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Q&A on trichloroethyleneCan I still use TRI and under what conditions is it safe to use?Yes, you can still use TRI safely if you follow ECSA recommendations. These recommendations suggest the use of trichloroethylene in properly maintained equipment, by fully trained personnel operating in accordance with standard guidelines: use of closed systems, recycling loop systems, properly ventilated area. These practices are well known and have been recommended for many years, and in fact are becoming regulated standards in many areas of Europe. Special and detailed recommendations are available on request at ECSA. Since when has the new classification and labelling been applied?This decision was included in Directive 2003/36/EC (25th amendment to the Marketing & Use Directive 76/769/EEC) on 26 May 2003. Member States have since transposed the labelling requirements into national law. What does the label look like? What impact will this change in labelling have?According to the European Dangerous Substances Regulation 67/548/EEC, the label now used on shipments of trichloroethylene looks as follows:
T R: 36/38,45,67,52/53 S: (2-)45-53-61 Carcinogenicity Cat. 2; Mutagenicity Cat. 3 T: Toxic R45: May cause cancer R36/38: Irritating to eyes and skin R67: Vapours may cause drowsiness R52/53: Harmful to aquatic organisms, may cause long term adverse effects in the aquatic environment S2: Keep out of the reach of children S45: In case of accident or if you feel unwell, seek medical advice immediately S53: Avoid exposure - obtain special instructions before use S61: Avoid release to the environment. Refer to special instructions/Safety data sheets Apart from the product packaging requiring this label, you are required to review your working practices to ensure that you meet your local legislative obligations with respect to handling an R45 product. In addition:
If substitution under the VOC Directive is required, what are the alternatives to TRI?Although a range of possible alternative products is available today, experience has shown that substitution of TRI is not easy and even not feasible for a number of specific cases, either for technical or economical reasons. For all cases, substitution of TRI needs a thorough evaluation of all process aspects. For this reason we intend to work with the authorities in order to prevent a blanket implementation of forced substitution, and allow sustainable and continued safe use of TRI. The alternatives you will probably consider first are the chlorinated solvents perchloroethylene (PER) and methylene chloride (MC). They match closest the technical features of TRI, such as non-flammability, high solvency power, a wide range of material compatibility and excellent drying and recycling properties. Beside PER and MC, you have probably also heard about other alternatives such as aqueous (water-based) alkaline systems, flammable solvents (e.g. hydrocarbons or modified alcohol based formulations), supercritical CO2 or hydrofluorocarbons (HFCs), etc. It is impossible to say definitively which technology is best. That depends on your specific application, on what you are cleaning, which materials you want to remove, the cleanliness required, the variability of the parts cleaned, the throughput to be achieved, the cycle times, etc. For example, for the cleaning of parts between two water-based manufacturing steps (e.g. galvanising), aqueous systems may be better, since parts are put into water phase again later and no energy-intensive drying step to remove the water is required. If you need to have very clean and dry surfaces (for coating or surface hardening, for example) and if you have a variety of different metals or blind holes, narrow distances and very fine orifices or a lot of residual oil to clean, hydrocarbons or aqueous systems may not clean and dry well enough. In these cases, chlorinated solvents will offer most often the best solution as they are compatible with most materials, have a high cleaning power, are easy to dry, don't leave residual films and are easy to recycle with high quality by distillation. In addition, chlorinated solvents are today best suited to be used in modern closed systems with minimal losses. Their ecological performance has very much increased and, when used in well-operated metal cleaning systems, they outperform aqueous cleaning as long as drying is required. This has been shown by a Life Cycle Analysis carried out by Ecobilan. PER comes closest to TRI in technical performance and is often the first choice candidate as an alternative to TRI. However, it shows clear inherent technical differences, which need to be taken into consideration. On one side, PER offers a lower volatility and therefore is advantageous to minimise emissions in closed equipment. On the other side, PER has a lower solvency power and is therefore normally used at a higher cleaning temperature to achieve similar performance. This may raise concerns regarding the compatibility with specific metal working fluids and temperature-sensitive parts. Methylene chloride (MC) shows excellent cleaning properties already at low temperatures, favouring the cleaning of temperature sensitive parts. However, its high volatility makes emission control more difficult and requires special equipment. Hydrofluorocarbons (HFC) and hydrofluorocarbon ethers (HFCE) are very expensive and show very limited solvency power. A thorough evaluation of the global warming potential is also required to choose the adequate product. A short overview about the arguments for and against the alternatives in comparison with TRI is given in the table below (n-propyl bromide is not included). It has been proposed for classification as a category 2 reproductive toxin and therefore needs substitution.
