You are here:
CONSOLIDATED HUMAN ACTIVITY DATABASE (CHAD) WEBSITE
Citation:
Description:
The Consolidated Human Activity Database (CHAD) has been developed by ManTech Environmental for the Environmental Protection Agency's National Exposure Research Laboratory (NERL). This database was created to support exposure/intake dose/risk assessments. The overall design incorporates comments received from potential users knowledgeable about human activity pattern research and risk assessment. CHAD is a relational database with a graphical user interface that facilitates queries and report generation (available in a PC version only). It contains data from previously existing human activity pattern studies, which were incorporated in two forms: (1) as the original raw data (available in PC version only) and (2) as data modified according to predefined format requirements. The latter involved development of a common activity/location code system, compilation of background questionnaire information, and the application of data quality flags. To enhance CHAD's applicability to assessing intake dose, or uptake rate, associated with exposure to xenobiotic substances, activity-specific metabolic ratios have been added to each activity undertaken by the respondents. CHAD contains data obtained from pre-existing human activity studies that were collected at city, state, and national levels. The purpose of CHAD is to "provide a basis for conducting multi-route, multi-media exposure/intake dose/risk assessments". The database was developed in two segments. Segment 1 was begun in May 1997 and focused on initial scoping efforts, comparisons of acquired target databases, development of a code system, and creation of data quality flags. Segment 2 tasks were started in June 1997 and concentrated on platform selection, creation of the database structure, conflation of the target databases into CHAD format, application of data quality flags, incorporation of the CHAD-formatted data and the original source data (along with pre-existing flags) into the database, resolution of data quality flags, identification of future variables to be added, and further scoping efforts.