Effort launched to link glucocorticoid receptor bioassay to biological impacts in fish

SCCWRP and its partners completed an initial round of lab experiments in March for a study investigating how the glucocorticoid receptor (GR) assay could be used to provide an early-warning indicator that certain classes of bioactive chemical contaminants in aquatic environments are potentially triggering adverse biological impacts in fish.

Researchers’ goal is to understand the relationship, or linkage, between how this type of bioanalytical assay responds to exposure to glucocorticoid chemical contaminants, and how fish respond to exposure to the same contaminant levels. The study will pave the way for developing bioscreening thresholds for the GR assay that are sufficiently protective of fish health.

Previously, SCCWRP and its partners documented a similar linkage between the estrogen receptor assay and adverse biological effects in fish following exposure to estrogen-mimicking chemicals.

Researchers expect that developing such a linkage for glucocorticoids – commonly found in anti-inflammatory steroids – will be more challenging than estrogen-mimicking chemicals, as the biological effects of fish exposed to glucocorticoids are less well-documented than for fish exposed to estrogen-mimicking chemicals.

Researchers are initially tracking linkages between the fish’s glucose metabolism and immune responses.