Effects of the synthetic estrogen 17 alpha-ethinylestradiol on the life-cycle of the fathead minnow (Pimephales promelas).

نویسندگان

  • R Länge
  • T H Hutchinson
  • C P Croudace
  • F Siegmund
  • H Schweinfurth
  • P Hampe
  • G H Panter
  • J P Sumpter
چکیده

A fish full life-cycle (FFLC) study was conducted for 17 alpha-ethinylestradiol (EE2) using the fathead minnow, Pimephales promelas. Newly fertilized embryos (< 24 h old) were exposed to five concentrations of EE2 (0.2, 1.0, 4.0, 16, and 64 ng/L nominal) in continuous flow-through conditions for 305 d at 25 +/- 1 degrees C. Exposure concentrations were verified by 14C-EE2 radiochemistry, supported by radioimmunoassay, and mean measured values were > or = 70% of nominal. For the F0 adult phase until 301 d posthatch, the no-observed-effect concentrations (NOECs) for growth, survival, and reproduction (as egg production) were all > or = 1.0 ng/L. The NOEC values for F1 embryo hatching success and larval survival (at 28 d posthatch) were both > or = 1.0 ng/L. While statistically detectable changes in F1 growth were evident at 0.2 ng/L, these were not considered to be biologically significant when compared with historical control data. Male fish exposed to EE2 at 4.0 ng/L failed to develop normal secondary sexual characteristics; on the other hand, assumed females exposed to this level of EE2 were able to breed when paired with males that had not been exposed to EE2. Histology of F0 control, 0.2-, and 1-ng/L exposed fish at 56 d posthatch indicated an approximate female-to-male (F:M) sex ratio of 50:50 (with no ovatestes observed in the control), while fish exposed to EE2 at 4.0 ng/L for 56 d posthatch had a F:M sex ratio of 84:5 (with ovatestes in 11% of fish). After 172 d posthatch, no testicular tissue was observed in any fish exposed to EE2 at 4.0 ng/L. At the same time point, plasma vitellogenin levels were significantly higher in fish exposed to EE2 at 16 ng/L. A lack of sexual differentiation occurred in males at concentrations > or = 4.0 ng/L. Taking into account these data, the overall no-observed-adverse-effect concentration was considered to be 1.0 ng/L.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Effects of 17alpha-ethinylestradiol in a fathead minnow (Pimephales promelas) gonadal recrudescence assay.

To contribute to the development and evaluation of a practical and cost-effective in vivo testing system for endocrine disruption (specifically environmental estrogens), the effects of 17alpha-ethinylestradiol (EE2) were assessed in a gonadal recrudescence assay with the fathead minnow (Pimephales promelas). Mature male and female fathead minnows were kept first at 15 degrees C on a 8 h light/1...

متن کامل

EFFECTS OF SERTRALINE EXPOSURE ON FATHEAD MINNOW (Pimephales promelas) STEROIDOGENESIS Dennis R. Carty Thesis Prepared for the Degree of MASTER OF SCIENCE UNIVERSITY OF NORTH TEXAS December 2014 Carty, Dennis R. Effects of Sertraline Exposure on Fathead Minnow (Pimephales

متن کامل

Modeling impacts on populations: fathead minnow (Pimephales promelas) exposure to the endocrine disruptor 17beta-trenbolone as a case study.

Evaluation of population-level impacts is critical to credible ecological risk assessments. In this study, a predictive model was developed to translate changes in fecundity of the fathead minnow (Pimephales promelas) in a short-term laboratory toxicity test to alterations in population growth rate. The model uniquely combines a Leslie population projection matrix and the logistic equation. App...

متن کامل

Collapse of a fish population after exposure to a synthetic estrogen.

Municipal wastewaters are a complex mixture containing estrogens and estrogen mimics that are known to affect the reproductive health of wild fishes. Male fishes downstream of some wastewater outfalls produce vitellogenin (VTG) (a protein normally synthesized by females during oocyte maturation) and early-stage eggs in their testes, and this feminization has been attributed to the presence of e...

متن کامل

Evaluation of the aromatase inhibitor fadrozole in a short-term reproduction assay with the fathead minnow (Pimephales promelas).

Cytochrome P450 aromatase (CYP19) is a key enzyme in vertebrate steroidogenesis, catalyzing the conversion of C19 androgens to C18 estrogens such as beta-estradiol (E2). The objective of this study was to assess effects of the CYP19 inhibitor fadrozole on fathead minnow (Pimephales promelas) reproductive endocrinology and physiology in a short-term reproduction assay proposed for identifying sp...

متن کامل

ذخیره در منابع من

ذخیره در منابع من قبلا به منابع من ذحیره شده

{@ msg_add @}


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Environmental toxicology and chemistry

دوره 20 6  شماره 

صفحات  -

تاریخ انتشار 2001