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Monoethanolamine Thioglycolate

  • Reducers
  • CAS 126-97-6
  • IUPAC: 2-aminoethanol; 2-sulfanylacetic acid

Signal word DANGER per SDS when at 10-25% concentration. H318 (serious eye damage Cat 1) — primary driver of DANGER classification. H319 (eye irritation Cat 2A) and H315 (skin irritation Cat 2) also present. H301 (toxic if swallowed). Oral LD50 181 mg/kg (rat). No respiratory sensitizer classification. Characteristic sulfur/thioglycolate odor during use.

Monoethanolamine thioglycolate (MEA thioglycolate) is the iron-reactive active ingredient used in modern iron removers. It is the monoethanolamine salt of thioglycolic acid and functions by chelating ferrous iron (Fe²⁺) from brake dust, rail dust, and fallout particles bonded to painted, glass, or wheel surfaces. The reaction produces a visible purple iron-thioglycolate complex, giving users direct feedback on iron load. MEA thioglycolate is used in place of ammonium thioglycolate in some formulations because it offers comparable reactivity with a slightly different odor profile. The sulfur character (characteristic of all thioglycolate chemistry) is unavoidable at consumer concentrations. ## Regulatory status - Not CA Prop 65 listed - IARC: Not classified as carcinogen - Not an asthmagen or respiratory sensitizer per current SDS data

Health & environment profile

VOC
no
Prop 65 listed
no
Asthmagen
no
EPA Safer Choice
no
Aquatic toxicity
no
Biodegradable
yes
Bioaccumulative
no
Persistent
no
Ozone depleting
no
Microplastic
no
PFAS
no
Env. score
4/5
Purpose: Iron decontamination active — reacts with ferrous iron oxide (brake dust, rail dust) to form a soluble iron-thioglycolate complex, producing the characteristic purple color-change reaction

2 products contain this

Health summaries are editorial — we synthesize from SDSs, peer-reviewed sources, and regulatory listings. Not medical advice.