So I wanted to provide a bit of unique perspective here on the topic. I now work as a process engineer in a steel mill, but 2 of my previous positions were in product safety and regulatory compliance. I worked in US, CA, & MX regulatory law, as well as global compliance with countries outside of the Americas. In my position I had to deal with regulatory compliance with chemical lists (TSCA, ECHA, DSL/NDSL, ISHL, etc.) and I was responsible for creating and verifying the information we use to create our SDS sheets.

So a large part of people are stuck on the fact that there is a lot of redacted information in the paper, this could be for multiple reasons outside of protecting trade secrets. As I stated above, there are regulatory chemical lists. In many countries, it is entirely ILLEGAL to sell or use in manufacturing, any chemicals which do not appear on the list for the country in question. When a company wants to create a new chemical (which is happening all the time, this also can be a "mix" and not a defined exact molecule, ill speak more on this later) its is a very slow and long process of classifying the chemical, getting a CAS number assigned, and then getting this chemical listed on the regulatory lists of the locations you intend to use it/sell it. To get listed on these lists is a process in itself that includes providing absolutely as much information on the chemical as reasonably achievable. From my experience, ECHA (EU) has stricter rules than TSCA (U.S) for example, and not all lists are made equal, governed equally, or even list the same chemicals. So circling back, the feedstock listed in the paper is likely very early in this process or is in the middle of the process, meaning there is not an "official" name or means of identifying what is being spoken about, anything referred to in the paper would just be internal monikers/code names or possibly a nickname to describe it.

On the topic I said I would speak more about, "mixes" or "chemicals" without a defined chemistry. So there are feedstocks/chemicals/mixes of oils/paraffin materials/alkanes/etc. that are very hard to control the creation of, so they are created as an inseparable bulk mixture. Some Examples:

-Cas #: 85535-86-0 [C18-28 Chloroalkanes (20-50 %Cl)]

-Cas #: 97553-43-0 [Paraffins (petroleum), normal C > 10, chloro]

The "mixtures" are classified based on their properties and what is actually making up that mix defined within the certain Cas #. This is likely how all of the feedstocks in the paper would be classified. Based on certain plastics that are recycled you could expect X, Y, Z, defined blends.

Finally, regarding the safety aspect. Having been thrown into the world of chemical regulation (I am a chemical engineer by education, we covered the existence of TSCA in like one section of our safety course), I got to see first hand how almost "fly by the seat of your pants" it is. I cannot suggest a "better" way to more safely regulate these chemicals, other than to take an outright strict approach (which I am in favor of btw). Eu for example is much stricter (both health and environmental hazard wise) compared to the U.S. They have a higher burden of proof that the chemical is not harmful and an approach of "okay if it shows signs it could be a problem, classify it as such", while it sure feels like the EPA takes the approach of "okay, lets see if you guys can keep this from becoming a problem." Which companies have proved repeatedly, they cannot.