About list matching

A status pill beside a substance means one thing: that list has a current entry for it, reached by an unambiguous identifier match. Every other state renders no pill at all.

The silence is the part that matters. No pill is never a claim that a substance is absent from a list, and it is never a clean result. It means the pill's own test was not met, and several kinds of real hit fail that test: a formerly listed entry, a match against a related form, a name-only match, and a group listing. Each of those is reported in full by the tool itself, where there is room to qualify it. A four-character label has no room to qualify anything, so it stays quiet.

A list can cover a substance without naming it, by listing a group that the substance belongs to. The tools report that as a group listing and name the group entry, so you can read it and decide whether it covers your material.

The membership itself comes from a curated group-alias table maintained here, because the source list carries no identifier for the group entry. That is why a group listing is reported as something to review rather than as a plain match: the group entry is the publisher's, the membership is ours.

Lists frequently name a parent compound, a salt or ester of it, or a defined family, each under its own identifier. A query that reaches a related entry rather than the substance you asked about is reported as a qualified match, with the related entries named.

The tool tells you what it found and stops there. Whether your material is the listed form is a reading of the entry against your specification, and it is not a lookup. The entries are shown precisely so that reading can be done against the publisher's own words.

A list can carry an entry for a substance that is no longer listed. Those entries are present in the data held here and are reported as formerly listed, with the date. They are never reported as a current listing, and never dropped as though the substance had simply never appeared.

A substance can also hold both a delisted entry and a separate current listing at the same time. In that case it is currently listed. The answer is about the substance, not about a single row.

Schedule 1 to the Canadian Environmental Protection Act, 1999 identifies substances by name, description and molecular formula. No entry on it carries a CAS number. Matching against Schedule 1 is therefore name-level and requires review, and no CAS lookup against the schedule itself is possible.

A separate CAS mapping published by Environment and Climate Change Canada is used where it reaches a substance, and that mapping is explicitly non-exhaustive. A substance the mapping does not reach is reported as having no CAS association, never as absent from the schedule: an absence of evidence is not presented here as evidence of absence.

Schedule 1 is reproduced under the Reproduction of Federal Law Order. The statutory schedule is published at https://www.canada.ca/en/environment-climate-change/services/canadian-environmental-protection-act-registry/substances-list/toxic/schedule-1.html.

Review is not an error, and it is not a maybe. It marks a result that is a real hit of a kind a one-word verdict would misreport: a formerly listed entry, a qualified match against a related form, a name-level match, or a group listing.

Each of those needs a person to read the entry and decide whether it describes their material. A result marked Review has more information behind it, not less.

The non-confidential TSCA Inventory file records each listing as ACTIVE or INACTIVE. Both are listings. INACTIVE describes the substance's commercial-activity designation on the Inventory. It is not a hazard, and it is not a statement that the substance is unregulated: an inactive substance is on the Inventory.

Absence from the file is a different answer again, and it does not prove absence from the Inventory. The confidential portion of the Inventory carries no CAS numbers at all, so nothing here can search it.