The Welpr Rating is determined by a scoring formula. The formula takes into account the products safety, user satisfaction, and eco-ethical standing. Click here to learn more.
Best Non-Toxic Hair Straightener & Smoothing Treatment in 2024
Updated:
Nov 18, 2024
Written by Camille May
Cofounder & Product Curator
+ 1 more
Medically reviewed by Olushola Awoyemi
PhD Environmental Toxicology
As an Amazon Associate, we earn from qualifying purchases. Our use of affiliate links does not influence how we rate products. Learn more about our affiliate policy here.
What you should know when choosing non-toxic hair straighteners & smoothing treatments on Welpr:
- Only the cleanest products make it onto Welpr.
- We use a score called the Welpr Rating to rank each product.
- The Welpr Rating is based on math, not opinion, ensuring it's free from human bias.
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Find Non-Toxic Hair Straightener & Smoothing Treatment
Third-party certifications are key indicators of a product's safety, ethics, and environmental impact. Click the icon to verify the certification.
Highlights aren't always verifiable, so you're trusting the brand when they say "lead free", etc. If the highlight icon is "clickable", it means we've verified the highlight.
User satisfaction is calculated using online reviews and a Bayesian average across all personal care and cosmetic products on Welpr.
Keratin Smooth Hair Mask - Luseta
Highlights
User Satisfaction
Est. Price
$17.79
Product Details
- Infused with keratin, designed for damaged and dry hair.
- Moisturizing and repairing formula promotes growth and health.
- Provides deep nourishment for softer locks.
- Protects hair from environmental damage.
- Safe for colored hair.
- Free of sulfates, parabens, and gluten.
- Use recommendation: After shampooing, apply generously to damp hair, leave for up to 5 minutes, then rinse. For best results, use weekly.
- Not tested on animals.
Pros & Cons
Pros Mentioned
- Hydrating
- Softening
- Shiny
Cons Mentioned
- Frizzy
Ingredients
Ingredients can vary by product variation and may change at any time by the manufacturer. For the most complete and up-to-date list of ingredients, refer to the product packaging.
To analyze individual ingredients, use INCIDecoder.
Ingredients: Water (Aqua, Eau), Cetearyl Alcohol, Steartrimonium Chloride, Dimethicone, Amodimethicone, Parfum, Dimethiconol, Benzyl Alcohol, Trideceth-12, Hydrolyzed Keratin, Phenoxyethanol, Cetrimonium Chloride, Sodium Benzoate, Alcohol, Tetrasodium Edta, Cetyl Hydroxyethylcellulose, Citric Acid, Chenopodium Quinoa Seed Extract, Cocodimonium Hydroxypropyl Hydrolyzed Keratin, Butylene Glycol, Potassium Sorbate
Third-party certifications are key indicators of a product's safety, ethics, and environmental impact. Click the icon to verify the certification.
Highlights aren't always verifiable, so you're trusting the brand when they say "lead free", etc. If the highlight icon is "clickable", it means we've verified the highlight.
User satisfaction is calculated using online reviews and a Bayesian average across all personal care and cosmetic products on Welpr.
LOVE Hair Smoother - Davines
Certifications
Highlights
User Satisfaction
Est. Price
$31.00
Pros & Cons
Pros Mentioned
- Smooth
- Scent
- Manageable
Cons Mentioned
- Overpowering
Ingredients
Ingredients can vary by product variation and may change at any time by the manufacturer. For the most complete and up-to-date list of ingredients, refer to the product packaging.
To analyze individual ingredients, use INCIDecoder.
Ingredients: Aqua / Water / Eau, Dimethicone, Propylene Glycol, Cyclopentasiloxane, Disiloxane, Phenylpropyldimethylsiloxysilicate, Glycerin, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Benzyl Alcohol, Cyclohexasiloxane, Polyacrylamidomethylpropane Sulfonic Acid, Simmondsia Chinensis Seed Oil / Simmondsia Chinensis (Jojoba) Seed Oil, Panthenol, Ethylhexyl Methoxycinnamate, Polyquaternium-28, Parfum / Fragrance, Triethanolamine, Dicaprylyl Ether, Dimethiconol, Lauryl Alcohol, Disodium EDTA, Buteth-3, Sodium Benzoate, Sclerotium Gum, Creatine, Olea Europaea Fruit Extract / Olea Europaea (Olive) Fruit Extract, Sodium Benzotriazolyl Butylphenol Sulfonate, Mica, CI 77891 / Titanium Dioxide, Caprylyl Glycol, Phenoxyethanol, Limonene, Alcohol, Tributyl Citrate, Citric Acid, Tris(Tetramethylhydroxypiperidinol) Citrate, CI 60730 / Ext Violet 2, CI 19140 / Yellow 5, CI 14700 / Red 4
Third-party certifications are key indicators of a product's safety, ethics, and environmental impact. Click the icon to verify the certification.
