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Study Findings

Greener School Cleaning Supplies: Study Findings

November 3, 2009

Classroom Cleaners Release 457 Air Pollutants

All across California, children spend many hours of the day in schools cleaned by products that can pollute classroom air. Cleaning supplies release 32 tons of contaminants into the air each day in California alone (CARB 2003; Nazaroff 2004).

EWG-commissioned tests of commonly used school cleaners reveal the wide range of chemicals children can breathe in each day at school. More than 20 products were selected based on a survey of the cleaning supplies used by several major California school districts, and tested individually by a leading laboratory that specializes in studying air pollution released by cleaning products. In a key part of this investigation, this state-of-the-art air quality laboratory cleaned a model classroom using multiple products at the same time, a first-of-its-kind test to measure the real-world pollution that occurs when typical assortments of cleaning supplies are used together.

The results are alarming. For example, some of the cleaning supplies used at home as well as at school release the highest number of contaminants measured. Some cleaners that appear "green" are anything but, misleading schools and consumers with marketing claims. Certified green cleaners, those meeting strict standards from independent groups, emit fewer contaminants on average and are safer choices for schools.

Key findings:

  • 457 distinct air contaminants were released by the 21 cleaning products tested. Comet Disinfectant Powder Cleanser emitted 146 contaminants, more than any other product tested. Glance NA, a certified green janitorial glass and general purpose cleaner, emitted just one air contaminant, the fewest detected.
  • 24 of the chemicals found in these cleaners have well-established links to asthma, cancer, and other serious health concerns, including 12 of the State of California's Proposition 65 chemicals linked to cancer, birth defects, or reproductive toxicity.
  • Certified green general purpose cleaners tested released an average of eight air contaminants, while those not certified released nearly five times as many, an average of 38 different contaminants each. Compared to conventional general purpose cleaners, the certified green products contained just one-quarter of the chemicals with documented ties to specific health concerns such as asthma and cancer. A comparison of all products tested shows certified green cleaning supplies released half as many air contaminants as conventional products, and contained one-third the chemicals with known health concerns.
  • Cleaning a classroom with certified green products releases less than one-sixth of the total air pollution released by cleaning a classroom with conventional cleaners.

Cleaning supplies, dirty air:

EWG's testing of more than 20 cleaning products used in California schools detected a total of 457 chemicals released into the air. Limited information provided by manufacturers revealed the presence of 42 other chemical ingredients that were not measured in air samples, typically because they are not volatile. Manufacturers are legally required to disclose only a specific handful of cleaner ingredients due to acknowledged health concerns and occupational safety standards associated with each of them.

The results show dramatic variation in the numbers of contaminants released by each product tested: Comet Disinfectant Powder Cleanser emitted 146 distinct chemicals into the air, while a certified green glass and general-purpose cleaner, Glance Non-Ammoniated (NA) Glass and Multi-Purpose Cleaner, emitted just one air contaminant.

Some of the worst offenders, such as Comet Disinfectant Powder Cleanser, are household cleaning supplies commonly used in homes across America. When used at full-strength, the well-known cleaner Simple Green, which claims to be "non-toxic," gave off 93 different air contaminants; a Febreze Air Effects air freshener released 89.

Generally, certified green cleaning products released significantly fewer air contaminants than their conventional counterparts. On average, green general purpose cleaners released one-fifth as many contaminants as conventional general purpose cleaners. Broadening the comparison to include all cleaning supplies tested, certified green products emitted half as many contaminants as conventional cleaning supplies.

Certified green cleaning supplies release fewer air contaminants

Source: Air pollution test results for school cleaning supplies.

Note: Certified Green Products included in EWG tests are those certified by Green Seal or EcoLogo (Green Seal 2008; EcoLogo 2007, 2008).

Especially polluting cleaning product types included air fresheners, graffiti removers, and floor finishes.

Cleaning products can affect our health:

Twenty four air contaminants detected by EWG tests may cause asthma, cancer, and other serious health concerns affecting children and adults, according to U.S. and international health agencies. Seven more toxic cleaning chemicals that can linger on surfaces and contaminate dust are disclosed as ingredients by product manufacturers.

