Best Non-Toxic Toilet Bowl Cleaner in 2025


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Welpr Approved cleaning products are always free from:
- Harsh disinfectants and irritants: bleach, ammonia, sulfates, and quats
- Endocrine disruptors and preservatives: phthalates, parabens, BHA/BHT, triclosan
- Unnecessary additives: optical brighteners, artificial dyes, and synthetic fragrance (unless certified safe)
- Undisclosed or hidden ingredients
Common Harmful Chemicals in Toilet Bowl Cleaner
Chemical Name
Why it’s harmful
Hydrochloric acid is used in multiple industries like chlorides, fertilizers, dyes, electroplating, and others. It has dangerous health effects like irritation and inflammation of eyes, nose and respiratory tract, and pulmonary edema after short-term inhalation; corrosion to mucous membranes, esophagus, and stomach and severe burns after oral exposure; dermatitis, photosensitization, gastritis and chronic bronchitis after long-term occupational exposure. While the EPA hasn't classified hydrochloric acid for carcinogenicity, many chemicals can spill to release HCl in water.
Sodium laureth sulfate, derived from ethoxylated lauryl alcohol, is a surfactant used in sudsy products like toothpaste, detergents, and shampoos. While it acts as a cleansing and emulsifying agent, it can sometimes contain toxic impurities such as 1,4-dioxane. This chemical has raised health concerns due to its potential to cause skin, lung, and eye irritation, organ toxicity, and, primarily because of contamination by 1,4 dioxane, cancer.
The Dirty Dozen: Sodium Laureth Sulfate, 15 Toxic Trespassers, SKIP PRODUCTS MADE WITH SLES (AND SLS, TOO!), Campaign for Safe Costmetics: 1,4-DIOXANE, WHAT IS SODIUM LAURETH SULFATE: CHEMICAL FREE LIVING, A new formula for a mild body cleanser: sodium laureth sulphate supplemented with sodium laureth carboxylate and lauryl glucoside,
Sodium hydroxide, also known as caustic soda or lye, is an odorless white crystalline solid that absorbs moisture from the air. It generates significant heat when dissolved in water or neutralized with acid which may ignite combustible materials. It is highly corrosive and is typically used as a solid or in a 50% solution. Sodium hydroxide is used to manufacture a variety of products including soaps, rayon, paper, explosives, dyestuffs, and petroleum products. Exposure to this substance may cause severe burns, necrosis, and pulmonary edema, depending on the concentration and exposure method.
Sodium hypochlorite is a clear liquid with a strong chlorine odor, predominantly used as bleaching agents or disinfectants in commercial cleaning solutions and water purification systems. Sodium hypochlorite is often used in a dissolved state. It is corrosive to skin and can cause pulmonary edema from high inhalation exposure. Its ingestion can lead to methemoglobinemia, and a 3% to 5% solution causes burnings of the mouth and throat. The anhydrous form of this compound is highly explosive.
Sodium Lauryl Sulfate is recognised as a skin, eye, and respiratory tract irritant according to ICSC. It may cause allergic reactions and eye irritation as stated by the HSDB. Exposure may even result in eye burns, as per CAMEO. Depending on its form - which may range from a solid (90-98% purity), to a paste (30-41%), or an aqueous solution (28-50%) - it can significantly irritate skin and eyes, with adverse effects escalating with increased concentration. Despite these hazards, it is not a skin sensitizer according to CHEMINFO, while eChemPortal: ERMA and MSDSonline endorse its classification as an irritant.
Volatile organic compounds (VOCs) are released by many cleaning products, as revealed by a study in Chemosphere which analyzed 30 such items. Of the 530 distinct VOCs identified, 193 were considered hazardous, linked to health issues like respiratory system damage and cancer. Indoor air contamination from VOCs is significantly higher than outdoor, with up to 10 times more pollutants. However, products labeled as green, particularly those without fragrances, exhibited fewer hazardous VOC emissions. Exposure to VOCs has critical health implications, especially for cleaning industry workers and children, and these compounds also contribute to outdoor air pollution.
Phenol is a manufactured chemical and natural substance that is primarily used in the production of phenolic resins, nylon, and other synthetic fibers. It is also used in slimicides and various medicinal preparations. Exposure to phenol may occur from certain medicinal products and it can cause irritation to the skin, eyes, and mucous membranes, and toxicity when ingested. It can also lead to various health problems such as weight loss, vertigo, kidney damage, and other serious health conditions. It is highly corrosive, flammable, moderately soluble in water, and has a sweet, tar-like odor; it should be handled with protective clothing and stored in well-ventilated areas to avoid toxic exposure.
