SETAC Europe 2017
Meet with EAG Laboratories at SETAC Europe 2017, the annual meeting of the Society of Environmental Toxicology and Chemistry, to be held May 7-11, 2017 in Brussels. We will be at Booths #5 and #7, and we are also presenting a technical poster. We look forward to meeting with our clients to discuss:
Contact us to schedule an appointment at SETAC Europe 2017!
EAG scientists will present during four technical programs:
Using a Database of Avian Reproductive Performance to Enhance Evaluation of Agrochemical Product Toxicity
Track and Session 1: Ecotoxicology and human toxicology (from molecules to organisms, from omics to in vivo).
Authors: Diana Temple, David Palmer, Kirsten Hammett, Tim Springer and Jared Ross (EAG Laboratories)
Avian reproduction studies with northern bobwhite (Colinus virginianus) and mallard (Anas platyrhnchos) have been conducted for nearly 40 years. The information collected from these gamebird species has been a primary part of the OECD and EPA regulatory program in evaluating agrichemical products and making environmental risk assessments. Data from these two species have been collected and maintained since the late 1970’s by Wildlife International (now operating as a division of EAG Laboratories). The databases compile values for reproductive parameters measured from birds used in each control group as part of each reproduction study conducted at the lab in Easton, Maryland, USA. The database compiles mean numbers of eggs laid, fertility of the eggs, normal development including viability and survival of the embryos, hatchability, offspring survival, egg shell thickness and weights of offspring and 14-day old survivors. Data collected in these records are becoming more critical in supporting evaluation of reproduction study results.
There is complexity in making meaningful decisions about the toxicity of agrochemical products. When ‘wild type’ birds are used we can expect inherent differences in performance and that occasional anomalies will occur. Rather than repeating multiple tests or increasing the number of birds tested, databases, such as this one, can help risk assessors and regulators make necessary judgements about the validity of differences observed in the range of reproductive parameters evaluated. As the use and power of statistical programs such as CETIS® and TOXRAT® improve our ability to evaluate data and look at trends there is a need to balance these statistical evaluations with the integrity of the scientific processes observed in these toxicology tests. Moving forward a shared database system can be a valuable tool in improving interpretation of study results and evaluating mechanistic and population level effects.
Download the Application Note
The Importance of Weight of Evidence Considerations for Assessment of Potential Endocrine Activity: A Case Study for Carbaryl
Track and session 6: Environmental Policy, Risk Management and Risk Communication: Regulatory Best Practices for Assessment of Endocrine Active Substances
Authors: Duane Huggett (EAG Laboratories, Waterborne Environmental), Matt McCool, Lisa Ortego (Bayer CropScience) and Kevin Henry (NovaSource)
Carbaryl was included in the first list of chemicals to undergo Tier 1 screening in US EPA’s EDSP. Fish short-term reproduction assay (FSTRA) secondary male sex characteristics and gonadal histopathology data were interpreted as being suggestive of potential interaction with the androgen pathway in male fish. An EDSP Tier 2 Medaka Extended One-Generation Reproduction Test was suggested to be potentially useful based on these findings. The purpose of our analysis was to determine if potential endocrine responses in fish as seen in the FSTRA might be secondary to ChE inhibition. An extensive review of the extant literature, standard guideline study reports, and relevant US EPA regulatory documents was conducted.
In male fish, there was an increased incidence of testicular degeneration as percentage of spermatogonia in the highest nominal treatment. There were no histopathological findings in females. There was a slight decrease in the median tubercle score (34 vs. 29 for controls vs. high dose, respectively). However, the remainder of the measurements related to endocrine modulation were negative. In addition, a fish full life cycle (FFLC) study was available in the fathead minnow. The highest nominal dose in this study resulted in marked reduction of F0 survival and F0 reproductive performance, with no reproductive effects seen at doses where impairments of growth and survival were observed.
Multiple studies have measured brain ChE levels in fish following exposure to carbaryl, as well as other carbamate pesticides. For example, two studies with rainbow trout reported statistically significant decreases in brain ChE levels at aqueous carbaryl concentrations ≤ 0.25 mg/L.
Based on previous studies, it can be concluded that carbaryl, at doses identified as levels demonstrating systemic toxicity in two fish reproductive studies, would be expected to inhibit ChE and is likely the primary mechanism driving reproductive and possible endocrine effects. In the FFLC study, concentrations that affected reproductive parameters also reduced survival, and the survival endpoint is thus protective of effects on reproduction, regardless of MoA. However, it can be concluded that the reproductive and endocrine findings in the FSTRA and the FFLC studies are secondary to ChE inhibition and systemic toxicity.
Advances in the Environmental Fate of Down-the-Drain Chemicals, including Pharmaceuticals
Platform session: Environmental Fate
Chairs: Duane Huggett and Ed Schaefer, EAG Laboratories
There is an increased interest in understanding the environmental risk of Down-the-Drain (DtD) chemicals, such as pharmaceuticals and personal care products. Inherent in the environmental risk assessment (ERA) process is the conduct of environmental fate studies, such that a detailed understanding of the compartments of interest, rate kinetics and predicted environmental concentrations can be utilized within the ERA. With such interest in the DtD chemicals, it is not surprising that there has been a considerable amount of scientific advances to better predict the environmental fate of these types of chemicals. This proposed session will highlight the global advances in wastewater/watershed modeling and laboratory environmental fate studies, including the use of appropriate protocols and test conditions to more accurately reflect environmental conditions, leading to a more predictive paradigm for assessing the environmental fate of DtD chemicals. The speakers will not only illustrate the advances in the field, but will draw upon the historical environmental fate methodologies conducted for these DtD chemicals and elucidate why some of the current tests (e.g. ready biodegradation test) may not be useful. Session attendees will come away from this session with a detailed knowledge of the limitations of the current methodologies, as well as the new methodologies to overcome these limitations.
Future Challenges in Sediment Toxicity Testing for Environmental Risk Assessment
Chairs: Henry Krueger (EAG Laboratories) Daniel Faber, Theo Brock and Paul Sibley
Poster: Evaluating the Relative Sensitivity of Endpoints Generated During Midge LifeCycle Sediment Toxicity Tests for US Pesticide Registration, Author: Henry Krueger (EAG Laboratories)