Ten of the products tested contained one or more of the chemicals known to the State of California to cause cancer or reproductive or developmental toxicity: Alpha HP Multi-Surface Cleaner, Citrus-Scrub 90, Comet Disinfectant Powder Cleanser, Febreze Air Effects, Goof Off Cleaner (CA VOC Compliant), Pine-Sol Brand Cleaner (Original), Pioneer Super Cleaner, Shineline Seal Floor Sealer/Finish, Simple Green Concentrated Cleaner/Degreaser/Deodorizer, and Waxie Green Floor Finish. Twelve of these toxic chemicals, known widely as Proposition 65 chemicals, are found in the cleaning supplies we tested, including:

  • Benzene, a solvent and contaminant linked to cancer and male reproductive system toxicity (Comet Disinfectant Powder Cleanser)
  • Chloroform, a gas that causes cancer and developmental toxicity (Comet Disinfectant Powder Cleanser)
  • Dibutyl phthalate, an emulsifier known to damage developing male and female reproductive systems (Shineline Seal Floor Sealer/Finish).
  • Formaldehyde, a cancer-causing gas also emitted by some building materials and furniture (Simple Green Concentrated Cleaner/Degreaser/Deodorizer, Pine-Sol Original Cleaner, Comet Disinfectant Powder Cleanser, Super Cleaner Concentrate)

Comet Disinfectant Powder Cleanser alone emitted seven Proposition 65 chemicals.

Products that expose users to Proposition 65 chemicals above legally prescribed levels must be clearly labeled as such under the law, to allow individuals and institutions such as schools to choose safer products. Recently, the manufacturer of the graffiti remover Goof Off was successfully sued by a public interest law firm because its Proposition 65 warning label was insufficient (As You Sow v. The Valspar Corporation, 2008). The Goof Off purchased for this study featured an appropriate Proposition 65 warning on the product.

Certified green products contained fewer known toxic ingredients, according to EWG's laboratory tests and company documents. On average, green general purpose cleaners contained one-fourth as many chemicals with documented health concerns as similar conventional products. Among all cleaning supplies tested, certified green products contained one-third the chemicals with documented health concerns.

Certified green cleaning supplies contain fewer chemicals with documented health concerns

Source: Air pollution results for school cleaning supplies.

Note: Certified Green Products included in EWG tests are those certified by Green Seal or EcoLogo (Green Seal 2008; EcoLogo 2007, 2008). Chemicals highlighted are those listed by leading authorities on asthma, cancer, reproductive toxicity, hormone disruption, and neurotoxicity, and are listed and documented in the Table below.

Leading green certifications include Green Seal (GS-37, Environmental Standard for Industrial and Institutional Cleaners) and EcoLogo (CCD-146, standard for Hardsurface Cleaners, and CCD-147 standard for Hard Floor Care Products). Green Seal GS-37 and EcoLogo CCD-146 establish environmental and health requirements for general purpose, restroom, glass, and carpet cleaners, intended for routine cleaning of schools, offices, and institutions. EcoLogo CCD-147 establish similar requirements for floor polish, strippers and other floor maintenance products. The cleaning product criteria state that certified products will not contain ingredients that are carcinogens, mutagens, or reproductive toxins; heavy metals such as lead and cadmium; common cleaning chemicals of concern including 2-butoxyethanol, alkylphenol ethoxylates, and phthalates; ozone-depleting chemicals; and optical brighteners. Green Seal's standard was recently revised to include a prohibition on chemicals that are known to cause asthma through a process called respiratory sensitization. (Green Seal has also established a GS-40 floor care products standard, with less stringent criteria than those outlined above.) The EcoLogo standard also prohibits a number of ingredients based on their suspected hormone-disrupting properties.

Green Seal and EcoLogo standards, which are revised periodically, also establish specific limits on ingredients for acute toxicity; skin absorption; inhalation toxicity; toxicity to aquatic life; bioaccumulating compounds; nutrient pollution; and fragrances. Additional criteria in these standards also limit a product's pH, combustability, volatile organic compound (VOC) content, and biodegradability. The criteria define requirements for concentrates; dispensing systems; packaging; recyclability; labeling; and training. These particular standards do not include cleaners for household use, and do not apply to air fresheners, graffiti removers, or to disinfecting or "antimicrobial" cleaners.