Phosphoric acid, in liquid or solid form, can cause second-degree burns upon contact within minutes. It's usually shipped as a solid or an 85% solution and is corrosive to skin when the concentration is over 70%. This acid is also an irritant to the eyes, skin, and upper respiratory tract, however, the risk of pulmonary edema is minimal.
Potassium hydroxide 30-70% is a liquid that is highly corrosive to skin, causing second or third-degree burns even after brief contact. It is a hazardous substance that can also induce pulmonary edema, a condition characterized by excessive fluid in the lungs. The effects and properties of this chemical can be compared to those of Sodium hydroxide.
Triethanolamine appears to cause occupational asthma and allergic contact dermatitis in machinists and photographers, as well as liver and kidney damage in animals with high-dose feeding. It's noted to be an irritant to the skin, eyes, and respiratory tract, with potential to cause skin sensitization, though the rate of skin sensitization in humans is low. Triethanolamine has low acute toxicity, with median oral LD50 values of 4,190-11,260 mg/kg in rats and 5,300-8,000 mg/kg in guinea pigs, and a median dermal LD50 greater than 2,000 mg/kg in rabbits. Triethanolamine is not carcinogenic, developmental toxicant, or toxic to the reproductive system. However, chronic exposure may lead to liver and kidney damage.
Safety assessment of triethanolamine and triethanolamine-containing ingredients as used in cosmetics, Toxicology of mono-, di-, and triethanolamine, Campaign for Safe Cosmetics: Ethanolamine Compounds (MEA, DEA, TEA And Others), The Dirty Dozen: DEA-related ingredients, Chemical Profile, Special Chem, Safety assessment of triethanolamine and triethanolamine-containing ingredients as used in cosmetics
2-Aminoethanol is a colorless, viscous liquid that, despite not being registered for pesticide use in the U.S, holds vast potential in a variety of applications. It can be used in cutting fluids, production of soaps, surfactants, salts, corrosion control inhibitors, pharmaceuticals, and even in protective topical solutions against chemical warfare agents. Used as a pharmaceutical adjuvant, 2-Aminoethanol is effective as a solvent for fats and oils and in creating emulsion formulas like lotions and creams. However, it poses health risks, as a 5.9% concentration can irritate human skin and inhalation may cause allergic reactions, liver damage, and liver symptoms.
Ethanolamine is a liquid that can cause first-degree burns on short exposure. It is known to be a skin irritant and can cause allergic contact dermatitis. Occupational exposure, notably among hairdressers, has been linked to asthma. Inhalation of ethanolamine in high concentrations can lead to Central Nervous System (CNS) depression and can be toxic to the liver, as shown in subchronic inhalation studies in animals. It is also a skin, eye, and respiratory tract irritant, with the potential to sensitize the skin.
Diethanolamine is a chemical found in various consumer products like shampoos, cosmetics, and pharmaceuticals. Acute exposure in humans can result in irritation of the nose, throat, and skin. However, no detailed data is available on its chronic, reproductive, developmental or carcinogenic effects on humans. Studies on animals reveal that acute oral exposure can influence the liver, blood, kidney, and central nervous system, while dermal exposure has been connected with an increased incidence of liver and kidney tumors in mice. Production of first-degree burns, skin irritation, occupational asthma, kidney, and liver injury risk, and potential skin sensitization are some other adverse effects associated with diethanolamine.
Chemical Safety Facts: Ethanolamines, NTP Toxicology and Carcinogenesis Studies of Diethanolamine, California Environmental Protection Agency: Diethanolamine , International Agency for Research on Cancer: Diethanolamine, Initial List of Hazardous Air Pollutants with Modifications, What is the Toxics Release Inventory?, OPINION CONCERNING DIALKYL- AND DIALKANOLAMINES AND THEIR SALTS IN COSMETIC PRODUCTS, Ethanolamine Compounds (MEA, DEA, TEA And Others), WHAT ARE ETHANOLAMINE COMPOUNDS (DEA, MEA, OR TEA): CHEMICAL FREE LIVING, The Dirty Dozen: DEA-related ingredients, FDA: Diethanolamine, Chemical Profile: Diethanolamine ,
Benzyl alcohol can occasionally lead to allergic contact dermatitis or occupational contact urticaria. It can irritate the skin and eyes, and inhalation at high quantities can result in central nervous system effects. Rats exposed to high concentrations showed no deaths, however, it has caused fatalities in premature infants when given in IV solutions at doses over 4.5mg/kg a day. The substance is quickly metabolized to hippuric acid and is noted as a known contact allergen in humans.
