Vitamin A (retinoids) and E (tocopherol) have received increasing attention as possible indicators of exposure to a variety of environmental pollutants. This study examines vitamin A and E indices in fish collected from northern Alberta rivers, where fish are exposed to a variety of industrial effluents, as part of a multi-faceted study into altered fish physiological function due to environmental contaminants. The fish species targeted for collection were burbot, northern pike, and longnose sucker. The investigators conducted biochemical analyses in the laboratory to determine levels of retinol, dehydroretinol, retinyl palmitate (three storage forms of vitamin A), beta carotene (precursor form of vitamin A), and tocopherol in fish livers. For comparison, results are organised into reference (upstream locations and tributaries receiving no input from pulp mills), near-field (within 100 kilometres downstream from a pulp mill source), and far-field (over 100 kilometres downstream) groups, where sample sizes were adequate.