Before You Use the GLI Clearinghouse
Querying the Clearinghouse
First, download and install the GLI Clearinghouse. (It's a Microsoft Access database.)
You will be able to select a designated use and chemical of interest. The designated use options are Aquatic Life, Human Health and Wildlife. You can then select by agency or all agencies (if more than one is represented in the database). You can preview the results and download the information of interest.
Data are available only to the extent that they were included in the Agency fact sheets or similar support documents (termed "Original Source" documents), so the number of data fields will vary depending on the criterion and agency. In addition, for certain chemicals having an extensive body of toxicity data, you may have to follow a link to the "Original Source" to view the actual data.
What Information is in the Clearinghouse?
The Clearinghouse includes numeric criteria, data used in calculating criteria, and PDF versions of Agency criteria fact sheets or similar criteria support documents. Data entered in the database is available for download in spreadsheet format. This may be useful if there is a need to compare results and their inputs and in the generation of new criteria. The fact sheets are equally important in that they provide methodology information on how agencies derived a criterion and details on the toxicity and exposure data that could not be captured in the spreadsheets. Users should consider the downloadable spreadsheets and the fact sheets as companion documents in using the Clearinghouse.
The information in the database consists of criteria values, and additional information pertinent to the criteria. Under Aquatic Life designated uses, the database includes the toxicity data that were used to derive the criteria. Under Human Health and Wildlife designated uses, the database includes exposure parameters that were used to derive the criteria. Human Health and Wildlife fact sheets usually did not include toxicity data, per se, instead referencing EPA's Integrated Risk Information System (IRIS). When data is presented, the Human Health toxicity information is in a narrative format that could not be easily reduced for a numeric database.
Interpreting Query Results
Search results are presented separately according to the type of criterion. Types of criteria are broken down within each designated use:
- Aquatic life consists of acute and chronic criteria.
- Human health includes criteria that protect for carcinogenic and noncarcinogenic effects within the context of fish consumption (e.g., non-drinking water supply), water consumption (e.g., public drinking water supply), and fish-and-water consumption (e.g., public drinking water supply).
- Wildlife criteria protect for consumption of both fish and water.
The Data Fields List contains the complete list of fields for which data could be entered.
Keep in mind that the Clearinghouse is not the official source for criteria, or the supporting toxicity data and exposure information. Official sources include state, tribal and federal water quality standards regulations, guidance, and other support documents (including agency fact sheets) as appropriate. If there are any questions regarding specific data used by an agency in calculating criteria, please contact the agency directly (see GLI State and Tribal Contacts).