title: Overview of the Standing Operating Procedure (SOP) for the development of Provisional Advisory Levels (PALs).
abstract: Provisional Advisory Levels (PALs) are concentrations in air and drinking water for priority toxic chemicals. This article summarizes the Standing Operating Procedure (SOP) currently in place for the data-driven development of chemical-specific PALs. To provide consistency and transparency, and to avoid faults of arbitrariness, the SOP was developed for guidance in deriving PAL values. Three levels (PAL 1, PAL 2, and PAL 3), distinguished by severity of toxic effects, are developed for 24-hour, 30-day, 90-day, and 2-year durations of potential drinking water and inhalation exposures for the general public. The SOP for PAL development focuses on (1) data acquisition and analysis, (2) identification of a chemical-specific critical effect, (3) selection of a quantitative point-of-departure (POD), (4) uncertainty analysis and adjustments, (5) exposure duration adjustment and extrapolation, (6) identification of special concerns and issues, and (7) verification, documentation, and dissemination of PALs. To avoid uncompromising rigidity in deriving PAL values and to allow for incorporation of new or refined methodologies, the overall procedure is fluid and subject to modification. The purpose of this publication is to provide a summary of this SOP.
authors.affiliation: Toxicology and Hazard Assessment Group, Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA. youngra@ornl.gov
authors.forename: Robert A
authors.initials: RA
authors.lastname: Young
authors.forename: Cheryl B
authors.initials: CB
authors.lastname: Bast
authors.forename: Carol S
authors.initials: CS
authors.lastname: Wood
authors.forename: Femi
authors.initials: F
authors.lastname: Adeshina
mesh_terms: D000393:Air Pollutants / Q000009:adverse effects / Q000592:standards*; D000818:Animals; D003253:Consultants; D004781:Environmental Exposure / Q000009:adverse effects / Q000592:standards; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects / Q000592:standards*; D012015:Reference Standards; D014481:United States; D014873:Water Pollutants / Q000009:adverse effects / Q000592:standards*; D014881:Water Supply / Q000592:standards
chemical_list: D000393:Air Pollutants; D014873:Water Pollutants