Bioconcentration and depuration of 14C‐labeled 17‐α‐ethinyl estradiol and 4‐nonylphenol in individual organs of the marine bivalve, Mytilus edulis L.
Endocrine Disrupting Compounds (EDCs), including 17‐α‐ethinyl estradiol (EE2) and 4‐nonylphenol (4‐NP), enter coastal environments primarily in effluents of wastewater treatment facilities, and have become ubiquitous in marine surface waters, sediments and biota. Although EE2 and 4‐NP have been detected in marine shellfish, the kinetics of bioconcentration and their tissue distribution have not been thoroughly investigated. We performed bioconcentration and depuration experiments in the blue mussel, Mytilus edulis, with 3.37 nM EE2 (= 0.999 µg/L) and 454 nM 4‐NP (= 100.138 µg/L). Mussels and seawater were sampled throughout a 38 d exposure and a 35 d depuration period, and six tissues were individually assayed. Uptake of EE2 and 4‐NP was curvilinear throughout exposure and followed a similar uptake pattern: digestive gland > gill ≥ remaining viscera > gonad > adductor > plasma. Depuration, however, varied, with half‐lives ranging from 2.7 d (plasma) to 92 d (gill) for EE2 and 15 d (plasma) to 57 d (gill) for 4‐NP. An innovative modeling approach, with three coupled mathematical models, was developed to differentiate the unique roles of the gill and plasma in distributing the EDCs to internal tissues. Plasma appears pivotal in regulating EDC uptake and depuration within the whole mussel. This article is protected by copyright. All rights reserved