The National Chemicals Inventory of The Department of Industrial Works (DIW-TECI) had 11,479 substances as of June 2022, covered hazardous substances type 1 (40 substances), type 2 (82 substances), type 3 (306 substances) and type 4 (4 substances). However, the authors had checked the Official Gazette Notification on the List of Hazardous Substances, which contained 141 substances for Type 1, 47 for Type 2, 514 for Type 3 and 120 for Type 4 under the Ministry of Industry, suggesting that some categories had still under evaluation.　The Ministry of Industry was currently carrying out risk evaluation of all substances included in the DIW-TECI based on its own judgement. However, as shown in Table II‑1, as of June 2022, 9,290 substances has been under risk evaluation, representing a progress rate of approximately 19%　and appeared to be no remarkable progress on September 2024[１].

Substances in DIW-TECI were divided into four categories: Inorganic substance, Organic substance, Polymer, Substances under risk estimation. Each category had 4 sub-categories including Chemicals of Concern (CoC), General Chemicals (GC), Low Concerned Chemicals (LCC) and chemicals under risk evaluation. LCC was a substance for which no further ongoing assessment will be carried out due to low risk as a result of the risk assessment　by related agencies. The GC was a substances that may be transferred to CoC or CHC as a result of risk assessment by the related agencies. The CoC and CHC were intended to be transferred to further tighten the regulations.