Showing papers in "Bulletin of Environmental Contamination and Toxicology in 1987"

Acute toxicity of uranium in rats and mice.

Abstract: The enormous expansion in the mining, processing, use and operations involving uranium that has occurred over the last forty years has led to the dispersion of concentrated uranium at many sites over almost the entire world. While the dangers due to nuclear reactions are given wide play in the public press, the toxicological hazards of increased levels of uranium are less widely appreciated. On the other hand, during uranium processing there is a possibility that workers will inhale or ingest some uranium, giving rise to internal contamination. This contamination will result in radiation doses to the organs of the body, and if the intake of uranium is large enough, chemical toxic effects. Under some circumstances the toxic chemical effects of uranium may be more important than the radiation dose received. The interest of this question has increased following the accident at Chernobyl on 26 April 1986. Many details are still unknown concerning the exact nature of the Chernobyl accident. However, it is known that Chernobyl reactor was fueled with about 200 tons of uranium dioxide packaged in 1661 fuel assemblies.

Seasonal toxicity of ammonia to five fish and nine invertebrate species.

Abstract: Ammonia is a widely distributed chemical found in surface waters. Its toxicity to aquatic life is principally due to the un-ionized (NH3) form. An extensive review on ammonia toxicity to aquatic life has been recently compiled by the US EPA with most information consisting of fish test values and limited data available for aquatic plants and invertebrates. Invertebrates were found to be generally more tolerant to ammonia than were fishes. This laboratory study is part of a larger evaluation in assessing the impact of ammonia nitrogen in outdoor experimental streams at and above derived water quality criteria concentrations. Primary objective for this laboratory study was to determine the relative sensitivity of un-ionized ammonia to fish and invertebrates in river water at ambient seasonal temperatures.

Decreased survival and teratogenesis during laboratory selenium exposures to bluegill, Lepomis macrochirus.

Abstract: Bluegill (Lepomis macrochirus) embryo-larval studies using eggs of feral fish from a selenium-contaminated reservoir found low larval survival and teratogenesis when ovarian selenium concentrations were high. Since dietary sources supply most of the selenium that accumulates in fish, the authors hypothesized that reproductive impairment could occur if the dietary concentrations were sufficiently elevated and the chemical form of selenium was equivalent to the form experienced by the fish in the environment. This hypothesis was studied in a partial life cycle test by comparing the effects of chronic dietary exposure of selenomethionine (SeMet) and selenite (Se4+) to bluegill sunfish. They also tested one combination of dietary SeMet and waterborne Se4+. SeMet was selected as the organic form because in a preliminary study its accumulation was most similar to that of naturally occurring selenium in bluegill. Se4+ was selected as the inorganic form because it is the predominant oxidation state in some contaminated cooling reservoirs. The authors demonstrate that for larval bluegill (1) elevated dietary selenium exposure to parent fish causes teratogenesis and decreases larval survival, (2) parental dietary organoselenium is more toxic than dietary inorganic selenium, and (3) the combination of parental dietary, plus waterborne exposure, is more toxic than dietary more » exposure alone. « less

Metabolism of monocrotophos and quinalphos by algae isolated from soil

Abstract: but selective with concentrations,enhancement in the growth of soll algae has been reported (Megharaj et al. 1986). The capabilities of five algal species, isolated from a vertisol, to degrade monoerotophos and quinalphos, the most effective insecticides in controlling cotton bollworms, were determined in the present study. MATERIALS AND METHODS To determine the role of soil algae in the degradation of monoorotophos (Dimethyl (E)-1-methyl-2- methyl carbamoylvinyl phosphate) and quinalphos (O,O-diethyl-Oquinoxalin -2- yl phosphorothioate),enPichment cultures were prepared by adding ! ml of I000 ppm aqueous solutions from the commercial formulation of each insecticide separately to 20-g portions of the soil samples, maintained at 50% of water-holding capacity. After five additions, at 15-day intervals, of each chemical, the soil samples were withdrawn for isolation of predominant algae following the most-probable number (MPN) method as described earlier (Muralikrishna and VenMateswarlu 1984). Axenic cultures were developed from the most common and consistently occurring forms in almost all the MPN tubes. Two green algae, Chlorella vulqaris Beljerinck and $~enedesm~ biJuaatus (Turpin) Kuetzing, and three species of blue-green algae (cyanobacteria)

Correlation between heavy metal acute toxicity values in Daphnia magna and fish.

