priority substance; substance requiring priority action
Technical term used in environmental regulation and chemical management to designate substances that need urgent assessment or control.
The Ministry of the Environment published a list of priority substances.
This chemical substance is designated as a priority substance.
Standard kanji form used in environmental policy contexts.
Variant with okurigana; less common but still seen in official documents.
Compound of 優先 (priority), 取組 (effort, initiative), and 物質 (substance). The term likely originated in Japanese environmental policy as a translation of 'priority substance'.