Certifications
Free From
Highlights
Vegan
Cruelty-free
Made in USA
No synthetic fragrance
Recyclable packaging
Recycled materials
For Scalp health
Overnight treatment
Heat protection
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Best Non-Toxic Hair Serums
We vetted hair serums against the Welpr Standard and here are our top picks.
Cofounder & Product Curator
Medical Reviewer, PhD
Here's what we look for:
- Simple formulations using fully natural or safe synthetic ingredients
- No parabens, PEGs, phthalates, harsh sulfates, BHA/BHT, artificial dyes, formaldehyde or formaldehyde releasers, or undisclosed synthetic fragrance (unless certified safe)
- Minimal, necessary preservatives only
- Trusted third-party certifications when available
- Transparent sourcing, ingredients, and manufacturing practices
Best Non-Toxic Hair Serums
On Welpr, terms like "non-toxic," "safer," "cleaner," "healthier," and "vetted" are editorial labels based on our own standard for product assessment. They are not guarantees, certifications, or medical claims. Learn more.
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The 80/20 guide to going non-toxic the easy way.
Certifications
Free From
Highlights
Vegan
Cruelty-free
Pregnancy safe
Breastfeeding safe
Recyclable packaging
For Scalp health
Leave-in
Heat protection
Certifications
Free From
Highlights
Vegan
Cruelty-free
Pregnancy safe
Breastfeeding safe
No synthetic fragrance
For Scalp health
Pre-shampoo treatment
Heat protection
Certifications
Free From
Highlights
Vegan
Made in EU
Recyclable packaging
For Damage repair
Leave-in
How to Swap to Non-Toxic hair serums:
Here's how to swap to non-toxic hair serums:
What to know about hair serum
Hair serums are leave-in products that stay on your hair and scalp for hours or even all day. Because they sit on skin and are applied close to your face, the formulation matters more than with rinse-off hair products.
- Serums often contain synthetic fragrances, silicones, and preservatives that can build up with daily use.
- Welpr focuses on clean formulations, fragrance transparency, and the absence of endocrine disruptors like parabens and phthalates.
Review what you already use
Check the serum you currently use by scanning it with the Welpr Personal Care and Cosmetic Scanner. It will flag any concerning ingredients so you can see how your product stacks up.
- Look at the ingredient list for the word "fragrance" or "parfum"—these can hide undisclosed synthetic ingredients.
- If you use more than one leave-in hair product, scan the one you apply most often or closest to your scalp first.
Use your current serum more carefully
If you're not ready to switch yet, small changes in how you apply your serum can reduce what your skin absorbs. This is especially helpful if your serum contains synthetic fragrance or harsh preservatives.
- Apply serum to the mid-lengths and ends of your hair rather than directly on your scalp.
- Use a smaller amount than you normally would—a little often goes further than the bottle suggests.
Choose a cleaner hair serum
Look for serums with simple, functional ingredients like plant-based oils and natural extracts. Fragrance-free options are best, but if scented, the fragrance should come from essential oils or plant extracts rather than synthetic sources.
- Certifications like EWG VERIFIED™ or MADE SAFE® are a good sign, but Welpr still reviews every formula individually before approving it.
- Click the button above to shop Welpr Approved hair serum.
Camille May
Cofounder & Product Curator
Camille May is the co-creator of Welpr and a guide for clean living. After selling her last company in the health food space, she went non-toxic while working to heal an autoimmune condition....
Olushola M. Awoyemi
Medical Reviewer, PhD
Olushola M. Awoyemi (aka Shola) is a board-certified toxicologist and a research scientist with a PhD in Environmental Toxicology. Shola's long-term ambition is to be recognized as a world-renowned expert in toxicology,...