Geology topics

Joanne L. Parrott

Publications and source records attributed to Joanne L. Parrott.

2 recordsLinked to original sources

USGS2017

Recommended approaches to the scientific evaluation of ecotoxicological hazards and risks of endocrine-active substances

A SETAC Pellston Workshop ® “Environmental Hazard and Risk Assessment Approaches for Endocrine-Active Substances (EHRA)” was held in February 2016 in Pensacola, Florida, USA. The primary objective of the workshop was to provide advice, based on current scientific understanding, to regulators and policy makers; the aim being to make considered, informed decisions on whether to select an ecotoxicological hazard- or a risk-based approach for regulating a given endocrine-disrupting substance (EDS) under review. The workshop additionally considered recent developments in the identification of EDS. Case studies were undertaken on 6 endocrine-active substances (EAS—not necessarily proven EDS, but substances known to interact directly with the endocrine system) that are representative of a range of perturbations of the endocrine system and considered to be data rich in relevant information at multiple biological levels of organization for 1 or more ecologically relevant taxa. The substances selected were 17α-ethinylestradiol, perchlorate, propiconazole, 17β-trenbolone, tributyltin, and vinclozolin. The 6 case studies were not comprehensive safety evaluations but provided foundations for clarifying key issues and procedures that should be considered when assessing the ecotoxicological hazards and risks of EAS and EDS. The workshop also highlighted areas of scientific uncertainty, and made specific recommendations for research and methods-development to resolve some of the identified issues. The present paper provides broad guidance for scientists in regulatory authorities, industry, and academia on issues likely to arise during the ecotoxicological hazard and risk assessment of EAS and EDS. The primary conclusion of this paper, and of the SETAC Pellston Workshop on which it is based, is that if data on environmental exposure, effects on sensitive species and life-stages, delayed effects, and effects at low concentrations are robust, initiating environmental risk assessment of EDS is scientifically sound and sufficiently reliable and protective of the environment. In the absence of such data, assessment on the basis of hazard is scientifically justified until such time as relevant new information is available.

Integrated Environmental Assessment and Management↗

USGS1997

The use of semipermeable membrane devices (SPMDs) to concentrate inducers of fish hepatic mixed function oxygenase (MFO): Chapter 12

Semipermeable membrane devices (SPMDs) are sampling and concentrating devices comprised of a thin polyethylene membrane containing a small quantity of triolein. They have previously been used to sample air, water and sediments and have concentrated fish tainting compounds from pulp mill effluents. The ability to induce mixed function oxygenases (MFOs) is a property of a variety of organic effluents, but the compound(s) responsible for induction have not been identified. We wanted to see if SPMDs would accumulate the MFO-inducing chemical(s) from pulp mill effluents and oil refinery effluents. Dialysates of effluent-exposed SPMDs induced ethoxyresorufin-O-deethylase (EROD) activity in a fish ( Poeciliopsis lucida ) hepatoma cell line, PLHC-1. In pulp mill effluents and oil sands mining and refining wastewaters, potencies varied greatly, from a few to thousands of pg TCDD-EQ/g SPMD. Low levels of inducers were seen in four pulp mills on the Athabasca R., and higher levels at one New Brunswick bleached sulphite and two Ontario bleached kraft pulp mills. The highest levels of MFO inducers were in SPMDs deployed for 14 days in wastewater from an oil sands upgrading facility, as well as SPMDs deployed at two sites on Athabasca River tributaries in the oil sands area. This suggests that natural erosion and weathering, as well as industrial processing of the oil sands, can release potent MFO inducers. Background (reference) induction by SPMD extracts ranged from non-detectable (<1) to 20 pg TCDD-EQ/g SPMD. Reactive clean-up of one of the bleached kraft mill effluent-exposed SPMD extracts on a sulfuric acid/silica gel column resulted in loss of the inducer(s), which suggested a polyaromatic hydrocarbon-type of inducing chemical(s), rather than a dioxin or furan inducer. SPMD deployments proved useful in the detection of inducers within the pulp mill process streams as extracts of SPMDs exposed to untreated bleached sulphite effluent were ten to twenty times as potent as those from secondary-treated effluent. Little is known about the nature and identity of the MFO inducers from pulp mill and refinery effluents, but the use of SPMDs as concentrators of MFO-inducing substances appears a promising avenue for future research.

Book chapter↗