Tetrachloromethane (TCM)

TCM, Tetraklormetan

Tetrachloromethane is also called carbon tetrachloride. It belongs to the group volatile organic compounds (VOC) and is a colourless, volatile liquid with a sweet odour. It is non-combustible.¹

Uses

Tetrachloromethane is an effective solvent within the chemical industry and is used to clean machinery and electrical equipment. It can also be used in the production of chemical products.² In Sweden it is prohibited to market tetrachloromethane to the general public in concentrations exceeding 0.1 mass percent and to use the substance in ways resulting in exposure.³

Sources and transportation pathways

Tetrachloromethane can be emitted to the environment by industrial use and its waste streams. The chemical industry is the largest emission source among the large point sources in Europe.⁴ The substance evaporates quickly to air where it degrades slowly.⁵

Effects on environment and health

Tetrachloromethane is not classified as acutely toxic but it has high chronic toxicity. It is not readily degradable and is biomagnified in nature. It is an endocrine disruptor and can cause long-term damages to organs and the nervous system.^{6 7} As a VOC, tetrachloromethane can be involved in the formation of ground-level ozone. Ground-level ozone may damage vegetation and during episodes of elevated VOC levels, it may cause irritation of the respiratory tract in humans. Furthermore, the substance is harmful to the ozone layer and to aquatic organisms. It is a greenhouse gas that contributes to the increased greenhouse gas effect^{8 9}. The increased greenhouse gas effect results in an increase of the average temperature on earth, which for example leads to climate change and rising of the sea level.^{10 11}

Inhalation, digestion and severe skin exposure to tetrachloromethane may cause poisoning. Severe exposure may affect the heart and exposure to liquid or gas streams can cause cold-burns.¹²

International agreements and regulations

Tetrachloromethane is regulated by the UN Montreal Protocol and the EU Water Framework Directive (2000/60/EC). The presence of tetrachloromethane in products is regulated by the EU regulation on cosmetic products (EC 1223/2009). The UN Protocol on PRTRs and the EU E-PRTR regulation regulate how data on tetrachloromethane emissions is made available.

As a VOC, tetrachloromethane is indirectly regulated by the UN Convention on Long-Range Transboundary Air Pollution (CLRTAP) and the UN Framework Convention on Climate Change (UNFCCC), as well as by the EU National Emissions Ceilings Directive (2001/81/EC) and the EU Industrial Emissions Directive (2010/75/EU).

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¹ https://rib.msb.se/Portal/template/pages/Kemi/Substance.aspx?id=2668&q=56-23-5&p=1
² https://toxnet.nlm.nih.gov
³ https://www.kemi.se/global/lagar-och-regler/kifs/kifs-20082/k08_2_grund.pdf?_t_id=1B2M2Y8AsgTpgAmY7PhCfg%3d%3d&_t_q=tetrakloretan&_t_tags=language%3asv%2csiteid%3a007c9c4c-b88f-48f7-bbdc-5e78eb262090&_t_ip=195.67.7.30&_t_hit.id=KemI_Web_Models_Media_SiteMediaData/_c73fca9d-0091-41f1-a10b-29828c40a5fc&_t_hit.pos=1
⁴ http://prtr.ec.europa.eu/#/pollutantreleases
⁵ https://toxnet.nlm.nih.gov
⁶ https://rib.msb.se/Portal/template/pages/Kemi/Substance.aspx?id=2668&q=56-23-5&p=1
⁷ https://www.kemi.se/prio-start/sok-i-prio
⁸ http://www.ghgprotocol.org/sites/default/files/ghgp/Global-Warming-Potential-Values%20%28Feb%2016%202016%29_1.pdf
⁹ http://www.naturvardsverket.se/Sa-mar-miljon/Klimat-och-luft/Klimat/Darfor-blir-det-varmare/Andra-vaxthusgaser/
¹⁰ http://www.ipcc.ch/pdf/assessment-report/ar5/syr/AR5_SYR_FINAL_SPM.pdf
¹¹ http://www.smhi.se/kunskapsbanken/klimat/vaxthuseffekten-1.3844
¹² https://rib.msb.se/Portal/template/pages/Kemi/Substance.aspx?id=2668&q=56-23-5&p=1