Minimising nitrosamine formation
Nitrosamines are formed when a secondary amine and nitrite or other nitrosating agent reacts to form nitrosamines. There is evidence from laboratory studies, including studies in animals, that nitrosamines have the potential to cause cancer in various tissues of the body.
Where possible, don’t use metalworking fluids that contain secondary amines. Talk to your supplier.
To remove nitrite or nitrosating agents, check:
- with your suppliers that your fluids do not contain sodium nitrite
- that your water supply, biocides, corrosion inhibitors, cleaners and other products, are not high in nitrites, and
- that the airborne sources of oxides of nitrogen, such as welding and combustion engine fume, are minimized, where metalworking fluids are used.
Controlling polycyclic aromatics (PCAs)
There is evidence from animal studies and epidemiological investigations of various exposed populations that polycyclic aromatic compounds (PCAs) have the potential to cause cancer in various tissues of the body.
PCAs are found everywhere, including crude oil, but nowadays, oils used in the engineering industry in the UK are highly refined. This means they will not contain significant quantities of PCAs.
There is the potential for some PCAs to be formed when metalworking fluids containing mineral oil are used for long periods at high temperatures. Fluid should be delivered to the metalworking operation to provide adequate cooling and prevent overheating. Fluids should be changed in line with suppliers’ recommendations.