The Home Chemical Almanac · Chapter 7
Disinfectants and antibacterials
Correct as of November 2026.
If the label says "disinfectant", "antibacterial" or "hospital grade"
Disinfecting kills germs left on a surface after cleaning. Dirt protects germs, so surfaces need cleaning first, and most homes need cleaning far more often than disinfecting.
In Australia, a product that claims to kill germs on surfaces is a disinfectant under therapeutic goods law, overseen by the Therapeutic Goods Administration (TGA). A few things the label words don't tell you:
- "Hospital grade" is legally about where a product is meant to be used. It has to pass tougher tests, but the TGA says "many products labelled as household disinfectants contain the same active ingredients as products labelled as hospital grade disinfectants." A household disinfectant must not be labelled "hospital grade".
- "Kills 99.9% of germs" isn't a TGA test result. The TGA's tests are pass/fail. A claim to kill viruses, fungi, spores or tuberculosis means the product must be listed with the TGA before sale. A general "kills germs" claim doesn't need listing, but the product must still pass the TGA's tests.
- A disinfectant label must name its active ingredients and how much of each, and (except for sprays and wipes) say "Do not mix with detergents or other chemicals".
- General cleaners, and food-surface sanitisers that make no disinfectant claims, aren't regulated by the TGA. Hand sanitisers are TGA-regulated only if they claim more than killing bacteria (for example, killing viruses), unless they follow one of the TGA's set formulas, such as the WHO recipes; otherwise they're treated as cosmetics or consumer goods.
Bleach, hydrogen peroxide and peracetic acid are in Chapter 4, citric and lactic acid in Chapter 10, and benzalkonium chloride in Chapter 6.
Cheat sheet
| Chemical | Badges | Also on labels as | Worst fact | Take care if |
|---|---|---|---|---|
| DDAC | — | didecyldimethylammonium chloride, quat | Hospital workers exposed to quats reported 7.5 times the odds of diagnosed asthma | asthma, eyes |
| Cetrimonium chloride | — | CTAC, quat | 5% solution caused corneal damage in rabbits | eyes |
| Ethanol | 💧 | alcohol, ethyl alcohol | 70,669 US child hand-sanitiser exposures in 4 years | children, flames |
| Isopropyl alcohol | — | IPA, isopropanol | About twice as toxic as ethanol if swallowed | children, flames |
| Chloroxylenol | ⚠ | PCMX | A PCMX antiseptic: 10% of Hong Kong self-poisoning admissions | eyes, children |
| Triclosan | ☠ 💧 | triclosan | Banned from US antibacterial soaps in 2017 | — |
| 2-Phenylphenol | ⚠ | o-phenylphenol, OPP | Its sodium salt is possibly carcinogenic to humans | skin |
| Chlorocresol | ⚠ 💧 | PCMC, p-chloro-m-cresol | Pure chemical corrosive to eyes and skin | eyes, skin |
| Chlorophene | ⚠ 🛢 | benzylchlorophenol | Kidney tumours in mice; banned in EU cosmetics | bleach, eyes |
| Thymol | — | thyme oil extract | Corrosive, despite the "botanical" label | eyes, skin |
| Paradichlorobenzene | ☠ 🛢 💧 | PDCB, 1,4-dichlorobenzene | Linked to lower lung function; banned in EU air fresheners | children, indoors |
☠ Poison schedule (Australia) · ⚠ Officially classed skin allergen · 🛢 Made from a hazardous chemical · 💧 Contaminant risk
The chemicals
Part 1: Quats
Quaternary ammonium compounds ("quats") are the most common actives in disinfectant sprays and wipes. They work by breaking open germs' outer coats.
Part 2: Alcohols
Alcohols kill bacteria, fungi and enveloped viruses fast, but not spores. They work best at 60 to 90% in water: pure alcohol works less well.
Part 3: Phenols
Part 4: Toilet blocks and mothballs
Safer alternatives
The US CDC says plain soap and water is the best everyday choice for hands, and the US FDA says antibacterial soaps haven't been shown to prevent illness better. In 2017 the FDA removed triclosan and 18 other actives from consumer antibacterial soaps because makers hadn't shown they were safe for long-term daily use or better than plain soap.
Look for these:
- Plain soap and water for hands
- Detergent and water to clean surfaces first, then disinfect only when you need to
- Hand sanitiser at 60 to 90% alcohol, when there's no soap and water
- Products that name their active ingredient, so you know what you're using
Sources
Regulators and official lists
- Australian Government. Therapeutic Goods Regulations 1990 (compilation 131, 2026); Therapeutic Goods Order No. 104 (compilation 3, 2025).
