lmp1@atsoaa1.em.cdc.gov
http://atsdr1.atsdr.cdc.gov:8080/mikeperry.html
Richard Anderson, Agency for Toxic Substances and Disease Registry, Atlanta, Georgia, USA
rxa5@atsoaa1.em.cdc.gov
http://atsdr1.atsdr.cdc.gov:8080/richardanderson.html
Ronald Parker, Agency for Toxic Substances and Disease Registry, Atlanta, Georgia, USA
rzp1@atsoaa1.em.cdc.gov
ATSDR is directed by law to perform specific functions concerning the effect on public health of hazardous substances in the environment. These functions include public health assessments of waste sites, health consultations concerning specific hazardous substances, health surveillance and registries, response to emergency releases of hazardous substances, applied research in support of public health assessments, information development and dissemination, and education and training concerning hazardous substances.
In pursuit of its mission over the past 8 years, ATSDR has developed HazDat, a database containing information about the release of hazardous substances into the environment and the effects of those substances on human health. In fact, HazDat is the only database known to us that contains this kind of data in one place. As a result, HazDat is of interest to many people, including public health officials, researchers, and the general public. Because ATSDR has a legislative mandate to develop and disseminate information, we placed a very high priority on making HazDat available to the general public. This goal was achieved in 1994 using the combined technologies of the Internet, the World-Wide Web, Web browsers such as Mosaic, and the GSQL interface to relational databases.
In mid-1993, we became aware of the Mosaic [MOSAIC] application developed by the National Center for Supercomputing Applications (NCSA) [NCSA], which was being beta tested by a rapidly growing number of Internet users. Suddenly, the first official version of Mosaic was released, and we were checking the Internet every day to keep up with the rapid developments. Text information was being made available over the World-Wide Web at an incredible rate and in a format that was intuitive to anyone who had ever used a computer. ATSDR disseminates a lot of information as hardcopy text documents, so we began the process of building a server to make this text information available on the Web. The World-Wide Web and Mosaic were such powerful tools, we wondered if it might be possible to make the Internet HazDat database available similar to the way in which WAIS text databases were being made available through Mosaic version 2 - by using Hypertext Markup Language (HTML) forms to accept user input. Apparently, we were not the only ones looking for this kind of functionality.
In February 1994, we found GSQL on the NCSA Web server. GSQL, developed by Jason Ng of the NCSA Software Development Group, was described as "a simple forms interface in Mosaic to SQL databases." We quickly read the GSQL Tutorial [GSQL], which clearly described the procedure for developing an HTML forms interface to a relational database and a few working examples. We found a couple of bugs in our environment which we were able to fix and reported them to Jason Ng. Within 2 weeks we had created three forms for querying our database. Because GSQL converts the data being returned by an SQL database into another HTML form, we were able to convert some of the data being returned by a query into hypertext that could link to a text document or launch another SQL query to the database. This functionality allowed us to build a hypertext "drill-down" scheme into the database queries, enabling the user to get more detailed data and to follow links to related data within the database. The hypertext concept, which makes the World-Wide Web and Mosaic such powerful and intuitive tools, could now be used to guide a user through a relational database as if it was a series of text documents containing just the information requested by the user. In addition, once the response to a query is returned, it may be saved to a local ASCII file and loaded into another application, such as Lotus or Paradox, for further analysis.
Finishing touches were added to the application as we worked on the appearance of the forms and optimized the database for the queries being generated. The data dictionary for Internet HazDat was made available as HTML text documents that can be accessed from many locations within the application. This data dictionary defines all the columns that can be accessed and includes example data from each column. These metadata play an indispensable part in the sharing of any database [WWW94-1]. Also, in what we believe was a first, we included HTML anchors within a Sybase text field to seamlessly link a database record to an external HTML text document. The HTML documents linked to the database are the very popular Public Health Statements - short summary documents taken from the ATSDR Toxicological Profiles that contain information on specific toxic substances often found in and around hazardous waste sites.
http://atsdr1.atsdr.cdc.gov:8080/gsql/siteact.script
http://atsdr1.atsdr.cdc.gov:8080/gsql/sitecontam.script
http://atsdr1.atsdr.cdc.gov:8080/atsdrhome.html
http://www.os.dhhs.gov/
http://atsdr1.atsdr.cdc.gov:8080/hazdat.html
http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/NCSAMosaicHome.html
http://www.ncsa.uiuc.edu/General/NCSAHome.html
http://www.ncsa.uiuc.edu/SDG/People/jason/pub/gsql/starthere.html
http://www.ncsa.uiuc.edu/SDG/IT94/Proceedings/Searching/crossley/paper.html
http://www.ncsa.uiuc.edu/SDG/IT94/Proceedings/EarSci/zimmerman/zimmerman.html
http://www.ncsa.uiuc.edu/SDG/IT94/Proceedings/HCI/register/register.html