Highlights aren't always verifiable, so you're trusting the brand when they say "lead free", etc. If the highlight icon is "clickable", it means we've verified the highlight.
User satisfaction is calculated using online reviews and a Bayesian average across all personal care and cosmetic products on Welpr.
Silk Smoothing Balm With Keratin, Hydrolyzed Silk & Coconut Oil - Pure Brazilian
Highlights
User Satisfaction
Est. Price
$30.00
Product Details
- Rich lightweight formula controls and softens unruly hair.
- Helps hair achieve a silky, straight style.
- Protects hair from frizz caused by humidity.
- Provides a natural, sleek shine.
- Leaves hair with natural moisture and softness.
- Heat and humidity-resistant, ensuring hair remains light and bouncy.
- Regular use before styling makes hair faster drying and more manageable.
- Reduces tangles and frizz while improving hold and smoothness.
- Designed for at-home maintenance of salon treatments or standalone use.
Pros & Cons
Pros Mentioned
- Shiny
- Soft
- Fresh-scented
Cons Mentioned
- Volume-reducing
Ingredients
Ingredients can vary by product variation and may change at any time by the manufacturer. For the most complete and up-to-date list of ingredients, refer to the product packaging.
To analyze individual ingredients, use INCIDecoder.
Ingredients: Aqua (Water/Eau), Dimethicone, Cyclopentasiloxane, Propylene Glycol, Dimethiconol, Phenyl Trimethicone, Phenoxyethanol, PEG-12 Dimethicone, Polyacrylamide, Parfum (Fragrance), PPG-2 Myristyl Ether Propionate, Aloe Barbadensis Leaf Juice, Panthenol, C13-14 Isoparaffin, Hydrolyzed Silk, Hydrolyzed Keratin, Keratin Amino Acids, Pearl Powder, Tocopheryl Acetate, Laureth-7, Cocos Nucifera (Coconut) Oil, Ricinus Communis (Castor) Seed Oil, Coumarin, Geraniol, Butylphenyl Methylpropional, Linalool, Hexyl Cinnamal, Limonene, Alpha-Isomethyl Ionone
Third-party certifications are key indicators of a product's safety, ethics, and environmental impact. Click the icon to verify the certification.
Highlights aren't always verifiable, so you're trusting the brand when they say "lead free", etc. If the highlight icon is "clickable", it means we've verified the highlight.
User satisfaction is calculated using online reviews and a Bayesian average across all personal care and cosmetic products on Welpr.
Smoothing Hair Treatment - Grown Alchemist
Certifications
User Satisfaction
Est. Price
$33.00
Product Details
- Formulated to smooth hair, eliminate flyaways, and protect against damage from heat styling.
- Enhances natural hair appearance, leaving it silky smooth and hydrated.
- Enriched with Hydrolyzed Milk Protein and Pro-Vitamin A to increase styling manageability and provide essential nutrients to the hair follicle.
- Contains Cationic Guar Gum that smooths and detangles hair without build-up.
- Includes Edelweiss Extract and Sambucus which condition the scalp and increase hair health, visibly smoothing and conditioning the hair.
- Formulated with plant-derived Liposomes that optimize the delivery of actives for healthier, smoother hair.
- Recommended for use after straightening iron or other heat styling tools.
- Part of Grown Alchemist’s organic, non-toxic, vegan, and cruelty-free product line.
Pros & Cons
Pros Mentioned
- Soft
- Beautiful
- Morbidi
Cons Mentioned
- Dry
Ingredients
Ingredients can vary by product variation and may change at any time by the manufacturer. For the most complete and up-to-date list of ingredients, refer to the product packaging.
To analyze individual ingredients, use INCIDecoder.
