Development Of Water Quality Criteria Research Articles

Forest Streamwater Concentrations of Nitrogen and Phosphorus: A Comparison with EPA's Proposed Water Quality Criteria

Abstract To address the problem of excessive nutrients in US waters, the Environmental Protection Agency is developing water quality criteria for four types of waterbodies and 14 ecoregions. In this article we focus on total nitrogen and total phosphorus criteria for rivers and streams. A review of 300 streams draining small forested watersheds finds that nutrient concentrations often exceed EPA's proposed criteria. More detailed nutrient concentration patterns were evaluated for eight unmanaged research forested watersheds, three of which would have failed EPA criteria and been identified as impaired. Finer-scale tools would more precisely reflect water quality patterns and make the nutrient criteria rational, physically achievable, and biologically relevant.

A Comparative Study of the Sensitivity of Selected Aquatic Plants to Mining Effluents

Information is given on the relative sensitivity oftwo species of algae and three species ofmacrophytes to two effluents from a mining industry. As endpoints we used growth and radicle development. Alga1 (Ankistrodesmus bibraiirnus) growth and macrophyte radicle development endpoints were more sensitive than plant growth estimates, both weight and length. Chara globuluris was the least pollution-sensitive species, with the highest number of low or undetectable toxicity effects. Radicle development of Myriophyllum spicatum was more pollution-sensitive than that of Rantinculus sp. And also than the population growth ofA bibraianus. Their ease of use and sensitivity to pollution suggest that macrophytes have a great potential as tools for the development of water quality criteria.

Toxicity Assessment and Identification for Protection of Natural Waters

Conventional pollution prevention strategies for the protection of natural waters usually entail a comparison of analytical results with water quality guidelines. This comparison is often compromised by the inability to identify fully the toxicants in the environment and the need to reference current toxicological databases containing large data gaps. In light of these shortcomings, we describe examples of an alternative approach based on toxicity testing coupled with chemical manipulation and directed chemical analysis. Advantages of this toxicological approach over traditional methods are illustrated for natural water surveys conducted in North America and Mexico. It is demonstrated that toxicity identification evaluation is well suited to the development of water quality criteria for the protection of aquatic ecosystems.

Technical basis for narcotic chemicals and polycyclic aromatic hydrocarbon criteria. I. Water and tissue

AbstractA method is presented for developing water quality criteria (WQC) for type I narcotic chemicals in general and PAHs in particular. The criteria can be applied to any individual or mixture of narcotic chemicals using only the chemical's octanol‐water partition coefficientKOW. It is derived from a database of LC50s comprising 156 chemicals and 33 species, including fish, amphibians, arthropods, mollusks, polychaetes, coelenterates, and protozoans. A target lipid model is proposed that accounts for variations in toxicity due to differing species sensitivities and chemical differences. The model is based on the idea that a target lipid is the site of action in the organism. Further, it is assumed that target lipid has the same lipid‐octanol linear free energy relationship for all species. This implies that the slope of the log(LC50)–log(KOW) relationship is the same for all species. However, individual species may have varying target lipid body burdens that cause toxicity. The target lipid LC50 body burdens derived from concentration data in the water only are compared to measured total lipid LC50 body burdens for five species. They are essentially equal, indicating that the target lipid concentration is equal to the total extracted lipid concentration. The precise relationship between partitioning in target lipid and octanol is established. The species‐specific body burdens are used to determine the WQC final acute value, i.e., the 95‐percentile level of protection. An acute‐to‐chronic ratio is used to compute the body burden corresponding to the WQC final chronic value, which is the procedure used to derive the U.S. Environmental Protection Agency water quality criteria. The criteria are expressed either as dissolved concentrations in the water column or as tissue concentrations.

Interaction between phenanthrene and zinc in their toxicity to the sheepshead minnow (Cyprinodon variegatus).

