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Environ Eng Res > Volume 29(1); 2024 > Article
Park, Yun, Yoon, Lee, and Zoh: Suspect and non-target screening of chemicals in household cleaning products, and their toxicity assessment

Abstract

In this study, 31 household spray-type cleaning products from 10 categories were examined to identify the substances contained in these products and evaluate their resulting toxicities. After substance detection via LC-QTOF-MS, suspect and non-target screenings were performed using UNIFI software. A total of 48 substances were identified during suspect screening. Among them, surfactant (freq. 22/31(71.0%)), plasticizer (freq. 23/31(74.2%)), antioxidant (freq. 20/31(64.5%)) were detected with high frequencies. Among the 48 compounds, tributyl citrate acetate was the most frequently detected (frequency 13/31, 41.9%). In addition, 51 substances were identified via non-target analysis. Among them, oleamide, a type of surfactant, showed a high frequency of detection (22/31(71.0%)). The toxicities of the 98 substances (suspect: 47 (except for confidence level 5) and non-target: 51) identified were evaluated using the European Chemicals Agency (ECHA) database and Toxtree. Among them, 20 substances were classified as a substance of caution. The risk assessment for 3 substances identified with references standards was also performed. The suspect and non-target screening technique proved to be a useful method that can be applied when there are many non-specific chemicals and their components in the consumer products are not well known.

Graphical Abstract

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1. Introduction

Numerous chemicals are used daily, especially those found in consumer products. As the use of consumer products comprising numerous chemicals increases, the risk of human exposure to these chemicals increases as they can be transmitted to humans via various routes [1]. However, studies on the potential exposure of chemicals to humans from daily consumer products are lacking due to the following reasons. First, due to the ingredient disclosure requirement in many countries, consumer products may list numerous ingredients [2]. However, most consumer products only list general ingredients or do not list complete ingredients. Consequently, the information provided on product labels and material safety data sheets (MSDSs) is insufficient for fully identify product constituents and their potential health effects due to exposure [3]. Secondly, consumers may be simultaneously exposed to multiple substances in various products. For example, substances, such as benzophenone-3, bisphenol-A, phthalates, and polybrominated diphenyl ethers, can have synergetic effects on the human body, even when the chemicals are individually present at safe levels [4, 5], Thirdly, once commercialized, it is difficult to stop the use of chemicals, even if it is known to have adverse health effects. For example, polyhexamethylene guanidine (PHMG), a humidifier disinfectant associated with pulmonary fibrosis outbreaks in South Korea, was mainly used as a deterrent to clean carpets and swimming pools. PHMG included methylisothiazolinone (MIT) and benzisothiazolinone (BIT), which are used as disinfectants. Notably, the harmful effect of these chemicals on the human body was underestimated at the time of the outbreaks [4, 6].
To reduce the risk of exposure of substances contained in household consumer products and their adverse effects on humans, first, the substances in the products should be identified. Although most previous studies have analyzed chemicals using targeted analytical methods, the studies that analyze undisclosed or unintended components of consumer products and identify chemicals other than target compounds are lacking.
Owing to the recent development of advanced monitoring methods, the detection of known chemical classes and classes that were not previously targeted for detection has become a prominent topic in environmental research [7]. In particular, high-resolution mass spectrometry (HR-MS) has been used to identify substances in the products, screen by-products, and unintended chemicals, and assess the indicated substance information provided for the products [8]. Advances in high-resolution mass spectrometry can not only enable the detection of targeted compounds, but also identify expected (suspect) compounds using existing databases, libraries, or software matching algorithms. These advances have made it possible to closely examine HR-MS spectra to identify previously unknown compounds (off-targets) [7, 9, 10]. Gas chromatography high-resolution mass (GC-HRMS) has been used primarily for chemical analysis, especially semi-volatile organic compounds (SVOC), in products using suspect and non-suspect screening [8, 11, 12]. However, there are not many studies using liquid chromatography (LC-HRMS) [13].
Therefore, in this study, 31 household cleaning products from 10 categories (bathroom/toilet, kitchen, glass, metal, air conditioner, automobile, carpet, multipurpose, floor, and bowling ball) were examined to identify the chemicals in the products and evaluate their toxicities. To identify the substances in the products, suspect and non-target screening methods via liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) was adopted using the UNIFI platform (Waters, Milford, MA USA). To estimate the toxicity of the identified substances, the ToxTree open-source program tool (http://toxtree.sourceforge.net/index.html) and the European Chemicals Agency (ECHA) database [15] were used to estimate the toxicities of identified substances. Finally, the risk assessment was performed for substances identified with reference standards.

2. Materials and Methods

2.1. Standards and Reagents

Methyl tertiary butyl ether (MTBE) was purchased from Sigma-Aldrich (St. Louis, MO, USA) for sample preparation. Herein, 0.1% formic acid (Sigma-Aldrich, ACS grade) in methanol (Fisher Chemicals, LC-MS grade, Loughborough, UK) and 0.1% formic acid in acetonitrile (Honeywell, HPLC grade, Morristown, USA) was used as the mobile phase for liquid chromatography (LC). Reference standards containing tributyl citrate acetate (C20H34O8), glyceryl monostearate (C21H42O4) and 2-(2-butoxyethoxy)ethyl acetate (C10H20O4) were purchased from Sigma-Aldrich. Stock solutions were prepared with water from a Milli-Q water system (R = 18.2 MΩ/cm, Millipore, St. Louis, USA).

2.2. Selected Samples

Of the products governed under the Chemical Product Safety Act of Korea [14], 31 cleaning products that can be purchased online were selected. The products were classified into 10 groups according to their intended use: bathroom/toilet (n=8), kitchen (n=6), glass (n=5), metal (n=2), automobile (n=2), air conditioner (n=2), carpet (n=2), multipurpose (n=2), floor (n=1), and bowling ball (n=1). Detailed information is provided in Table S1 (Supporting Information).

2.3. Sample Preparation

All samples were pretreated using the method described by Guo and Kannan [15] with minor modifications. Since it is difficult to detect all the substances in the consumer products, this study focused on hydrophobic substances with high bioaccumulation [16,17], to extract mainly hydrophobic substances, 0.2 g of each sample was added to 5 mL of MTBE and mixed evenly. The sample was then shaken in an orbital shaker for 30 min and centrifuged at 3500 rpm for 20 min to obtain 5 mL of the supernatant. After this process was repeated, 10 mL of the extract was obtained, purged with nitrogen (99% purity), then concentrated to 1 mL, and finally filtered with a 0.45 μm membrane filter for instrument analysis.