Ingredients: Aqua/Water/Eau, Behentrimonium Methosulfate (*Plant), Decyl Oleate (*Plant), Sodium Lactate (*Plant), Lactic Acid (*Plant), Sodium Chloride, Glycerin (*Plant), Levulinic Acid, P-Anisic Acid (*Plant), Cetyl Alcohol (*Plant), Camellia Oleifera Seed Oil, Cetearyl Alcohol (*Plant), Behentrimonium Chloride (*Plant), Starch Hydroxypropyltrimonium Chloride (*Plant), Aloe Barbadensis Leaf Extract, Urea, Leontopodium Alpinum (Edelweiss) Extract (*Plant), Sambucus Nigra (Elderberry) Fruit Extract (*Plant), Panthenol (Pro-Vitamin B5) (*Plant), Cetrimonium Chloride (*Plant), Benzyl Alcohol, Dehydroacetic Acid, Beta Carotene (Provitamin A/Provitamine A), (*Plant), Citrus Clementina (Clementine) Peel Oil, Pogostamon Cablin (Patchouli) Leaf Oil, Polianthes Tuberosa (Tuberose) Flower Oil, Cananga Odorata (Ylang Ylang) Flower Oil, Cedrus Atlantica (Cedarwood) Wood Oil, Benzyl Benzoate (*Plant/Plante), Geraniol (*Plant), Linalool (*Plant), Limonene (*Plant) (*Plant Derived)
Third-party certifications are key indicators of a product's safety, ethics, and environmental impact. Click the icon to verify the certification.
Highlights aren't always verifiable, so you're trusting the brand when they say "lead free", etc. If the highlight icon is "clickable", it means we've verified the highlight.
User satisfaction is calculated using online reviews and a Bayesian average across all personal care and cosmetic products on Welpr.
Keratin Smoothing Masque Packette - Ion
User Satisfaction
Est. Price
$24.97
Pros & Cons
Pros Mentioned
- Smoothing
- Detangling
- Softening
Ingredients
Ingredients can vary by product variation and may change at any time by the manufacturer. For the most complete and up-to-date list of ingredients, refer to the product packaging.
To analyze individual ingredients, use INCIDecoder.
Ingredients: Water, Dimethicone, Cetearyl Alcohol, Behentrimonium Chloride, Vegetable Oil, Sorbitol, Cetyl Esters, Stearyl Alcohol, Glycol Stearate, Fragrance, Hydroxyethylcellulose, Hydrolyzed Keratin, Ceteareth-20, Guar Hydroxypropyltrimonium Chloride, DMDM Hydantoin, Disodium EDTA, Citric Acid, Iodopropynyl Butylcarbamate, Pyridoxine HCL, Panthenol, Prunus Amygdalus Dulcis (Sweet Almond) O, Biotin, Hexyl Cinnamal, Linalool
Third-party certifications are key indicators of a product's safety, ethics, and environmental impact. Click the icon to verify the certification.
Highlights aren't always verifiable, so you're trusting the brand when they say "lead free", etc. If the highlight icon is "clickable", it means we've verified the highlight.
User satisfaction is calculated using online reviews and a Bayesian average across all personal care and cosmetic products on Welpr.
Express Blonde Keratin Smoothing Treatment - Cezanne
User Satisfaction
Est. Price
$184.99
Product Details
- Smoothing and strengthening treatment for all hair types
- Formaldehyde-free formula, gentle and safe for sensitive skin
- Unisex formula, suitable for both men and women's hair
- Contains keratin to restore elasticity and manage frizz
Ingredients
Ingredients can vary by product variation and may change at any time by the manufacturer. For the most complete and up-to-date list of ingredients, refer to the product packaging.
To analyze individual ingredients, use INCIDecoder.
Ingredients: Water (Aqua) (Eau), Glyoxylic Acid, Propylene Glycol, Shea Butter Cetyl Esters, Distearoylethyl Dimonium Chloride, Argania Spinosa Kernel Oil*, Theobroma Cacao (Cocoa) Seed Butter, Alcohol Denat., Aloe Barbadensis Leaf Juice*, Cetearyl Alcohol, Cetyl Alcohol, Stearyl Alcohol, Methyl Gluceth-10, Silk Amino Acids, Hydrolyzed Keratin, Xanthan Gum, Propylene Glycol Dicaprylate/Dicaprate, Quaternium-87, Polyquaternium-37, Polyquaternium-47, PPG-1 Trideceth-6, Polyquaternium-67, PEG-180M, Trideceth-12, Cetrimonium Chloride, Silica, Butylene Glycol, Amodimethicone, BHT, Phenoxyethanol, Ethylhexylglycerin, Potassium Sorbate, Sodium Benzoate, Fragrance (Parfum), Benzyl Salicylate, Benzyl Alcohol, Ext. Violet 2 (CI 60730)
Third-party certifications are key indicators of a product's safety, ethics, and environmental impact. Click the icon to verify the certification.