Many contaminated sites contain a variety of toxicants. Risk assessment and the development of water quality criteria therefore require information on the interactive effects among toxicants in such mixtures. Interactions between metals are relatively well studied, but little is known about interactions between metals and hydrocarbons. This study investigated the interaction between phenanthrene and zinc in the sheepshead minnow Cyprinodon variegatus. Interaction studies were performed with 7-day-old minnows in 96-h bioassays with zinc and phenanthrene at a fixed ratio and with varying proportions of zinc and phenanthrene. Mixture toxicity was quantified with the toxic unit, additive index, and excess function methods. All three methods generally indicated an antagonistic interaction between phenanthrene and zinc, though the results also provide some evidence for a synergistic interaction at low toxicant levels or at specific phenanthrene-to-zinc ratios. Short-term uptake experiments were conducted to determine if the strong antagonistic interaction observed when zinc and phenanthrene were present at 50% of their LC50 values was due to effects of zinc and phenanthrene on each other's uptake. Significantly less 65Zn uptake occurred in the presence of phenanthrene than in its absence. In contrast, zinc did not appear to affect the uptake of 14C-phenanthrene.http://link. springer-ny.com/link/service/journals/00244/bibs/37n2p251.++ +html

Combined effects of alachlor and atrazine on benthic algal communities in artificial streams

AbstractA duplicated factorial approach was used to assess the combined effects of three environmentally realistic levels of alachlor (0.0, 5.0, and 90.0 μg/L), cross‐classified with three environmentally realistic levels of atrazine (0.0, 12.0, and 150.0 μg/L), on indigenous epipelic algae (mud‐dwelling species, characteristic of agricultural streams). The experiment was conducted in 18 recirculating laboratory streams over a 4‐week period. Biovolume of viable algal cells and relative abundance of the six dominant algal species were utilized as experimental endpoints. Community biovolume was impacted throughout the experiment in streams treated with 12.0 and 150.0 μg/L atrazine and in streams containing 90.0 μg/L alachlor, but only in samples collected at 4 weeks. The effects of atrazine and alachlor together on algal community biovolume appeared to be additive rather than synergistic. The relative abundance of two dominant algal taxa were impacted in streams treated with alachlor, but only one species remained affected over time. The lack of significant interactions is most likely attributable to the different modes of action of atrazine and alachlor. The additive nature of these two herbicides should be an important consideration in the development of water quality criteria.

A review of the effects of heavy metals on freshwater mussels

: The widespread recent decline in the species diversity and population density of freshwater mussels in North America may be partly related to chronic, low-level exposure to toxic metals. As benthic filter-feeding organisms, freshwater mussels are exposed to metals that are dissolved in water, associated with suspended particles and deposited in bottom sediments. Thus, freshwater mussels can bioaccumulate certain metals to concentrations that greatly exceed those dissolved in water. In adult mussels, the most common site of metal uptake is the gill, followed by the mantle and the kidney. The toxic effects of metals on freshwater mussels have been examined in a few acute toxicity tests, but the sublethal effects of long-term exposure to low environmental concentrations are little understood. Sublethal exposure to metals can alter growth, filtration efficiency, enzyme activity and behaviour. Sublethal effects are frequently observed at concentrations that are only half the lethal concentrations. However, few toxicity tests have used environmentally realistic exposure concentrations. Total concentrations of Cd, Cu, Hg and Zn in many oxic surface waters are in the ngl(-1) range, yet many toxicity studies have exposed mussels to concentrations in the μgl(-1) or even the mgl(-1) range. An understanding of the processes by which metals affect freshwater mussels would provide insights on the ecotoxicological significance of metal contamination to natural mussel populations and aid in the development of water-quality criteria that adequately protect mussels.

Perspective on a career: Changing approaches to water pollution evaluation

Doctor Michael Waldichuk was the first (1954) scientist to be appointed a full-time worker on water pollution, for the Canadian department of fisheries. He started his career as a chemical oceanographer on the Pacific coast, and over many years he applied those skills to surveys of pulp mill pollution. His remarkable achievement, however, was to broaden his approach continually during 39 years of work. He wrote discerning technical reports and reviews of methods in marine toxicology, enrichment of waters, atmospheric interactions, approaches for developing water quality criteria, and strategies for controlling global pollution, among other things. He was a long-time and honoured participant in international committees and expert groups dealing with marine pollution.

