View source for Effects of methoprene, nonylphenol and estrone on the vitellogenin production of opossum shrimp

[[Image:Neomysis integer.jpg|thumb|left|250px| <div style="text-align: center;">
Opossum shrimp © John Rundle (MARLIN)</div>]]
<u>'''Context of the study'''</u><P>
A number of [[anthropogenic]] chemicals are known to have the potential to disrupt the [[Vitellogenins|vitellogenin]] production in vertebrates. Male fish e.g. are known to produce this protein when exposed to xeno-estrogens [[Effects of xenoestrogens in eels|(case study in eels)]].Little is know however about the potential effects of such [[endocrine disrupting compounds]] on the vitellin production of invertebrates<ref name=ha>[http://www.vliz.be/imis/imis.php?module=ref&refid=97941 Ghekiere, A.; Verslycke, T.; Janssen, C.R. (2006). Effects of methoprene, nonylphenol, and estrone on the vitellogenesis of the mysid Neomysis integer. Gen. Comp. Endocrinol. 147(2): 190-195] </ref>. 
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<u>'''Content of the study'''</u><P>
Within the framework of the [http://www.vliz.be/projects/endis/ ENDIS-RISK project] a high exposure of the Scheldt estuary [http://www.marinespecies.org/aphia.php?p=taxdetails&id=120136 opossum shrimp] population to endocrine disrupting substances has been detected, including several [[OSPAR_List_of_priority_substances|priority substances]].
This study investigated the effects of 3 substances, known to disrupt the endocrine system of fishes, on the vitellogenin production of opossum shrimp. These substances were [[methoprene]], [[nonylphenol]] and estrone. Estrone is a natural female sex hormone (an estrogen), which occurs in the Scheldt estuary at concentrations up to 8ng/l.
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<u>'''Results of the study'''</u><P>
Lethal concentrations for nonylphenol, methoprene and estrone were found to be 590ug/l, 320µg/l and above 10mg/l respectively. Concentrations above 0.01 µg/l and 1 µg/l of methoprene and estrone respectively resulted in a reduction of the vitellogenin content of female opossum shrimp. Concentrations of 0.01 µg/l nonylfenol did show a significant increase in the femal vitellogenin content, while the vitellogenin content of females exposed to higher concentrations of nonylfenol, 1 µg/l and 100 µg/l, didn't increase.
The measured effect concentrations for nonylphenol and methoprene are above the environmental levels in the Scheldt estuary and might therefore pose problems for these and other [http://www.marinespecies.org/aphia.php?p=taxdetails&id=1066 crustaceans]. These concentrations however are higher than those which cause problems for egg laying marine vertebrates (such as fishes)<ref name=ha>[http://www.vliz.be/imis/imis.php?module=ref&refid=97941 Ghekiere, A.; Verslycke, T.; Janssen, C.R. (2006). Effects of methoprene, nonylphenol, and estrone on the vitellogenesis of the mysid Neomysis integer. Gen. Comp. Endocrinol. 147(2): 190-195] </ref>.

==References==
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[[Category:Ecotoxicology]]
[[Category:Coastal and marine pollution]]