Highlights aren't always verifiable, so you're trusting the brand when they say "lead free", etc. If the highlight icon is "clickable", it means we've verified the highlight.
User satisfaction is calculated using online reviews and a Bayesian average across all personal care and cosmetic products on Welpr.
a-Keratin Smoothing And Refinishing Treatment - Peter Coppola
Highlights
User Satisfaction
Est. Price
$71.99
Product Details
- Quickly removes frizz and strengthens hair.
- Formulated to provide smoother, stronger, age-defying hair.
- Nourishes, repairs, and shields hair from processing, heat styling, UV exposure, and daily styling damage.
- Safely smooths hair and improves appearance and manageability for up to three months.
- Infuses keratin proteins and enriched with shea butter for strong, smooth, and healthy hair.
- Free from formaldehyde, aldehydes, parabens, gas byproducts, and non-carcinogenic.
- Reduces frizz and curls, leaving hair soft, silky, and manageable for up to 3 months.
- Changes the texture of all hair types allowing for a variety of styles.
- Restores damaged hair to healthy, youthful appearance.
- Creates a barrier for thermal protection against various hair damages.
Pros & Cons
Pros Mentioned
- Effective
- Easy
- Natural
Cons Mentioned
- Smell
Ingredients
Ingredients can vary by product variation and may change at any time by the manufacturer. For the most complete and up-to-date list of ingredients, refer to the product packaging.
To analyze individual ingredients, use INCIDecoder.
Ingredients: Aqua, Silicone Quaternium-16/Glycidoxy Dimethicone Crosspolymer, Undeceth-11, Undeceth-5, 1,3-Butylene Glycol, Polyquaternium-37, Propylene Glycol Dicaprylate/Dicaprate, PPG-1 Trideceth-6, PEG-12 Dimethicone, Caprylyl Glycol, Phenoxyethanol, Hexylene Glycol, Glycereth-26, Panthenol, Parfum, Keratin, Hydrolyzed Keratin, Aloe Barbadensis Leaf Extract, Glycerin, Saccharum Officinarum Extract, Malva Sylvestris Flower Extract, Cystoseira Compressa Extract, Urtica Dioica Leaf Extract, Yucca Schidigera Root Extract, Equisetum Arvense Extract, Melissa Officinalis Leaf Extract, Chenopodium Quinoa Seed Extract, Cocos Nucifera Oil, Argania Spinosa Kernel Oil, Hydrolyzed Wheat Protein, Olea Europaea Fruit Oil, Benzyl Salicylate, Limonene, Linalool, Citronellol
Third-party certifications are key indicators of a product's safety, ethics, and environmental impact. Click the icon to verify the certification.
Highlights aren't always verifiable, so you're trusting the brand when they say "lead free", etc. If the highlight icon is "clickable", it means we've verified the highlight.
User satisfaction is calculated using online reviews and a Bayesian average across all personal care and cosmetic products on Welpr.
Smoothing Keratin Hair Treatment - GK Hair
User Satisfaction
Est. Price
$64.90
Product Details
- Rejuvenates hair making it smooth, strong, and frizz-free with results lasting 3-5 months.
- Can be applied at home or in a salon setting.
- Utilizes natural seed oils for natural hair smoothing and repairing damage from within.
- Includes necessary products such as GK Hair pH+ Clarifying Shampoo, The Best Keratin Treatment, Moisturizing Shampoo, Moisturizing Conditioner, and a Deep Conditioner sachet.
- No waiting time required after application before washing hair again.
- Reduces natural curl pattern and closes hair cuticle to eliminate frizz.
- Formulated with Juvexin, an anti-aging keratin protein that provides hair protection and moisture, enhancing shine and vitality.
- Contains enriching natural ingredients like Pentaclethra seeds, Astrocaryum murumuru, and coconut for nourishment and moisture retention.
- Included step-by-step application guide ensures optimal product effectiveness.
- After treatment, clients may wash their hair at any time using GKHair Shampoos and Conditioners to maintain treatment results.
Pros & Cons
Pros Mentioned
- Moisturizing
- Manageable
- Easy
Cons Mentioned
- Frizzy
Ingredients
Ingredients can vary by product variation and may change at any time by the manufacturer. For the most complete and up-to-date list of ingredients, refer to the product packaging.
To analyze individual ingredients, use INCIDecoder.