2.4. Sample Analysis

Ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS; Acquity UPLC System coupled with a SYNAPT G2-Si mass spectrometer, Waters, Milford, MA, USA) with an Acquity UPLC BEH C18 column (100 mm × 2.1 mm, 1.7 μM, Waters) was used for suspect and non-target screening. Mobile phases A (0.1% formic acid in deionized water) and B (0.1% formic acid in acetonitrile) for positive mode, and (A) deionized water and (B) acetonitrile for negative mode were used according to the following gradient mode program at a flow rate of 0.3 mL/min: 0–16 min, 10–99% B; 16–21 min, 99% B; 21–24 min, 99–10% B. The auto-sampler was maintained at 15 °C and the injection volume was 2 μL. MS analysis was performed with electrospray ionization (ESI) in the m/z range of 50–1200; detailed information is provided in Table S2 (Supporting Information). A lock spray source (leucine enkephalin positive: 556.2771 Da, negative: 554.2615 Da) was used as the reference lock mass. All samples were run in LC-QTOF-MSe continuum mode. Triplicate injections were performed for all samples in positive and negative modes. To prevent contamination of the analytical instrument, LC and TOF-MS were cleaned before analysis.

2.5. Data Screening and Identification

Data obtained after instrument analysis were screened using the UNIFI platform (Waters, Milford, MA USA) (Fig. 1). If the same substance was detected both in the sample and a blank, any response below three times the blank response (instrument detection limit) was removed. In addition, all chromatograms were manually screened, and the peaks were classified by manually evaluating their fit. The substance identification workflow for the suspect and non-target screening is shown in Fig. 2, and the confidence level of the identified substances was determined using the method described by Schymanski et al. [18] (Table 1).

2.5.1. Suspect screening process

All samples were filtered using the UNIFI platform to compare the mass spectra, retention times, molecular formulas, and structures of a library (Waters, Extractables, and Leachables HRMS Library) containing 581 substances (Table S3). Compound identification was based on mass error (< ±10 ppm), chromatographic width ratio (< 1.5), response (> 50), theoretical fragments found (> 0), and isotope match intensity root-mean-square (RMS) percentage (< 20) (Fig. 2). The mass error is usually set to 5 ppm or less, but in this study, the range was set to ±10 ppm because even the peaks of which the mass error exceeding ±5 ppm have the isotope match root-mean-square (RMS) value of 20 or less (the recommended value by Waters), and the shapes of those chromatograms were sharp.

2.5.2. Non-target screening process

The substances that were not identified during suspect screening were subjected to non-target screening via the following four steps (Fig. 2) [19]; First, after instrument analysis, the number of features was appropriately reduced with the filtering process by the chromatographic width ratio (1.5) and response (1,000); Secondly, to determine the empirical formula for substances that were not identified after the filter step, i-FIT™, which is the UNIFI algorithm system, was used to obtain the i-FIT confidence percentage, which is a potential molecular formula; Thirdly, possible names and structures associated with the empirical formula or exact mass were searched using online libraries, such as ChemSpider Library, PubChem, and Thomson Pharma libraries. Finally, the UNIFI program was used to identify a possible structural candidate by comparing the experimental spectrum of an unidentified compound obtained at high energy with its theoretically predicted fragments [2023]. The candidate structures were then ranked based on the relative intensity of the fragments, the number of matched fragment ions, and the number of citations in the literatures. In this step, the number of match fragmentations was set to > 5, the intensity was set to > 50%, and the number of citations was set to > 10.

2.6. Risk Assessment

Among the substances identified with the standard product in this study, risk assessment was performed. The estimated daily intake (EDI) levels via dermal contact of cleaning products were determined using Eq. (1):
(1)
EDI (μg/kg bw/d)=C (ng/g)×A (g/time)×F(time/d)Body weight (kg)×abs
where C is a chemical's concentration in cleaning products (ng/ml, ppb), A is the amount of cleaning products consumed per time (g/time), F the frequency of use (time/day), and abs. the absorption rate [24]. Table S4 summarizes the values assigned for each parameter in the equation [25].
The potential health risks of exposure to chemicals from the use of cleaning products were evaluated using a hazard quotient (HQ) (Eq. (2)) [26]:
(2)
HQ=EDIRfD
where RfD represents the reference dose. The RfD value was calculated using the NOAEL value and the uncertainty factor value (Table S5) [2729].

3. Results & Discussions

3.1. Suspect Screening

From suspect screening of 31 cleaning products, 48 chemicals were identified using LC-QTOF-MS (Table 2), of which 40 were from positive and 8 from negative modes. The sample information with identified chemicals is provided in Supporting Information (Table S6-1: positive and Table S6-2: negative). Based on their usage, 48 substances were classified as follows: surfactant (n=10) (frequency: 22/31(71.0%)), plasticizer (n=6) (freq. 22/31(74.2%)), antioxidant (n=4) (freq. 20/31(64.5%)), UV absorber (n=3) (freq. 4/31(12.9%)), fragrance (n=2) (freq. 2/31(6.5%)), foam boosting substance (n=2) (freq. 4/31(12.9%)), solvent (n=2) (freq. 10/31(32.3%)), viscosity controlling substance (n=2) (freq. 9/31(29.0%)), buffers (n=1) (freq. 1/31(3.2%)), other plastic additives (n=1) (freq. 1/31(3.2%)), and unknown (n=15). The detailed identified substances were discussed as follows.

