The hair relaxer lawsuit: the science and the litigation status

In October 2022, the National Institutes of Health published results from the Sister Study, a long-running epidemiological investigation following 33,497 women for approximately 11 years to study breast cancer risk factors. The findings on hair relaxers and uterine cancer were unexpected and clear. Women who used chemical hair straightening products more than four times per year had 2.55 times the risk of developing uterine cancer compared to women who didn't use them. The increase in lifetime uterine cancer risk by age 70 was substantial: from 1.64% baseline to 4.05% for frequent users.

The Sister Study findings sparked litigation almost immediately. By April 2026, more than 11,000 women had filed lawsuits in federal court alleging that chemical hair relaxers caused uterine cancer, ovarian cancer, endometrial cancer, breast cancer, or uterine fibroids. The cases are consolidated in MDL 3060 in the U.S. District Court for the Northern District of Illinois under Judge Mary M. Rowland.

The defendants are major cosmetic manufacturers including L'Oréal, Revlon, Strength of Nature, SoftSheen-Carson, Dermoviva, Wella, John Paul Mitchell Systems, and approximately a dozen other companies. The named products include widely sold brands: Dark & Lovely, Optimum, Just for Me, and many others marketed primarily to Black women, who have used chemical relaxers in significantly higher proportions than other demographics.

The litigation is still in pretrial discovery as of mid-2026. Judge Rowland has set bellwether case selection for early 2026, with the first trials expected in mid-2027. Science Day was held January 8, 2026, where both sides presented their scientific evidence to the court. This is what the lawsuits allege, what the science actually shows, who qualifies, and where the litigation stands now.

The chemistry and the cancer connection

Chemical hair relaxers work by breaking the disulfide bonds in hair's keratin protein, allowing curly or coiled hair to be reshaped and straightened. The chemicals that accomplish this are powerful, and most contain ingredients identified as endocrine disruptors or carcinogens.

The chemicals of concern in the litigation:

Formaldehyde and formaldehyde-releasing agents. The International Agency for Research on Cancer (IARC) classifies formaldehyde as a Group 1 carcinogen. Many hair relaxers contain formaldehyde directly or contain chemicals that release formaldehyde when activated by heat or chemical reaction during application.

Phthalates. A class of chemicals used as plasticizers and fragrance carriers. Multiple phthalates are classified as endocrine disruptors and have been associated with hormonal cancers including uterine and ovarian cancer. They cross from skin to bloodstream readily.

Parabens. Preservatives commonly used in cosmetics. Several parabens are weak estrogenic compounds, meaning they can bind to estrogen receptors and mimic estrogen's biological effects. Long-term exposure has been associated with hormone-driven cancers.

Bisphenol A (BPA). An industrial chemical with estrogenic activity, present in some hair relaxer formulations as either a deliberate ingredient or a contamination byproduct.

Sodium hydroxide or guanidine carbonate. The actual relaxing agents that break the disulfide bonds. These are highly caustic chemicals that can damage skin and scalp during application, creating pathways for the other chemicals in the product to be absorbed systemically.

The proposed biological mechanism connecting hair relaxer use to cancer: repeated exposure to endocrine-disrupting chemicals through skin (especially when the scalp is irritated or burned from the relaxing process) introduces estrogenic compounds into the bloodstream over years or decades. Chronic exposure to elevated estrogenic stimulation drives proliferation of hormone-sensitive tissues, increasing the risk of cancer in the uterus, ovaries, and breast.

The Sister Study findings on uterine cancer were the strongest signal. The study controlled for known uterine cancer risk factors (obesity, age at menopause, hormone replacement therapy use, family history) and still found the 2.55x relative risk for frequent users. Subsequent studies have generally confirmed the signal, though with varying effect sizes.

The legal theory

The lawsuits allege three primary theories.

Failure to warn. The cosmetic manufacturers had access to scientific literature suggesting endocrine-disrupting potential of their ingredients for decades. The 2022 Sister Study made the cancer connection explicit, but earlier research had raised concerns about the chemicals individually and about hair relaxer ingredients collectively. Manufacturers continued marketing the products without warning about the cancer risks.

