Ecological Risk Assessment for Chlorpyrifos in Terrestrial and Aquatic Systems in the United States

Salinity is a major problem in many regions of Australia, and is predicted to get considerably worse over the next 30–50 years. Most effort has focused on the terrestrial environment, and specifically on the loss of productive agricultural land. Increased salinity can also result in unwanted changes to aquatic ecosystems in rivers, streams and particularly wetlands.This paper first reviews the importance of assessing risks from salinity increases in a catchment context, and then introduces a disturbance–response conceptual model to assist with the understanding of such situations. Two factors are shown to be particularly important in assessing which freshwater systems will be most susceptible to increases in salinity—the location of the systems in the landscape, and the current ecological condition of the system. The resilience of an ecosystem to salinity disturbances is shown to be a useful concept which with further knowledge may be incorporated into risk-assessment approaches.The development of a new ecological risk assessment approach for assessing risks to aquatic systems in the Goulburn–Broken catchment from increases in salinity over the medium (20 years) and long (100 years) term is reported. The risks to the biota in Hughes Creek, a tributary of the Goulburn River, are assessed by using a probabilistic approach. Current salinity levels in the creek present a low risk to the biota.Finally, the paper addresses the challenge of making the ecological risk assessment method more quantitative by discussing the following two key aspects: how to better quantify the linkages between the key stressors and the biotic components, and how to better handle uncertainties.

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Common insecticide disrupts aquatic communities: A mesocosm-to-field ecological risk assessment of fipronil and its degradates in U.S. streams

Science Advances ◽

10.1126/sciadv.abc1299 ◽

2020 ◽

Vol 6 (43) ◽

pp. eabc1299

Author(s):

Janet L. Miller ◽

Travis S. Schmidt ◽

Peter C. Van Metre ◽

Barbara J. Mahler ◽

Mark W. Sandstrom ◽

...

Keyword(s):

Risk Assessment ◽

Ecological Risk ◽

Ecological Risk Assessment ◽

The United States ◽

Aquatic Communities ◽

Stream Communities ◽

Low Concentrations ◽

Field Samples ◽

Multiple Regions ◽

Global Concern

Insecticides in streams are increasingly a global concern, yet information on safe concentrations for aquatic ecosystems is sparse. In a 30-day mesocosm experiment exposing native benthic aquatic invertebrates to the common insecticide fipronil and four degradates, fipronil compounds caused altered emergence and trophic cascades. Effect concentrations eliciting a 50% response (EC50) were developed for fipronil and its sulfide, sulfone, and desulfinyl degradates; taxa were insensitive to fipronil amide. Hazard concentrations for 5% of affected species derived from up to 15 mesocosm EC50 values were used to convert fipronil compound concentrations in field samples to the sum of toxic units (∑TUFipronils). Mean ∑TUFipronils exceeded 1 (indicating toxicity) in 16% of streams sampled from five regional studies. The Species at Risk invertebrate metric was negatively associated with ∑TUFipronils in four of five regions sampled. This ecological risk assessment indicates that low concentrations of fipronil compounds degrade stream communities in multiple regions of the United States.

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Lessons Learned in Ecological Risk Assessment Planning Efforts

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-2001-1-185 ◽

2001 ◽

Vol 2001 (1) ◽

pp. 185-190 ◽

Cited By ~ 2

Author(s):

Ann Hayward Walker ◽

Debra Scholz ◽

Don V. Aurand ◽

Robert G. Pond ◽

James R. Clark

Keyword(s):

Risk Assessment ◽

Ecological Risk ◽

Ecological Risk Assessment ◽

Puget Sound ◽

The United States ◽

Lessons Learned ◽

Federal State ◽

Bulk Oil ◽

Response Options ◽

Trade Offs

ABSTRACT There is growing interest in the United States for using the full mix of environmentally appropriate countermeasures during spill response to achieve the highest level of environmental protection and recovery possible. Determining the right mix of technologies, including mechanical recovery, shoreline cleanup, dispersants, and monitoring (no active response), is particularly challenging in sensitive and valuable estuaries through which high volumes of bulk oil shipment transit. This paper summarizes an ecological risk assessment (ERA) project to consider the potential effectiveness and effects of using dispersants, in addition to conventional countermeasures, to mitigate the impacts of oil spilled into the marine and nearshore environments and to facilitate preparedness efforts at the federal, state, local, and industry level. Sponsored by industry and federal and state agencies, the primary goal was to bring technical and resource experts together to use their collective knowledge and experience in methodically comparing the trade-offs associated with the use of various countermeasures in Puget Sound, Washington. The ERA process used for Washington State waters was the first ERA that specifically addressed oil spill response options in U.S. coastal estuaries. It occurred as a follow-up to several other preparedness activities jointly sponsored by government and industry. The project team learned several important lessons, which were used to refine the process as it subsequently was applied in California and Texas in 1999.

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