The short answer
Under the EU's REACH rules, the most worrying chemicals, including carcinogens, can be named Substances of Very High Concern. Named substances go on a public candidate list. Companies that sell products containing them above 0.1% by weight must pass on information, and consumers can ask about them.
SVHCs are the most concerning chemicals under REACH.
Carcinogens, mutagens, and reproductive toxicants (CMRs) can qualify.
SVHCs go on a public 'candidate list.'
Listing triggers duties for companies to share information about products that contain an SVHC above 0.1% by weight.
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This page explains the EU's list of its most worrying chemicals. It covers who qualifies, what companies must do, and what you can ask as a consumer.
The EU's watch list for the worst chemicals
Inside REACH, the EU marks out its most worrying chemicals with one label: Substances of Very High Concern (SVHCs). Carcinogens can qualify.
What qualifies as an SVHC
Published research on the process describes these groups of substances:
- CMRs. These are carcinogens, mutagens and reproductive toxicants. Carcinogens are a core group here.
- PBT/vPvB substances, which last a long time, build up in living things, and are toxic.
- Substances that cause similar concern, such as endocrine disruptors.
A chemical classed as a carcinogen is therefore a natural candidate for SVHC status. See CLP for how the EU classifies chemicals.
The candidate list
Once named, an SVHC goes on the candidate list, a public register. Because it is public, information about SVHCs can move through supply chains and reach consumers.
Two duties are tied to products (articles) that hold an SVHC above 0.1% by weight:
- Suppliers have duties to share information about it.
- Consumers can ask a supplier whether a product contains an SVHC. Suppliers have 45 days to answer.
Research on this right found that many requests got no answer, and many answers were vague. A reply that only says a product is "REACH compliant" does not tell you whether an SVHC is present.
What happens after listing
Being named does not by itself ban a chemical. The EU's chemicals agency, ECHA, describes the later steps that can follow, such as limits on use. We could not open ECHA's site when we checked this page, so for current details of those steps, see ECHA's explainer.
Why it matters
The SVHC process is one way the EU turns a hazard into action. A chemical named as a carcinogen can be put on a public list and given disclosure duties. That makes information about it easier to find.
The bottom line
Substances of Very High Concern are the EU's label for its most worrying chemicals, and carcinogens are a central category. The public candidate list and the duties tied to it help companies and consumers know where these chemicals are used.
Sources
Common questions
What is a Substance of Very High Concern?
Under REACH, an SVHC is a chemical with serious, often irreversible effects on health or the environment. Carcinogens, mutagens, and reproductive toxicants (together called CMRs) are a major category of SVHCs.
What is the candidate list?
A public list of substances identified as SVHCs. Being placed on it triggers legal duties for companies. ECHA, the EU chemicals agency, describes further regulatory steps that can follow; see its site for current details.
What duties does listing create?
For products (articles) containing an SVHC above 0.1% by weight, the supplier has duties to share information. Consumers can ask a supplier about SVHCs in a product, and the suppliers have 45 days to reply.
Does SVHC status ban a chemical?
Not by itself. Naming a substance is an identification step. Whether and when its use is limited depends on later decisions under REACH, which ECHA describes on its site.
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Sources last checked: 2026-08-11 what this meansLast updated: 2026-08-11Next planned review: 2028-07-05
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Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes, and this is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and then compared with the sources listed on it, looking for statements those sources do not back up. That check is not a sentence-by-sentence record and can miss errors. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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