3.1.1. Plasticizer category

Plasticizers account for approximately one-third of the global plastic additives market in terms of consumption [30], and have been scrutinized for their contribution to environmental and health related problems [31, 32]. Many plasticizers are endocrine-disrupting chemicals (EDCs) that can adversely affect reproductive development [33]. In particular, di-(2-ethylhexyl) phthalate (DEHP) and other phthalates such as dibutyl phthalate (DBP), and benzyl butyl phthalate (BBP) have been registered as candidates of high concern by the Registration, Evaluation, Authorization, and Restriction of Chemicals (REACH). As a result, many countries have various regulations regarding plasticizers as ingredients in consumer products [34].
In this study, the most frequently identified substance from the suspect screening of the cleaning products is tributyl citrate acetate (CAS No. 77-90-7, freq. 13/31(41.9%)) (Fig. 3). Tributyl citrate acetate is known as a plasticizer and has a specific migration limit of 60 mg/kg by the European Food Safety Authority [35]. This chemical is mainly used in surface treatment, washing, and cleaning products [36]. Citrates-based plasticizers are reported to be relatively safer than conventional phthalate plasticizers in terms of reproductive, developmental, acute, and genotoxicity, but there is insufficient information on their endocrine disrupting properties and various toxic endpoints, so in vivo and in vitro studies are needed [37, 38]. Malnes et al. measured tributyl citrate acetate at a concentration of 6.3 ng/L (max. 29.0 ng/L) at 15 sewage treatment plants (STPs) in Sweden, with a detection frequency of 100% [39]. Lee et al. also reported that tributyl citrate acetate was detected in wastewater treatment plants (WWTPs) in South Korea at concentrations of 29–19000 ng/g and with frequencies of 73–100% [40]. The higher detection frequency (41.9%) of tributyl citrate acetate in this study can be explained by its universal use in cleaning products as a plasticizer.
Another identified chemical by suspect screening is luperox 101 (CAS No. 78-63-7, freq. 10/31(32.3%)) which was detected primarily in bathroom/toilet products (Fig. S1). Many household chemicals use polypropylene as packaging [41], and luperox 101 is used as a viscosity modifier for polypropylene [42]. The high detection frequency of Luperox 101 is most likely due to the frequent use of polypropylene product containers and the elution of Luperox 101 from the container. Luperox 101 has been shown to be cytotoxic and corrosive to the skin [43].

3.1.2. Surfactant category

Owing to their physicochemical properties, surfactants have broad applications in household cleaning products, including laundry detergents, surface cleansers, and personal care products [44]. The interaction of surfactants with the skin can produce clinical manifestations, including skin dryness, changes in skin texture, modification of permeability properties, and inflammation [45].
Among the surfactants identified in the household cleaning product samples by suspect screening, n,n-bis(2-hydroxyethyl)dodecanamide (CAS No. 120-40-1, freq. 1/31(3.2%)) (Fig. S2) is classified as List 7 Substances for which some toxicological data exist, but for which an acceptable daily intake (ADI) or a Tolerable Daily Intakes (TDI) could not be established (EC, 1999) [46]. It is reported that n,n-bis(2-hydroxyethyl)dodecanamide is widely used in detergents for dishwashing, washing machine products for cleaning fabrics, and polish metal surface cleaners [47].
Another substance identified in the household cleaning product samples, tetraethylene glycol (CAS No. 112-60-7, freq. 1/31(3.2%)), is used as a surfactant in surface treatment, and washing or cleaning products [48]. Tetraethylene glycol is known as a mild skin irritant and can affect the central nervous system, liver, kidney, and reproductive function of humans after long periods of exposure [49].
Another surfactant, octoxynol 7 (CAS No. 2497-59-8, frequency 4/31 (12.9%)), has been reported to induce estrogen both in vivo and in vitro because it mimics the effect of estradiol [50, 51]. In addition, among the identified surfactants, hexadecanol (CAS No. 36653-82-4, freq. 15/31 (48.4%)) has little toxicity by Toxtree and ECHA, despite its high detection frequency.

3.1.3. Antioxidant category

Synthetic antioxidants are a group of critical anthropogenic chemicals broadly used in foodstuffs, personal care products, plastics, lubricants, and rubber products for protection from oxidative degradation [5255]. According to recent studies, some antioxidants can be present in human urine, serum, plasma, breast milk, and the placenta, indicating human exposure [5660].
Among these antioxidant categories, 2,6-di-tert-butyl-4-ethylphenol (CAS No. 4130-42-1, freq. 1/31(3.2%)) (Fig. S3), was identified in the samples examined herein. This substance is known as an antioxidant and stabilizer in polymers employed in food manufacturing [61], and is widely used to prevent free-radical-mediated oxidation in fluids (e.g., fuels and oils) and other materials [62]. It is reported that 2,6-di-tert-butyl-4-ethylphenol not only hinders the survival and reproduction of aquatic organisms, but also endangers human health [63, 64].
Bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphate (CAS number 97994-11-1, freq. 18/31(58.1%)), one of the organophosphate esters (OPEs), is a family of anthropogenic additives with high production and application volumes, and widely used in many industrial and household products [65]. OPEs are often observed in human serum and urine, and there is growing interest in the identification of OPE in the environment due to its endocrine-disrupting potential toxicity [6668].

3.1.4. Fragrance category

Studies have shown that a variety of household cleaners include fragrances with unique scents, and fragrance products, including air fresheners, deodorants, cleaning products, laundry detergents, fabric softeners, essential oils, scented candles, soaps, personal care products, perfumes, and hand sanitizers [69, 70]. Owing to increased usage and exposure, clinical cases of health conditions that are caused, triggered, and exacerbated by fragrance products are increasing.
In the fragrance category, diethyl sebacate (CAS No. 110-40-7, freq. 1/31(3.2%)) was identified in kitchen cleaner samples (Sample No. 10) (Fig. S4). It is widely used as a food flavoring agent and is also used in perfumes [71]. It is reported that diethyl sebacate can cause allergic contact dermatitis [72].

3.1.5. UV absorber

One of the UV absorbers detected in this study, octabenzone (CAS No. 1843-05-6, freq. 1/31(3.2%)), is frequently used in cleaning products and household care [73]. Octabenzone is not readily biodegradable and is potentially persistent [74]. It is also reported that octabenzone causes a concentration- and time-dependent loss of cell viability accompanied by a depletion of intracellular adenosine triphosphate (ATP) in rat hepatocytes [74]. Another substance identified in this study was tinuvin 144 (CAS No. 63843-89-0, freq. 2/31(6.5%)) (Fig. S5). Tinuvin 144, a type of polyurethane as a UV absorber [75], was detected in the sample No. 12 and No. 26. This chemical is mainly used in adhesives, sealants, coatings and paints, and paint removers [74], can be detected as polyurethane foam in various cleaning agents [7678]. Of note, tinuvin 144 is a hindered amine that is toxic to the immune system, liver, blood, and male reproductive system [79].

