Studies on the acute toxicity of fluoride ion to stickleback,fathead minnow,and rainbow trout

We have studied the acute toxicity of fluoride ion to $\text{Gasterosteus aculeatus}$, $\text{Pimephales promelas}$, and juvenile $\text{Salmo gairdneri}$. LC50 values varied with species and (due to precipitation) initial water hardness. Exposure to elevated fluoride levels in water resulted in increased blood fluoride levels in $\text{Salmo gairdneri}$.     

a study of the temporal variability of atrazine in private well water. part i: study design, implementation, and database development

In 1988, the Iowa Department of Natural Resources, along withthe University of Iowa conducted the Statewide Rural WellWater Survey, commonly known as SWRL. A total of 686private rural drinking water wells was selected by use of aprobability sample and tested for pesticides and nitrates. Sixty-eight of these wells, the 10% repeat wells, were additionallysampled in October, 1990 and June, 1991. Starting inNovember, 1991, the University of Iowa, with sponsorshipfrom the United States Environmental Protection Agency,revisited these wells to begin a study of the temporalvariability of atrazine and nitrates in wells. Other wells, whichhad originally tested positive for atrazine in SWRL but werenot in the 10% repeat population, were added to the studypopulation. Temporal sampling for a year-long period beganin February of 1992 and concluded in January of 1993. Allwells were sampled monthly, one subset was sampled weekly,and a second subset was sampled for 14-day consecutiveperiods. Two unique aspects of this study were the use of animmunoassay technique to screen for triazines before gaschromatography/mass spectrometry (GC/MS) analysis andquantification of atrazine, and the use of well owners to samplethe wells. A total of 1771 samples from 83 wells are in thefinal data base for this study. This paper reviews the studydesign, the analytical methodologies, and development of thedata base. A companion paper (Pinsky et al., 1997) discussesthe analysis of the data from this survey.     

The Development of Biological Objectives for Streams in a Single Catchment: A Case Study on the Catchment of Western Port Bay, Victoria, Australia

Government environment protection policies for waterways have traditionally relied on water quality indicators and their objectives. In this paper we describe the development of biological objectives based on invertebrate indicators for inclusion in a government policy for the catchment of Western Port Bay, Victoria. The first step of defining segments (areas with streams in which the same objectives are applied) was problematic, requiring two different approaches, as follows. Site groups initially based on invertebrate community composition derived using multivariate techniques (ordination and classification) proved to be unsuitable for policy segments. Segment boundaries were subsequently defined using topographical (e.g. boundary of foothills and lowland plains), climate (e.g. rainfall) and land-use (e.g. urban) features. We used information and data from reference sites inside as well outside the catchment to derive specific biological objectives based on aquatic invertebrates for these segments. Objectives were specified for the following four indicators--number of invertebrate families, the SIGNAL index, the AUSRIVAS predictive model and the number of key families.     

Quantifying the relative irreplaceability of important bird and biodiversity areas

World governments have committed to increase the global protected areas coverage by 2020, but the effectiveness of this commitment for protecting biodiversity depends on where new protected areas are located. Threshold‐ and complementarity‐based approaches have been independently used to identify important sites for biodiversity. We brought together these approaches by performing a complementarity‐based analysis of irreplaceability in important bird and biodiversity areas (IBAs), which are sites identified using a threshold‐based approach. We determined whether irreplaceability values are higher inside than outside IBAs and whether any observed difference depends on known characteristics of the IBAs. We focused on 3 regions with comprehensive IBA inventories and bird distribution atlases: Australia, southern Africa, and Europe. Irreplaceability values were significantly higher inside than outside IBAs, although differences were much smaller in Europe than elsewhere. Higher irreplaceability values in IBAs were associated with the presence and number of restricted‐range species; number of criteria under which the site was identified; and mean geographic range size of the species for which the site was identified (trigger species). In addition, IBAs were characterized by higher irreplaceability values when using proportional species representation targets, rather than fixed targets. There were broadly comparable results when measuring irreplaceability for trigger species and when considering all bird species, which indicates a good surrogacy effect of the former. Recently, the International Union for Conservation of Nature has convened a consultation to consolidate global standards for the identification of key biodiversity areas (KBAs), building from existing approaches such as IBAs. Our results informed this consultation, and in particular a proposed irreplaceability criterion that will allow the new KBA standard to draw on the strengths of both threshold‐ and complementarity‐based approaches.     

Hydrodynamic modeling of Edmonton storm-water ponds

Environmental Fluid Mechanics - Computational models often are applied to simulate water quality for management of natural and constructed aquatic systems. As part of a larger study, a...     

Panel Bed Filters for Simultaneous Removal of Fly Ash and Sulfur Dioxide:

Experimental studies of the filtration of dilute aerosols of Dow microspheres by beds of sand have been conducted with flows passing vertically upward, vertically downward, and horizontally. With the use of Happel’s “free surface” model for a granular bed, the results can be correlated reasonably well by semiempirical, semitheoretical considerations taking into account collection by diffusion, gravity settling, direct interception, and inertial impaction. The results are preliminary to experiments to be made on filtration of aerosols by a filter cake of fly ash resting upon a sand bed.     

A high pressure liquid chromatographic method for the analysis of zearalenone in chicken blood

Abstract

A high pressure liquid chromatographic (HPLC) method is described to determine zearalenone in chicken blood. Samples are extracted with acetonitrile, followed by a hexane cleanup procedure and extracted further with ethyl acetate. The analysis of zearalenone is by HPLC using a reverse phase radial compression separation system, an ultraviolet absorbance detector and a mobile phase of acetonitrile‐water 60:40 (v/v). Recoveries of zearalenone in blood at levels of 50–200 ng/ml are in the range of 66.8–72.6%.