Thought Leadership: The Toxic Substances Control Act and the Bioeconomy: Part 1, The Impact of Nomenclature on the Commercialization of Biobased Chemicals; Part 2, Reportable Substances across the Manufacturing Process; Part 3, Call to Action
by Richard E. Engler, Ph.D. (Bergeson & Campbell, P.C. and The Acta Group) When I meet people from bioeconomy companies, I ask them about their products’ status under the Toxic Substances Control Act (TSCA). The most common answers I receive are: “TSCA doesn’t apply because our product is not toxic,” “TSCA doesn’t apply because our product is naturally occurring,” and “We are compliant with TSCA because we’re making something that’s already in commerce.” This usually leads to a more in-depth discussion of how TSCA works and its idiosyncrasies with respect to biobased products. I do not ask this to be accusatory, rather I want to be sure that companies understand their obligations so that they do not run afoul of the law. TSCA penalties can add up quickly (maximum $37,500 per violation per day) and can threaten nascent companies if they are not diligent.
Bioeconomy companies recognize that their products are subject to a variety of federal chemical regulations, especially if they sell food, food additives, cosmetics, or other products regulated by the U.S. Food and Drug Administration (FDA). Unfortunately, companies may not recognize all the ways that the U.S. Environmental Protection Agency (EPA) regulates bioproducts, perhaps because of the understandable focus on the Clean Air Act (CAA) and the various programs under that authority: Renewable Fuel Standard, fuel additive registration, or other CAA submissions.
TSCA also applies to bioproducts used in industrial, commercial, and most consumer products, including fuels. TSCA reporting requirements are in addition to, and separate from, CAA reporting.
TSCA requires that a company must ensure that any chemical substance it intends to manufacture (or import) is listed on the TSCA Chemical Substance Inventory (the Inventory) or be subject to an exemption before commercial production occurs. If a substance is not listed on the Inventory, the manufacturer must submit a premanufacture notice (PMN) to EPA 90 days prior to producing or importing that substance.
Triglyceride oils provide an instructive example of how the source is included in the substance identity.
Corn oil is listed on the Inventory as:
Definition: Extractives and their physically modified derivatives. It consists primarily of the glycerides of the fatty acids linoleic, oleic, palmitic and stearic. (Zea mays).
(CAS registry number 8001-30-7).
It is a distinct substance from other vegetable oils, such as:
Definition: Extractives and their physically modified derivatives. It consists primarily of the glycerides of the fatty acids linoleic, oleic, palmitic and stearic. (Soja hispida).
(CAS registry number is 8001-22-7).
The definitions of these two oils are the same, except for the source names — Zea mays and Soja hispida. Even though the two oils are often used interchangeably because they have very similar fatty acid profiles, the different sources mean that these are two different substances under TSCA. A manufacturer of one could not rely on the identity of the other for TSCA purposes. Furthermore, the source-based name may also extend into a downstream product. For example, a fatty acid methyl ester (FAME) biodiesel made by the transesterification of corn oil with methanol would be:
Fatty acids, corn-oil, Me esters
(CAS registry number 515152-40-6),
while the soy FAME would be:
Soybean oil, Me ester
(CAS registry number 67784-80-9).
These two identities are distinct and a biodiesel producer would have to be sure that the corresponding FAMEs were listed on the TSCA Inventory before making biodiesel from either corn or soybean oil. The same is true for novel sources of triglycerides, such as algae, genetically modified microorganisms, or other non-traditional oil sources, even if they are otherwise identical to existing triglycerides listed on the Inventory. The source is included in the name, so each distinct source leads to a distinct chemical identity for products.
This can lead to a headache for TSCA reporting for your customers.
Mixed biobased hydrocarbon streams from pyrolysis or reforming may be identical to petroleum refinery streams that are listed on the Inventory, but if those petroleum streams include “petroleum,” “crude oil,” or other similar terms in either the name or the definition, manufacturers of the biobased equivalent cannot use the petroleum-based names for TSCA purposes. READ MORE
“Feedstock” means something different at different points along the supply chain. At the very beginning of the supply chain for biobased chemicals and biofuels are plants (that is crops, not facilities). Plants, of course, are naturally occurring.
Some bioeconomy companies do not start with agricultural residues — some start with sugars, some start with waste. Companies may use municipal solid waste, including paper or food scraps, paper mill waste such as low-value lignocellulose waste, or waste fats and grease from commercial kitchens. TSCA specifically exempts waste from reporting, provided the waste is being disposed of as waste or incinerated. If you are using it as a feedstock, it is not waste. Your use of the waste in a commercial process means that the waste must be listed on the Inventory and the producer of that waste must report under CDR.