3.2. Non-target Screening

Substances that are not identified in the MS library after instrument analysis can be categorized as substances through a non-target screening process. Through the non-target screening process, a total of 51 substances were identified in the positive mode from the samples, and no substances were identified in the negative mode (Table 3). 51 substances were classified based on their usage categories as follows: surfactant (n=6) (frequency: 28/31(90.3%)), emulsifier (n=4) (freq. 2/31(6.5%)), fragrance (n=2) (freq. 2/31(6.5%)), PFAS (n=4) (freq. 3/31(9.7%)), %)), antistatic agent (n=4) (freq. 8/31(25.8%)),viscosity controlling substance (n=1) (freq. 1/31(3.2%)), and unknown (n=30). Sample information with substances identified is provided in Table S7.
Among 51 substances, oleamide (CAS No. 301-02-0, freq. 22/31(71.0%)) (Fig. S6) was the most frequently detected substance via non-target screening in this study. Oleamide, is one of the surfactant, has a variety of industrial uses including as a slip agent, a lubricant, and a corrosion inhibitor [80]. Oleamide is known to be leached out of polypropylene plastics [81]. It is reported that, in rats, the oral LD50 of undiluted oleamide DEA was 12.4 mL/kg [82]. Next, as one of the emulsifiers, myreth-3 (CAS No. 26826-30-2, freq. 1/31 (3.2%)) (Fig. S7), was detected in kitchen products. The emulsifier is a type of surfactant and is a substance that helps immiscible liquids, such as water and oil, mix well [83]. In addition, as one of the PFASs, 4,4,4-trifluorobutanal (CAS number 406-87-1, frequency 1/31 (3.2%)) (Fig. S8) was detected in bathroom/toilet products. According to Gluge et al., various PFAS are detected in cleaning products [84]. Also, palmitamidopropyl dimethylamine (CAS No. 39669-97-1, freq. 3/31 (9.7%)) (Fig. S9) detected in this study is one of the antistatic agents. Cleaning products are balanced blends of cleaning and surface care ingredients that create a “care film” that protects from chemical breakdown or abrasion to maintain and improve surfaces, and in some cases may have antistatic effects [85].

3.3. Characterization of Identified Compounds from the Suspect and Non-target Screening

All substances identified in the suspect and non-target screening are summarized in Table 2 (suspect screening) and Table 3 (non-target screening), along with their assigned confidence levels. Among the identified 99 substances, Confidence level 1 (confirmed structure) was assigned if the substance was identifiable based on a comparison with the reference standard among the screened substances. Information on the confidence level 1 substances compared to the reference standard is shown in Fig. 3, Fig. S10, and S11. 3 substances (tributyl citrate acetate, glyceryl monostearate and 2-(2-butoxyethoxy)ethyl acetate) were identified at a confidence level 1. Tributyl citrate acetate (retention time: 12.94 min) (Fig. 3), which is used as a plasticizer, was also detected in 13 of the 31 samples. Glyceryl monostearate (retention time: 15.43 min) (Fig. S10) is typically used as a surfactant and was detected in 5 of the 31 samples. 2-(2-Butoxyethoxy)ethyl acetate (RT: 6.75 min) (Fig. S11) is typically used as a solvent and was detected in 9 of the 31 samples.
Next, 45 substances, where no reference standards were available, were assigned to Confidence level 2 (probable structure) by available library spectra and the characteristic fragments during suspect screening (Table 2). In addition, 45 substances identified by non-target screening, although not conclusive MS fragments were identified, were assigned to Confidence level 3 (tentative candidates) (Table 3). Also, the chemical structures of 5 substances were confirmed based on the fragment information, but Confidence level 4 (unequivocal molecular formula) was assigned because insufficient evidence exists to propose possible structures (Table 3). Finally, one substance, which was identified as hexadecylamine (CAS No. 143-27-1, RT: 9.84 min) through library matching in the suspect-screening process, was assigned confidence level 5 (exact mass (m/z)). However, it was confirmed as a false positive because the retention time was different from the standard (RT: 10.83 min) (Fig. 4).
To provide a higher confidence level of data, it is believed that more standards should be purchased and compared to the identified substances.

3.4. Toxicity Assessment

ECHA database can provide not only toxicity information but also substance regulatory information. The ECHA database was used to evaluate the toxicity of 98 substances identified in this study (suspect: 47 (except for confidence level 5) and non-target: 51). Among them, 26 identified substances were not included in the ECHA database, 35 substances were included in the ECHA database, but with no toxicity information. 31 substances were classified as “substances predicted as likely to meet the criteria for carcinogenicity, mutagenicity, or reproductive toxicity” in the ECHA database. Finally, 6 substances were included in the ECHA database, and have toxicities (Table S8), but do not meet the criteria for carcinogenicity, mutagenicity, or reproductive toxicity. Among 6 substances, octoxynol 7 (CAS No. 2497-59-8, freq. 4/31(12.9%)) is classified as an EDC, and tributyl citrate (CAS No. 77-94-1, freq. 3/31(9.7%)) has been listed under evaluation for EDCs.
For the assessment of the potential toxicity of the substances identified in the samples, Toxtree, a free QSAR tool, was used to determine the Cramer class of a chemical and estimate its relative toxic hazard [86]. In Toxtree, risk assessment for most human health effects is based on the threshold of a toxicological effect, usually derived from animal experiments. Toxtree was found to be a useful tool in facilitating the systematic evaluation of compounds through the Cramer scheme [87].
The Cramer classification scheme (decision tree) is the best-known approach for estimating the threshold of toxicity concern (TTC) of a chemical based on its chemical structure [88]. TTC concept can provide a means of waiving testing based on knowledge of exposure limits. This scheme was encoded into a software program called Toxtree, specifically commissioned by the European Chemicals Bureau (ECB). There are three Cramer classes, with Class 3 representing the most severe toxicity risk, and Class 3 compounds assigned the lowest TTC values. The classification criteria are listed in Table S9. The rule classified 58 substances as “highly toxic (Class 3)” and 27 substances as “low toxicity (Class 1)” based on their chemical structure. If the substances were found to be toxic in both evaluations (Toxtree: Cramer rules Class 3, ECHA: “substances predicted as likely to meet the criteria for carcinogenicity, mutagenicity, or reproductive toxicity”), they were classified as cautious substances.
Based on ECHA database and Toxtree tool, 20 substances (bisphenol A (2,3-dihydroxypropyl) glycidyl ether (BADGE-glycidyl), bis(oxiran-2-ylmethyl) cyclohex-4-ene-1,2-dicarboxylate, methyl 1,2,2,6,6-pentamethyl-4-piperidinyl sebacate, myristamide, myricetin, pentaerythritol triallyl ether, linalool oxide, (.+−.)-limonene, (Z)-N-Isopropyl-9-octadecenamide, (9Z)-N-methyl-9-octadecenamide, diethyl caprylamide, diisopropyl methylphosphonate, elaidamide, isostearamidopropyl dimethylamine, lauramide, methyl(trifluoromethyl)dioxirane, oleamide, palmitamidopropyl dimethylamine, Rionox MD-697(Naugard® XL-1), Succinylsulfathiazole) were classified as a substance of caution. These substances were classified as cautionary substances in both toxicity assessment tools (ECHA database and Toxtree) with a high level of toxicity (Table S8). Among 20 substances, myricetin [89], pentaerythritol triallyl ether [90], linalool oxide [91], (.+−.)-limonene [92], and diisopropyl methylphosphonate [92] are related to the consumer products based on literature reviews.