Abstract: In the toxicant bioassays, invertebrates with special reference to aquatic arthropod species have been of recent interest as test models due to the need for developing nonmammalian tests system. The cladoceran Daphnia magna bioassays have several practical advantages. D. magna has been used as a useful test species and its sensitivity to environmental pollutants have been recognized as a general representative of other freshwater zooplankton species. The objectives of this study were to determine the acute toxicity of various heavy metals to Daphnia magna for 48 h of exposure and to compare these values with the existing LC50 values for rainbow trout (Salmo gairdneri); which is commonly used as a test animal in aquatic bioassay studies.

Heavy metal accumulation in the mole, Talpa europea , and earthworms as an indicator of metal bioavailability in terrestrial environments

Abstract: Bioaccumulation studies in animals can supply valuable information to supplement the data obtained by chemical analysis of pollutants in abiotic samples. With respect to the terrestrial ecosystem, suitable indicator species in the decomposer subsystem can be identified on the basis of functional characteristics and trophic level. Investigations on metal behavior at the first trophic level, done in lumbricid earthworms showed that the potential for bioaccumulation depends on the degree of contamination as well as on the metal-binding capacity of the soil. The present study was performed to investigate metal behavior at a higher trophic level, and the mole (Talpa europea) was chosen a representative of the terrestrial decomposer subsystem. As earthworms are the preferred food of moles, they provide the major source of ingested metals to these animals. The food chain involving earthworms and moles provides an example of a critical pathway for potentially toxic non-essential metals such as cadmium and lead.

Lead and cadmium contamination levels in edible vegetables

Abstract: The objective of this research is to reveal the level of lead and cadmium pollution in fresh vegetable samples from the Cordovan fertile lowland region of the Guadalquivir River and to establish a base level of contamination to serve as a reference point in further studies. At the same time, the possible health risks for the consumer are discussed.

As, Cd, Cu, Pb, Hg, and Zn in fish from the Alexandria region, Egypt.

Abstract: Metals such as mercury, cadmium, arsenic, and copper tend to accumulate in bottom sediments from which they may be released by various processes of remobilization, and can move up the food chain, thereby reaching man where they could produce chronic an acute ailments. Investigations of metals in fish are an important aspect of environmental pollution control because human activities progressively increase the concentration of heavy metal in the aquatic system. The study of fish muscle tissue is one of the means for investigating the amount of heavy metals reaching man by the food chain and has therefore been investigated more than other organs. In Alexandria, pollutant metals may be derived from anthropogenic activities, especially from industrial and agricultural wastes from several major drains. Idku and Maryut lakes are characterized by fish productivity. All of them receives waste waters from several drains. The purpose of this study was to determine metal concentrations in fish samples collected from Abu Qir Bay, Idku Lake and Maryut Lake.

Mammalian mitochondria as in vitro monitors of water quality.

Abstract: To measure acute toxicity effectively, a system must provide a simple, sensitive, and rapid measurement of physiological parameters which are indicative of overall organism (bacteria) or organelle (mitochondria) viability. To detect a broad spectrum of toxicants, the parameters should be associated with a major metabolic process controlled by interdependent enzyme systems. In the bioassay reported here, phosphorylating submitochondrial particles (SMP), prepared by sonic disruption of the heavy fraction of intact bovine heart mitochondria serve as in vitro monitors of aquatic toxicity. The bioassay is based on the phenomenon of energy-coupled reverse electron transfer (RET), discovered in plant mitochondria, and later explored using SMP preparations from mammalian sources. RET responses permit rapid, simple, and sensitive measurement of acute toxicity by spectrophotometric recording of the rate of NAD reduction. The criterion of toxicity in this test is inhibition of NAD reduction in the presence of toxic substances. The RET reaction was chosen over other methods because responses are easily quantifiable and the energy-coupled RET reaction is competent in reconstituted freeze-dried submitochondrial particles. Thus, SMP - a stable biological preparation- can be distributed to other laboratories. This feature is important in selecting a routine bioassay.

