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11:01
Preparation and In Vivo Use of an Activity-based Probe for N-acylethanolamine Acid Amidase
Published on: November 23, 2016
Provisional Advisory Levels (PALs) for acrylonitrile
Susan Goldhaber1, David Dorman, Donald Gardner
1Toxicology and Hazard Assessment Group, Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
Inhalation Toxicology
|October 16, 2009
Summary
Provisional Advisory Levels (PALs) for acrylonitrile exposure were established for drinking water and inhalation. These health-based guidance values address varying exposure durations and toxicological severity.
Area of Science:
- Environmental Health Risk Assessment
- Toxicology
- Public Health
Background:
- Acrylonitrile is a chemical with potential exposure risks through drinking water and inhalation.
- Provisional Advisory Levels (PALs) are health-based guidance values used to assess chemical safety.
- Previous research established methodologies for deriving PALs, detailed in accompanying publications.
Purpose of the Study:
- To apply Provisional Advisory Level (PAL) protocols to acrylonitrile.
- To establish health-based guidance values for various exposure durations and routes.
- To inform public health decisions regarding acrylonitrile exposure.
Main Methods:
- Utilized experimental data, primarily from animal studies, for acrylonitrile toxicity.
- Developed three levels of PALs (PAL 1, PAL 2, PAL 3) reflecting increasing toxic effect severity.
- Calculated PALs for 24-hour, 30-day, 90-day, and 2-year exposure durations via oral and inhalation routes.
Main Results:
- Established oral PALs for 24-hour, 30-day/90-day, and 2-year exposures, with specific values for PAL 1, 2, and 3.
- Established inhalation PALs for 24-hour, 30-day/90-day, and 2-year exposures, with specific values for PAL 1 and 2.
- Noted insufficient data to recommend PAL 3 values for 30-day, 90-day, and 2-year inhalation exposures.
Conclusions:
- PALs for acrylonitrile were successfully derived for various exposure scenarios.
- The established PALs provide crucial guidance for assessing potential health risks from acrylonitrile.
- Data limitations were identified for specific long-term inhalation exposure scenarios.
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