Pollutants bioavailability and toxicological risk from microplastics to marine mussels.

Publisher Summary The chapter focuses on mycological aspects of the genus Metarhizium . The genus includes several species, varieties within species, and individual isolates with broad ranges of physiological traits—including host range. The interactions of these fungi with their hosts, and the large literature on their use for pest control, largely define the scientific and popular concepts of Metarhizium spp. Fungi of the hyphomycete genus Metarhizium have been isolated from infected insects and soil. Although some isolates of these fungi have rather restricted host ranges, the group is better known for its ability to kill a wide spectrum of insects, including insects in at least seven orders. The common name for Metarhizium -induced disease is “green muscardine,” based on the encrustation of insect cadavers with green conidia. The rapid increase in research on Metarhizium , followed by sustained high scientific output, can be explained by several important worldwide attitude changes and the initiation of several promising Metarhizium -based pest-control and molecular-biology efforts.

Metarhizium spp., cosmopolitan insect-pathogenic fungi: mycological aspects.

We review the scientific literature, especially from the past decade, on the impacts of human activities on the Antarctic environment. A range of impacts has been identified at a variety of spatial and temporal scales. Chemical contamination and sewage disposal on the continent have been found to be long-lived. Contemporary sewage management practices at many coastal stations are insufficient to prevent local contamination but no introduction of non-indigenous organisms through this route has yet been demonstrated. Human activities, particularly construction and transport, have led to disturbances of flora and fauna. A small number of non-indigenous plant and animal species has become established, mostly on the northern Antarctic Peninsula and southern archipelagos of the Scotia Arc. There is little indication of recovery of overexploited fish stocks, and ramifications of fishing activity on bycatch species and the ecosystem could also be far-reaching. The Antarctic Treaty System and its instruments, in particular the Convention for the Conservation of Antarctic Marine Living Resources and the Environmental Protocol, provide a framework within which management of human activities take place. In the face of the continuing expansion of human activities in Antarctica, a more effective implementation of a wide range of measures is essential, in order to ensure comprehensive protection of the Antarctic environment, including its intrinsic, wilderness and scientific values which remains a fundamental principle of the Antarctic Treaty System. These measures include effective environmental impact assessments, long-term monitoring, mitigation measures for non-indigenous species, ecosystem-based management of living resources, and increased regulation of National Antarctic Programmes and tourism activities.

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Impacts of local human activities on the Antarctic environment.

Determining when contamination is pollution - weight of evidence determinations for sediments and effluents.

Low levels of oil and hence polycyclic aromatic hydrocarbons (PAHs) are naturally present in the marine environment, although levels have increased significantly following human extraction and use of oil and gas. Other major anthropogenic sources of PAHs include smelters, the use of fossil fuels in general, and various methods of waste disposal, especially incineration. There are two major sources for PAHs to marine ecosystems in Norway: the inshore smelter industry, and offshore oil and gas production activities. A distinction is generally made between petrogenic (oil-derived) and pyrogenic (combustion-derived) PAHs. Although petrogenic PAHs appear to be bioavailable to a large extent, pyrogenic PAHs are often associated with soot particles and less available for uptake into organisms. There is extensive evidence linking sediment-associated PAHs to induction of phase-I enzymes, development of DNA adducts, and eventually neoplastic lesions in fish. Most studies have focused on high-molecular-weight, carci...

Polycyclic aromatic hydrocarbon (PAH) ecotoxicology in marine ecosystems.

Weight of evidence (WOE) frameworks for integrating and interpreting multiple lines of evidence are discussed, focusing on sediment quality assessments, and introducing a series of ten papers on WOE. Approaches to WOE include individual lines of evidence (LOE) as well as combined LOE (indices, statistical summarization, logic systems, scoring systems, and best professional judgment [BPJ]). The application of WOE, based on multiple LOE, is discussed relative to the published literature. Fully implementing WOE requires consideration of six main LOE in sediment (or other assessments); these LOE generally correspond to other causality considerations including Koch's Postulates. However, the issue of sediment stability is an additional consideration, and the use of tabular decision matrices is recommended in a logic system to address LOE described by others as “analogy”, “plausibility”, or “logical and scientific sense.” Three examples of logic system WOE determinations based on the Sediment Quality Triad and ...

Weight-of-Evidence Issues and Frameworks for Sediment Quality (And Other) Assessments

Global geographic differences in marine metals toxicity.

PAH phototoxicity--an ecologically irrelevant phenomenon?

Toxicity reference values (TRVs) are essential in models used in the prediction of the potential for adverse impacts of environmental contaminants to avian and mammalian wildlife; however, issues in their derivation and application continue to result in inconsistent hazard and risk assessments that present a challenge to site managers and regulatory agencies. Currently, the available science does not support several common practices in TRV derivation and application. Key issues include inappropriate use of hazard quotients and the inability to define the probability of adverse outcomes. Other common problems include the continued use of no-observed- and lowest-observed-adverse-effect levels (NOAELs and LOAELs), the use of allometric scaling for interspecific extrapolation of chronic TRVs, inappropriate extrapolation across classes when data are limited, and extrapolation of chronic TRVs from acute data without scientific basis. Recommendations for future TRV derivation focus on using all available qualified toxicity data to include measures of variation associated with those data. This can be achieved by deriving effective dose (EDx)-based TRVs where x refers to an acceptable (as defined in a problem formulation) reduction in endpoint performance relative to the negative control instead of relying on NOAELs and LOAELs. Recommendations for moving past the use of hazard quotients and dealing with the uncertainty in the TRVs are also provided.

https://setac.onlinelibrary.wiley.com/doi/pdf/10.1897/IEAM_2009-010.1

Recommendations for the development and application of wildlife toxicity reference values.

A weight-of-evidence (WOE) framework was developed to evaluate potential effects on the aquatic ecosystem of Wabamun Lake (Alberta, Canada) associated with the release of Bunker “C” oil after a train derailment. The wide variety of stakeholders and interested regulatory agencies made it necessary to develop a consistent and transparent approach to assessing ecological effects on multiple ecosystem components within the lake with the use of a large number of lines of evidence (LOEs). Consequently, a scalable WOE framework was necessary to integrate the findings of 38 different LOEs. A priori and a posteriori weighting factors were applied to each individual LOE, and a combination of numeric and nonnumeric rating systems was used to integrate LOEs into an overall WOE conclusion for 5 different ecosystem components. We provide guidance regarding the development of a WOE framework and emphasize techniques that enhance the application of best professional judgement during the WOE process.

Blair G. McDonald

Papers

Weight-of-Evidence Issues and Frameworks for Sediment Quality (And Other) Assessments

Global geographic differences in marine metals toxicity.

PAH phototoxicity--an ecologically irrelevant phenomenon?

Recommendations for the development and application of wildlife toxicity reference values.

Design and application of a transparent and scalable weight-of-evidence framework: an example from Wabamun Lake, Alberta, Canada.