Yes, the substance must be disclosed on the the safety data sheets (SDSs) as there is no threshold limit for disclosing substances with a Union (Community) workplace exposure limit on the SDS of hazardous mixtures.
For mixtures meeting the criteria for classification in accordance with Regulation (EC) No 1272/2008 (CLP Regulation) – ‘hazardous’ mixtures – substances for which there are Union workplace exposure limits need to be indicated on the SDSs, together with their concentration or concentration range in that mixture. No threshold limit for disclosure is provided in Annex II to the REACH Regulation – Requirements for the compilation of safety data sheets, as last amended. This means that these substances with Union workplace exposure limits must be disclosed on the SDS of a hazardous mixture, whatever its concentration in that mixture.
On the other hand, there are threshold limits for disclosing substances with Union workplace exposure limits on the SDSs of non-hazardous mixtures.
For mixtures that do not meet the criteria for classification in accordance with the CLP Regulation – e.g. mixtures not classified as hazardous – substances for which Union workplace exposure limits have been assigned must be indicated, together with their concentration or concentration range, on the SDS of the mixture, in case their individual concentrations equal or exceed the defined threshold limits. These threshold limits are 1% by weight in non-gaseous mixtures and 0.2% by volume in gaseous mixtures.
Note that these thresholds can only be applied for non-hazardous mixtures. For hazardous mixtures, no thresholds for disclosure substances with Union workplace exposure limits are allowed. Such concentrations (or concentration ranges) need to be disclosed on the SDS for the hazardous mixture.