Copper, cadmium, and nickel accumulation in crayfish populations near copper-nickel smelters at Sudbury, Ontario, Canada.

Abstract: The Sudbury basin, an elliptical 646 square mile depression containing a number of freshwater reservoirs, has been subjected to extreme ecological disturbances from logging, mining and smelting activities. The purpose of the present study was to compare tissue concentration of copper, cadmium and nickel in freshwater crayfish at selected distances of the habitat from the emission source. Various tissue concentrations in crayfish from the sites were also examined to determine if particular body tissues were specific sites for metal accumulation.

Sensitivity of toad tadpoles, Bufo melanostictus (Schneider), to heavy metals.

Abstract: Amphibian larval stages have several qualities which make them as a useful indicator of harmful levels of pollutants in bioassay tests. Amphibian tadpoles show a variety of sublethal responses such as changes in growth, development rates, pigmentation and expression of morphological deformities in a lesser time of exposure to the environmental pollutants. The objective of the work reported in this paper was to determine the acute toxicity of cadmium, copper, chromium, mercury, nickel, silver and zinc to the tadpoles of toad Bufo melanostictus (Schneider), which is commonly available and breed in aquatic habitats exhibiting a wide range of temperature and varying water quality.

Effect of early postnatal exposure to polychlorinated biphenyls (PCBs) on fertility in male rats.

Abstract: Males exposed to PCBs during lactation exhibited reduced fertility, i.e., reduced incidence of implantation in normal females mated to experimental males. However, a reduced weight gain during the time of treatment in the pups exposed to the higher doses of PCBs was also observed. After treatment, weight gain was comparable or greater in the experimental pups and by the time of mating and autopsy, body weights in all groups were comparable. The present experiments were designed 1) to determine if the early reduced weight gain (previously observed) has any influence on fertility, and 2) to investigate the effect of early postnatal exposure to PCBs on sperm counts and the ability of the sperm to support normal development.

Application of an enzyme-linked immunosorbent assay (ELISA) to determine paraquat residues in milk, beef, and potatoes.

Abstract: The USDA Food Safety and Inspection Service (FSIS) has included paraquat on its list of compounds to be considered for monitoring in foods. However, present methods do not easily accommodate the processing of large numbers of samples, thus limiting routine monitoring of the compound. The conventional method, based on spectrophotometry of reduced paraquat solutions, requires time-consuming sample preparation. Although the advantages of immunoassays for pesticide residue analysis have been pointed out, the reported immunoassays for paraquat have only been applied to cases of clinical poisoning or human exposure assessment. In this study, spiked milk, potato, and beef were analyzed directly, without prior cleanup, by an enzyme-linked immunosorbent assay (ELISA).

Impact of chronic lead poisoning on the hematological and biochemical profiles of a fish, Barbus conchonius (Ham)

Abstract: The contamination of natural waters by lead is mostly caused by a variety of anthropogenic activities related to increased mining operations and industrial uses of this metal. Adverse effects of lead poisoning in the fishes have been reported with references to both hematological and biochemical variables. The aim of present investigation was to study the effects of chronically administered sublethal levels of inorganic lead on the hematological and biochemical profiles of widely distributed freshwater fish, Barbus conchonius. The variables such as erythrocyte numbers, hemoglobin, hematocrit, mean corpuscular volume, blood glucose, glycogen in liver, skeletal muscles, and myocardium, and cholesterol in blood, liver, ovary, and testes were evaluated.

Changes in selected biochemical parameters in the kidney and blood of the fish, Tilapia mossambica (Peters), exposed to heptachlor

Abstract: Pesticides used in pest control programs seem to produce many physiological and biochemical changes in fresh water organisms by influencing the activities of several enzymes. Alterations in the chemical composition of the natural aquatic environment usually effect behavioral and physiological systems of the inhabitants, particularly of the fish. Although some data are available on the effects of different pesticides on the biochemical aspects of fish gill, data on heptachlor toxicity on T. mossambica kidney are lacking. Therefore, an attempt has been made to observe certain biochemical paramets of fish, T. mossambica under heptachlor intoxication. Investigation of this nature is useful in understanding the orientation of biochemical changes during sublethal toxicity to ascertain the degree of intensity of the toxicity of heptachlor on the kidney.

