Metalworking fluid--the toxicity of a complex mixture

Area of Science:

• Occupational Health
• Toxicology
• Environmental Health

Background:

• Metalworking fluids (MWFs) are complex mixtures used for cooling and lubrication.
• Assessing the health risks of MWFs is challenging due to diverse chemicals and contaminants.
• Adverse pulmonary effects are reported in workers exposed to MWF aerosols.

Purpose of the Study:

• To review methodologies for assessing MWF toxicity.
• To identify the primary causes of adverse pulmonary effects from MWF exposure.
• To highlight the role of microbial degradation products in MWF-related lung issues.

Main Methods:

• Review of toxicological studies on MWF components and contaminants.
• Analysis of research investigating pulmonary effects of MWF aerosols.
• Evaluation of evidence linking microbial changes to toxicity.

Main Results:

• Chemical composition alone does not fully explain MWF toxicity.
• Microbial changes in MWF during use are strongly implicated in adverse effects.
• Bacterial endotoxin is identified as a significant contributor to pulmonary toxicity.

Conclusions:

• The toxicity of modern MWFs is complex and influenced by microbial activity.
• Bacterial endotoxins in MWFs are a major cause of occupational lung disease.
• Further research and risk assessment should focus on microbial contaminants and their byproducts.