This program is mandated by Section 5 of the Toxics Substances Control Act (TSCA). The New Chemicals Program functions as a gatekeeper which can identify conditions-up to and including a ban on production-to be placed on the use of a new chemical before it is entered into commerce.
Currently, the newest version is MS Word 2010. Same with all the other different MS applications (PowerPoint, Excel, etc.)
Both are Microsoft Word document files. .docx is the new file extension that newer Microsoft Word version uses while the older versions save word files as .doc files. Making the world better, one answer at a time.