Adverse metabolic effects in fish exposed to contaminants of emerging concern in the field and laboratory

Abstract

Several metabolic parameters were assessed in juvenile Chinook salmon (Oncorhynchus tshawytscha) and staghorn sculpin (Leptocottus armatus) residing in two estuaries receiving wastewater treatment effluent and one reference estuary. We also conducted a laboratory study with fish dosed for 32 days with 16 of the most common contaminants of emerging concern (CECs) detected in feral fish. Several blood chemistry parameters and other indicators of health were measured in fish from the field and laboratory study that were used to assess potential metabolic disruption. The blood chemistry values observed in feral juvenile Chinook salmon were relatively consistent among fish collected from effluent-impacted sites and substantially different compared to reference site fish. These responses were more pronounced in Chinook salmon, which is supported by the disparity in accumulated CECs. The blood chemistry results for juvenile Chinook salmon collected at effluent-impacted sites exhibited a pattern generally consistent with starvation because of similarities to observations from studies of food-deprived fish; however, this response is not consistent with physical starvation but may be contaminant induced. The altered blood chemistry parameters are useful as an early indicator of metabolic stress, even though organismal characteristics (lipid content and condition factor) were not different among sites indicating an early response. Evidence of metabolic disruption was also observed in juvenile Chinook salmon that were exposed in the laboratory to a limited mixture of CECs; however, the plasma parameters were qualitatively different possibly due to exposure route, season, or the suite of CECs. Growth was impaired in the high-dose fish during the dosing phase and the low- and medium-dose fish assayed after 2 weeks of depuration. Overall, these results are consistent with metabolic disruption for fish exposed to CECs, which may result in early mortality or an impaired ability to compete for limited resources.

Emerging contaminants affect the microbiome of water systems—strategies for their mitigation

“…Brodin et al 32 described changes in the behavior of European perch (increased activitynumber of swimming bouts for 10 min; increased boldness-the inverse of latency to enter a novel area during the total trial time; reduce sociality-cumulative time (in seconds) spent close to a group of co-specifics and reduced feeding rate) after exposure to oxazepan. Many other works have described the effects of ECs at trace concentrations in animal behavior [33][34][35] . ECs are also known to alter microbial communities and function, and may be responsible for spreading antibiotic resistance 36,37 .…”

A Call for Collaboration among Water Quality and Fisheries Professionals

“…For example, a whole inland lake study of the synthetic estrogen 17α-ethynyloestradiol in Ontario, Canada, determined that small-bodied fishes were most affected, and that indirect effects cascaded through the aquatic food web affecting the top predator (Lake Trout Salvelinus namaycush), as well as zooplankton (Kidd et al 2014). The long list of pharmaceutical effects on fishes includes changes in time spent swimming versus in refuge (Brandao et al 2013), embryonic development (Schubert et al 2014), gene expression (Gunnarsson et al 2009;Jeffries et al 2015), and feeding (Brodin et al 2013;Hedgespeth et al 2014), as well as metabolic disruption (Meador et al 2018), reproductive failure (Nash et al 2004), population collapse (Kidd et al 2007), and change in assemblage structure (Sanchez et al 2011).…”

Fisheries Volume 45 Number 3 March 2020

“…For example, a whole inland lake study of the synthetic estrogen 17α-ethynyloestradiol in Ontario, Canada, determined that small-bodied fi shes were most aff ected, and that indirect eff ects cascaded through the aquatic food web aff ecting the top predator (Lake Trout Salvelinus namaycush ), as well as zooplankton (Kidd et al 2014 ). The long list of pharmaceutical eff ects on fi shes includes changes in time spent swimming versus in refuge (Brandao et al 2013 ), embryonic development (Schubert et al 2014 ), gene expression (Gunnarsson et al 2009 ;Jeff ries et al 2015 ), and feeding (Brodin et al 2013 ;Hedgespeth et al 2014 ), as well as metabolic disruption (Meador et al 2018 ), reproductive failure (Nash et al 2004 ), population collapse (Kidd et al 2007 ), and change in assemblage structure (Sanchez et al 2011 ).…”