecolab Peroxide Multi Surface Cleaner and Disinfectant produced the lowest measured total VOC concentrations, whereas LabChem Reagent Grade Isopropyl Alcohol produced the highest. Detected isopropanol levels in the former product were still below the permissible exposure level set by the U.S. Occupational Safety and Health Administration.⁸ Lysol Power Bathroom Cleaner emitted a wide variety of VOCs, mostly ethanol and fragrant VOCs, such as limonene. Diluted Clorox Regular Bleach produced lower concentrations of emissions than the Clorox Clean-Up Cleaner+Bleach Original, which shared the same active ingredient, hypochlorite. Options to reduce VOC exposures are to use products containing hydrogen peroxide, nonscented products, maintain proper ventilation, open doors or windows, and leave the room for an hour. Although we observed great variability among disinfectants and indoor space types, our study shows many VOCs are indeed present during usage, and further investigation should be conducted on potential health risks.