A statistical bias in the derivation of hardness-dependent metals criteria

Log-transformed values of lethal effect and hardness are often employed to predict metal effects. For example, they are used to develop water quality criteria. A statistical bias encountered with backtransformed, least-squares regression models can compromise the accuracy of associated predictions. A description and method of estimating this bias are discussed herein. In a selected data set, the bias was as high as 57%.

Planarians in toxicology. Responses of asexualDugesia dorotocephala to selected metals

The planarian Dugesia dorotocephala is a freshwater invertebrate found in unpolluted flowing surface waters. Planarians have a sensitive nervous system with synapses and true brain and evidence these in a variety of social and response behaviors. The inclusion of planarians in a screening battery would provide improved sensitivity in detecting toxicity because planarians commonly respond to lower levels of contamination than do other species. Numerous toxicity test have been conducted to determine the acute and chronic effects of toxicants to provide data necessary for the development of water quality criteria. The appropriateness of Illinois water quality standards for metals was investigated using a 1-hr behavioral test based on the responses of the planarian D. dorotocephala. One possible difficulty with water quality standards for metals is that the standard for each metal is usually established without regard to the effects of other metals present in the receiving water.

Dioxin bioaccumulation: Key to a sound risk assessment methodology

Human exposure to many pollutants occurs primarily through the ingestion of contaminated fish. In order to protect human health, regulatory agencies set limits on the levels of pollutants entering water bodies from point sources, thereby limiting the amount of pollutants that may be accumulated by fish. The limits, in the form of water quality criteria, are designed to correlate the concentration of a pollutant in a water body (and therefore the concentration accumulated by a fish) to the risks to humans. This type of model provides a reasonable way of controlling pollutants from point sources if the assumptions used in the model are realistic. However, the risk assessment formula currently used for developing water quality criteria only considers those pollutants in the water column available to fish through bioconcentration across the gills (freely dissolved pollutants). For strongly hydrophobic pollutants like dioxin, an extremely small fraction of the total amount is freely dissolved; most dioxin is sorbed to organic matter and is ingested by fish. A new model for developing criteria is presented here that takes into account the environmental fate of dioxin (predominantly in the sorbed state in the environment) and that fish accumulate dioxin by ingestion, rather than bioconcentration.

Chronic toxicity of aniline and 2,4-dichlorophenol toDaphnia magna Straus

Data generated from daphnid chronic toxicity tests are used by various regulatory agencies for the development of water quality criteria. Two chemicals which are lacking reported chronic data are aniline and 2,4-dichlorophenol. The acute toxicity of 2,4-dichlorophenol to Daphnia magna has been reported; the toxicity of aniline to D. magna also has been reported. Chronic data for these chemicals are lacking for invertebrates. The objective of this study was to estimate the chronic toxicity of aniline and 2,4-dichlorophenol to Daphnia magna Straus, using a standard 21-day static renewal procedure.

Soviet-American Cooperation in the Field of Protecting Water from Pollution

Anthropogenic effects on aquatic resources in the US and USSR are briefly discussed as a background for the efforts undertaken by participants in Project 02.02–13, The Effect of Pollutants on Aquatic Organisms and Ecosystems: Development of Water Quality Criteria, under the US-USSR Joint Agreement on Environmental Protection. The objectives of this project are to jointly identify pollutants of mutual concern, to exchange information and methodologies, to assess effects of the pollutants on aquatic organisms and ecosystems, and to recommend appropriate water quality criteria. Investigations in progress have focused on toxicity of ammonia in different kinds of receiving systems, effects of organophosphate insecticides, degradation of pollutants by microorganisms, and development of behavioral methods for assessing effects of pollutants on aquatic organisms. Since 1975, the Project has sponsored five joint symposia and has produced nearly 100 scientific publicaitons.