Ingredients: Aqua, Glyoxylic Acid, Glyceryl Stearate SE, Propylene Glycol, Behentrimonium Chloride, Cetyl Alcohol, Paraffinum Liquidum, Cetrimonium Chloride, Cetearyl Alcohol, Polysorbate 60, Glycerin, Potassium Stearate, Isopropyl Alcohol, Lycium Barbarum Fruit Extract, Myristyl Alcohol, Panthenol, Hydrolyzed Rice Protein, Copaifera Officinalis Resin, Creatine, Dimethicone, Cera Alba, Argania Spinosa Kernel Oil, Tocopheryl Acetate, Stearamidopropyl Dimethylamine, Hydrolyzed Silk, Hydrolyzed Wheat Protein, Cocos Nucifera Oil, Disodium EDTA, Benzotriazolyl Dodecyl P-Cresol, Octadecyl Di-T-Butyl-4-Hydroxyhydrocinnamate, Hydrolyzed Keratin, Oxidized Keratin, Keratin (Hydrolyzed Keratin), Sodium PCA, Sodium Lactate, Arginine, Aspartic Acid, PCA, Gardenia Taitensis Flower, Glycine, Alanine, Stearic Acid, Serine, Valine, Threonine, Proline, Isoleucine, Histidine, Phenylalanine, Amyl Cinnamal, Benzyl Benzoate, Benzyl Salicylate, Butylphenyl Methylpropional, Citronellol, D-Limonene, Hexyl Cinnamal, Linalool
Our Product Rating System
First, Camille (co-creator of Welpr) hand picks cleaner product options from a variety of sources.
Next, we collect information about each product's safety, consumer satisfaction, and eco-ethical standing.
Finally, we run all this information through an algorithm that calculates the Welpr Rating.
Welpr Rating:
5.0/5
Part 1: Product safety
We evaluate safety information from 3rd party organizations (e.g. EWG, Made Safe, etc.). Instead of relying solely on any one of these companies for safety information, we assess all of them.
Part 2: Consumer satisfaction
We scour the web for consumer ratings and reviews to verify products are not only cleaner options, but also effective. Products can either be Above Average, Average, or Below average for their respective category (e.g. cleaning products).
Part 3: Ethics & Environment
When you buy a product, you’re supporting that company with your dollars. We believe it’s important to support ethical companies, so we pool together certifications that verify a company's ethics and environmental impact.
Common Harmful Chemicals in Hair Straightener & Smoothing Treatment
Chemical Name
Why it’s harmful
Phthalate
Phthalates, linked to endocrine disruption, reproductive toxicity, and cancer, are banned in the European Union but remain prevalent in U.S. cosmetics. They are widely used in personal care products, such as nail polish, fragrances, and eyelash glue and other products. A significant loophole allows phthalates to be added to fragrances without disclosure. Health concerns include endocrine disruption, developmental and reproductive toxicity, and potential carcinogenicity.
Sources:
Campaign for Safe Cosmetics: Phthalates, Product Profile: Hand Sanitizer, Phthalates in Cosmetics, Phthalates in cosmetic and personal care products: concentrations and possible dermal exposure, A Survey of Phthalates and Parabens in Personal Care Products from the United States and Its Implications for Human Exposure, Phthalates Factsheet, BPA and Phthalates: Chemicals found in our homes
Sodium Laureth Sulfate
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.
Sources:
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 Lauryl Sulfate
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.
Triclosan
Triclosan is a synthetic pesticide with antibacterial properties commonly added to detergents, soaps, and various personal care products such as deodorants and toothpastes. Although it lacks the ability to combat viruses causing colds and flus, it's used in products like body washes, disinfectants, and some toothpastes to resist bacterial growth. In 2016, the FDA limited its use in antibacterial soaps, but the compound is still permitted in other products. The European Union prohibited its presence in food-contact items in 2010. Exposure to triclosan has been associated with hormone disruption, increased breast cancer risk, liver damage, and the development of resistant super-germs.
