A5055458022- Reproductive biology and impacts on aquatic species
- Effects and risks of endocrine disrupting chemicals
- Pharmaceutical and Antibiotic Environmental Impacts
- Environmental Toxicology and Ecotoxicology
- Fish Ecology and Management Studies
- Wildlife Ecology and Conservation
- Toxic Organic Pollutants Impact
- Aquaculture Nutrition and Growth
- Amphibian and Reptile Biology
- Chemical Analysis and Environmental Impact
- Animal Behavior and Reproduction
- Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
- Primate Behavior and Ecology
- Sperm and Testicular Function
- Physiological and biochemical adaptations
- Electrochemical sensors and biosensors
- Viral Infectious Diseases and Gene Expression in Insects
- Pesticide Residue Analysis and Safety
- Anesthesia and Neurotoxicity Research
- Evolution and Genetic Dynamics
- Pesticide and Herbicide Environmental Studies
- Marine animal studies overview
- Hormonal and reproductive studies
- Estrogen and related hormone effects
- Reproductive Biology and Fertility
Syngenta (United Kingdom)
2017-2024
Brunel University of London
2005-2015
Environment Agency
2006
Brixham Community Hospital
2002-2005
AstraZeneca (United Kingdom)
2002-2005
University of Manchester
1999-2003
University of Florida
1995-1999
Many environmental contaminants alter the reproduction of animals by altering development and function endocrine system. The ability to system alligators was studied both in a descriptive study which juvenile from historically contaminated lake were compared control an experimental hatchling exposed ovo several endocrine-disrupting standards two modern-use herbicides. Endocrine status assessed examining plasma hormone concentrations, gonadal-adrenal mesonephros (GAM) aromatase activity,...
Abstract A eedi recognizedforthedevelopmentandevaluationofbioassaysfordetectionofthyroid s stem–disrupting compounds. The issue of testing for thyroid disruption can be addressed by exploiting amphibian metamorphosis as a biological model. In the present study, test protocol Xenopus assay (XEMA) was developed and its interlaboratory transferability evaluated in an informal ring with six laboratories participating. XEMA test, exposure laevis tadpoles initiated at stages 48 to 50 continued 28...
Abstract Sex-steroid and thyroid hormones are critical regulators of growth reproduction in all vertebrates, several recent studies suggest that environmental chemicals can alter circulating concentrations these hormones. This study examines plasma estradiol-17β (E2), testosterone (T), triiodothyronine (T3), thyroxine (T4) juvenile alligators (60–140 cm total length) from two contaminated lakes one reference lake Florida. First, the data were analyzed by comparing hormone among males females...
A SETAC Pellston Workshop® "Environmental Hazard and Risk Assessment Approaches for Endocrine-Active Substances (EHRA)" was held in February 2016 Pensacola, Florida, USA. The primary objective of the workshop to provide advice, based on current scientific understanding, regulators policy makers; aim being make considered, informed decisions whether select an ecotoxicological hazard- or a risk-based approach regulating given endocrine-disrupting substance (EDS) under review. additionally...
There is currently little evidence of pollution-induced endocrine dysfunction in amphibia, spite widespread concern over global declines this ecologically diverse group. Data regarding the potential effects endocrine-disrupting contaminants (EDCs) on reproductive function amphibia are particularly lacking. We hypothesized that estrogenic EDCs may disrupt progesterone-induced oocyte maturation adult amphibian ovary, and tested with an vitro germinal vesicle breakdown assay using...
Perchlorate is a known environmental contaminant, largely due to widespread military use as propellant. acts pharmacologically competitive inhibitor of thyroidal iodide uptake in mammals, but the impacts perchlorate contamination aquatic ecosystems and, particular, effects on fish are unclear. Our studies aimed investigate concentrations ammonium that can occur environment (1, 10, and 100 mg/L) development fathead minnows, Pimephales promelas. For these studies, exposures started with...
For ecotoxicological risk assessment, endocrine disruptors require the establishment of an mode action (MoA) with a plausible link to population-relevant adverse effect. Current ecotoxicity test methods incorporate mostly apical endpoints although some also include mechanistic endpoints, subcellular-through-organ level, which can help establish MoA. However, between these and population-level effects is often unclear. The case studies endocrine-active substances (EAS) (tributyltin,...
The importance of thyroid hormones in regulating early developmental processes many amphibian and fish species is well known, but the impacts exposure to disrupters homeostasis during embryo-larval-juvenile transitions are unclear. To investigate these impacts, fathead minnows, Pimephales promelas, were exposed a model axis disrupter, methimazole, an inhibitor hormone synthesis, at control (0), 32, 100, 320 μg/l, starting <24-h postfertilization, for 28, 56, 83/84 days postfertilization...
Thiamethoxam is a widely used neonicotinoid insecticide that has been detected in surface water monitoring programs North America and Europe. This led to questions about its toxicity nontarget insects, specifically those with an aquatic life stage. To address the uncertainty associated possible impacts from environmental exposures, chronic (35-d) outdoor mesocosm study formulated product containing thiamethoxam was conducted. The specific focus of response mayflies (Ephemeroptera), which...
Evidence increasingly suggests that some environmental pollutants are able to permanently affect development of the endocrine system in wildlife. Embryonic and neonatal exposure these endo- crine-disrupting contaminants can cause structural functional abnormalities reproductive system. It has recently been hypothesized demasculinization a population male juvenile American alli- gators (Alligator mississippiensis) from Lake Apopka, Florida, could result antiandrogenic contaminants. The...
Many environmental contaminants alter the reproduction of animals by altering development and function endocrine system. The ability to system alligators was studied both in a descriptive study which juvenile from historically contaminated lake were compared control an experimental hatchling exposed ovo several endocrine-disrupting standards two modern-use herbicides. Endocrine status assessed examining plasma hormone concentrations, gonadal-adrenal mesonephros (GAM) aromatase activity,...
We have developed and validated a computer-assisted sperm-motility assessment (CASA) method for use with the emerging amphibian model Silurana tropicalis. The testicular sperm-activation was by analysing activation replicate coefficients of variation, effects tracking time settings on velocity distributions relative partitioning differentially motile sperm subpopulations between matched right left testes. Two major were identified using multivariate pattern analysis their frequencies...