EPA’s compilation of the public TSCA Inventory information is updated twice a year to include new and corrected TSCA Inventory chemical listings, and it contains none of the chemical identities claimed as confidential. Thus it is not as complete nor current as the information contained in EPA's TSCA Master Inventory File, which includes the chemical identities claimed as confidential and is updated continuously as new and corrected information is received by EPA. Consequently, for the purposes of TSCA compliance, the TSCA Master Inventory File maintained by EPA's Office of Pollution Prevention and Toxics is the only complete and accurate source that can provide authoritative and conclusive information about which chemical substances are currently included in the TSCA Inventory.

美國環(huán)保局對《有毒有害物質(zhì)清單》公開信息的匯編每年更新兩次，以包括新的和更正的《有毒有害物清單》化學(xué)品清單，其中不包含任何聲稱保密的化學(xué)品身份。因此，它不像美國環(huán)保局TSCA主清單文件中包含的信息那樣完整和最新，該文件包括被聲稱為機密的化學(xué)品身份，并隨著美國環(huán)保局收到新的和更正的信息而不斷更新。因此，為了符合TSCA，由美國環(huán)保局污染預(yù)防和毒物辦公室維護的TSCA主清單文件是唯一完整和準(zhǔn)確的來源，可以提供關(guān)于哪些化學(xué)物質(zhì)目前包含在TSCA清單中的權(quán)威和結(jié)論性信息。

一旦環(huán)保局收到完整的NOC，報告的物質(zhì)就被視為清單上的物質(zhì)，并成為“現(xiàn)有化學(xué)品”。環(huán)保局每年收到大約400個NOC，因此TSCA清單幾乎每天都在變化。