Priority Assessment Chemical Substances (PACs) are designated after undergoing a chemical substance screening assessment by the national government. In FY2010, PACs were chosen from among substances designated as Type II and Type III Monitoring Substances. After April 1st 2010 “Monitoring Chemical Substances” became a distinct category and selection of priority substances was announced in the official gazette on April 1st, 2011 based on council discussions held in January 2011. On 27 October 2011, MHLW, METI and MOE published the " Implementations of Screening Evaluation and Risk Assessment", based on the reported amounts manufactured and imported in 2010. This publication describes the schedule for screening   evaluation of General Chemical Substances and risk assessment of PACs.

Any substance that is not on the Chemical Substances Control Law (CSCL) Inventory is classified as a "new chemical", which means that it does not have a MITI number. There are approximately 20,000 existing chemical substances that have MITI numbers in the inventory at this time.

In order to determine if the substance you are working with is a new chemical, please use CHRIP to look for the MITI number for that chemical.
When you cannot identify a MITI number for a chemical by its CAS number using CHRIP, please look for the MITI number by chemical name - you may be able to find the corresponding MITI number.
NITE does not provide any service to search for the MITI number by its CAS number.

The manufacturer and the either importer or foreign exporter, but not both must submit it. In the case of exporting new chemicals to Japan, the Japanese importer needs to do the up-front notification for new chemicals under CSCL. Exporter can replace the importer and do an up-front notification. In this case, the importer is not required to do an up-front notification.
Note that exporter can submit only regular notification.

Yes, For customs clearance, importers are obliged to indicate CSCL inventory number in an invoice or in an import document for existing chemical substances in a product. All the intentionally added chemical substances regardless of their concentrations in a product and all the other chemical substances contained 1% or more shall be indicated.

Detail requirements for the other types of chemical substances such as new chemical substances, chemical substances for R&D use, and Class I Specified Chemical Substances etc. are described in the "Notice for the customs clearance procedures for chemical substances related to the Chemical Substance Control Law (Mar.31, 2014, METI)"

However, this requirement does not apply to chemical substances in articles. Because articles are not in the scope of the definition of "Chemical Substance" under the law.

Existing chemical substances

The concept of “existing chemical substances” under CSCL is different from that in many other countries. It actually means chemicals that had been in Japan’s market before the enactment of the Law in 1973 (approximately 20,600 substances).

In the legal context, the term existing chemical substances is used in a narrow sense which refers to existing chemical substances excluding those designated as monitoring chemical substances, priority assessment chemical substances, class I and class II specified chemical substances.

• New chemical substances

They are chemicals that have never been manufactured in or imported to Japan and not been evaluated. The specification of situations where substances are not considered as new chemical substances

Chemical companies should judge whether a chemical substance is new or not by themselves. A chemical substance without an assigned MITI number (official gazette or registry number) is considered as a new substance. Please note that MITI numbers do not correspond to the CAS numbers, so there are situations where you can hardly search whether a substance has a MITI number in the ENCS Inventory, and advisory opinions from experienced experts may be needed.

When the content of an impure compound is less than one percent by weight, the compound is not regarded as a new chemical substance. An “impurity” refers to unintended substances such as unreacted raw materials, reaction catalysts, chemical indicators, and by-products generated by reactions that are not intended.

In the column for name in the list of existing chemical substances, “・”and other marks possess the following meaning:
(i) “・”generally stands for ”and”.
(ii) ”,”generally stands for “or”, except when it indicates the end of a paragraph.
(iii) When the number of substituents is not shown, the number is one in principle.