RTECS File

The only reported toxicity data on zinc fluoride in the NIOSH RTECS file is a LD q of 280 mg/kg for subcutaneous adniinistration in frogs. 

The RTECS data base can be searched in a number of ways, including NIOSH number, CAS Registry number, type of animal tested, route of dosage, LD50. LC50, etc. The NIOSH RTECS file is also linked to the SSS so that structure-activity correlation work can be performed. 

It must be understood that these lists are greatly duplicative, and some chemicals appear on all of the various lists mentioned above. Thus a reasonable first step is to concentrate on the data contained in the RTECS files for development of methods for application of SAR techniques to hazard assessment. Such methods can be considered for application to the wider universe of all chemical substances after they have been subjected to verification tests with the RTECS data. 

Table 9 Toxicity Data on Brucine from the RTECS File (STN)...

Since systematic chemical name fragments and molecular formula fragments are also found in the RTECS file, one can use CHEMLINE nomenclatural output to perform a substructure search that is correlated with a biological concept in RTECS. This would obviate the need to carry the chemical identifiers for the forty CHEMLINE records into the RTECS file. 

After accessing the RTECS file (Figure 11), the name fragments common to each name listed in the CHEMLINE search (DIBENZO and DIOXIN) and the formula fragment CL are used to retrieve six records. The RTECS Toxicity Data fields (IX) are then searched for the terms ORAL, RAT and TERATOGENIC and the records containing these terms in the index string are Intersected with Search Statement 1 to retrieve two records (Search Statement 2). 

The command to do this is EXIM, which is short for EXact/IMbed switch. The search shown in Figure 11 reveals that there are 2715 compounds in the NIOSH RTECS file that contain at least this ring pattern. To filter such potentially broad responses further, one can use CIDS keys searches and other such constraints as shown below. 

RTECS Registry of Toxic Effects of Chemical Substances number is a unique and unchanging number used to cross-reference the RTECS database, which is a compendium of data extracted from the open scientific literature. Six types of toxicity data are included in each file (1) primary irritation, (2) mutagenic effects, (3) reproductive effects, (4) tumorigenic effects, (5) acute toxicity, and (6) other multiple dose toxicity. 

NIOSH. 1984. Current awareness file. Registry of Toxic Effects of Chemical Substanees (RTECS). Cincinnati, OH U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health. 

In other cases, the Information comes from another Government Agency which retains responsibility for the file, its contents and its maintenance. An example of such a file is the NIOSH RTECS. 

The annual printing of the complete file of the RTECS became impractical due to the rapid growth of the data base and the resultant bulk of the book edition. For this reason a 1983 Supplement to the 1981-82 Printed Edition was published in place of the complete Registry. This supplement contains 18,893 entries (and 93.263 synonyms) and the complete Registry (as of January 1984) lists 66,957 substances and 180,638 synonyms. Since approximately 6,000 new substance entries are made each year, the printed edition of the Registry becomes rapidly outdated. 

In 1981 a new list with 86 additional substances became available (ref. 8). The computer search of the RTECS was reasonably straightforward at that time. The key word "teratogen" was used and the RTECS data base searched for the names of compounds under this classification. The size of the printed file was reasonable (500-600 entries). A copy of the file could be posted in the laboratory, with a short explanation that the list of teratogens should be viewed with caution due to the fact that data from the RTECS are unevaluated and that uncertainties exist about animal-human extrapolations. Any librarian having access to NLM-MEDLARS (National Library of Medicine-... 

RTECS (Registry of Toxic Effects of Chemical Substances). National Institute for Occupational Safety and Health, onhne file retrieved December, 1995. 

RTECS Also available on microfiche and in book form (Registry of Toxic Effects of Chemical Substances List) is an annual compilation of unvalidated toxicity data prepared by the National Institute for Occupational Safety and Health (NIOSH). There is no back file. RTECS contains toxicity data for approximately 40,000 substances. Threshold limit values. 

These data-sets were extracted from the CD-ROM version of RTECS by specifjdng the retrieval of those records that had one of the particular t3q>es of data listed above. Records having WLNs were then extracted from these downloaded files the WLNs were converted to connection tables and these tables were then used to generate fragment screen records for each of the structures. Specifically,... 

FILE MEDLINE FILE MSDS-CCOHS FILE RTECS... 

LC STN Files ANABSTR. BEILSTEIN. BIOBUSINESS, BIOSIS, CA, CAOLD, CAPREVIEWS, CASREACT, CHEMINFORMRX, CHEMLIST, CBNB, CIN, CJACS, CSCHEM, DETHERM, EMBASE, GMELIN, HODOC, IFICDB, IFIPAT, IFIUDB, MEDLINE, NAPRALERT, PNI, RTECS, SPECINFO ( File contains numerically searchable property data)... 

The National Library of Medicine s (NIH) on-line chemical dictionary file (CHEMLINE) is primarily used to enhance the retrieval of bibliographic Information associated with chemical substances. This discussion demonstrates the utility of CHEMLINE as a mechanism to link chemical substructures to biological data. Search techniques are developed to Integrate classes of structurally related chemicals with toxicity data and information contained in on-line retrieval files such as the Registry of Toxic Effects of Chemical Substances (RTECS) and TOXLINE. 

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