Indicators of exposure to estrogenic compounds at Great Lakes Areas of Concern: species and site comparisons

Abstract

Adverse effects resulting from potential exposure of wild fishes to estrogenic endocrine disruptors were assessed at seven United States Great Lakes Areas of Concern using biomarkers ranging from organismal (gonadosomatic indices) to tissue/plasma (histology, plasma vitellogenin) and molecular (hepatic gene transcripts) levels. Biomonitoring was conducted on pelagic, top predator species, largemouth Micropterus salmoides and smallmouth M. dolomieu bass and benthic, omnivorous white sucker Catostomus commersonii. Seasonal (spring and fall) comparisons were conducted at select sites. Intersex (testicular oocytes), plasma vitellogenin, and hepatic vitellogenin transcripts were commonly observed in bass species. Testicular oocyte severity was positively, although weakly, correlated with plasma vitellogenin, hepatic transcripts of vitellogenin, estrogen receptor α, and estrogen receptor β2, while negatively correlated with androgen receptor β and phosphoenolpyruvate carboxykinase. No testicular oocytes were observed in white sucker; however, plasma vitellogenin and hepatic vitellogenin transcripts were commonly detected in the males. The results demonstrate the importance of utilizing multiple endpoints to assess exposure to estrogenic compounds as well as the importance of choosing sensitive species.

Reconnaissance of Surface Water Estrogenicity and the Prevalence of Intersex in Smallmouth Bass (Micropterus Dolomieu) Inhabiting New Jersey

“…This may be an informative association, but the temporal window here is limited. A weak positive correlation between intersex severity and plasma vitellogenin has been reported previously in this species [60].…”

Effects of early life stage exposure of largemouth bass to atrazine or a model estrogen (17α-ethinylestradiol)

“…A high prevalence of testicular oocytes, an intersex condition, has been observed in smallmouth bass within the Potomac ( Blazer et al, 2007 , 2010 ; Iwanowicz et al, 2009 ) and Susquehanna ( Blazer et al, 2014 ) river basins of the Chesapeake Bay watershed (CBW) in the eastern United States. Throughout North America, intersex gonads have been found in black bass species including smallmouth bass ( Micropterus dolomieu ) and largemouth bass ( Micropterus salmoides) ( Abdel-Moneim et al, 2015 ; Blazer et al, 2018 ; Grieshaber et al, 2018 ; Hinck et al, 2009 ; Iwanowicz et al, 2016 ; Kellock et al, 2014 ; Yonkos, Friedel & Fisher, 2014 ). The individual chemicals, complex mixtures of chemical compounds and/or other environmental stressors contributing to the development of intersex in specific areas are not yet fully understood.…”

The effects of tissue fixation on sequencing and transcript abundance of nucleic acids from microdissected liver samples of smallmouth bass (Micropterus dolomieu)

“…For endpoint PCR, primers EF1α5F ( ) and EF1α5R ( ) were designed with NCBI Primer BLAST [ 46 ] to amplify a 395 bp amplicon of the smallmouth bass elongation factor 1 alpha ( EF1α ; accession # HQ424872.1) gene. This housekeeping transcript was chosen since it has been used in other smallmouth bass studies [ 17 , 47 ] and sequence data was available for both smallmouth bass and the closely related largemouth bass (accession # KT827794.1). PCR amplification was conducted under the following conditions: denaturation at 95°C for 3 min, followed by 34 cycles of 95°C for 30 s, 60°C for 30 s, and 72°C for 1 min 30 s, with a final extension at 72°C for 5 min.…”

“…More recently, genomic endpoints are also being incorporated into environmental monitoring and risk assessment [ 12 – 14 ]. When both histopathology and molecular analyses are part of an assessment, pieces of a tissue are commonly preserved in 10% buffered formalin or a similar preservative and adjacent, separate pieces are preserved in RNAlater®, 95% ethanol, or frozen for molecular analyses [ 15 – 17 ]. However, for alterations not visible, the tissue piece chosen for gene expression may not contain the same cellular components or alterations as those within the histology section.…”