3.5. Risk Assessment

To assess the potential risk by using cleaning products, we selected three substances (tributyl citrate acetate, glyceryl monostearate and 2-(2-butoxyethoxy)ethyl acetate; confidence level 1) which were identified with analytical standards, and the concentration of each compound was summarized in Table S10. The concentration of each substance was compared by comparing the response of each sample with the response of the standard calculated from LC-QTOF-MS analysis. Exposure risk evaluation was conducted for four product groups (bathroom/toilet, kitchen, glass, and multipurpose) for which dermal exposure coefficients could be obtained.
When the EDIs were evaluated by product group, they ranged from 1.71 × 10−4 to 1.08 × 10−3 (μg/kg bw/day) (Table 4). This is because the products are of the same type (spray), the amount of spray per application is similar, and the difference in concentration levels of each substance detected in the products is not significant. The HQ values for the substances within each product group were less than 1 (from 9.40 × 10−8 to 2.28 × 10−6 (μg/kg bw/day)), indicating that the potential hazards of these substances in each product group are low (Table 4).
However, since we only conducted the risk assessment using three substances having reference standards, and we did not perform the same approach on 20 substances classified as a substance of caution by the ECHA database and Toxtree tool. This is the limitation of this study. Future study is needed for the accurate risk assessment by comparing these 20 substances with reference standards to estimate the actual risk by exposing the substances in household cleaning products.

4. Conclusions

Among the cleaning products frequently used in daily life, 31 spray type products were subjected to suspect and non-target screening by LC-QTOF-MS to identify the substances in the products. Based on the suspect screening process, plasticizers (freq. 23/31(74.2%)), surfactants (freq. 22/31(71.0%)), and antioxidants (freq. 20/31(64.5%)) were detected with high frequencies. From the non-target analysis, oleamide, a type of surfactant, was identified with the highest frequency of 22/31(71%). From toxicity evaluation using the ECHA database and Toxtree, among the 98 identified substances, 31 substances were classified as “substances predicted as likely to meet criteria for carcinogenicity, mutagenicity, or reproductive toxicity,” and 58 substances were classified as “highly toxic (Class 3).” 20 substances were classified as a substance of caution. Finally, a risk assessment was conducted for three substances identified with reference standards.
Our results indicate that household cleaning products contain various substances which can be toxic, in addition to listed general ingredients on the labels. Therefore, continuous monitoring of products containing these substances in consumer products is needed as future studies. A more complete risk assessment associated with exposure from the use of household cleaning products containing these substances is also needed by examining concentrations with more reference standards.

Supplementary Information

Acknowledgments

This work was supported by Korea Environment Industry & Technology Institute (KEITI) through Technology Development Project for Safety Management of Household Chemical Products Program (or Project), funded by Korea Ministry of Environment (MOE) (2021002970003, 1485019148(NTIS))

Notes

Conflict-of-Interest statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Author Contributions

J.H.P (Ph.D. candidate) conducted the experiments and data processing and wrote the manuscript. H.J.Y. (Master candidate) conducted the experiments. C.Y. (Professor) concepted, received the funding, and supervised the research. K.L. (Professor) concepted and supervised the research. K.D.Z (Professor) conceived, supervised the research, wrote and revised the manuscript.