Defective design. Alternative formulations of hair relaxers exist that don't include endocrine-disrupting chemicals. Manufacturers chose to continue using formulations with these chemicals despite the availability of safer alternatives.

Marketing targeting. A significant component of some complaints addresses the targeted marketing of hair relaxers to Black women and girls, including children. The disproportionate use of these products in Black communities, combined with the disproportionate rates of uterine cancer in Black women, has become part of the litigation's framing about marketing practices and disclosure.

The defendants' primary defenses:

Causation. Despite the Sister Study and follow-on research, defendants argue that connecting any specific plaintiff's cancer to hair relaxer use requires proof of dose-response and specific causation that the epidemiological data doesn't reliably support. They argue confounding factors (genetic risk, other environmental exposures, lifestyle factors) may explain the association.

No defective product. Defendants argue their products complied with FDA cosmetic regulations and met industry standards at the time of sale. Cosmetics are regulated less stringently than drugs or medical devices, which complicates the defective product analysis.

Statute of limitations. Hair relaxer use often spans decades. Many cancer diagnoses occurred years before the Sister Study made the connection public. Defendants argue some claims are time-barred regardless of the discovery rule.

Where the litigation stands

The procedural posture as of mid-2026 is active discovery with bellwether trial selection underway.

Pending cases. Approximately 11,371 active cases in MDL 3060 as of April 2026, with the total filed (including closed cases) at 15,504. New filings continue at a steady pace.

Science Day. Judge Rowland held Science Day on January 8, 2026. Both sides presented expert testimony to educate the court on the scientific evidence connecting hair relaxer chemicals to uterine, ovarian, and endometrial cancer. The Science Day session helps Judge Rowland evaluate the strength of the science before bellwether trials proceed.

Bellwether selection. From a pool of 32 cases, three bellwether cases will be selected by April 1, 2026. Plaintiffs choose one bellwether by April 6, defendants choose one by April 10, with Judge Rowland selecting the third. The bellwether cases will go through accelerated fact discovery and prepare for trial.

Discovery deadlines. Additional bellwether fact discovery closes June 10, 2026. Daubert motions and summary judgment motions are due November 16, 2026. Trial schedules for the bellwether cases are expected to begin in mid-2027.

Settlement infrastructure. Special Master Ellen K. Reisman continues overseeing settlement discussions. Revlon, which filed for Chapter 11 bankruptcy in 2022, set aside $44 million for hair relaxer claims as part of its bankruptcy proceedings. Other defendants haven't made comparable public reservations but are negotiating in parallel with the litigation track.

Discovery disputes. Defendants have offered written stipulations rather than live deposition testimony for corporate witnesses on marketing, warnings, and labeling decisions. Plaintiffs have pushed back, seeking live testimony. The disputes are being resolved through Judge Rowland's case management orders. Revlon's attempt to subpoena the NIH for the Sister Study underlying data was denied in July 2025.

Industry research. Plaintiff discovery has shown limited corporate research into long-term health effects of hair relaxer ingredients. The absence of robust pre-market safety studies on long-term carcinogenic potential is part of the plaintiffs' liability case.

Who qualifies

Qualification criteria for the MDL have stabilized as the litigation has developed.

Documented hair relaxer use. Most firms require at least one year of regular use, often more, with use occurring before the qualifying diagnosis. Documentation can include:

• Product purchase records (receipts, photos of products)
• Photos of packaging from products used
• Salon records if relaxers were applied professionally
• Witness statements from family members or stylists

Diagnosed qualifying condition. The MDL has focused bellwether trials on:

• Uterine cancer (the strongest scientific evidence, 2.55x risk in the Sister Study)
• Ovarian cancer (growing body of supporting research)
• Endometrial cancer (closely related to uterine cancer)
• Uterine fibroids (lower threshold than cancer, included in some firms' intake)
• Breast cancer (later addition, more contested causation)

Temporal connection. The diagnosis must have followed hair relaxer use, with sufficient cumulative exposure to plausibly support causation. Most firms apply a baseline of regular use over multiple years before diagnosis.

