N-nitrosodiethanolamine in antifreeze.

Area of Science:

• Environmental Chemistry
• Toxicology
• Industrial Safety

Background:

• Antifreeze formulations commonly contain triethanolamine derivatives and sodium nitrite for corrosion inhibition.
• N-nitrosodiethanolamine (NDELA) is a known carcinogen with potential environmental and health risks.
• Previous research has not extensively documented NDELA presence in commercial antifreeze products.

Purpose of the Study:

• To quantify N-nitrosodiethanolamine (NDELA) levels in leading French antifreeze brands.
• To investigate the formation of NDELA from mixtures of antifreeze components.
• To assess the role of sodium nitrite in NDELA formation within antifreeze.

Main Methods:

• Gas chromatography-mass spectrometry (GC-MS) was employed for the detection and quantification of NDELA.
• Analysis was performed on multiple commercial antifreeze samples from French markets.
• Laboratory experiments were conducted to study the reaction between triethanolamine derivatives and sodium nitrite.

Main Results:

• NDELA was detected in French antifreeze brands at concentrations ranging from 15 to 5700 mg/L.
• Mixtures of antifreezes, innocuous individually, demonstrated NDELA formation upon combination.
• The interaction between triethanolamine derivatives and sodium nitrite was identified as the primary source of NDELA.

Conclusions:

• The presence of carcinogenic NDELA in commercial antifreeze poses a significant health and environmental concern.
• The formation of NDELA is exacerbated by the combination of specific antifreeze ingredients, particularly sodium nitrite.
• Abandoning sodium nitrite as an anticorrosion additive in antifreeze formulations is strongly recommended to mitigate NDELA risks.