title: Uptake and elimination, and effect of estrogen-like contaminants in estuarine copepods: an experimental study.
abstract: OBJECTIVE
  In recent years, anthropogenic chemicals which can disrupt the hormonal systems of both humans and wildlife have been raised to a major cause of concern. The aim of the present work was to determine the bioconcentration factors of the two major alkylphenols (AP) of the Seine Estuary [4-nonylphenol (4 NP) and nonylphenol acetic acid (NP1EC)] and of the synthetic estrogen, estrogen ethinylestradiol (EE2), in Eurytemora affinis after exposure in a continuous flow-through system under environmental realistic conditions. Moreover, the elimination of these compounds in copepods from the Seine Estuary has been investigated by measuring concentrations after 1 week in clean water in comparison to background levels.
  
  
  METHODS
  In this study, the dominant copepod species of the Seine Estuary, E. affinis, was exposed at environmental relevant concentrations under laboratory-controlled conditions to selected waterborn contaminants, a mixture of 4 NP/NP1EC, and a synthetic EE2. The uptake and the elimination of these contaminants by E. affinis have been studied.
  
  
  RESULTS
  The results show that, at the end of the uptake period, both 4 NP and NP1EC, and also EE2 were accumulated in exposed copepods with respective concentration factors of 324, 3,020, and 5,383. A rapid elimination of these compounds was also observed in copepods placed in clean water since 54% of total NP1EC and 100% of EE2 amounts have been lost after 3 days. Pregnenolone was synthesized after exposure to EE2 and AP mixture.
  
  
  CONCLUSIONS
  These results demonstrate that E. affinis has the potency to accumulate but also to eliminate endocrine disrupters which suggests a non-negligible role of this copepod species in the biogeochemical cycles of these contaminants in estuarine ecosystems. Hence, these results also suggest that a transfer of 4 NP, NP1EC, and EE2 to copepod predators and subsequently that secondary poisoning of these organisms might be possible. Estrogen-like contaminants can induce pregnenolone synthesis and affect the reproduction of E. affinis.
  
  
  CONCLUSIONS
  These results suggest the important role of this copepod species in biogeochemical cycles of non-ionic surfactants as well as synthetic steroids in estuarine ecosystems.
  
  
  CONCLUSIONS
  E. affinis could be a non-negligible route of exposure for juvenile fish and underline the potential for deleterious effects on copepod predators.
authors.affiliation: University of Bordeaux 1, CNRS, ISM-LPTC-UMR 5255, 351 cours de la Libération, 33405, Talence, France.
authors.forename: Kevin
authors.initials: K
authors.lastname: Cailleaud
authors.forename: Hélène
authors.initials: H
authors.lastname: Budzinski
authors.forename: Sophie
authors.initials: S
authors.lastname: Lardy
authors.forename: Sylvie
authors.initials: S
authors.lastname: Augagneur
authors.forename: Sabria
authors.initials: S
authors.lastname: Barka
authors.forename: Sami
authors.initials: S
authors.lastname: Souissi
authors.forename: Joëlle
authors.initials: J
authors.lastname: Forget-Leray
mesh_terms: D000818:Animals; D033342:Copepoda / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D052244:Endocrine Disruptors / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics* / Q000494:pharmacology; D004967:Estrogens / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D004997:Ethinyl Estradiol / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics* / Q000494:pharmacology; D005026:Ethylene Glycols / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics* / Q000494:pharmacology; D005602:France; D008401:Gas Chromatography-Mass Spectrometry; D010636:Phenols / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics* / Q000494:pharmacology; D011284:Pregnenolone / Q000032:analysis / Q000737:chemistry; D045483:Rivers; D013997:Time Factors; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics* / Q000494:pharmacology; D014877:Water Pollution, Chemical
chemical_list: D052244:Endocrine Disruptors; D004967:Estrogens; D005026:Ethylene Glycols; D010636:Phenols; D014874:Water Pollutants, Chemical; D014867:Water; C021754:terics; D004997:Ethinyl Estradiol; D011284:Pregnenolone; C041594:4-nonylphenol