Ingredient
Basic Red 46
Basic Red 46 is flagged for pregnancy, breastfeeding, postpartum, trying to conceive and general use. The concern behind the strongest flag is absorbed into the body and fetal development.
- CI 12355
- Basic Red 46:1
Verdict by profile
Truva checks every ingredient against six profiles. Jump to any of them for the full assessment.
- Strongest verdict
- Not Recommended
- Its verdict for pregnancy, the profile this one is worst in
- Profiles flagged
- 5 of 6
- Counting avoid, high risk and medium risk
- Irritancy
- 3 of 5
- Higher means more likely to sting or redden
Basic Red 46 and pregnancy
Not Recommended
- Absorbed into the body
- Fetal development
Basic Red 46 is a synthetic azo dye used primarily in hair coloring products to produce red and violet tones. Azo dyes are a class of synthetic colorants that have raised safety concerns due to their chemical structure and potential for metabolic breakdown into potentially harmful compounds. While not absolutely prohibited during pregnancy like some ingredients, most obstetricians and dermatologists advise against using hair dyes containing synthetic azo dyes during pregnancy, particularly in the first trimester. The concern stems from the potential for systemic absorption through the scalp, especially with damaged or irritated skin, and the theoretical risk of metabolites crossing the placental barrier. The EU restricts Basic Red 46 to 0.5% concentration in non-oxidative hair dyes with mandatory warning labels due to sensitization concerns, and these same concerns extend to pregnancy. ACOG states that hair dye use during pregnancy is a controversial topic, with many providers recommending postponing chemical hair treatments until after the first trimester when organogenesis is complete, or avoiding them entirely. If hair coloring is desired during pregnancy, dermatologists typically recommend semi-permanent vegetable-based dyes or highlighting techniques that minimize scalp contact. Safer alternatives for pregnancy include henna, vegetable-based dyes, or postponing hair coloring.
Basic Red 46 and breastfeeding
Caution Advised
- Absorbed into the body
Basic Red 46 is a synthetic hair dye colorant restricted by the EU to specific concentrations due to sensitization concerns. When used in hair dye applications, there is potential for scalp absorption, particularly if the scalp is irritated or the product is left on for extended periods. While specific data on transfer to breast milk is limited, synthetic azo dyes can be systemically absorbed to some degree. Most dermatologists take a cautious approach with synthetic hair dyes during breastfeeding, especially those requiring warning labels. The concern is less acute than during pregnancy since the dye doesn't cross the placental barrier, but systemic absorption and potential milk transfer remain theoretical considerations. Many healthcare providers suggest that if hair coloring is desired during breastfeeding, waiting until after the early months (when infant is most vulnerable) and choosing less aggressive coloring methods like highlights or semi-permanent vegetable-based dyes may be preferable. If using products with Basic Red 46, ensure good ventilation, avoid leaving on longer than necessary, and rinse thoroughly.
Basic Red 46 and postpartum
Caution Advised
Basic Red 46 is a restricted synthetic hair dye that requires EU warning labels due to sensitization potential. Without the additional concern of breastfeeding, the primary risks are allergic reactions and skin irritation. The EU allows this dye in non-oxidative hair products up to 0.5% with mandatory allergy warnings. If using products containing this ingredient, professional patch testing is strongly recommended, especially if you have sensitive skin or a history of allergies. Follow all product warnings and do not exceed recommended application times.
Basic Red 46 and trying to conceive
Caution Advised
- Builds up in tissue
Basic Red 46 is a synthetic azo dye used in hair coloring. When trying to conceive, many healthcare providers recommend minimizing exposure to synthetic chemicals with uncertain reproductive safety profiles, following the precautionary principle. While there's no definitive evidence that this specific dye affects fertility, synthetic azo dyes as a class have raised some safety concerns. Most fertility specialists suggest transitioning to safer alternatives during the preconception period, especially since you'll want to avoid these products once pregnant. Consider switching to plant-based or semi-permanent coloring options as you prepare for conception.
Basic Red 46 and PCOS
Safe to Use
Basic Red 46 is a synthetic colorant used in hair dyes. It has no known hormonal activity or effects on androgen metabolism, making it generally acceptable for women with PCOS from an endocrine perspective. The primary concerns with this ingredient are allergic reactions and skin sensitization rather than hormonal effects. The EU restricts its concentration and requires warning labels due to sensitization potential. Women with PCOS can use products containing this dye if they tolerate it well, though patch testing is recommended. If you have PCOS-related skin sensitivity or inflammatory conditions, the irritation potential of this dye may be a consideration. Choose products following EU concentration limits and always perform patch tests before full application.
Basic Red 46 and general use
Caution Advised
- Common allergen
Basic Red 46 (CI 12355) is a synthetic azo dye used primarily in non-oxidative hair coloring products to achieve red and violet tones. Azo dyes are a large class of synthetic colorants known for their vibrant colors but also for their potential to cause allergic reactions. The European Union restricts Basic Red 46 to a maximum concentration of 0.5% in non-oxidative hair dye products, and products containing it must carry specific warning labels about potential allergic reactions. The restriction exists because this dye can cause contact dermatitis and sensitization in some individuals. Professional patch testing is strongly recommended before use, especially for those with sensitive skin or a history of dye allergies. While permitted for use within restrictions, consumers should be aware of the sensitization potential. Always follow product instructions, perform patch tests 48 hours before application, and do not exceed recommended processing times. If irritation occurs, discontinue use immediately. Those with sensitive skin may prefer alternative colorants with better tolerability profiles.
Everything else flagged for the same profiles
Related ingredients
Ingredients suggested in place of Basic Red 46, each one with its own page here.
Ingredients that raise the same concerns.
Where this came from
Truva summarises published guidance from bodies including ACOG, the FDA, the EU SCCS and the Cosmetic Ingredient Review. It has no access to your medical history and it is not a substitute for your doctor, dermatologist or midwife. These assessments have not been reviewed by a clinician, and nothing here is a diagnosis or a prescription. If you are pregnant, breastfeeding or being treated for PCOS, take the ingredient list to the person looking after you.
Assessment last pulled from the ingredient database on .
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A label has thirty of them. Truva reads the whole list at once and answers for the profile you set: pregnancy, breastfeeding, postpartum, trying to conceive, PCOS, or general use.
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