April 2005 

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The SANSS database -- Structure and Nomenclature Search System -- underwent the most dramatic expansion in the course of this update: It increased from 516,216 records to 677,407, each record dealing with one chemical substance. The records may contain, as available:

• a CAS Registry Number

• one or more chemical names/synonyms

• a molecular formula

• a structural depiction

• a list of sources where more information can be found on the substance (on CIS or elsewhere).

We consider SANSS records to be central to our chemical-oriented databases, and that is why we have structured CIS so that any appropriate SANSS record(s) appear first in any results file, before the records associated with any other database in the system. If you're not accustomed to looking at SANSS records, you might want to review the detailed article about the update that appears below since it explains in some detail new features that we hope will make SANSS more useful both now and in the future.

A regular quarterly update to the RTECS (R) database increased the number of records in the database from 159,426 to 160,506, each dealing with one chemical substance.  (In all, some 7,700 records were altered or added during 2004.)   Another update is pending as of this writing.

We make a point of noting this update activity by way of warning you about something we recently encountered on the Web, a cut-down version of RTECS (R) that startled us despite having seen other things like it before.  In the version we recently encountered, the data were handsomely presented, and the production looked quite professional. Furthermore, the material was available for free. If you didn't look very closely, you might not realize that this is one of those situations in which "free" is too high a price.  Here's why:

• First, the data were limited to acute toxicity.  We looked at several records which ought also to have had data for reproductive toxicity, irritation, multiple-exposure effects, and so forth -- but all of that appeared to be missing.

• Second, the data appeared to be somewhere between five and seven years old.  In one case, the Web source included five acute toxicity citations -- but the current RTECS(R) record includes those five citations plus eleven others.  The eleven missing citations all date from the year 2000 or later.

• Third, the bibliographic references accompanying the acute toxicity citations were erroneous.  The producers appear to have shuffled the references in such a way that a small percentage are correct, most are lined up with data to which they don't belong, and some are simply missing.

• Fourth, the producers apparently have a processing system that overlooks details like "greater than" and "less than" symbols.  We tracked a few records that have such operators in the current raw RTECS (R) data, but they were generally missing from the cut-down Web version we were reviewing.

We know we can't claim perfection for our own efforts, but this professional-looking effort was very misleading and at times incorrect.

The number of sites/ records in the CERCLIS database increased from 45,556 to 45,941.   The number of records with lists of PRPs attached (Potentially Responsible Parties) increased from 2,939 to 3,026. (REMINDER:  When searching for the name of a company -- either as a site name OR a PRP -- SHORTER entries are better than long ones:  Thus, HAMMOND VALVE is a much better search term than HAMMOND VALVE CORP or HAMMOND VALVE CO.  This applies generally to searching for corporate/site names in any of CIS's site-oriented databases.)

The CCRIS, CRISP, HSDB, IRIS, and RISKLINE databases also were expanded modestly in the course of the recent update.

As noted above, SANSS is of central importance in CIS because it can tell you where to find the kinds of information about a chemical substance that you're looking for, whether in CIS itself or elsewhere.  After the most recent update, it covered more than 677,000 unique chemical substances.  The contents of the database are dictated by the various sources of information cited in SANSS records (as explained below); consequently, SANSS does not pretend to cover the entire universe of chemicals, only those that are of widespread commercial, regulatory or scientific interest.

There are five basic elements to a SANSS record:

• a CAS Registry Number

• one or more chemical names/synonyms 

• a molecular formula

• a structural depiction 

• a list of sources where more information can be found on the substance (on CIS or elsewhere).

Not all of the elements appear in each record. That is, a given SANSS record may have one or more chemical names, one or more references to sources of information, and a chemical formula, but lack a structural diagram.  Approximately 18.9% of SANSS records have all five elements, 56.8% have four or five elements, and 73.1% have three elements or more.

Here are some statistics on each of the five categories mentioned above:

- CAS Registry Numbers.  A CAS Registry Number is included in 97.2% of all SANSS records.