Despite these standards, some certified products did emit asthmagens, carcinogens, and reproductive toxins. Some of these offending products were certified under earlier versions of a green standard and have not yet been reformulated to reflect the latest standard. Others emit toxic chemicals still allowable under their particular certification standard, and some release chemicals specifically prohibited as ingredients according to their own certification. Just two of six green products were completely free of all the asthmagens, carcinogens, and reproductive toxins addressed by current standards, according to EWG tests. Just 1 of 16 conventional products tested was free of all of these chemicals.

Dozens of chemicals in cleaning supplies are tied to human health risks:

Health Concern Chemicals detected by EWG tests or disclosed as ingredients Products containing one or more of these chemicals (number of relevant chemicals)
Asthmagens: chemicals that can trigger the development of asthma in previously asthma-free individuals - 6 chemicals from 10 school cleaners

Alkyl dimethyl benzyl ammonium chloride (ADBAC)

Didecyl dimethyl benzyl ammonium chloride

Ethanolamine

Formaldehyde

Methyl methacrylate

Styrene

3M Brand Glass Cleaner (Product No. 1, Twist 'n Fill System) (1)

Comet Disinfectant Powder Cleanser (1)

NABC Non-Acid Disinfectant Bathroom Cleaner (1)

Pine-Sol Brand Cleaner (Original) (1)

Pioneer Super Cleaner (2)

Ripsaw (1)

Shineline Seal Floor Sealer/Finish (1)

Simple Green Concentrated Cleaner/Degreaser/Deodorizer (1)

Virex II 256 (1)

Waxie Green Floor Finish (1)

Carcinogens - 11 chemicals from 11 school cleaners

Acetaldehyde

Benzene

2-Butoxyethanol

1-Chloro-2,3-epoxypropane

Chloroform

Ethylbenzene

Formaldehyde

N-Ethyl-N-nitroso-ethanamine

Quartz*

Styrene

Trichloroethylene

Citrus-Scrub 90 (1)

Comet Disinfectant Powder Cleanser (7)

Febreze Air Effects (1)

Glance HC Glass and Multi-Surface Cleaner (1)

Goof Off Cleaner (CA VOC Compliant) (1)

Pine-Sol Brand Cleaner (Original) (1)

Pioneer Super Cleaner (2)

Shineline Seal Floor Sealer/Finish (1)

Simple Green Concentrated Cleaner/Degreaser/Deodorizer (3)

Waxie 21 Glass Cleaner (1)

Waxie Green Floor Finish (1)

Reproductive Toxins - 4 chemicals from 4 school cleaners.

Benzene

Dibutyl phthalate*

Ethoxyethanol

Toluene

Alpha HP Multi-Surface Cleaner (1)

Comet Disinfectant Powder Cleanser (2)

Goof Off Cleaner (CA VOC Compliant) (1)

Shineline Seal Floor Sealer/Finish (2)

Hormone Disruptors - 8 chemicals from 9 school cleaners

Benzophenone

1-Chloro-2,3-epoxypropane

Dibutyl phthalate*

Ethylene glycol

N,N-Dimethylformamide

Nonylphenol ethoxylate*

Phenol

Styrene

3M Brand Glass Cleaner (Product No. 1, Twist 'n Fill System) (1

Clorox Regular Bleach (1)

Comet Disinfectant Powder Cleanser (2)

Glance HC Glass and Multi-Surface Cleaner (1)

Goof Off Cleaner (CA VOC Compliant) (2)

Shineline Seal Floor Sealer/Finish (3)

Simple Green Concentrated Cleaner/Degreaser/Deodorizer (2)

Twister (1)

Waxie 21 Glass Cleaner (1)

Neurotoxins - 17 chemicals from 15 school cleaners

Acetone*

Benzene

Benzonitrile

Benzyl alcohol

Chloroform

Cyclohexanone

Dibutyl phthalate*

N,N-Dimethylformamide

Ethyl acetate

Isopropyl alcohol

Methyl ethyl ketone

Methyl methacrylate

Phenol

Styrene

Toluene

Trichloroethylene

Xylene

3M Brand Bathroom Cleaner (Product No. 44, Twist 'n Fill System) (1)

Alpha HP Multi-Surface Cleaner (1)

Citrus-Scrub 90 (1)

Clorox Regular Bleach (1)

Comet Disinfectant Powder Cleanser (5)

Febreze Air Effects (1)

