Estrogenicity of river water is highly variable and it is difficult to obtain an average measure of the estrogenicity. Consequently it is difficult to tie the estrogenic effects observed in fish to their level of exposure to estrogens . To get a better handle on average estrogenic exposure we tested a recently developed passive sampling system (polar organic chemical integrative sampler, POCIS). In addition, we investigated the bioaccumulation of estrogens in caged brown trout and measured plasma vitellogenin in males as a bioindicator of estrogenic effects.We developed a mini-caging method to suit the hydrological conditions in small rivers and to improve upon the often poor survival of salmonids in caging trials. POCISs were positioned upstream and downstream of 5 sewage treatment works' discharges and left on site for 3 weeks (as were the caged fish ), during which period 3 water grab samples were taken at each site. Concentrations of estrogens were determined using a yeast-based reporter gene assay and chemical analysis . Results from grab sampling , passive sampling , and bioaccumulation were correlated; however, plasma vitellogenin concentrations were elevated at only I of 5 sites. POCISs provide an integrated and biologically meaningful measure of estrogenicity in that they accumulate estrogens in a pattern similar to that of brown trout. Minicaging appears a significant methodological advance; no fish were lost, moreover, all fish survived in excellent health.
from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2kWyuHW
via IFTTT
Εγγραφή σε:
Σχόλια ανάρτησης (Atom)
Δημοφιλείς αναρτήσεις
-
Pulmonary complications post hematopoietic stem cell transplant in dyskeratosis congenita: analysis of oxidative stress in lung fibrobl...
-
Background. Antitumor necrosis factor (anti-TNF) therapy is a highly effective but costly treatment for inflammatory bowel disease (IBD). Me...
-
Abstract Desmoplastic small round cell tumor (DSCRT) is a rare malignancy most often seen in the abdomen or pelvis of young men. Unfortuna...
-
from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2nGQ2DC via IFTTT
-
Article content meets expectations Minimal relevance to assigned subject matter. Article content fails to meet all requirements Not Rubric f...
-
Objective To determine the association between neuroendocrine tumor (NET) biomarker levels and the extent of disease as assessed by 68 Ga DO...
-
Elementary school kids, on the other hand, can read, write, reason and think highly complex thoughts. Adele Faber and Elaine Mazlish, author...
-
by Mindaugas Paužuolis, Torsten Eich, Joachim Burman Background Natalizumab (NTZ) is a drug that has been widely used in the treatment of m...
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου