Daijiworld Media Network - Mumbai

Mumbai, Jan 1: A growing number of case reports and studies indicate that keratin hair straightening products containing glyoxylic acid, marketed as “formaldehyde-free,” are causing sudden kidney damage, posing a new public health concern. Young women, particularly those visiting salons for hair-straightening treatments, appear to be the most affected.

Doctors report that symptoms typically appear within hours to three days after treatment, including nausea, vomiting, abdominal discomfort, and general malaise. Laboratory tests reveal elevated creatinine and urea, hyperkalemia, and acidosis. Kidney biopsies have consistently shown oxalate crystal deposits, acute tubular injury, and occasional interstitial nephritis. Most patients recover with supportive care, while only a few require dialysis.

A 25-year-old woman, previously healthy, developed acute kidney injury (AKI) after receiving a glyoxylic-acid keratin treatment. She presented with severe nausea, vomiting, elevated creatinine (3.2 mg/dL), blood urea nitrogen (45 mg/dL), high potassium levels (6.2 mmol/L), and metabolic acidosis (pH 7.25). Immediate hospital care, including fluids and electrolyte management, led to full recovery. Medical teams confirmed that the hair treatment triggered the kidney damage.

Formaldehyde-free hair straighteners use glyoxylic acid under heat to restructure hair bonds. When absorbed through the scalp, the compound converts to oxalate, forming calcium oxalate crystals that block kidney tubules, resulting in “oxalate nephropathy.” Studies and kidney biopsies confirm the direct link between glyoxylic acid exposure and acute tubular injury.

Since 2019, multiple reports from different countries have documented similar AKI cases in women using glyoxylic-acid products. A case series in Israel highlighted 13 women who developed kidney failure following salon treatments, with oxalate crystals detected in urine. Most recovered with intravenous fluids and vitamin therapy, including thiamine and pyridoxine, which may help redirect glyoxylate metabolism.

Many consumers choose formaldehyde-free hair straighteners to avoid lung and scalp risks, unaware that glyoxylic acid can still form toxic compounds when heated. Regulatory authorities in Europe have issued warnings through cosmetovigilance systems about the risk of acute kidney injury.

• Salons must review product safety information and avoid glyoxylic-acid formulations.
• Avoid scalp contact and adhere to recommended exposure times during treatments.
• Clients experiencing nausea, vomiting, or urine changes after treatments should consult doctors promptly.
• Health professionals should consider recent hair treatments as a possible cause of sudden AKI in healthy young women.

Experts emphasize the urgent need for stricter oversight, clearer labeling of active ingredients, and research into population-specific risks. Further studies are needed to determine whether thiamine and pyridoxine supplementation can prevent kidney damage in exposed individuals.

The rise of glyoxylic-acid-related AKI underscores the hidden dangers behind “formaldehyde-free” cosmetic products and the importance of consumer awareness.