Noble Crayfish Are More Sensitive to Terbuthylazine than Parthenogenetic Marbled Crayfish

Abstract

We investigated the sensitivity of two freshwater crayfish species (Astacus astacus and Procambarus virginalis) during embryonic development to chronic exposure to the herbicide terbuthylazine under laboratory conditions. The assessed parameters included time of embryonic development, survival rate, hatching weight and histopathology of hepatopancreas. LC50 (median lethal concentration) and ED50 (median effective concentration) were estimated. We were able to determine effects of terbuthylazine for every investigated parameter. For noble crayfish, the LC50 value after 45 days was 0.11 mg/L, and the histology of the hepatopancreas showed effects starting from 0.025 mg/L. Other parameters revealed effects starting at concentrations of 1.6 mg/L for weight and 6.4 mg /L for embryonic development time and hatching rate. Marbled crayfish only showed effects concerning the hatching rate and survival rate at concentrations without a clear dose-effects curve. As a conclusion, our data shows the risk of terbuthylazine in existing concentrations in freshwater ecosystems to non-target organisms and also the need of toxicological studies on directly affected species in addition to the use of model organisms.

Environmentally relevant atrazine exposure leads to increases in DNA damage and changes in morphology in the hepatopancreas of crayfish (Faxonius virilis)

“…The examination of the hepatopancreas included measuring the number of vacuoles per lobule from ten representative lobules per crayfish or 30 lobules per concentration. Vacuoles that coalesced into one larger vacuole were counted as one vacuole ( Xiao et al 2014 ; Laurenz et al 2020 ). Vacuoles were counted using Cell-Counter, a Fiji plugin ( https://imagej.nih.gov/ij/ ).…”

“…Following exposure to xenobiotics, the hepatopancreas bioaccumulates and stores them in intracellular vacuoles ( Icely and Nott, 1992 ). Changes in the histological organization of the crayfish hepatopancreas may be used as a bio-indicator of contamination ( Popescu-Marinescu et al, 1997 ; Desouky et al, 2013 ; Koutnik et al, 2014 ; Stara et al, 2016 ; Belanger et al, 2017b ; Stara et al, 2018 ; Laurenz et al, 2020 ). The hepatopancreas is formed by numerous tubules separated by connective tissues with four types of epithelial cells, including blister-like secretory cells (B cell) which form large vacuoles that channel off harmful substances ( Abd El-Atti et al, 2019 ).…”

Environmentally Relevant Atrazine Exposure Leads to Increases in DNA Damage and Changes in Morphology in the Hepatopancreas of Crayfish (Faxonius Virilis)

“…Following exposure to xenobiotics, the hepatopancreas bioaccumulates by storing them in intracellular vacuoles (Icely and Nott, 1992). Changes in the histological organization of the cray sh hepatopancreas may be used as a bioindicator of contamination (Popescu-Marinescu et al, 1997; Desouky et al, 2013;Koutnik et al, 2014;Stara et al, 2016;Belanger et al, 2017b;Stara et al, 2018;Laurenz et al, 2020). The hepatopancreas is formed by numerous tubules separated by connective tissues with four types of epithelial cells, including blister-like secretory cells (B cell) which form large vacuoles that channel off harmful substances (Abd El-Atti et al, 2019).…”