Juvenile rainbow darters (Etheostoma caeruleum) were exposed to nominal concentrations of 20 to 1,000 ng/L of 17alpha-ethynylestradiol (EE2) at 120 d posthatch and in a subsequent experiment to 200 ng/L of EE2 with 2.0 to 20,000 ng/L of tamoxifen (TMX) at 150 d posthatch to determine the threshold of estrogen-induced morphological and histological changes in a sexually dimorphic benthic fish sp...

Residues of illegally used hormones are regularly detected in animal products, feed, or cocktails recovered at farms. In order to better understand the effects of dietary exposure to ethinyl estradiol (EE2, 0.03-1 microg/kg body weight [bw]) and zearalenone (ZEA, 0.03-1 mg/kg bw), an immature rat uterotrophic assay was performed and effects were studied at morphological, histological, and gene ...

Fungal, ligninolytic enzymes have attracted a great attention for their bioremediation capabilities. A deficient knowledge of regulation of enzyme production, however, hinders the use of ligninolytic fungi in bioremediation applications. In this work, a transcriptional analyses of laccase and manganese peroxidase (MnP) production by two white rots was combined with determination of pI of the en...

Steroid hormones can act as potent endocrine disruptors when released into the environment. The main sources of these chemicals are thought to be wastewater treatment plant discharges and waste from animal feeding operations. While these compounds have frequently been found in wastewater effluents, few studies have investigated biosolids or manure, which are routinely land applied, as potential...

Many chemicals released into the environment display estrogenic activity including the oral contraceptive ethinyl estradiol (EE2) and the plastic monomer bisphenol A (BPA). EE2 is present in some aquatic systems at concentrations sufficient to alter reproductive function of fishes. Many concerns have been raised about the potential effects of BPA. The National Toxicology Program rated the poten...

The influence of development and ethinylestradiol on low density lipoprotein (LDL)-receptor mRNA and hepatic triglyceride lipase (HTGL) activity and mRNA levels was studied in rat liver and intestine. Intestinal LDL-receptor mRNA levels are maximal in the perinatal period, whereas liver LDL-receptor and HTGL mRNA levels are highest after weaning in adult life. All mRNA levels reach a maximum be...

In aquatic environments, endocrine disrupting chemicals (EDCs) that interfere with the reproductive physiology of males form a threat to the reproduction of populations. This is often manifested as decreased sexual performance or sterility among males. We show that exposure to EDCs can directly affect the mating system of a marine fish, the sand goby (Pomatoschistus minutus). We exposed males f...

Steroidal estrogens, originating principally from human excretion, are likely to play a major role in causing widespread endocrine disruption in wild populations of the roach (Rutilus rutilus), a common cyprinid fish, in rivers contaminated by treated sewage effluents. Given the extent of this problem, risk assessment models are needed to predict the location and severity of endocrine disruptio...