Section 12 – Ecological Information: Where Impact Becomes Responsibility
Understanding what your SDS really says about the environment
When most people open an SDS, they jump to the parts that protect people, first aid, PPE, fire response.
But Section 12 is where the focus shifts outward. It describes how the substance behaves once it leaves the site.
For SHEQ managers, Section 12 is not a formality. It is the place where compliance meets conscience, where chemical data becomes environmental impact.
Why Section 12 Exists
Section 12, Ecological Information, summarises what is known about a product’s behaviour in the environment.
It supports decisions on storage, waste handling, emissions control, and spill response.
Under REACH and CLP, suppliers must include data that allow downstream users to understand a substance’s persistence, bioaccumulation, and toxicity, the famous “PBT” trio, plus information on how it degrades and moves.
In short, it helps you predict what happens when chemistry meets ecology.
What You’ll Find in Section 12
Most SDSs include:
- Toxicity data – aquatic short-term and long-term results (fish, algae, daphnia) expressed as LC₅₀, EC₅₀, or NOEC values.
- Persistence and degradability – whether the substance breaks down biologically or chemically.
- Bioaccumulative potential – log Kₒw or BCF values that show whether it builds up in organisms.
- Mobility in soil – log Koc, solubility, and leaching behaviour.
- Results of PBT/vPvB assessment – if relevant, conclusions from REACH dossiers.
- Other adverse effects – ozone depletion, endocrine activity, or, more recently, PMT/vPvM properties.
That last item is increasingly important. Since 2023, the EU has added PMT (Persistent, Mobile, Toxic) and vPvM (Very Persistent, Very Mobile) as new hazard classes in CLP.
We covered these in detail in our recent article PMT & vPvM – The New Environmental Risk Flags in CLP.
Component Data vs Mixture Data
One of the most misunderstood aspects of Section 12 is that the information is usually derived from the individual components, not the finished mixture.
In most cases, only pure substances are tested for biodegradation, bioaccumulation, or aquatic toxicity.
Testing every possible mixture would be impractical and, under REACH, is often unnecessary.
So, for a mixture, the supplier uses data from each component to estimate the environmental behaviour of the product.
They apply weight-based calculation rules, bridging principles, or read-across methods to determine expected aquatic toxicity or persistence.
This means:
- The numbers in Section 12 rarely come from tests on the final formulation.
- They represent a worst-case or calculated profile based on the hazardous components.
- Results can vary significantly depending on how the SDS author applies these methods.
Where the Data Come From
For registered substances, the source data come from REACH registration dossiers submitted to ECHA.
These contain experimental results or validated QSAR model outputs for properties such as:
- Ready biodegradability (OECD 301 tests)
- Bioaccumulation (BCF, log Kₒw)
- Aquatic toxicity (OECD 201, 202, 203)
- Soil and sediment half-lives (OECD 307, 308)
This information is publicly available in the ECHA substance database under the “Environmental fate and pathways” and “Ecotoxicological information” tabs.
So if a value in Section 12 looks unclear or generic (for example, “no data available” or “not readily biodegradable”), it is worth cross-checking the REACH registration entry to understand the data source.
Why It Matters
For SHEQ professionals, Section 12 is the key to:
- Evaluating environmental risk before substances ever leave the site.
- Supporting environmental permits and wastewater discharge limits.
- Planning emergency measures for spills and leaks.
- Choosing safer substitutes based on persistence and mobility.
If Section 12 is blank, vague, or inconsistent between suppliers, it is a red flag.
It means you cannot accurately assess downstream impact, and it is time to request an updated SDS.
The NextSDS Approach
At NextSDS, we extract and structure all Section 12 data, from toxicity endpoints to degradability and mobility, so SHEQ managers can:
- Compare environmental profiles across suppliers.
- Flag missing or outdated ecological information.
- Automatically detect substances that may qualify as PMT/vPvM under the new CLP criteria.
- Link Section 12 data back to REACH dossier entries for verified source information.
- Integrate this data into environmental reporting and sustainability KPIs.
✅ Section 12 is where the story of a substance meets the story of the environment.
When we understand it well, we do not just stay compliant, we stay responsible.
👉 Want to see how NextSDS can turn your SDS data into actionable environmental insight? Get in touch.