The Technical Committee of Petroleum Additive Manufacturers in Europe (ATC)

The ATC was established in 1974 for member companies to discuss topics of a technical and statutory nature of common concern. The ATC works to develop industry responses to legislation that are based on sound scientific and technical principles, to the benefit of end consumers and environmental protection. The ATC SDPA Task Force represents manufacturers of SDPA antioxidants, as well as immediate formulators of SDPA-containing additive products that are sold to producers of lubricants and fluids intended for engines, power transmission and for a range of other industrial uses.

The ATC SDPA Task Force has prepared this article in response to an earlier article published in Lube Report (Risks Declared for Two Diphenylamines, Tim Sullivan, April 16, 2024).

Proposed EU Harmonized Classification and Labelling (CLH)

In May 2023, within the framework of the EU Classification, Packaging and Labelling (CLP) Regulation (EC 1272/2008), France submitted two Harmonised Classification and Labelling (CLH) dossiers to the European Chemicals Agency (ECHA) for two SDPA antioxidant substances. The proposals can be summarized as illustrated in Table 1 (alongside the current classification supported by all members of the ATC SDPA Task Force):

Table 1. CLH Proposal Summaries 

Consequences if the Proposed CLH for Each Substance Is Implemented

ATC believes that the proposed CLH for both substances is not scientifically justified based on the available toxicology data and that the proposed Repro. Cat. 1B classification will lead to an unwarranted and overly conservative restriction on the use by consumers of a majority of engine oils (where the substance is present at greater than any specific concentration limit set, or at ≥ the generic concentration limit of 0.3% – REACH Annex XVII entry 30). This will lead to a removal of consumer products from the market, so preventing consumers from changing and “topping-up” their own oil in a home setting. In addition, a Repro. Cat. 1B classification may also bring a later authorization or restriction on professional and potentially industrial uses.

In addition, the proposed CLH for the C9 SDPA (EC 701-385-4) as Aquatic Chronic Category 1 with an M-Factor of 10, will lead to most downstream lubricant oils being classified as Dangerous Goods. This will bring additional storage and transport controls as well as, potentially, a constraint on the availability of the specialist transport required for the total volumes of impacted products in the market.

The proposed CLH will have a major impact across multiple industry sectors (see Appendix A). These substances have proven to be highly effective antioxidants for lubricants, essential for transport, power generation and a range of other industries. Use of these antioxidants allows equipment and vehicle manufacturers to comply with stringent fuel efficiency and emission targets, to enhance hardware durability, and to reduce the use of chemicals and mineral oils due to extended drain intervals, thereby benefitting the European economy, society and environment, as well as contributing to the sustainability goals of the EU Green Deal.

It is highly unlikely that alternative antioxidants with equivalent cost and performance characteristics and improved hazard profile would be available in the volume that industry and society require by the time the proposed CLH and associated consumer restriction enters into force. There are no obvious candidates currently on the market, while the development of new additives would take many years to test, register and commercialize, with no guarantee of equivalent performance or improved hazard profile. This may lead to the adoption of inferior products, which could bring more severe environmental and health impacts and sustainability deficits (i.e., “regrettable substitution”). In addition, the development of new chemistries and reformulation (whether based on novel or existing antioxidants) and subsequent qualification by original equipment manufacturers (OEMs), would require the investment of a significant amount of time and money (many years and millions of euros). Therefore, the proposed CLH will lead to significant impacts on downstream producers of lubricants and their OEM customers in a relatively short timeframe.

The CLH process and estimated timings for impact is illustrated in Figure 1.

Figure 1. Estimated Timing for Impact

ATC Position on the Proposed CLH

For both substances, ATC disagrees with the assessment of the existing data by the Member State submitting the CLH dossiers and does not consider the proposed CLH warranted.

The detail of ATC’s rebuttals of the toxicological basis of the proposed CLH (as submitted through the Public Consultation) can be seen on our website (https://www.atc-europe.org/publications.asp), but to summarize, most of the evidence put forward by the Dossier Submitter (DS) on the reprotoxic effects of the C9 SDPA, are based on data available for the C4:C8 SDPA. While it is true that read-across from the C4:C8 SDPA was originally proposed by EU REACH Registrants to minimize animal testing and meet the REACH 2010 registration deadline, since that time, new reproduction and developmental screening toxicity studies have been conducted (OECD Testing Guideline 421, 2020) that challenge the viability of the earlier read-across position. The data obtained from the OECD 421 studies show distinct response differences between the two substances. Therefore, read-across for the reproductive and developmental endpoints from data on the C4:C8 SDPA to the C9 SDPA is no longer considered reliable.

As the data from the OECD TG 421 studies call into question the validity of the earlier read-across approach, the Lead Registrant submitted a testing proposal for an Extended One-Generation Reproduction Toxicity study (OECD TG 443) with the C9 SDPA substance on October 6, 2021. Following a public commenting phase, no further steps have been taken by ECHA in the testing proposal evaluation process. The Registrants believe that this study is necessary in order to properly evaluate the reprotoxicity of the C9 SDPA. Since this study is also required for registration in jurisdictions outside of the EU (e.g., for Korea-REACH), members of the ATC SDPA Task Force have, in any case, had to commission a full OECD TG 443 test and have also initiated an enhanced OECD TG 421 study to include additional mechanistic examinations. Since these studies will deliver additional data to clarify the reprotoxicity of the C9 SDPA, in its Public Consultation submission, the ATC has asked that these additional data be considered during the RAC Opinion development.

ATC Advocacy

The ATC SDPA Task Force submitted extensive rebuttal comments challenging the toxicological basis of the proposed CLH for both substances through the public consultation process. In addition, supported by our consultants, the ATC sent a communication package to downstream industry stakeholder organizations representing formulators of lubricants and OEMs, national associations and individual companies, inviting all to submit comments through the Public Consultation.

Our consultants have also carried out a full Socio-Economic Analysis to inform our advocacy messages on the consequences of the loss of these antioxidants from the market, in the event of any restriction triggered by a Reprotoxicity Cat. 1B CLH (i.e., no viable alternatives, sustainability deficits, financial costs, potential unemployment, etc.), as well as the impact that the proposed Aquatic Chronic Cat. 1 / MF10 CLH will bring in terms of a dangerous goods classification for the C9 SDPA (increased costs, controls and potential transport capacity limitations). These socio-economic messages of significant negative impact, along with ATC’s position on the toxicology underlying the proposed CLH, will be presented by ATC and our consultants in advocacy meetings with the authorities.

Our plea to readers of this article is, if you represent a company likely to be impacted by the proposed CLH on these substances and you have contacts in the relevant EU Member States where you operate, to please express your concerns and support for the ATC position.

Conclusion

To summarize, it is the view of the ATC that an overly precautionary CLH based on technically unjustified assumptions and interpretations of an incomplete toxicology dataset should not be implemented. If the CLH is implemented as proposed, there may be regrettable substitution with inferior products and significant socio-economic impacts across multiple supply chains and sustainability deficits, which are inconsistent with the principles of the EU Green Deal.

The Technical Committee of Petroleum Additive Manufacturers in Europe (ATC) was established in 1974 as an avenue for member companies to discuss topics of a technical and statutory nature.