Goof Off Cleaner (CA VOC Compliant) (4)

NABC Non-Acid Disinfectant Bathroom Cleaner (1)

Pine-Sol Brand Cleaner (Original) (1)

Ripsaw (1)

Shineline Seal Floor Sealer/Finish (3)

Simple Green Concentrated Cleaner/Degreaser/Deodorizer (1)

Virex II 256 (1)

Waxie 21 Glass Cleaner (1)

Waxie Green Floor Finish (1)

*Chemicals not detected in air contaminant tests, but disclosed as ingredients by manufacturers

Asthmagens identified by the Association of Occupational and Environmental Clinics (AOEC 2009).

Carcinogens identified by International Agency for Research on Cancer (IARC) as known, probable, reasonably anticipated, or possible human carcinogens (IARC; Groups 1, 2A, and 2B), the National Toxicology Program (Groups 1 and 2), the EPA Integrated Risk Information System (weight-of-evidence classifications A, B1, B2, C, carcinogenic, likely to be carcinogenic, and suggestive evidence of carcinogenicity or carcinogen potential), or the Occupational Safety and Health Administration (as carcinogens under 29 CFR 1910.1003(a)(1))

Reproductive toxins identified by the State of California under the Safe Drinking Water and Toxic Enforcement Act of 1986 (California Code of Regulations, Title 22, Division 2, Subdivision 1, Chapter 3, Sections 1200, et. seq., also known as Proposition 65).

Hormone disruptors identified by the European Union in Appendix 9 of Towards the Establishment of a Priority List of Substances for Further Evaluation of Their Role in Endocrine Disruption (European Commission DG ENV 2000, 2007)

Neurotoxins identified in literature review by Grandjean and Landrigan (2006).

While it is troubling to note the presence of chemicals linked to health risks in the majority of the cleaners tested, a higher level of concern may be appropriate for those chemicals disclosed by manufacturers. Cleaning product makers typically disclose only those ingredients both tied to specific occupational health risks and making up more than one percent of the product, or 0.1 percent if the ingredient is a carcinogen. Thus, chemical ingredients disclosed by companies are typically primary ingredients present at significant concentrations, rather than trace contaminants present at much lower levels.

Some key chemicals of concern in cleaning supplies:

Many conventional cleaning products rely on a relatively small set of chemical ingredients linked to serious health concerns. Highlighted below are two chemicals commonly detected in the air following cleaning, as well as a class of chemicals frequently found in cleaners.

Formaldehyde

Detected in:

  • Comet Disinfectant Powder Cleanser
  • Pine-Sol Brand Cleaner
  • Pioneer Super Cleaner
  • Simple Green Concentrated Cleaner/Degreaser/Deodorizer

Recognized as a "known" human carcinogen by the International Agency for Research on Cancer (IARC 2004), formaldehyde is a common indoor air contaminant released by cleaning products, as well as by other school and consumer goods, including plywood or particle-board furniture, building materials, and nail polish. The California Air Resources Board's Scientific Review Panel has concluded that there is no safe level of exposure to this cancer-causing chemical (CARB 1992).

Formaldehyde can form indirectly when terpenes from pine- and citrus-based cleaners react with trace levels of ozone in the air. For this reason, the California Air Resources Board recommends avoiding use of citrus and pine oil cleaners, especially on smoggy days when levels of ozone are high (CARB 2008).

Formaldehyde is "generally accepted" as an asthmagen by the Association of Occupational and Environmental Clinics (AOEC 2009). Cleaning products certified by Green Seal must not contain ingredients that AOEC defines specifically as sensitizer-induced asthmagens (chemicals that induce asthma by sensitizing, rather than irritating, the respiratory system), a designation that the organization has not assigned to formaldehyde. As a result, this chemical is not prohibited as an asthmagen according to the current Green Seal certification, although it is prohibited as a carcinogen. Formaldehyde is highly corrosive, capable of damaging eyes, skin, and lungs.

