Identification and classification
Trichloroethylene, abbreviated TCE, is neither tetrachloroethylene nor dichloromethane. IARC classifies it as carcinogenic to humans, Group 1, in its evaluation of chlorinated solvents. Some older sources list previous categories. Preventive assessment must use current information and check requirements applying to the specific use, without assuming that a historically used product remains acceptable in every process.
Effects beyond cancer
NIOSH identifies irritation, dizziness, drowsiness, visual disturbances and effects on various organs. ILO/WHO lists effects on the central nervous system, liver, kidneys and immune system. High exposure can cause loss of consciousness. These effects also require control of acute incidents and skin contact; attention to chronic risk must not obscure a leak or hazardous open operation.
Where exposure may remain
Cleaning, opening equipment, waste handling and maintenance can involve exposures different from the main cycle. Leak points and accumulation areas are identified. Out-of-service equipment retaining solvent must also be reviewed. Sampling needs to represent relevant people and operations, not merely a period of stable, contained operation.
Substitute with sound criteria
Substitution of the agent or process requires comparison of risks and technical performance. Switching to another chlorinated solvent does not automatically demonstrate sufficient improvement. Where an authorised use continues, containment and exposure reduction measures must be justified and verified alongside the specific legal requirements applying to the site.
Control interventions and waste
Procedures must define isolation, emptying and opening conditions, as well as compatible containers and materials. Protection is selected specifically for the task. Possible decomposition products and work involving heat are reviewed. Waste management avoids transferring risk to cleaning staff or another company and retains identification of contents throughout the operation.
Review example
In a hypothetical example, a company removes trichloroethylene from routine cleaning but finds residues in old equipment. The plan includes removal and decontamination by trained personnel before substitution is declared complete. Verification distinguishes stopping purchases from eliminating all exposures. Health surveillance uses historical information where appropriate without replacing technical controls.