- TGA. Regulation of cleaners and disinfectants (2020); Understanding rules for exempt disinfectants (2024); Disinfectant claim guide; Instructions for disinfectant testing v4.0 (2025); Hand sanitisers: information for consumers; Meeting requirements for hand sanitisers (2024).
- Australian Government. Poisons Standard October 2026 (SUSMP), F2026L01327: didecyldimethylammonium salts; quaternary ammonium compounds; triclosan; o-phenylphenol; chlorocresol; p-dichlorobenzene; thymol; methanol; Appendix B.
- Safe Work Australia. Hazardous Chemical Information System (HCIS): classifications for each chemical, and for benzene and benzyl chloride.
- NICNAS. IMAP: cationic surfactants (2015). Priority Existing Chemical Assessment Report No. 30: triclosan (2009).
- NSW Health. Hand sanitiser safety (2020).
- European Union. Regulation (EU) 474/2014 (1,4-dichlorobenzene); Implementing Decision (EU) 2016/110 (triclosan); Regulation (EU) 358/2014 (triclosan in cosmetics); Regulation (EU) 2019/831 (chlorophene); Regulation (EU) 2014/866 (cetrimonium chloride).
- European Commission SCCS. Opinions on alkyl trimethylammonium chlorides (2009) and triclosan (2010).
- US FDA. Final rule on consumer antiseptic washes, 81 FR 61106 (2016); Skip the antibacterial soap; Safely using hand sanitizer; Hand sanitizer sampling results.
- US CDC. Guideline for disinfection and sterilization (2008); Hand sanitizer guidelines (2024).
- US EPA. Reregistration documents: chloroxylenol (1994), 2-phenylphenol (2006), p-chloro-m-cresol (1996), o-benzyl-p-chlorophenol (1995), thymol (1993); 40 CFR 152.25.
- IARC. Monographs vol. 73 (1999): ortho-phenylphenol; dichlorobenzenes.
- US National Toxicology Program. Technical Report on o-benzyl-p-chlorophenol (1994).
- WHO. Guide to local production of WHO-recommended handrub formulations (2010).
- HSDB (US National Library of Medicine), via PubChem: manufacturing, toxicity and impurity data.
Studies
- Gonzalez M et al. Asthma among workers in healthcare settings: role of disinfection with quaternary ammonium compounds. Clin Exp Allergy 2014;44:393-406.
- Zheng G et al. Quaternary ammonium compounds in human blood during the COVID-19 pandemic. Environ Sci Technol 2021;55:14689-14698.
- Zheng G et al. Elevated levels of QACs in indoor dust during the COVID-19 pandemic. Environ Sci Technol Lett 2020;7:760-765.
- Arnold WA et al. Quaternary ammonium compounds: a chemical class of emerging concern. Environ Sci Technol 2023;57:7645-7665.
- Boyce JM. Quaternary ammonium disinfectants and antiseptics: tolerance, resistance and potential impact on antibiotic resistance. Antimicrob Resist Infect Control 2023.
- Santos C et al. Pediatric exposures to alcohol-based hand sanitizers, 2011–2014. MMWR 2017;66:223.
- Yip L et al. Methanol poisoning from alcohol-based hand sanitizer, Arizona and New Mexico. MMWR 2020;69:1070.
- Norvill A, Elliott RA, Wong A. Antiseptic exposures in children during COVID-19, Victoria. Clin Toxicol 2022;60:745.
- Chan TY et al. Self-poisoning with Dettol. Q J Med 1993;86:735-738.
- DeBono R, Laitung G. Phenolic household disinfectants: further precautions required. Burns 1997.
- Calafat AM et al. Urinary concentrations of triclosan in the US population. Environ Health Perspect 2008.
- Toms LM et al. Triclosan in Australian breast milk. Chemosphere 2011.
- Fiss EM et al. Formation of chloroform from triclosan-containing products. Environ Sci Technol 2007.
- Latch DE et al. Photochemical fate of triclosan. Environ Toxicol Chem 2005.
- Mehrtens SH et al. Contact urticaria with anaphylaxis caused by chlorocresol, chloroxylenol and thiourea. Contact Dermatitis 2019.
- Elliott L et al. Volatile organic compounds and pulmonary function in NHANES III. Environ Health Perspect 2006;114:1210.
- Ye X et al. Urinary 2,5-dichlorophenol in the US population, 2003–2010. Environ Health Perspect 2014;122:351.
- McDonnell G, Russell AD. Antiseptics and disinfectants: activity, action and resistance. Clin Microbiol Rev 1999.