A fathead minnow Pimephales promelas early life stage toxicity test method evaluation and exposure to four organic chemicals

A 32-day test was developed at the Environmental Research Laboratory—Duluth for conducting early life stage (ELS) toxicity tests with fathead minnows Pimephales promelas. These test procedures were evaluated by using the prescribed methods to establish estimated maximum acceptable toxicant concentrations (MATC) for fathead minnows exposed to four previously untested organic chemicals. Toxic effects on early developmental stages demonstrated that larval growth and survival were the most sensitive indicators of toxic stress. Embryo hatch and larval deformities at hatch were the least sensitive indicators of toxicity. The estimated MATCs for fathead minnows exposed to hexachlorobutadiene, 1,2-dichloropropane, 1,3-dichloropropane and 1,2-dichloroethane lie between 6·5 and 13 μg litre −1, 6 and 11 mg litre −1, 8 and 16 mg litre −1 and 29 and 59 mg litre −1, respectively. Results obtained from the four ELS test method evaluations and the estimated MATCs derived from these evaluations demonstrate the consistency of the ELS toxicity test procedures for fathead minnows currently being adopted as standards by the US Environmental Protection Agency and the American Society for Testing and Materials. These ELS test methods produced good replication and, when used to predict long-term chronic toxicity, will provide a rapid means to develop water quality criteria and screen large numbers of single chemicals or complex effluents.

Environmental quality criteria: Some considerations

The physicochemical characteristics of the recipient environment into which chemical contaminants are deposited may influence their chemical speciation, mobility, bioavailability, and toxicity. In formulating Water Quality Criteria, the Environmental Protection Agency of the United States (EPA) considered the modifying effect of abiotic environmental factors on pollutant toxicity in an innovative regulatory approach. Scientific knowledge of the interactions and correlations between pollutant toxicity and abiotic factors remains limited. Recognition of the influence of the physicochemical characteristics of the recipient environment on pollutant toxicity has implications for the eventual formulation of regional, rather than uniform and national, criteria. In addition, in developing Water Quality Criteria that incorporate the effects of pollutants on “aquatic life,” EPA primarily focused on toxicity to aquatic animals and plants (including unicellular algae). The effects of pollutants on microbe-mediated ecological processes that are necessary for maintaining the state and quality of the ecosphere (such as biogeochemical cyclings, litter decomposition, and mineralization) were not included in the formulation of the Water Quality Criteria. To facilitate the recognition and quantification of adverse effects of pollutants on these ecological processes, the development of a computation, termed the “ecological dosage 50%” (EcD50) is recommended. Such a formulation could also be applied to setting environmental quality criteria for terrestrial ecosystems.

Human health hazards associated with chemical contamination of aquatic environment.

Given the finite supply of water available for human use, continued chemical contamination of the aquatic environment may pose a significant human health hazard. Consequently, an effort must be made to develop ambient water quality criteria to protect human health and preserve the integrity of the aquatic environment. In developing water quality criteria based on human health effects, information on sources of exposure, pharmacokinetics, and adverse effects must be carefully evaluated. Information on sources of exposure is needed to determine the contribution of exposure from water relative to all other sources. Pharmacokinetic data are used in inter- and intraspecies extrapolation and in characterizing the mode of toxic action. Information on toxic effects includes data on acute, subchronic, and chronic toxicity, mutagenicity, teratogenicity, and carcinogenicity. In analyzing such information, a distinction is made between threshold and nonthreshold effects. Currently, carcinogenicity and mutagenicity are considered to be nonthreshold effects. For carcinogens and mutagens, criteria are calculated by postulating an "acceptable" increased level of risk and using extrapolation models to estimate the dose which would result in this increased level of risk. For other chemicals, thresholds are assumed and criteria are calculated by deriving "acceptable daily intakes" for man which would presumably result in no observable adverse effects. Neither process is exact, and attempts must be made to improve and verify risk assessment methodologies.

The development of water-quality criteria for marine fisheries

Abstract The formulation of water-quality criteria (or standards) for marine fisheries is considered in the light of a decade of experience by the European Inland Fisheries Advisory Commission in relation to freshwater fisheries. The relevance of laboratory data on the graded responses of organisms to pollutants under control conditions and of communities in artificial eco-systems and field situations is discussed, the importance of the latter being stressed for the identification as well as the elucidation of problems. The possibility of basing criteria on mass flows as well as on aqueous concentrations of pollutants is raised, together with the need for considering different levels of protection and the means of taking account of a variable pattern of fluctuation in water quality. Finally, the importance of basing criteria upon a critical assessment of the literature, particularly that on well documented problems under field conditions, is stressed.

Sociological and Technological Factors in Developing Water Quality Criteria

Sociological and Technological Factors in Developing Water Quality Criteria