Toxmap.

As more information makes its way into the popular media on the potentially toxic chemicals that are released into the nation's soil, water, and air, consumers want to find out how news reports and feature stories about chemical releases relate to their own neighborhoods and workplaces. Now they have a new tool to help them understand the data: the National Library of Medicine (NLM) TOXMAP pilot program, located online at http://toxmap.aquilent. com/toxmap/index.jsp.

TOXMAP uses geographic information system (GIS) technology to allow users to build maps that show in as much detail as desired the toxic chemicals released in a specific area. One primary source of the data used to create the maps is the U.S. Environmental Protection Agency's annual Toxics Release Inventory (TRI), which at last count included information on nearly 650 chemical released b44y industrial facilities around the nation. TOXMAP also draws data from Data Bank and TOXLINE bibliographic database.

One of the site's newest features is Tour TOXMAP, which provides a guided overview of the site and the tools it has to offer. This section of the website also seeks to inform the NLM's plans for improving the site--for example, by asking questions about whether users would find specific types of presentations helpful--and lets users provide feedback on their visit to the site.

Getting Started With TOXMAP provides a more detailed guide to navigating the site and describes the various types of maps that users can create: releases of a single chemical within a single year; releases of a single chemical over a range of years; customized application of a combination of TRI criteria; and all facilities that have reported releases of any type. This page also elaborates on the specific steps for creating customized maps.

The mapping actually begins with a press of the Start TOXMAP button on the homepage. Searching by chemical name results in releases identified by volume released. A list of links to the side of the map takes users to information including human health effects, manufacturing statistics and uses, environmental fate, and pertinent public health statements. Users can also choose to identify facilities on the map by name. This produces a list of pop-up records of all the chemical releases reported by that facility. Release maps can then be overlaid with selected demographic characteristics (which have been extracted from the 1990 U.S. Census) to a county-level resolution.

Finally, the homepage offers detailed information, through About The Beta, about the statistical and technological inputs that TOXMAP is based on. The beta program has been designed to help TOXMAP developers learn about how and whether the availability of GIS capabilities helps users make better use of the data. Users are invited to critique the site as well as participate in a more formal feedback group.