No pre-existing condition that explains the diagnosis. Cases with strong alternative explanations (family history of the specific cancer, known genetic risk factors like BRCA mutations) may face more difficult causation challenges but aren't categorically disqualified.

Statute of limitations compliance. Generally 2 to 3 years from diagnosis or from discovery of the connection between hair relaxer use and the diagnosis, varying by state. The 2022 Sister Study publication often serves as the discovery trigger for plaintiffs who used hair relaxers for decades without awareness of the cancer connection. State-specific analysis remains critical.

What cases are worth

No settlement framework has emerged, and individual case values cannot be reliably predicted before bellwether outcomes. Plaintiff attorneys generally project individual settlement values in ranges between $50,000 and $750,000 depending on the strength of the case and the type and severity of the diagnosis.

The factors most affecting case value:

Type of cancer. Uterine cancer cases have the strongest causation evidence and tend to support the highest projected values. Ovarian and endometrial cancer cases are valued similarly but with somewhat less developed causation support. Breast cancer cases are valued lower because the causation evidence is more contested. Uterine fibroid cases have lower projected values because the injury is less severe.

Stage and severity. Advanced-stage cancers, cancers requiring hysterectomy, cancers with metastatic spread, and cases with permanent reproductive consequences carry higher values than early-stage cancers with full recovery.

Duration of use. Decades of consistent hair relaxer use supports both stronger causation and higher damages. Cases with shorter use history face more challenging causation arguments.

Age at diagnosis. Younger plaintiffs with longer expected impact and lost earning capacity tend to carry higher economic damage components.

Medical and economic damages. Documented treatment costs, lost wages, future medical care, and pain and suffering all contribute to compensatory damages.

The bellwether trials, when they occur in 2027, will be the first meaningful data points on actual case values. Until then, the projected ranges are estimates from attorneys experienced in similar pharmaceutical and product mass tort cases.

What to do if you may qualify

The procedural path to filing a hair relaxer claim is established.

Gather documentation of hair relaxer use. Many users of these products don't have purchase receipts going back decades. Photos of products, packaging, or applications can help. Statements from family members, hairstylists, or salon records can establish use. The standard isn't perfect documentation but reasonable evidence of regular use over time.

Gather medical records. Diagnosis records, pathology reports, treatment records, family medical history, and any prior gynecological history. The records will be needed for case evaluation and for the medical causation analysis.

Confirm statute of limitations. Most states use the discovery rule for these cases, with the 2022 Sister Study publication often serving as the discovery trigger. This generally keeps the filing window open for plaintiffs who used hair relaxers and received diagnoses before October 2022, as long as they file within 2 to 3 years of becoming aware of the connection. State-specific analysis is critical.

Consult an MDL attorney. Standard contingency fees (typically 33% to 40% plus expenses). Ask about experience with MDL 3060, current case acceptance criteria, and whether the firm handles your specific qualifying condition.

Decide on filing venue. Cases can be filed directly in MDL 3060 in the Northern District of Illinois under Judge Rowland's direct filing order, or filed in state court and transferred to the MDL for coordinated pretrial proceedings.

Expect a multi-year timeline. Bellwether trials are scheduled for mid-2027 at earliest. Settlement negotiations may accelerate after the first verdicts. Resolution of the broader MDL is likely to extend into 2028 and beyond. The decision to file should account for the realistic timeline, not the marketing language of "fast settlement" that some firms use.

The hair relaxer litigation is one of the larger active product mass torts and rests on stronger initial scientific evidence than many comparable cases. The Sister Study's 2.55x uterine cancer risk for frequent users is a substantial finding, and the demographic context (disproportionate use in Black communities, disproportionate uterine cancer rates in Black women) has elevated public awareness and legal pressure on the manufacturers. The litigation is moving methodically through bellwether selection and discovery, and the procedural path to filing remains open for plaintiffs with qualifying conditions and timely claims.