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Fig. 1
UNIFI platform interface used in this study (ex. Luperox 101: CAS No. 78-63-7) (upper left: Total Ion Chromatogram (TIC) and lower left: extracted Ion Chromatogram (IC) for the selected component)
/upload/thumbnails/eer-2023-123f1.gif
Fig. 2
Workflow followed during the compounds screening
/upload/thumbnails/eer-2023-123f2.gif
Fig. 3
Comparison of the spectrum (bottom) between the identified substance (sample No. 20) and the reference standard (top) (Tributyl citrate acetate, CAS No. 77-90-7)
/upload/thumbnails/eer-2023-123f3.gif
Fig. 4
False positive peak identified as hexadecylamine in the suspected screening by the Waters library (Reference standard (top, RT: 10.83) vs. No. 31 Sample (bottom, RT: 9.84 min))
/upload/thumbnails/eer-2023-123f4.gif
Table 1
Proposed identification confidence levels [18]
Level 1 Confirmed structure by reference standard
Level 2 Probable structure by library spectrum match & diagnostic evidence
Level 3 Tentative candidate(s) - structure, substituent, class
Level 4 Unequivocal molecular formula
Level 5 Exact mass of interest
Table 2
Substances identified in the suspect screening
Chemical group Component name Formula CAS No. Observed m/z Mass error (ppm) Observed RT (min) Isotope match intensity RMS percent Response Theoretical Fragments Found Adducts Confidence level Frequency Identified sample group
plasticizer Luperox 101 C16H34O4 78-63-7 291.2514 −5.4 11.24 11.89 2109 9 +H, +Na 2 10/31 bathroom/toilet (5), glass (2). automobile (1), air conditioner (1), carpet (1)
plasticizer Mesamoll C21H36O3S 20755-22-0 369.2463 1.3 12.88 14.98 351 11 +H 2 2/31 kitchen (1), carpet (1)
plasticizer Tributyl citrate C18H32O7 77-94-1 383.202 −5.3 10.84 17.26 16045 14 +Na, +H 2 4/31 bathroom/toilet (2), kitchen (2)
plasticizer *Tributyl citrate acetate C20H34O8 77-90-7 425.2125 −4.9 12.93 13.66 1857 6 +Na, +H 1 13/31 bathroom/toilet (1), kitchen (2), glass (3), metal (2), automobile (1), air conditioner (1), carpet (1), multipurpose (2)
plasticizer Tris(2-butoxyethyl) phosphate C18H39O7P 78-51-3 399.2498 −2.2 12.87 18.3 152 9 +H 2 1/31 bathroom/toilet (1)
plasticizer 2,2,4-Trimethyl-1,3-pentanediol diisobutyrate C16H30O4 6846-50-0 331.2152 7.8 7.B7 17.4 157 5 +HCOO 2 1/31 bathroom/toilet (1)
surfactant Bis(2-hydroxyethyl) dodecylamine C16H35NO2 1541-67-9 296.2546 −4.6 11.24 16.68 159 4 +Na 2 1/31 glass (1)
surfactant Ethylene glycol monoricinoleate C20H38O4 106-17-2 387.274 −3.1 11.5 10.65 1939 3 +HCOO 2 1/31 kitchen (1)
surfactant *Glyceryl monostearate C21H42O4 123-94-4 381.2993 4.6 15.64 10.09 1218481 26 +Na 1 6/31 bathroom/toilet (1), kitchen (2), glass (1), metal (1), carpet (1)
surfactant Hexadecanol C16H34O 36653-82-4 265.2505 1.3 14.37 9.21 8805 4 +Na 2 15/31 bathroom/toilet (2), kitchen (2), glass (4), metal (1), automobile (1), air conditioner (1), carpet (2), multipurpose (1), bowling ball (1)
surfactant N,N-Bis(2-hydroxyethyl)dodecanamide C16H33NO3 120-40-1 288.2509 −8.2 8.06 17.36 19518 8 +H 2 1/31 glass (1)
surfactant Octoxynol 7 C28H50O8 2497-59-8 537.338 −3.3 11.65 12.21 5352 14 +Na, +H 2 4/31 bathroom/toilet (2), air conditioner (1), bowling ball (1)
surfactant Palmitic acid C16H32O2 57-10-3 279.2295 0.2 10.91 4.06 664 9 +Na 2 2/31 bathroom/toilet (1), metal (1)
surfactant Stearic acid C18H36O2 57-11-4 307.2604 −1 15.62 13.68 112 14 +Na 2 1/31 air conditioner (1)
surfactant Tetraethylene glycol C8H18O5 112-60-7 195.1209 −9 16.54 10.97 1964 4 +H 2 1/31 bathroom/toilet (1)
surfactant Trihexyl acetylcitrate C26H46O8 24817-92-3 487.3222 −8.8 12.21 18.16 4439 19 +H 2 1/31 bathroom/toilet (1)
antioxidant Cyanox® LTDP C30H58O4S 123-28-4 537.3947 −0.2 11.11 16.59 425 7 +Na 2 2/31 bathroom/toilet (2)
antioxidant Myricetin C15H10O8 529-44-2 319.0464 5 2.6 10 1279 4 +H 2 1/31 air conditioner (1)