As with companies that rely on waste as a feedstock, companies that purchase fermentable sugars should be sure to determine the TSCA status of their feedstock. Starch, acid-hydrolyzed starch, base-hydrolyzed starch, and D-glucose are all separate identities. Your supplier should provide you with the correct TSCA identity for the product you purchase.
The next stage of manufacturing is intermediates. Intermediates are arguably the most confusing part of how TSCA regulates chemical manufacturing process.
If an intermediate is isolated, it, like the final product, must be listed on the Inventory, and we will take a look at what qualifies as “isolated” below. The most common intermediate in the bioeconomy is pre-treated biomass. Any pre-treatment, such as acidic, basic, solvent or other treatment that alters the chemical bonding of the feedstock changes the chemical identity of the feedstock. Your feedstock may be naturally occurring, but the acid-pretreated feedstock is not — it is an intermediate.
Nonisolated intermediates are exempt from TSCA reporting, but isolation may even occur if the reaction vessel is closed off from the rest of the process by valves. These distinctions are often very subtle and even counterintuitive from an engineering perspective. For example, agricultural residues are shredded and added to a reaction vessel with aqueous acid where it is stirred and heated to begin the breakdown of the lignocellulose. The resulting slurry is pumped into a fermentation vessel where it is converted to ethanol. Because the acid pre-treated biomass is pumped from one vessel to another, it is isolated and is reportable under TSCA, even if the pre-treated biomass is never exposed to air.
In the final step, an intermediate substance reacts, often with a catalyst, enzyme, or microorganism, in some solvent, to convert that intermediate into the product. Everything intentionally added to that pot must be listed on the Inventory. In many bioeconomy reactions, the solvent for this step is water. Water is listed on the Inventory, and is also a naturally occurring substance.
Another typical input in this last step is a catalyst. The catalyst must also be listed on the Inventory, whether it is a traditional metal catalyst, an enzyme, or a microorganism. READ MORE
The key is to find a way to level the field without compromising the U. S. Environmental Protection Agency’s (EPA) mission and authority to protect human health and the environment.
Fats and Oils
The most critical barrier that needs to be addressed is the inclusion of source in a substance’s identity. While the Soap and Detergent Association (SDA) nomenclature system strikes a balance between reporting and flexibility, it does not sufficiently cover the nomenclature issues related to many biobased products, as has been discussed inpast articles. The SDA system provides industry the ability to choose from among the 35 natural sources of fatty acids that meet the SDA alkyl range criteria and their petroleum equivalents.
Opening the 40-year-old list of organisms eligible to use SDA nomenclature would go a long way towards enabling novel triglyceride sources to enter commerce without triggering new chemical substance notifications throughout the supply chain. Right now, EPA has no mechanism for adding sources without conducting a full rulemaking. A mechanism that enables EPA to add sources to the SDA list as part of the premanufacture notice (PMN) review of a new source would maintain EPA’s ability to ensure new sources do not present unreasonable risk to human health and the environment, as well as lower the barrier to market adoption of these new sources.
Petroleum streams and similar hydrocarbon products present another problem. Some hydrocarbon substances do not include their source in the identity.
(CAS Registry Number 68514-38-5)
These can be made from any source, whether fossil or biomass, without triggering new chemical notification under TSCA, although caution must be used to be sure that the carbon range descriptor is accurate for the potentially new substance. On the other hand, some petroleum streams are identified with the source.
Hydrocarbons, C3-4-rich, petroleum distillates
Definition: A complex combination of hydrocarbons produced by distillation and condensation of crude oil. It consists of hydrocarbons having carbon numbers in the range of C3 through C5, predominantly C3 through C4.
(CAS Registry Number 68512-91-4)
Substances like these that are “unknown or variable compositions, complex reaction products, and biological” materials (UVCB) are, of course, complex and variable. Their exact composition may depend on variations in the source (e.g., grade of crude oil) and process conditions by which they are made (e.g., temperature). As long as the product fits the definition (other than the source) and characteristics, should the source matter?
Call to Action
Ideally, the regulated community, including both the producers and their customers, would engage with EPA to seek broad solutions, as a group, rather than individual companies seeking individual solutions. These solutions may require rulemaking and a collective approach could bring the issue to a high enough priority to justify the effort and expense for EPA to undertake rulemaking.
Although specific changes may be too arcane to include in TSCA reform, an updated TSCA could mandate EPA to update the nomenclature systems to allow source-agnostic chemical identities without compromising its ability to protect human health and the environment. The Biobased and Renewable Products Advocacy Group (BRAG), Algal Biomass Organization (ABO), Biotechnology Industry Organization (BIO), and other biofuel and biobased chemical member organizations should approach EPA and Congressional representatives to be sure their concerns are addressed. READ MORE and MORE (The Guardian)