Method hand soap is generally safe for everyday use, but calling it “non-toxic” depends on what you mean by the term. Most Method hand soap formulations earn a “low hazard” rating from the Environmental Working Group, and the brand has held Cradle to Cradle Bronze certification. However, some ingredients in Method soaps, particularly certain preservatives, are known skin sensitizers that can cause reactions in some people. The full picture is more nuanced than a simple yes or no.
What’s Actually in Method Hand Soap
Method’s formulations vary by scent and type (gel vs. foaming), but the core cleaning agents are consistent across the line. The foaming hand soap uses sodium lauryl sulfate (SLS) and cocamidopropyl betaine as its main surfactants. Both are plant-derived but synthetically processed, and both are extremely common in personal care products.
SLS is an effective cleanser, but the EWG classifies it as a moderate hazard because it’s a known skin irritant. For most people washing their hands a few times a day, this isn’t a problem. But if you have eczema, sensitive skin, or wash your hands very frequently, SLS can strip natural oils and leave skin dry, red, or cracked. Cocamidopropyl betaine is milder and often added specifically to reduce the harshness of SLS.
The Preservative Worth Knowing About
The ingredient that raises the most flags in Method hand soap is methylisothiazolinone (MI), sometimes paired with methylchloroisothiazolinone (MCI). These preservatives prevent bacterial growth in the soap, and they appear in many Method formulations, including popular scents like Wild Meadow, Rose Water, Basil, and Fresh Pineapple.
MI and MCI are effective preservatives, but they’re also well-documented skin sensitizers. The European Scientific Committee on Consumer Safety has flagged MI as a concern in leave-on products, and many dermatologists consider it a common cause of contact allergic dermatitis. In a rinse-off product like hand soap, the exposure time is short, which reduces risk. Still, if you’ve ever developed an itchy rash or redness from a soap or lotion, these preservatives are a possible culprit. People with known sensitivity to isothiazolinones should avoid Method formulations that contain them.
Method’s Free + Clear line skips added fragrance and essential oils but still contains both MCI and MI in its foaming formula. So “fragrance free” doesn’t automatically mean “free of potential irritants.”
How Safety Ratings Stack Up
The Environmental Working Group rates a wide range of Method hand soaps as “low hazard” in its Skin Deep database. This covers both gel and foaming versions across many scents, from Orange Slice to Wild Dewberry to Kitchen Basil. A low hazard rating means the ingredients, at the concentrations used, pose minimal health concerns for the general population based on available data.
Method has also received Cradle to Cradle Bronze certification under Version 3.1 of the Cradle to Cradle standard. This certification evaluates material health, recyclability, and manufacturing practices. Bronze is the entry-level tier (the scale runs Bronze, Silver, Gold, Platinum), so it represents a baseline of ingredient transparency and safety rather than the highest standard possible.
What “Non-Toxic” Actually Means
There’s no regulated definition of “non-toxic” for consumer soap products, which is part of why the question is hard to answer cleanly. Under FTC Green Guides, a non-toxic claim implies a product is non-toxic to both humans and the environment. A company making that claim needs competent scientific evidence to back it up for both categories, or it needs to clearly qualify the statement. The FTC specifically warns that a product safe for humans but harmful to the environment would be deceptive if marketed as non-toxic.
Method markets itself as using “plant-based” and “naturally derived” ingredients rather than explicitly claiming “non-toxic.” These are softer terms. The soap’s surfactants are derived from plant sources like coconut oil, but they undergo significant chemical processing. “Naturally derived” is accurate but can give the impression of something gentler than the final product actually is.
Environmental Impact of the Ingredients
One dimension of toxicity that matters beyond your skin is what happens after the soap goes down the drain. Research published in PLOS One compared synthetic detergent compounds like SLS against traditional soap-based surfactants (fatty acid salts) for aquatic toxicity and biodegradability. The findings put SLS in a less favorable light.
In algae toxicity tests, SLS showed harmful effects at 24 mg/l, while natural soap compounds didn’t cause harm until concentrations reached 115 to 148 mg/l, meaning aquatic organisms can tolerate roughly five to six times more natural soap before experiencing damage. The pattern held for crustaceans: SLS became toxic at 13 mg/l, while liquid soap didn’t reach that threshold until 84 mg/l. For fish, the gap was even wider, with natural liquid soap showing no lethal effects until concentrations above 900 mg/l over two weeks.
Biodegradability tells a similar story. Natural soap compounds broke down at rates of 87 to 105% in standard OECD testing, while the synthetic detergent compound SDB (a close relative of SLS) showed essentially zero biodegradation at negative 3%. SLS itself biodegrades better than SDB, but the plant-based fatty acid soaps consistently outperform synthetic surfactants on environmental measures. Since Method uses SLS as a primary surfactant, its environmental profile is more moderate than a pure plant-oil soap, even though the rest of its formula leans greener.
Which Method Formulas Are Gentlest
If you want to stick with Method but minimize exposure to the most concerning ingredients, your best option is the Free + Clear line, which eliminates fragrance compounds and essential oils. Just be aware it still contains isothiazolinone preservatives. For people with sensitive skin or known allergies, checking the specific ingredient list for your exact product on EWG’s Skin Deep database or the brand’s own website is the most reliable approach, since formulations change between scents and between years.
Method hand soap is a reasonable choice for most households. It’s not toxic in any acute sense: you’re not going to poison yourself by washing your hands with it. But it does contain ingredients, particularly SLS and isothiazolinone preservatives, that can irritate or sensitize certain people’s skin with repeated use. Whether that qualifies as “non-toxic” depends on your personal threshold and whether you’re asking about human safety, environmental impact, or both.