2-Butoxyethanol (also known as ethylene glycol monobutyl ether or EGBE)

Detected in:

  • Glance HC Glass & Multi-Surface Cleaner
  • Goof Off Cleaner (CA VOC Compliant)
  • Pioneer Super Cleaner
  • Shineline Seal Floor Sealer/Finish
  • Simple Green Concentrated Cleaner/Degreaser/Deodorizer
  • Waxie 21 Glass Cleaner
  • Waxie Green Floor Finish

Many chemicals within the glycol ether family are linked to impaired fertility and reproductive and developmental toxicity in animal studies (EPA 2000; NTP 2000) and four are on California's Proposition 65 list of male developmental toxins. Occupational studies indicate that men exposed to glycol ethers on the job are more likely to have reduced sperm counts, while pregnant women exposed on the job are more likely to give birth to children with birth defects (Cordier 1997; CDHS 2007). These solvents can reach toxic levels in the body by being readily absorbed through the skin or via inhalation; glycol ether solvents can damage the lungs and may be linked to asthma.

2-Butoxyethanol is a glycol ether that is commonly found in cleaning supplies. Exposure to 2-butoxyethanol can damage red blood cells, which could lead to anemia (NTP 2000). It is a "possible" human carcinogen (EPA 1999), and may be toxic to the reproductive system as well (NTP 2000). Routine home cleaning using 2-butoxyethanol cleaners can result in air contamination that exceeds established health-based limits for the workplace (Nazaroff 2006). This chemical is specifically prohibited in the certified green cleaners tested.

Quaternary ammonium compounds (quats, including alkyl dimethyl benzyl ammonium chloride and didecyl dimethyl benzyl ammonium chloride)

Disclosed as ingredients of:

  • NABC Non-Acid Disinfectant Bathroom Cleaner
  • Virex II 256

Many other chemicals of concern commonly found in cleaning supplies cannot be detected by air pollution tests because they do not vaporize into the air. Instead, these chemicals form residues that remain on desks, floors, and other cleaned surfaces. These chemicals can adhere to children's skin, including their hands, where exposure can occur through ingestion or absorption through the skin. These chemicals may also build up in dust, leading to exposures through inhalation, ingestion, and skin absorption.

For example, residues of non-volatile quaternary ammonium compounds (quats) in cleaning products can cause or exacerbate asthma (AOEC 2009). Surveys of house cleaners, health care workers, and others link exposure to quat-based cleaners to asthma symptoms and the development of work-related asthma (Preller 1996; Purohit 2000; Rosenman 2003; Delclos 2007). A quat-based disinfectant called Virex, similar to one used in multiple school districts in California and tested in this study (Virex II 256), was recently identified by noted scientist Dr. Patricia Hunt as the cause of a severe decline in the fertility of a laboratory mouse population -- preliminary evidence that quats may be reproductive toxins (Hunt 2008). Recent tests using human blood cells also indicate that quats can damage DNA at levels far below those found in cleaning products (Ferk 2007). Overuse of quats may lead to development of antimicrobial resistance; bacterial colonies specifically resistant to these antimicrobial agents have already been identified in food production facilities (Mullapudi 2008).

A note on disinfectants and flu:

The flu virus and other infectious diseases can spread easily in schools, and the emergence of the H1N1 "swine flu" this year has heightened concerns because it appears to be especially prevalent among children and young adults.

Most health authorities recommend frequent hand washing and careful cleaning as the best ways to reduce the risk of flu. In particular, the Centers for Disease Control and Prevention (CDC) and the California Department of Public Health (CDPH) recommend regularly cleaning and sanitizing all areas and items that are likely to be frequently touched and immediate cleaning of visibly soiled areas (CDC 2009; CDPH 2009). Both agencies endorse recommendations by the American Academy of Pediatrics (AAP 2009) calling for daily cleaning and sanitizing of surfaces such as desks, countertops, floors, and doorknobs.

Neither government agency recommends use of disinfectants beyond measures already in place to keep schools clean. Instead, they urge frequent hand washing and isolating sick students and staff as the best means to control the H1N1 virus (CDC 2009; CDPH 2009).

