How to Quickly Identify PFAS in Your Supply Chain Using the US EPA CompTox Dashboard

Impending regulations and the threat of product liability are sending companies scrambling to identify the PFAS (per- and polyfluoroalkyl substances) in their supply chains. For example, the US EPA's TSCA 8(a)(7) reporting rule for PFAS is requiring manufacturers and importers, large and small, to report the use of certain PFAS in their products over the last 12 years! Reporting begins May 8, 2025.

The recent class action lawsuit against Costco and Nice-Pak Product's baby wipes demonstrates the risks of continuing to use PFAS, even if it's still "technically legal". It is really hard to justify green product claims if your product contains PFAS.

Considering the regulatory and reputational risks, it is imperative that companies take an accurate inventory of their PFAS footprint! This is also happens to be the necessary first step in finding safer, PFAS-free alternatives.

Cataloging PFAS in a company's supply chains is no easy feat. The limited chemical disclosure across supply chains has been an issue for decades, meaning many product manufacturers are not fully privy to the exact chemical identities in the materials they acquire for their products. This is an issue that effects many types of toxic chemicals beyond flourinated chemicals, but the PFAS issue further demonstrates the need for increased transparency.

So what's to be done?

I recently posted a 7-minute video tutorial on LinkedIn demonstrating how product managers and stewards can rapidly screen their chemical inventories against known lists of PFAS using a free tool that doesn't even require a login. The video can be viewed below, but this accompanying article will dive a little deeper into the how's and why's. It can bookmarked for future reference and can be easily shared throughout the community.

Gather Your Resources

First, ensure you have a complete or nearly complete inventory of chemicals in your products. This is easier said than done, but if you've been engaging your suppliers about the presence of PFAS in your products and are keeping your records up-to-date then you should be in good shape.

If you are working off chemical management system (CMS) (and I really hope you are), then you'll need to export your complete list, or as complete a list as possible. The three primary fields you'll want to obtain are:

1. CAS RN (Chemical Abstracts Service Registry Number)
2. Chemical Name (the more systematic, the better)
3. Molecular Formula

The reason you need multiple fields beyond CAS number is because not all PFAS have CAS numbers and not all PFAS have defined structures. Since disclosure of chemical identity across supply chains is often incomplete, so it's important to work with what you have.

I want to ensure that you can confidently identify both discrete and non-discrete PFAS. Make sure this list is in a pastable, tabular format, like Excel, with one line per chemical identifier.

The EPA CompTox Dashboard PFAS Chemical Lists

Once you have your inventory list, head over to the US EPA CompTox Dashboard. This tool is capable of so much that can't be covered here, and the best part is, it's completely free to use. You don't even need a login.

The chemical lists on the CompTox Dashboard are extremely useful, but querying these lists requires a little streamlining.

There are over 500 unique, curated lists, with over 53 related to PFAS. So, which one do we choose?

I recommend using the most comprehensive discrete lists and those that can identify PFAS without reliable CAS numbers or structures. For that, I would suggest the following:

- PFAS8a7: The most up-to-date list of reportable substances under the EPA TSCA Section 8 rule. However, it doesn't include UVCBs (unknown or variable composition, complex reactions products or biological materials) and polymers. That's important because the market is quickly shifting toward polymeric PFAS.

- PFASOECD: The OECD's Comprehensive Global Database. While not as comprehensive as PFAS8a7, the identities are highly curated and will conform to the OECD's PFAS definition.

- PFASStruct: A broad structure-based list based on substructure filters and %fluorine.

- PFASDev: Helps capture PFAS without explicit structures based on naming substrings and also captures polymers and UVCBs.

Details on the list descriptions can be found here: https://comptox.epa.gov/dashboard/chemical-lists

You can also choose to search against all PFAS lists if you want to leave no stone un-turned, but be aware that the results will be complicated and hard to visualize manually. That being said, if you have access to a data analyst or you plan to re-upload the results into your CMS then this option may be appealing to you. I encourage you to research these lists and pick out any that you think are most relevant to your needs.

Ultimately, this set of four should cover you for most of what's currently known and documented in the PFAS universe.

Step 1. Run the Batch Search on the EPA CompTox Dashboard starting with CAS RN

1. Click on Batch Search: For this demo, we'll be searching in three rounds, starting with the highest confidence substance identity and working our way down.

2. Enter your inputs: Start with CAS numbers, one per line.

3. Select Choose Export Options: This is very important because this will show you definitively where your substances are tagged as PFAS and where they're not. Selecting "display all chemicals" will give you results in your browser, which will not clearly show your list hits.

4. Select Your File Type: Excel is easiest, but you can choose whichever works best for you.

5. Customize Your Export Results: Focus on "presence in lists" and select the 4 lists described above (or whichever additional or alternative lists fit your needs).

Step 2. Run the List Against Chemical Name

For name searching, follow the same procedure. Just make sure to change your input field to "Name".

Just note that that this search will be less reliable as your synonyms may not match what's in the CompTox database. However, if a chemical name is all you have, it's better than nothing.

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Step 3.? Run the List Against Molecular Formula

This is why I recommend doing a molecular formula search to help fill your gaps.

To do this, change your input field to "Exact Formula" and run the search again with the same selections.

While you will get a "one to many" result based on your inputs, you will still be able to correctly tag substances in your inventory based on this basic chemical structure. This is extremely helpful, especially if you don't have a reliable chemical identity, but say for example, a molecular formula was disclosed in an SDS.

A Note About Uncertainties

While this search strategy is broad, it is not bulletproof. There are some notable uncertainties:

1. Accuracy of Chemical Identity: The quality of the results depends on the accuracy of your chemical identity and breadth of your inventory. You're essentially searching against "known-knowns". If there are hidden PFAS in your inventory that haven't been disclosed to you, this method won't help you identify them.

2. Evolving PFAS Landscape: These PFAS lists are constantly evolving and changing. You may have PFAS in your inventory that are not yet known to the wider community. This is why it's important to re-search your inventory regularly.

3. Regulatory Definitions: Regulatory definitions of PFAS vary. If something is tagged as PFAS in one of these lists, confirm that it meets the regulatory definition of interest.

Now Start Thinking About Substitution!

If you've found PFAS in your inventory, then you're likely headed toward substitution due regulatory mandates or market demand for PFAS-free alternatives. I highly encourage you to look into substitution even if your substance is not a regulatory risk. Luckily, that's my specialty. So if you're ready to move beyond regulatory compliance, then feel free to contact me.

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