antioxidant Bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphate C33H50O8P2 97994-11-1 637.3045 −1.4 14.35 15.39 5383 7 +H, +Na 2 18/31 bathroom/toilet (5), kitchen (3), glass (3), automobile (2), air conditioner (2), carpet (1), multipurpose (1), floor (1)
antioxidant 2, 6-Di-tert-butyl-4-ethylphenol C16H26O 4130-42-1 257.1875 −0.4 10.97 10.85 3562 5 +Na 2 1/31 metal (1)
fragrance Diethyl sebacate C14H26O4 110-40-7 281.1697 −9.3 14.05 11.42 109 6 +Na 2 1/31 kitchen (1)
fragrance Linalool oxide C10H18O2 60047-17-8 169.1223 −6.4 6.37 5.34 348 2 −H 2 1/31 air conditioner (1)
UV absorber Methyl 1,2,2,6,6-pentamethyl-4-piperidinvl sebacate C21H39NO4 82919-37-7 370.2985 9.1 13.79 13.04 1303 11 +H 2 1/31 glass (1)
UV absorber Octabenzone C21H26O3 1843-05-6 325.1841 9.7 12.43 11.32 661681 5 −H 2 1/31 glass (1)
UV absorber Tinuvin 144 C42H72N2O5 63843-89-0 685.5524 1.5 9.21 13.84 298 5 +H 2 2/31 kitchen (1), carpet (1)
solvent 1,4-Butanediol diglycidyl ether C10H18O4 2425-79-8 201.1121 −5.6 7.88 14.92 5599 3 −H 2 1/31 bathroom/toilet (1)
solvent *2-(2-Butoxyethoxy)ethyl acetate C10H20O4 124-17-4 227.1249 −2 6.73 10.81 202 0 +Na 1 9/31 bathroom/toilet (1), kitchen (2), glass (2), metal (2), air conditioner (1), carpet (1)
viscosity controlling Azacyclotridecan-2-one C12H23NO 947-04-6 198.1835 −8.6 14.39 10.84 124 9 +H 2 1/31 air conditioner (1)
viscosity controlling Dimethyldibenzylidene sorbitol C24H30O6 135861-56-2 415.2105 −2.4 9.04 17.83 15684 10 +H, +Na 2 8/31 bathroom/toilet (1), kitchen (2), glass (3), metal (1), automobile (1)
foam boosting N,N-Diethanololeamide C22H43NO3 93-83-4 370.3319 1 13.59 10.18 916109 10 +H, +Na 2 1/31 kitchen (1)
foam boosting Octadecanamide C18H37NO 124-26-5 284.2926 −7.6 15.66 16.52 10718 20 +H 2 3/31 glass (2), air conditioner (1)
buffering Quinic acid C7H12O6 77-85-2 215.052 −2.8 7.88 8.46 213 6 +Na 2 1/31 bathroom/toilet (1)
other plastic additive 3,9-Bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro [5.5]undecane C15H28O6 1455-42-1 327.1774 −1.4 8.28 11.68 114 7 +Na 2 2/31 bathroom/toilet (1), kitchen (1)
- Bisphenol A (2,3-dihydroxypropyl) glycidyl ether (BADGE-glycidyl) C21H26O5 78002-91-0 359.1845 −2.3 13.28 16.63 777 4 +H 2 2/31 bathroom/toilet (1), air conditioner (1)
- Bis(oxiran-2-ylmethyl) cyclohex-4-ene-1,2-dicarboxylate C14H18O6 21544-03-6 281.1052 7.5 7.08 14.5 172 2 −H 2 1/31 automobile (1)
- Methyl Nadie anhydride C10H10O3 25134-21-8 201.0507 −7.3 8.25 12.73 104 6 +Na 2 1/31 bathroom/toilet (1)
- Methyl Tetrahydrophthalic Anhydride C9H10O3 3425-80-6 189.0522 −0.3 9.51 12.77 285 10 +Na 2 1/31 multipurpose (1)
- Nonadecanoic acid(C19) C19H38O2 646-30-0 321.2761 −0.8 15.64 17.42 135 11 +Na 2 2/31 bathroom/toilet (1), multipurpose (1)
- Nonionhs208 C24H42O6 2315-64-2 449.2859 −3.2 11.39 8.61 579 4 +Na 2 3/31 bathroom/toilet (1), metal (1), bowling ball (1)
- Oxtoxynol-10 C34H62O11 2315-66-4 669.4165 −2.8 11.56 17.09 7101 28 +Na, +H 2 5/31 bathroom/toilet (2), metal (1), air conditioner (1), bowling ball (1)
- Pentaerythritol triallyl ether C14H24O4 1471-17-6 279.1558 −3 11.39 15.88 477 9 +Na 2 2/31 bathroom/toilet (2)
- 2-Benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone C23H30N2O2 119313-12-1 365.2226 −2.3 7.67 19.23 428197 5 −H 2 3/31 kitchen (1), multipurpose (1), floor (1)
- Rionox MD-697 (Naugard® XL-1) C40H60N2O8 70331-94-1 697.4386 −5.2 14.27 7.8 6643 9 +H +Na 2 1/31 bathroom/toilet (1)
- Succinylsulfathiazole C13H13N3O5S2 116-43-8 378.0207 4.8 5.63 11.92 135 12 +Na 2 2/31 bathroom/toilet (1), kitchen (1)
- 1,2,3-Trideoxy-4,6_5,7-bis-O-((4-propyl phenyl)methylene)-nonitol (NX 8000) C29H40O6 882073-43-0 485.2943 9.3 12.93 9.5 363 24 +H 2 3/31 bathroom/toilet (2), kitchen (1)
- 1,3,5-Tri-tert-butylbenzene C18H30 1460-02-2 247.2402 −7.5 14.42 5.31 1435 5 +H 2 10/31 bathroom/toilet (3), kitchen (1), glass (3), automobile (1), carpet (1), bowling ball (1)
- 2,5-Furandicarboxylic acid C6H4O5 3238-40-2 154.9973 −8.1 10.83 15.53 76 2 −H 2 1/31 bathroom/toilet (1)
- - C16H35N - 242.2819 −9.7 9.84 13.84 94273 0 +H 5 3/31 carpet (1), multipurpose (1), bowling ball (1)