Sodium Dichloroisocyanurate is toxic upon ingestion and act as a strong oxidizer, posing a fire hazard when exposed to organic materials. It may react violently with combustible substances and decompose due to heat or water, releasing toxic gases such as chlorine. It can cause irritation to the skin, eyes and respiratory tract, and prolonged exposure can result in corrosive skin burns. Inhalation of high concentrations can lead to acute pulmonary edema. It may also explode from shock, friction, or other ignition sources, and can cause fires upon contact with combustible materials.
Ethylene oxide is a flammable, sweet-smelling gas that easily dissolves in water. This man-made compound is primarily used to create ethylene glycol, which is used to make antifreeze and polyester, and is also used in small quantities for controlling insects in stored agricultural products, sterilizing medical equipment and fumigating spices. Ethylene oxide may cause irritation of the eyes, skin, nose, throat, and lungs, damage to the brain and nervous system, reproductive effects, and is considered by the EPA to be carcinogenic if inhaled. Exposure risks, which are notably prevalent for healthcare workers engaged in sterilization tasks, include CNS depression, eye and mucous membrane irritation and in some cases, cataracts. Despite these hazards, there are conflicted reports regarding ethylene oxide's carcinogenicity in humans.
Ethylene oxide derived glycol ethers: A review of the alkyl glycol ethers potential to cause endocrine disruption, Adverse health effects of ethylene oxide and occupational exposure limits, Campaign For Safe Cosmetics: Ethoxylated Ingredients, Ingredient Breakdown: ETHYLENE OXIDE, Ethylene Oxide Overview, What is Ethylene Oxide?, Ethylene Oxide Hazard Summary, FDA Authority Over Cosmetics: How Cosmetics Are Not FDA-Approved, but Are FDA-Regulated, DEFINE ETHOXYLATES OR ETHOXYLATED SURFACTANT AND ITS APPLICATIONS?, Known and Probable Human Carcinogens, OSHA Fact Sheet
Glycolic Acid is corrosive to the skin and eyes, with 70% technical solutions causing severe burns. It also irritates the respiratory tract and may lead to kidney failures. The chemical can cause burns when inhaled, leading to possible injuries to the upper respiratory tract and lungs. It is also harmful if ingested.
Laureth-7, a surfactant derived from lauryl alcohol sourced from coconut or palm oil, is commonly used in personal care and household products, especially laundry detergents. In detergents, it functions by reducing surface tension between water and soil, aiding in the removal of dirt, stains, and oils from fabrics. This ingredient belongs to the Polyethylene Glycols (PEGs) family, which is found in various consumer goods. Despite past contamination concerns, modern manufacturing processes have addressed and eliminated these issues. Although PEGs are not used in certain personal care products, their inclusion in machine detergents is deemed acceptable since they don't directly touch the skin.
d-Limonene is a liquid with a lemon-like smell, often used as a solvent to substitute for more volatile and toxic organic solvents. When it comes into contact with air, it can oxidize, and this oxidized form is a known skin sensitizer, capable of irritating skin and eyes. The combination of d-limonene and l-limonene is known as limonene or dipentene. The estimated lethal dose for humans is between 0.5 to 5 g/kg, and studies have shown that it can cause diarrhea and liver effects when ingested in high doses.
Linalool is a naturally occurring terpene alcohol found in many flowers and spice plants, consisting of two enantiomers. It is widely used in commercial products for its pleasant floral and spicy scent, serving as a key ingredient in soaps, fragrances, food flavors, household products, and insecticides. In plants, linalool functions as a metabolite, volatile oil component, antimicrobial agent, and aroma compound. Acute exposure to linalool can lead to central depressive effects with symptoms such as ataxia, reduced motor activity, and respiratory disturbances. Additionally, inhalation, oral intake, or skin absorption can result in irritation, pain, and allergic reactions.






