The Formulator's Guide to a Truly Clean Eyeliner
By Ryan Cheng, CRO at Nature Coatings
SUMMARY: Eyeliner is applied closer to the eye's mucous membrane than any other cosmetic product, yet most formulations still depend on a petroleum-derived pigment classified as a possible human carcinogen.
Every cosmetic chemist I talk to knows the eyeliner problem. They just don't love talking about it.
The global eyeliner market is projected to reach $3.74 billion by 2035, growing at a 6.4% CAGR driven largely by consumer demand for clean beauty formulations. The natural and organic segment alone is growing at 5.63% annually. Consumers want clean. Brands want clean. The problem is that most of what's on the market isn't. Not where it counts.
Start with the black pigment. Eyeliner is applied directly to the lash line, often to the waterline, millimeters from the eye's mucous membrane. The skin surrounding the eye, the periorbital area, is among the most permeable on the human face. Whatever you put there absorbs more readily than almost anywhere else on the body. A recent study on lead contamination in eyeliners underscores just how much scrutiny this product category deserves. The pigment decision in eyeliner formulation is disproportionately consequential.
The default choice for delivering a deep, true black has been carbon black, a petroleum byproduct manufactured by the incomplete combustion of coal tar and fossil fuel feedstocks. The International Agency for Research on Cancer (IARC) classifies carbon black as a Group 2B possible human carcinogen. NIOSH has flagged concerns about lymphatic cancer among exposed workers due to polycyclic aromatic hydrocarbons (PAHs) present in carbon black. PAHs damage DNA. Some are classified as Group 1 carcinogens. And they are present in the pigment that formulators have been putting next to the eye for decades.
The alternative that most clean brands reach for is black iron oxide. It sounds cleaner. It performs worse. Iron oxide doesn't deliver a true black. It goes gray, ashy, flat. In a product category where consumers expect precision and intensity, that's a dealbreaker.
A third option now exists. BioBlack Beauty is made from FSC-certified recycled wood waste. It is free of PAHs, VOCs, and PFAS. It is non-nano. It is the first and only black pigment for cosmetics certified by the USDA as 100% biobased. In side-by-side evaluations, it matches or exceeds conventional carbon black on jetness, tint strength, and dispersion in both oil and water phases.
But solving the pigment is only part of the formulation challenge. Eyeliner demands precision that mascara and lipstick don't. Liquid liners need consistent flow through a felt tip or brush applicator without clogging or skipping. Pencil liners need controlled deposit and clean edges. Gel liners need to hold their position on the lid without migrating into the crease. Each format imposes different rheological requirements on the pigment dispersion, and the dispersion has to perform without the PFAS-based film formers that conventional waterproof eyeliners rely on.
BioBlack Beauty's particle size distribution and surface chemistry were engineered for exactly this kind of formulation work. It disperses cleanly in both aqueous and anhydrous systems. It doesn't agglomerate in fine-tip applicators. And because it carries no petroleum chemistry, it simplifies the regulatory compliance picture at a moment when sustainability mandates are reaching the materials layer across global markets.
The clean eyeliner market is growing because consumers are asking better questions. Formulators need better answers. Not iron oxide compromises. Not carbon black liabilities. A natural black pigment that performs at the level the category demands, with a toxicology profile that belongs near the eye.
Explore BioBlack Beauty and request a sample by contacting us.