Sources:
Triclosan Exposure, Transformation, and Human Health Effects, Are antibacterial products with triclosan fueling bacterial resistance?, Antimicrobial agents, triclosan, chloroxylenol, methylisothiazolinone and borax, used in cleaning had genotoxic and histopathologic effects on rainbow trout, The Effects of Triclosan on Puberty and Thyroid Hormones in Male Wistar Rats, Triclosan is a potent inhibitor of estradiol and estrone sulfonation in sheep placenta, The in Vitro estrogenic activities of triclosan and triclocarban, Antibacterial Soap? You Can Skip It, Use Plain Soap and Water, Environmental Exposure of Aquatic and Terrestrial Biota to Triclosan and Triclocarban, Triclosan: Environmental Fate and Effects, Chemical Profile: Triclosan / Triclocarban, 5 Things to Know About Triclosan, Underarm Harm? Whats So Bad About Antiperspirants?, Some flame retardants and the antimicrobials triclosan and triclocarban enhance the androgenic activity in vitro, Triclocarban Enhances Testosterone Action: A New Type of Endocrine Disruptor?, Triclosan, a commonly used bactericide found in human milk and in the aquatic environment in Sweden
Benzene
Benzene is a colorless, sweet-smelling, highly flammable liquid that evaporates quickly into the air and slightly dissolves in water. It's a byproduct of both natural processes and human activities, used extensively in the U.S production of other chemicals for plastics, resins, nylon, rubbers, lubricants, dyes, detergents, drugs, and pesticides. Present in crude oil, gasoline, and cigarette smoke, benzene is also released into the air from burning coal, oil, gasoline stations, and vehicle exhaust. Short-term exposure may cause drowsiness, dizziness, and irritation, while long-term exposure leads to blood disorders, reproductive effects, and even leukemia. Benzene has been classified by EPA as a known human carcinogen, and regulations apply to various industry sectors with potentially high exposure risks.
Sources:
Triethanolamine
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.
Sources:
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
Diethanolamine
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.
Sources:
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 ,
Phenoxyethanol
2-Phenoxyethanol is a hazardous substance toxic by all routes of exposure, and is used widely in products like cosmetics, soaps, and inks, among others. The effects of exposure to this faintly aromatic, colorless, oily liquid can include eye irritation, headaches, tremors, and CNS depression. It's crucial to rinse exposed eyes with tepid water for at least 15 minutes and to wash exposed skin thoroughly with soap and water in case of contact. The substance requires preheating before ignition can occur, and if involved in a fire, gentle water spray can extinguish the fire by inducing frothing.
Methylisothiazolinone
Methylisothiazolinone can reportedly cause allergic contact dermatitis in workers who interact with products containing it. This substance is recognized as a contact allergen for consumers using cosmetics that include it. It can cause skin burns and sensitization, and inhaling it may lead to corrosive injuries in the upper respiratory tract and lungs. Ingesting this substance is harmful, and inhalation is toxic. This preservative is linked to the category of isothiazolinones.
Sources:
Antimicrobial agents, triclosan, chloroxylenol, methylisothiazolinone and borax, used in cleaning had genotoxic and histopathologic effects on rainbow trout, Methylisothiazolinone toxicity and inhibition of wound healing and regeneration in planaria, Methylchloroisothiazolinone and/or methylisothiazolinone in cosmetic products, Isothiazolinone Biocides: Chemistry, Biological, and Toxicity Profiles, Methylisothiazolinone and isothiazolinone allergy, Analysis of isothiazolinones in environmental waters by gas chromatography–mass spectrometry, Methylisothiazolinone induces apoptotic cell death via matrix metalloproteinase activation in human bronchial epithelial cells, EU REGULATIONS , Methylisothiazolinone contact allergy: a review, Effects of methylisothiazolinone and octylisothiazolinone on development and thyroid endocrine system in zebrafish larvae, Two Cases of Chloromethylisothiazolinone and Methylisothiazolinone-associated Toxic Lung Injury, An update of the risk assessment for methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) with focus on rinse-off products, Effects of a mixture of chloromethylisothiazolinone and methylisothiazolinone on peripheral airway dysfunction in children, Isothiazolinone preservative: cause of a continuing epidemic of cosmetic dermatitis, Campaign for Safe Cosmetics: Methylisothiazolinone and Methylchloroisothiazolinone
Isopropyl Alcohol
Isopropyl alcohol has been shown to cause narcosis in animals during acute studies, as cited by ACGIH. However, according to research by Zimmerman, it is not hepatotoxic in either experimental animal studies or in human exposures. It's known to be a skin, eye, and respiratory tract irritant, and if inhaled in high concentrations, it can cause CNS depression, as indicated by the ICSC.
Octinoxate
Octinoxate, commonly found in various cosmetic and personal care products such as hair color products, sunscreen, lipstick, and skin creams, is an endocrine disruptor that mimics estrogen and can affect thyroid function. It has been detected in human urine, blood, and breast milk, indicating systemic exposure. Octinoxate's potential health concerns include its impact on cell proliferation in response to estrogen exposure, disruptions in thyroid hormones, alterations in reproductive systems, and adverse effects on the development of male and female fetuses, as well as their offspring.
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