Sodium hydroxide (solution)

Made by the chlor‑alkali process; found in drain/oven cleaners, degreasers, and industrial processes (paper, textiles, petroleum, water treatment, some food processing) [1][4].

Handling concentrated solutions or mists at work; splashes when mixing or opening drains; home use of drain/oven cleaners; rare exposure from very high‑pH water or spills [1][2][3].

Causes fast chemical burns; severe eye injury or blindness; swallowing can burn the mouth, esophagus, and stomach; inhaling mists irritates or swells airways. Not known to cause cancer or build up in the body; main risk is corrosivity [1][2][3][4].

Workers in cleaning, pulp/paper, chemical manufacturing, food processing, and plumbing; janitors; children in homes with drain openers; people with asthma or chronic lung disease [1][2].

Store locked and labeled; use gloves and eye/face protection; add lye to water, never water to lye; don’t mix with acids or aluminum; ventilate; choose milder products when possible; if contact occurs, rinse with water for at least 15 minutes and seek medical care [1][2][4].