The effects of new legal rules on the use of metal working fluid (MWF) containing boric acid
Firstly, perhaps the most important statement: the use of boric acid in MWF concentrates and the use of water-mixed MWF containing boric acid is allowed, and will remain so for the time being. A few changes will however be required of both the makers and users of MWF, in terms of categorisation, labelling and risk assessment, and of communication along the supply chain.
The legal framework
According to the European CLP(1) regulation (1272/2008/EG), the transitional period for the new categorisation of boric acid expired on 1 December 2010. Since then, boric acid and preparations that contain more than 5.5% boric acid have to be classified and labelled as toxic to reproduction, category 2.
Categorisation and labelling:
Toxic to reproduction, category 1B
(A material that is probably toxic to reproduction)
H 360F (can impair fertility)
H 360D (may harm the unborn child)
Signal word: Danger
Since June 2010, boric acid is also in the SVHC(2) list of candidates according to articles 57 and 59 of the REACH regulations. This list contains materials that will be subject to special examination by the EU authorities to assess the risk to human health and to the environment. As boric acid is now on the SVHC list of candidates, it must be decided whether boric acid should be subject to approval. The various applications in industry, of substances subject to approval, must be registered. Under certain circumstances, approval may not be granted for one, for several or for all applications so that, from a certain point in time, sales may be restricted or even completely forbidden. The possibility that boric acid may become a substance subject to approval in the future cannot be ruled out. At present, it is difficult to assess whether its use in MWF would be approved, but it is not unlikely.
Special aspects to be considered when using water-miscible MWF that contain boric acid
The key aspect in the decision as to whether MWF containing boric acid is categorised as toxic to reproduction is the amount of free boric acid. If the amount of free boric acid is below 5.5% but above 0.1%, then in chapter 15, boric acid is to be displayed as an SVHC substance, and in chapter 3 as a substance toxic to reproduction marked with T R60/61, but the product will not be labelled as a hazardous preparation.
Users of cooling oil containing boric acid should, for example, ask their supplier for an up-to-date safety data sheet showing that the product is below the 5.5% threshold and thus does not have to be labelled. Please note that it is mandatory to mention boric acid as a hazardous substance in the safety data sheet since 1st December 2010.
In all Oemeta MWF, the amount of free boric acid is considerably less than 5.5%, which means that it is not necessary to label the MWF concentrate as a hazardous substance. Oemeta supplied appropriate proof as part of a joint study with VSI(3), VKIS(4), BG Metall Nord Süd(5), IG Metall(6) and well-known German manufacturers of cooling oils. In this study, over 50 MWF samples were used to make 11 Boron-NMR measurements. The aim of this investigation was to see to what extent the boric acid used in the formula reacts with the alkalis also contained in the product. Only the free boric acid that has not reacted is considered when categorising and labelling the preparation. The amount of free boric acid was always considerably less than 5% but above the threshold for consideration of 0.1%.
Since March 2007, in Germany a health-based occupational exposure limit of 2.6 mg/m3 for boric acid in ambient air has been in force. By definition, if an occupational exposure limit is adhered to, no acute or chronic damage to the health of employees is to be expected. Initial measurements have shown that even when handling crystalline boric acid during the manufacture of MWF concentrates, the threshold is not exceeded. For the user, this means that when using unlabelled MWF containing boric acid in machining systems where MWF aerosols are minimised as far as possible, any risk to employees from boric acid’s toxic effects on reproduction can be ruled out.
Pursuing the aim of optimal communication along the supply chain, Oemeta is actively notifying its customers about the facts mentioned above. In August 2010, all users of Oemeta MWF containing boric acid received a safety data sheet conforming to CLP.
For more information on this subject, please see:
(1) CLP = Classification, labelling and packaging of chemicals
(2) SVHC = Substances of very high concern
(3) VSI = Verband Schmierstoff-Industrie (German association for the lubrication industry)
(4) VKIS = Verbraucherkreis Industrieschmierstoffe (German group for users of industrial lubricants)
(5) BG Metall Nord Süd = German Employers Mutual Insurance Association Metal Industry
(6) IG Metall = German Labour Union Metal Industry