Petroleum Substances and REACH
Petroleum substances registered in REACH have a total tonnage of 971 million tonnes per annum (tpa) based on 2013 data.
In 2016, ECHA formed the Petroleum and Coal Stream Substances Working Group (PetCo WG) with representatives from ECHA, European Commission, Member States and industry stakeholders including Concawe, with a mandate to develop the approach for assessment of petroleum substances for potential Substances of Very High Concern (SVHC) status.
The SVHC roadmap agreed highest priority should be given to screening petroleum substances with widespread uses (professional and consumer uses and use in articles) for SVHC properties. Industrial uses are in scope of the SVHC roadmap, but the current view of ECHA is that appropriate risk management measures are correctly applied in industry. Petroleum substances which are only used as a fuel or as an intermediate or for industrial uses were assigned a lower priority and it was confirmed that substances which only had fuels uses were outside the scope for authorisation.
For 2017, PetCo WG agreed a new mandate for the prioritisation of substances and coordination of assessment activities. This will focus on the 44 petroleum substances with widespread uses and a total volume of 38 million tpa (2013 basis).
Petroleum substances are UVCBs
The REACH Regulation is relatively straightforward for single chemical substances such as Sulfur and some of the mono-constituent petroleum gases. However, most petroleum substances and many other natural products have multiple constituents. Petroleum substances are archetypal UVCBs or substances of Unknown or Variable composition, Complex reaction products or Biological materials.
The biggest challenge in applying REACH to petroleum substances is to account for their UVCB nature. The complexity of UVCB substances means it is impossible to determine the precise chemical composition to the level of each constituent. The variability in detailed composition and the large number of constituents which could reach over a million molecules makes it difficult to represent the composition of petroleum substances at such a detailed level.
For many applications of petroleum products, a detailed chemical composition is not necessary, because industry practice is to manufacture and market petroleum substances according to physico-chemical parameters specified in European Standards. Different samples from the same process in a refinery will show some variability in detailed composition, whilst still remaining within the specifications that identify the substance.
Substance sameness and read-across
Very few of the 191 petroleum substances registered under REACH have a complete data set generated for the individual substance.
ECHA criticised the petroleum substance dossiers for the lack of detail on chemical composition necessary to prove registrants have registered the same substance and therefore data collected on one sample from one registrant can apply to all registrants of the same substance and also to closely related substances.
In the initial registration process, read-across of data from one substance, where the data was measured or experimentally derived, to related substances was used widely for petroleum substances. Given that many petroleum substances are chemically similar this was considered to be fully justified.
However, in their testing proposal evaluations, ECHA challenged the read-across assumptions made at the time the substances were registered. Additional data is needed to describe the chemical composition in more detail to justify application of the current available hazard data between related petroleum substances.