Basic Orange 31

Basic Orange 31 and pregnancy

Not Recommended

• Absorbed into the body

Basic Orange 31 is a synthetic azo dye used primarily in hair coloring products. Hair dyes have been a topic of discussion in pregnancy safety due to concerns about chemical absorption through the scalp, particularly when products are left on for extended periods. While specific data on Basic Orange 31 in pregnancy is limited, ACOG's guidance on hair dyes during pregnancy notes that most evidence suggests occasional use of hair dyes after the first trimester appears relatively safe, though they recommend waiting until after the first trimester as a precautionary measure. The concern with synthetic dyes involves potential systemic absorption and theoretical fetal exposure, particularly during the critical first trimester when organ development occurs. Many obstetricians suggest that pregnant women who wish to color their hair consider waiting until after the first trimester, ensuring good ventilation, minimizing scalp contact, and reducing frequency of application. Some pregnant women choose to avoid synthetic dyes altogether, opting for semi-permanent or plant-based alternatives, or delaying hair coloring until after pregnancy.

Basic Orange 31 and breastfeeding

Safe to Use

The concern with synthetic hair dyes during pregnancy relates primarily to potential fetal exposure during critical developmental periods. During breastfeeding, the theoretical risks are considerably lower, as these colorants are applied externally and any minimal absorption would be further diluted before potentially reaching breast milk. While specific data on Basic Orange 31 in breast milk is not available, the general consensus among dermatologists is that external use of hair dyes during breastfeeding is considered low-risk. The molecular structure and application method make significant transfer to breast milk unlikely. For breastfeeding mothers who choose to use hair coloring products, standard precautions include ensuring good ventilation, following manufacturer instructions, and avoiding prolonged or excessive scalp contact. Most dermatologists consider hair dyeing compatible with breastfeeding.

Basic Orange 31 and postpartum

Safe to Use

• Common allergen
• Irritant

For postpartum women not breastfeeding, the primary considerations with Basic Orange 31 are the same as for the general population: potential for allergic reactions and skin sensitivity. The pregnancy-specific concerns no longer apply. Some women may experience increased skin sensitivity in the postpartum period due to hormonal changes. A patch test before using products containing synthetic dyes is advisable, particularly if this is a new product or if postpartum skin has been more reactive than usual.

Basic Orange 31 and trying to conceive

Caution Advised

• Absorbed into the body

During the trying-to-conceive period, many women choose to adopt pregnancy-safe practices even before conception is confirmed. Since it may take several weeks to realize pregnancy has occurred, following pregnancy precautions for hair dyes is a common approach for those actively TTC. While the evidence does not suggest that occasional hair dye use affects fertility or early embryonic development, women who prefer a cautious approach may choose to limit use of synthetic dyes like Basic Orange 31 during their TTC period. Alternative hair coloring methods or waiting to color hair may be preferred by some women during this time.

Basic Orange 31 and PCOS

Safe to Use

Basic Orange 31 is a synthetic colorant that does not interact with hormones or affect androgen levels, insulin sensitivity, or other metabolic aspects of PCOS. It is safe for women with PCOS from a hormonal perspective. The only considerations for women with PCOS are the same as for the general population: potential for allergic reactions or skin sensitivity. Women with PCOS who have sensitive or reactive skin should perform patch tests before using products containing synthetic dyes. This ingredient does not interfere with PCOS management, medications, or hormonal treatments. It can be used in cosmetic products without concerns about affecting PCOS symptoms or hormone balance.

Basic Orange 31 and general use

Safe to Use

• Common allergen
• Irritant

Basic Orange 31 is a synthetic hair dye colorant that serves the functional purpose of providing orange tones to hair coloring products. It is approved for use in cosmetics under current EU regulations with specific concentration limits and required warnings. The primary health consideration for general users is the potential for allergic contact dermatitis. Synthetic dyes, particularly azo dyes, are known sensitizers for some individuals. The EU regulations require that products containing hair dyes display warnings about potential allergic reactions and recommend patch testing before use. Anyone with a history of dye allergies should exercise caution. For most people without dye sensitivities, Basic Orange 31 in properly formulated cosmetic products poses low risk when used according to manufacturer instructions. Ensuring good ventilation during application, following recommended contact times, and performing a patch test before first use or when trying a new product are standard safety practices for hair dye use.

Everything else flagged for the same profiles

• Flagged in pregnancy
• Flagged in trying to conceive

Related ingredients

Ingredients suggested in place of Basic Orange 31, each one with its own page here.

• Henna

Ingredients that raise the same concerns.

• Parfum/FragranceIrritant, Common allergen, Absorbed into the body
• Lavandula Angustifolia OilIrritant, Common allergen, Absorbed into the body
• Melaleuca Alternifolia Leaf OilIrritant, Common allergen, Absorbed into the body
• EugenolIrritant, Common allergen, Absorbed into the body
• Rosmarinus Officinalis Leaf OilIrritant, Common allergen, Absorbed into the body
• DMDM HydantoinIrritant, Common allergen, Absorbed into the body

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 15 September 2026.