- Chemical Names.  Approximately 60% of SANSS records include one or more chemical names.  That percentage will increase in upcoming updates as additional names are added from the various Sources of Information categories mentioned below.   Furthermore, the most common substances tend to have multiple names -- systematic names, common names, trade names, even nicknames:  More than 120,000 SANSS records have three or more chemical names, and the number of records with ten or more names is around 10,900.  Approximately 115 records had more than a hundred names, and the three records with the largest assemblage of names had 489, 705, and 934 -- the bulk of them being trade names for common polymers.  [NOTE:  The major function of a chemical name in CIS/SANSS is to permit retrieval of a CAS Registry Number, which can then be used for a more complete and effective search of other databases in CIS.  Given the vagaries of chemical nomenclature, reliance on searching by chemical names is discouraged.]

Structural Diagram.  More than 265,000 SANSS records include a structural diagram.

Molecular Formula.  Approximately 71.7% of SANSS records include a molecular formula in Hill-notation fashion -- carbons first, hydrogens second, then the other elements in alphabetical order.

Sources of Information.  Approximately 76.6% of SANSS records include references to one or more sources of further information.  Some 73 different sources of information are currently cited -- 24 CIS databases, 38 print sources, six Internet-accessible sources, and five "other" sources of information.  Naturally, the more common the substance, the more sources of information its record will cite:  Some 28,000 SANSS records cite five or more information sources, and nearly 11,000 records cite 10 or more sources.  (Out of curiosity, we found six substances whose records cited 60 or more sources, and it won't surprise anyone to learn that these most-heavily-documented substances are DDT, Carbon tetrachloride, Ethanol, Chloroform, Benzene, and Trichloroethylene.)

Future updates of SANSS -- another is due in about three months -- will expand the number of SANSS references to Internet-accessible sources of information.  It's the way of the world nowadays, despite the May-fly half-life of a lot of Internet links and the consequent need for constantly battling against link rot.  But we have placed particular emphasis in the latest SANSS update on PRINT sources of information, and that will continue and grow.  It had been our practice, in years gone by, to replace each print source cited with references drawn from later editions as we could incorporate them.  A year or two ago it occurred to us to wonder why we did that -- since, after all, earlier editions of, say, The Merck Index and the Aldrich Catalog were still sitting there on our desk even after they had been joined by later issuances.  Furthermore, even in this Internet age, many institutions still rely heavily on printed sources for basic information gathering.

Consequently, we resolved to build up the print sources cited in SANSS.  As a result, the current version of SANSS cites three different editions of Merck and three different editions of Aldrich -- and the next update will increase the number of Merck editions cited to five and Aldrich editions to four -- and so forth for the foreseeable future. We also plan to re-visit some un-updated citations to print sources from the 1980s, adding references to later editions that are still on the shelves.

We hope users will find this helpful.  Furthermore, if there are print sources that you would particularly like to see referenced in SANSS, please let us know.   We'd be glad to consider any suggestion you send to cissupport@nisc.com.

Consequently, we resolved to build up the print sources cited in SANSS. As a result, the current version of SANSS cites three different editions of Merck and three different editions of Aldrich -- and the next update will increase the number of Merck editions cited to five and Aldrich editions to four -- and so forth for the foreseeable future. We also plan to re-visit some un-updated citations to print sources from the 1980s, adding references to later editions that are still on the shelves.

We hope users will find this helpful. Furthermore, if there are print sources that you would particularly like to see referenced in SANSS, please let us know. We'd be glad to consider any suggestion you send to cissupport@nisc.com.

There are three solutions to this occasional but annoying problem:

• First, exit CIS by using the Logout mechanism at the upper right of the search and results screens. This terminates your session in a way that CIS can recognize.
• Second, change your account to increase the number of allowed concurrent users. This is the option colleges and universities should be thinking about if a large number of students using CIS causes this problem to arise frequently.
• Third, wait eight minutes. The system is set up to close your session and clear your account if there's been no activity in the session in that period of time.

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