General purpose cleaners can remove significant numbers of infectious germs, and many schools also use disinfectants or less potent sanitizers that contain EPA-registered pesticides to further control the spread of communicable diseases. While judicious use of disinfectants and sanitizers may play a role in controlling the virus in schools, overusing them does not provide any additional protection and can expose school children and staff to toxic chemicals. In addition, the American Medical Association warns that overuse of antimicrobial products could cause germs to develop resistance to useful antibiotics and make them ineffective (Tan 2002). When disinfectants or sanitizers are used, they should be carefully selected to minimize children's exposures to toxic ingredients while achieving the desired level of germ control. Depending on the product used and the setting, this may involve a) cleaning surfaces first to remove soil that can shelter germs from disinfection or sanitization, b) careful dilution of the product, preferably using automatic dilution equipment that controls its concentration, c) applying an appropriate amount to surfaces using tools that minimize waste, such as microfiber cloths, d) allowing the product to remain in place long enough (dwell time) to kill germs, and e) removing or rinsing away residues, according to the product label. It is crucial to train custodians how to use these products correctly to protect both school children and custodians themselves.

Under U.S. law, disinfectants cannot make "green" claims. Certified green cleaning products are intended to replace conventional cleaning agents, not disinfectants.

Real-world classroom cleaning -- clear benefits to going green:

In a first-of-its-kind analysis, a leading air quality laboratory compared contaminants released when cleaning classrooms with typical assortments of conventional and green cleaning products. These tests clearly demonstrated that green products emit less than one-sixth of the pollution of conventional products. Previous studies typically examined cleaning compounds individually and failed to capture the real-world air contamination created by simultaneous use of multiple cleaning products.

Technicians, following carefully prescribed cleaning regimens based on findings from California's Air Resources Board (Nazaroff 2006), cleaned a model classroom with regular or green cleaning supplies. In the conventional classroom they mopped floors with Twister, wiped windows with Waxie 21 Glass Cleaner, and cleaned desks, bookshelves, and a whiteboard with Simple Green, simulating conventional cleaning with products widely used in California schools. In the green classroom, they mopped floors with Marauder Environmental Cleaner, wiped windows with Glance NA, and cleaned desks and other surfaces with Alpha HP (cleaner strength) -- all products used in California school districts that have made the switch to green cleaners. The air quality laboratory pumped purified air through the model classroom chamber during and after cleaning at a rate of a room's worth of air per hour, and collected the outgoing air for analysis.

A total of 75 air contaminants were detected in these model classroom tests. The room-sized test chamber allowed scientists to both identify contaminants and measure their concentrations reliably. These classroom cleaning tests thus allow comparison of overall air pollution measured as total volatile organic compounds (VOCs), as well as comparison of the number of different air contaminants released.

The results are clear -- levels of VOCs are less than one-sixth as high in the green classroom. The number of different individual chemical contaminants detected in the green classroom is one-third to one-fifth as high at every time point measured as well. Green cleaning products produced markedly safer, cleaner indoor air in the classroom -- and are certified to perform at least as well as conventional cleaners.

Cleaning a classroom with green products releases one-sixth the overall air pollution

Source: All measurements for conventional and green classroom cleaning scenarios may be found in the Data Appendix.

Conventional cleaning supplies used: Twister (floor), Waxie 21 Glass Cleaner (windows), Simple Green (desks and other surfaces).

GCertified green cleaning supplies used: Marauder Environmental Cleaner (floor), Glance Non-Ammoniated Glass & Multi-Purpose Cleaner (windows), Alpha HP Multi-Surface Cleaner (desks and other surfaces).

A key chemical of concern measured in the conventional cleaning scenario is 2-butoxyethanol, classified as a "possible" human carcinogen according to EPA (1999), with levels peaking at over 2,000 micrograms per cubic meter of air. This peak measurement is below government guidelines suggesting that levels of 2-butoxyethanol must be lower than 14,000 micrograms per cubic meter of air over a one-hour period to protect those exposed from eye and lung irritation (OEHHA 2008). This guideline was not designed to protect adults or children from increased risk of cancer; long-term exposures to 2-butoxyethanol may be a serious health concern at the lower levels.

Formaldehyde, a known human carcinogen, was detected at trace levels of around three micrograms per cubic meter of air, in both the conventional and green cleaning scenarios.

In addition, 15 air contaminants detected in the conventional cleaning scenario were not detected by any of the tests of individual products used to clean the classroom; in the green cleaning scenario, 10 new air contaminants were detected due to use of a mixture of green products. Trace levels of these chemicals may arise due to the interaction of the cleaning products with each other, or with the cleaning materials used to apply the products. Differences in detection may also stem from differences in sensitivity between the small-scale individual product tests and the larger-scale classroom cleaning tests.