Occupational exposure to volatile nitrosamines in foundries using the "Ashland" core-making process

Area of Science:

• Occupational Health
• Industrial Hygiene
• Chemical Carcinogenesis

Background:

• Volatile nitrosamines are known carcinogens.
• Foundries utilize processes that may generate nitrosamines.
• Occupational exposure to these compounds is a significant health concern.

Purpose of the Study:

• To assess occupational exposure to carcinogenic volatile nitrosamines in eight foundries using the Ashland process.
• To identify specific nitrosamines and their concentrations during core production and molding operations.
• To evaluate the effectiveness of current sampling and analytical methods.

Main Methods:

• Survey of eight foundries employing the Ashland core production process.
• Collection of personal and area air samples using artifact-free cartridges.
• Analysis of samples via gas chromatography with Hall detector and thermal energy analyzer (TEA).

Main Results:

• Core-making workshops exhibited the highest concentrations of N-nitrosodimethylamine (NDMA) and N-nitrosoethylmethylamine (NEMA).
• NDMA levels did not exceed 0.35 microgram/m3, with arithmetic means ranging from 0.02 to 0.23 microgram/m3.
• NEMA was identified as an industrial contaminant for the first time in foundries, at concentrations lower than NDMA. Molding/casting/shake-out areas showed lower nitrosamine levels.

Conclusions:

• The Ashland process in foundries leads to occupational exposure to carcinogenic nitrosamines, primarily during core-making.
• N-nitrosodimethylamine (NDMA) and N-nitrosoethylmethylamine (NEMA) are key contaminants, likely originating from dimethylethylamine (DMEA).
• Industries using tertiary or secondary amines require monitoring for potential nitrosamine contamination to mitigate health risks.