Should I invest in alternatives?This labelling change in itself does not require substitution. It is other EU directives that may require you to consider alternatives. The replacement of TRI is in most cases a complicated task, which needs a very thorough investigation of all possible impacts on product quality and linked processes. In order to choose the right cleaning solvent and to get the best solution from a technical, safety, environmental and financial point of view, individual customers' aspects need to be carefully evaluated. A hurried conversion to an alternative without thorough investigations may lead to wrong decisions. ECSA encourages users to contact solvent producers in order to get help in making the right decision. What is the science behind this reclassification?The EU Working Group on Classification, Packaging and Labelling has recommended a change in the current health classification of TRI from cancer Category 3 (Substances which cause concern for man owing to possible carcinogenic effects but in respect of which the available information is not adequate for making a satisfactory assessment. There is some evidence from appropriate animal studies, but this is insufficient to place the substance from Category 3 with risk phrase R40 (Possible risks of irreversible effects) to Category 2 (Substances which should be regarded as if they are carcinogenic to man. There is sufficient evidence to provide a strong presumption that human exposure to a substance may result in the development of cancer, generally on the basis of appropriate long-term animal studies or other relevant information) with risk phrase R45 (May cause cancer) and adding a new Category 3 mutagen (Substances which cause concern for man owing to possible mutagenic effects. There is evidence from appropriate mutagenicity studies, but this is insufficient to place the substance in Category 3 classification. The recommendation is mainly based on the conclusions of two epidemiological studies conducted in a small population of German workers, exposed under abnormal conditions of use. The results of these studies are not supported by the results from several large cohort studies conducted on several thousands of people, which show no relationship between exposure to TRI and an increase in cancer. The EU Working Group also ignored the severe criticism of the German studies by several leading epidemiologists. However, the debate is closed and the Technical Progress Committee (TPC) has voted to accept this on the recommendation of the Classification Working Group, along with a package of many other substances.
Despite all the good properties that would encourage me to continue to use TRI, is it still responsible to have my workers exposed to TRI?TRI has been used extensively for many decades. During this time, the only fatalities or serious injuries that have occurred have been due to massive over-exposure through a total disregard for good operating practices, or through deliberate misuse. When TRI is stored, used and disposed of correctly, there is no risk to human health. Animal studies have found that TRI can cause cancer in some strains of rats or mice at high exposure levels bearing no relevance to human risk assessment. The available epidemiological data do not indicate either a causal or a statistical relationship between exposure to low levels of TRI and cancer in humans. Solvent manufacturers who are members of ECSA and their distributors have made a public commitment to assist their customers to use chlorinated solvents safely and responsibly. This commitment extends to providing literature, training on handling, storage, use, recycling and safe disposal of spent solvents and wastes which arise from its use. As the producers of trichloroethylene, you are bound to oppose any adverse regulation change because of your vested interest, so why should I believe you?We all believe in Responsible Care�, because we know that this is essential for long-term business benefit. TRI can be used safely in terms of health, safety and environment if following standard guidelines. What are typical applications where TRI can not be substituted?Cleaning with TRI is essential in many industrial processes, particularly in high tech applications such as aerospace manufacturing, automotive safety equipment and precision instrument production. In these processes, TRI is indispensable for maintaining an effective production with high product performance and competitiveness on a world scale. Case study 1TRI is used in manufacturing of high-precision tools with movable parts requiring less than 4-micron tolerances. Cleaning is essential and needed in several process steps. Already minor surface alterations lead to uncontrollable quality losses. Over more than 10 years, several alternatives have been tested with the result that TRI cannot be substituted without severe quality diminution and loss of world leadership and competitiveness. The company has 2000 employees and is operating 17 cleaning machines at its German site. Heavy investments in enclosed machines over the last ten years have reduced the consumption from originally about 200 t/yr. to 5 t/yr. today. The cleaning efficiency has been steadily increased and today goods worth about 400 million EUR/yr. are cleaned consuming 5 t TRI/yr. The worker exposure is far below the MAK value, and emissions in the atmosphere are negligible. Substitution would cause loss of competitiveness and have higher ecological impacts. Substitution of TRI forced by its reclassification and re-labelling to R45 in conjunction with the VOC Directive would lead to a turnover loss of about 400 million EUR/yr. with all its consequences. In addition, planned investments of about 1.25 million EUR to further reduce the solvent consumption would not be spent. This impact is out of all proportion with the rather weak scientific base for the reclassification. Case study 2A UK-based company uses TRI in the production of professional electron devices for incorporation in a range of civil and medical applications. The company operates two manufacturing sites in the UK employing 1400 people, and has an annual turnover of �100m. In 1999 they consumed 36 tonnes of trichloroethylene cleaning precision-machined components. This level of consumption will further decline as the company makes necessary further improvements to meet the requirements of the VOCs Directive. The company continues to use TRI, despite having investigated alternative cleaning processes, because their products require an exceptional degree of internal cleanliness, which if not achieved significantly reduces the lifetime of the products in use. Should they be prohibited from using TRI through the reclassification, the company estimates it will need a 12 month programme to evaluate and establish an alternative cleaning process, with a replacement capital cost of �250k. However, they also believe that the substitute process represents a significant risk to the product lifetime performance, which would make their products uncompetitive against those manufactured outside the EU where the use of TRI will continue. What are the occupational exposure limits?The exposure limits in the table below are currently unchanged:
Key: It is likely that DG Employment will establish new Europe-wide binding limits to take this classification into account. How can I help and find out more?You can help protect your business by addressing the regulators, and providing information to us of the issues that you will face if you are forced to substitute for TRI. For further information, you may contact your supplier of TRI or any of the manufacturers, or call: ECSA Revised April 2007
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