Confirmed substances by Reference Standard

Table 3
Substances identified in non-target screening
Chemical group Component name Formula CAS No. Observed m/z Peak Response i-FTT Confidence(96) Fragment Matches Predicted Intensity (%) Confidence level Frequency Identified sample group
surfactant C12E3 C18H38O4 3055-94-5 319.2845 201520 97.09 3 12 3 1/31 automobile (1)
surfactant Dimethyltridecylamine oxide C15H33NO 5960-96-3 244.261 35735 100 5 95 3 1/31 automobile (1)
surfactant Dodecylamine C12H27N 124-22-1 186.2192 67500 100 4 37 3 7/31 bathroom/toilet (3), glass (1), metal (2), automobile (1)
surfactant Myristamine oxide C16H35NO 3332-27-2 258.2773 90125 100 8 2 3 1/31 automobile (1)
surfactant Oleamide C18H35NO 301-02-0 282.2778 65177 100 11 40 3 22/31 bathroom/toilet (5), kitchen (4), glass (4), metal (1), automobile (1), air conditioner (1), carpet (2), multipurpose (2), floor (1), bowling ball (1)
surfactant Myristamide C14H29NO 638-58-4 228.2305 45153 100 10 49 3 1/31 kitchen (1)
emulsifier Dimantine C20H43N 124-28-7 298.3437 29908 100 7 97 3 1/31 glass (1)
emulsifier Heptadecylamine C17H37N 4200-95-7 256.207 1700 100 6 96 3 1/31 glass (1)
emulsifier Myreth-3 C20H42O4 26826-30-2 347.3158 111461 98.59 3 19 3 1/31 floor (1)
emulsifier N,N-Dimethylpalmitylamine C18H39N 112-69-6 270.3138 5452369 100 5 92 3 1/31 glass (1)
fragrance Diethyl caprylamide C12H25NO 996-97-4 200.1978 1412 100 4 4 3 1/31 bathroom/toilet (1)
fragrance (. + −.)-Limonene C10H16 138-86-3 137.1304 5151 100 3 44 3 1/31 bathroom/toilet (1)
PFAS methyl(trifluoromethyl) dioxirane C3H3F3O2 115464-59-0 129.0163 4512 99.51 4 72 3 1/31 bathroom/toilet (1)
PFAS 1,1,1-Trifluoro-4-penten-2-ol C5H7F3O 77342-37-1 141.0526 77918 99.87 4 94 3 1/31 air conditioner (1)
PFAS 2-Hydroxy-2-(trifluor omethyl)butyric acid C5H7F3O3 72114-82-0 173.0425 8311 90.63 12 55 3 1/31 bathroom/toilet (1)
PFAS 4,4,4-Trifluorobutanal C4H5F3O 406-87-1 127.0371 3069 96.4 4 87 3 1/31 bathroom/toilet (1)
antistatic agent Isostearamidopropyl dimethylamine C23H48N2O 67799-04-6 369.3825 30158 100 5 96 3 1/31 air conditioner (1)
antistatic agent Octadecylamine C18H39N 124-30-1 270.314 121167 100 6 95 2 5/31 bathroom/toilet (1), kitchen (1), glass (1), automobile (1), carpet (1)
viscosity controlling Lauramide C12H25NO 1120-16-7 200.198 2965 100 6 9 3 1/31 glass (1)
antistatic agent Lauramidopropyl dimethylamine C17H36N2O 3179-80-4 285.2884 8515 100 12 95 3 2/31 kitchen (1), air conditioner (1)
antistatic agent Palmitamidopropyl dimethylamine C21H44N2O 39669-97-1 341.3511 486113 100 8 98 3 3/31 bathroom/toilet (1), kitchen (1), air conditioner (1)
- Diisopropyl methylphosphonate C7H17O3P 1445-75-6 181.099 2975 99.55 4 54 3 1/31 bathroom/toilet (1)
- Elaidamide C18H35NO 4303-70-2 282.2775 2078 100 12 4 3 1/31 air conditioner (1)
- Halaminol A C14H29NO 389125-56-8 228.2311 1101 100 3 68 3 1/31 bathroom/toilet (1)
- N-{4-[Isopropyl(methyl)ami no]cyclohexyl}-L-valinamide C15H31N3O 1354011-21-4 270.2526 1705 100 4 3 3 2/31 air conditioner (1), carpet (1)
- N-methyldidodecylamine C25H53N 2915-90-4 368.4231 3024 100 4 10 3 2/31 glass (1), automobile (1)
- N-Methyldodecanamide C13H27NO 27563-67-3 214.2145 5151 100 3 12 3 1/31 bathroom/toilet (1)
- N-Octylcyclohexanamine C14H29N 1211502-51-0 212.2354 1321 100 7 81 3 2/31 bathroom/toilet (1), automobile (1)
- Palmitoleylamine C16H33N 40853-88-1 240.2661 1983 100 7 58 3 1/31 automobile (1)
- Petroselinamide C18H35NO 24222-02-4 282.2778 4461 100 21 34 3 1/31 glass (1)
- Spisulosine C18H39NO 196497-48-0 286.3087 1741 100 5 0 3 1/31 automobile (1)
- Xestoaminol C C14H31NO 129825-28-1 230.2464 20519 100 9 37 3 1/31 bathroom/toilet (1)
- 1,1,1-Trifluoro-4,4-dimethoxy-2-methyl-2-butanol C7H13F3O3 73893-35-3 203.0893 14373 95.28 4 33 3 1/31 bathroom/toilet (1)
- 1,6-Diazidohexane C6H14N6 13028-54-1 171.1358 1096 98.99 3 4 3 1/31 kitchen (1)
- 1-(1-Piperidinyl)-1-octadecanone C23H45NO 4629-04-03 352.3548 1889 100 16 35 3 1/31 glass (1)
- 1-[4-(2-Methyl-2-propanyl)cy clohexyl]-4-piperidinol C15H29NO 416868-99-0 240.2303 1367 100 3 100 3 1/31 kitchen (1)
- 1-Isocyano-1-methoxy-2-methylpropane C6H11NO 109434-22-2 114.0892 1773 100 3 94 3 1/31 bathroom/toilet (1)
- 2-(Hydroxyamino)-2-methyl-1-propanol C4H11NO2 4706-13-2 106.0846 1342 99.12 3 100 3 1/31 kitchen (1)
- 2-Isopropyl-2-oxazoline C6H11NO 10431-99-9 114.0892 3071 100 4 95 3 1/31 bathroom/toilet (1)
- 2-Methyl-2-[(2-methyl-2-butanyl)peroxy]-3-nonadecyne C25H48O2 303156-31-2 381.3729 3640 100 23 20 3 2/31 glass (1), air conditioner (1)
- 2,2-Bis(diethylaminomethyl)-1,3-propanediol C13H30N2O2 63863-51-4 247.2393 5820 92.14 5 3 3 4/31 glass (1), automobile (1), air conditioner (1), carpet (1)
- 3-Methyl-1-dodecyn-3-OL C13H24O 24424-78-0 197.1881 1182 100 4 15 3 1/31 bathroom/toilet (1)
- (Z)-N-Isopropyl-9-octadecen amide C21H41NO 10574-01-3 324.3237 2546 100 4 100 3 1/31 kitchen (1)
- (3S)-4,4,4-Trifluoro-1,3-buta nediol C4H7F3O2 135154-88-0 145.0473 19586 98.85 6 56 3 6/31 bathroom/toilet (2), kitchen (1), automobile (1), air conditioner (1), multipurpose (1)
- (9Z)-N,N-Dibutyl-9-octadece namide C26H51NO 5831-80-1 394.4015 1723 100 3 5 3 1/31 metal (1)
- (9Z)-N-Methyl-9-octadecena mide C19H37NO 70858-46-7 296.2927 2144 100 6 60 3 1/31 kitchen (1)
- - C15H29NO - 240.2302 3152 100 13 65 4 1/31 air conditioner (1)
- - C10H16 - 137.1305 1534 100 3 41 4 1/31 bathroom/toilet (1)
- - C13H29N - 200.236 1087 100 8 74 4 1/31 bathroom/toilet (1)
- - C10H24N6 - 229.2138 1985 99.25 5 9 4 1/31 kitchen (1)
- - C23H48N2O - 369.3822 2136 99.14 3 98 4 1/31 bathroom/toilet (1)
Table 4
Estimated daily intake (EDI), hazard quotient (HQ) of three substances identified by reference standards
Chemical name EDI (μg/kg bw/day) HQ (μg/kg bw/day)
bathroom/toilet
tributyl citrate acetate 5.38.E-04 1.79.E-06
glyceryl monostearate 1.71.E-04 N.A*
2-(2-butoxyethoxy)ethyl acetate 2.96.E-04 9.40E-08
kitchen
tributyl citrate acetate 3.76.E-04 1.25.E-06
glyceryl monostearate 3.31.E-04 N.A
2-(2-butoxyethoxy)ethyl acetate 1.08.E-03 3.44E-07
glass
tributyl citrate acetate 6.83.E-04 2.28.E-06
glyceryl monostearate 5.94.E-04 N.A
2-(2-butoxyethoxy)ethyl acetate 5.50.E-04 1.75E-07
multipurpose
tributyl citrate acetate 3.62.E-04 1.21.E-06
glyceryl monostearate N.A N.A
2-(2-butoxyethoxy)ethyl acetate N.A N.A

N.A: Not available

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