Individual effects of platinum group elements (palladium and platinum) on rainbow trout olfaction

Abstract

The platinum group elements (PGEs) palladium (Pd) and platinum (Pt) are introduced to aquatic ecosystems through emissions processes from industrial applications. Despite this, little is understood about the toxicity of these metals to aquatic organisms, especially fishes. Considering ambient concentrations of PGEs are relatively low in natural systems, the use of sensitive endpoints such as olfaction is ideal in informing the development of ecological guidelines and risk assessments. We can conclude from the present study that Pd is toxic to rainbow trout olfaction near environmentally relevant concentrations, whereas Pt is not. Through the manipulation of water quality parameters, it is clear water hardness plays a role in olfactory acuity. Further investigation on Pd-induced olfactory toxicity demonstrated bioaccumulation of Pd at the olfactory organ, supporting the bioavailability of waterborne Pd. As PGE contamination continues to increase, understanding ecological impacts remains critical to protect aquatic life from these contaminants of emerging concern.