• Chlorine Online Home
• All about chlorine
• All about the European chlorine industry
• Euro Chlor Regulatory Affairs
• Energy - Climate
• Euro Chlor Science Programme
  • Science communications
  • Focus on Chlorine Science
  • Key Science Information Sheets
  • Science dossiers
  • RCEI: Reactive Chlorine Emission Inventory
  • Natural chemistry of chlorine in the environment
  • Risk & hazard – How they differ
  • Marine risk assessments
    • 1,2-dichloroethane
    • 1,1,1-trichloroethane
    • 1,1,2-Trichloroethane
    • Vinyl chloride
    • Tetrachloroethylene
    • Monochlorobenzene
    • Trichloroethylene
    • 1,2-dichlorobenzene
    • Chloroform
    • 1,4-dichlorobenzene
    • Carbon tetrachloride
    • Mercury
    • Dichloromethane
    • Monochlorophenols (2-, 3- and 4-)
    • Hexachlorobenzene
    • PCBs, DDT and dioxin
    • Hexachlorobutadiene
    • Pentachlorophenol
    • 1,2,4-Trichlorobenzene
    • 1,1-dichloroethene
  • High Production Volume chemicals
  • The Biocidal Products Directive
• REACH update - Consortia
• Euro Chlor Technical Corner
• News room
• All about Euro Chlor
• ECSA - The European Chlorinated Solvent Association - new
• The Chlorinated Paraffins Sector Group
• Library
• Useful links
• Contact us
• How to find us
• Access keys

Tetrachloroethylene

Report

To read the report please click here.

This marine risk assessment was also published in a peer-reviewed journal: De Rooij, C. et al., 1998. Euro Chlor risk assessment for the marine environment Osparcom region: North Sea – Tetrachloroethylene. Environmental Monitoring and Assessment, Vol. 53, (3), 489-508.

Summary

Current usage of tetrachloroethylene (also known as perchloroethylene) does not represent a risk to the marine environment in the North Sea. This conclusion is based on 39 aquatic toxicity studies, plus 1991-95 North Sea analytical monitoring results.

Applications of tetrachloroethylene

In 1994, 164,000 tonnes of tetrachloroethylene was produced by six companies in the EU. Sales totalled 78,000 tonnes and exports, 20,000 tonnes. The remainder was used by the chemical industry as an intermediate. EU production and use of the product fell from 340,800 tonnes in 1986 to 164,000 tonnes in 1994.

The main uses of tetrachloroethylene are:

• Dry cleaning - It is the main substitute for the solvents, 1,1,1-trichloroethane and R113, which are controlled under the Montreal Protocol. Use of more efficient dry-cleaning machines and greater recycling has reduced consumption of tetrachloroethylene. Some 60,000 tonnes were used in 1991 by about 60,000 dry-cleaning shops.
• Metal cleaning & degreasing - Whilst trichloroethylene is the main substitute for 1,1,1-trichloroethane in this application, there has also been a rise in tetrachloroethylene use.
• Chemical synthesis - Before the Montreal Protocol phase-out, tetrachloroethylene was used as feedstock for production of solvents and refrigerants such as R113, R114 and R115. It is now used as a raw material for production of the CFC substitutes, HFCs and HCFCs, and its use for chemical synthesis continues to decline.
• Others - Tetrachloroethylene is used in small quantities to make paint removers, printing inks, adhesives, special cleaning fluids, dye carriers and silicone lubricants.

Tetrachloroethylene is manufactured by chlorination or oxychlorination of raw materials such as propylene, dichloroethane, chloropropenes and chloropropanes. It is mainly produced jointly with trichloroethylene by the so-called "TRI/PER" process. This is based on chlorination or oxychlorination of the light fractions of residues from vinyl chloride monomer (VCM) manufacture.

Tetrachloroethylene can also be produced jointly with carbon tetrachloride in the "CTC/PER" process; this has been modified substantially to reduce the production of carbon tetrachloride.

Evaluation of environmental risk

For tetrachloroethylene, the evaluation of toxicity was based on eight sets of data for algae, 13 for invertebrates and 18 for fish in both marine and freshwater media. These were assessed using the environmental quality criteria recommended by the European authorities.

Both acute and chronic toxicity studies were taken into account, and the appropriate assessment factors were used to define a final Predicted No-Effect Concentration (PNEC) value of 51 µg/litre.

Monitoring measurements were taken in Germany (Elbe and Weser estuaries, coastal water), the Netherlands (Rhine estuary, Maas), the German/Dutch border (Rhine), the Belgian/Dutch border (Maas, Meuse), Schelde estuary, the UK (Mersey & other river estuaries) and France (Seine estuary).

The most recent data (1991-95) support a typical PEC of 0.2 µg tetrachloroethylene/l water and a worst case PEC of 2.5 µg/l water. Data on persistence of tetrachloroethylene indicate a half-life in water of a few hours or days, and negligible bioaccumulation in aquatic organisms. It is not a substance which should be considered as being persistent, toxic and liable to bioaccumulate (PTB) in the environment.

Conclusion

When the environmental concentration of tetrachloroethylene in rivers and coastal waters/estuaries is compared with the predicted no-effect level to give the PEC/PNEC ratio, there is a safety margin of 20-250 between actual exposure and the level at which no effect on the environment would be expected. This calculation takes no account of any further dilution within the sea, which would increase these safety margins.

Current use of tetrachloroethylene does not, therefore, represent a risk to the marine environment.

This evaluation was done as a parallel exercise with the continuing European Risk Assessment, the scope of which is broader and covers all compartments.

North Sea monitoring data on tetrachloroethylene