Some properties of azoreductase produced by Pseudomonas cepacia.

Abstract: As for the recent research on azoreductase, (i) the reduction mechanism of azoreductase by hepatic cell-free extracts or rat internal contents, (ii) the spectrophotometric determination for the enzyme by rat hepatic microsome, and (iii) the fluorophotometric determination for rat liver cytosol using Methyl Red as a substrate were studied. There is no research on the purification of the enzyme and also on identification of metabolic intermediates using labelled compounds as substrates. In a previous paper, the microorganism, which degraded p-aminoazobenzene into aniline and p-phenylenediamine was isolated from waste waters of dyestuff industries in the Gifu district, Japan, and also reduction, oxidation and acetylation of p-aminoazobenzene were reported. In this paper, the authors describe partial purification procedure of azoreductase, some properties of the azoreductase and identification of degradative intermediates, p-phenylenediamine and aniline, from p-aminoazobenzene using two types of (/sup 14/C)-labelled p-aminoazobenzenes.

Effects of temperature on the acute toxicity of heavy metals (Cr, Cd, and Hg) to the freshwater crayfish, Procambarus clarkii (Girard).

Abstract: Chromium, an essential trace element for humans and animals is involved in normal carbohydrate metabolism; however, it is toxic at high concentrations. There is no evidence that cadmium and mercury are biologically essential but their toxicity for organisms is well known. Both cause toxic effects at low concentrations to most organisms, especially in combination with other environmental variables such as temperature. Lake Albufera and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic industrial residues (including heavy metals) from the many urban and waste waters in this area. In 1978, the American red crayfish Procambarus clarkii appeared in lake Albufera and in the surrounding rice fields. Without adequate sanitary control, the crayfish is presently being fished commercially for human consumption. The purpose of the present study is to evaluate the degree of toxicity of various heavy metals (chromium, cadmium and mercury) to freshwater crayfish Procambarus clarkii at various temperatures.

Effect of cadmium on oviposition and egg viability in Chironomus riparius (Diptera: Chironomidae).

Abstract: Although the importance of toxicity data on freshwater macroinvertebrates for establishing water quality criteria is now well recognized few attempts have been made to determine the relative sensitivities of different life stages or ages within a species. Previous work with insects has suggested that earlier life stages may be more sensitive than later ones although toxicant effects on the egg itself have been virtually ignored. The selection of water of a suitable quality for egg-laying has been demonstrated in mosquitoes. However, there is virtually no information available on oviposition behavior in relation to toxicant stress or water quality although some authors have speculated on the presence of chemo-receptors in insect antennae and their possible involvement in testing water quality prior to oviposition. The present study aimed to investigate the extent of selection by Chironomus riparius females between a range of cadmium solutions as sites for oviposition and the effect of cadmium on egg hatching.

Effect of sub-chronic lindane exposure on humoral and cell-mediated immune responses in albino rats

Abstract: The present study was designed to evaluate the effect of sub-chronic doses of endosulfan on humoral and cell-mediated immune (CMI) responses in albino rats. Male albino rats were given a diet containing 5, 10 or 20 ppm endosulfan for 8–22 weeks and immunized with tetanus toxoid in Freund's complete adjuvant subcutaneously 20 days before terminating the exposure. The humoral immune response was studied by serum globulin level, immunoglobulin (IgM and IgG) concentration and antibody titre against tetanus toxoid. The CMI response was studied by leucocyte migration inhibition (LMI) and macrophage migration inhibition (MMI) factors. The antigen-induced increases in serum globulin fraction and immunoglobulin level were reduced at high doses of the endosulfan after 12 weeks of exposure. Antibody titre was significantly decreased in endosulfan-exposed rats at 10 and 20 ppm levels and a consistent trend was observed. Rats in the 10 and 20 ppm dose groups had significantly depressed LMI and MMI responses. Results obtained in this study revealed marked suppression of the humoral and CMI responses in rats administered with sub-chronic doses of endosulfan. Both cellular and humoral immune responses were decreased in a dose-time dependent pattern. Suppression of immune responses by endosulfan is clearly an important aspect of its toxicology.

Chlorinated pesticide residues in sediments from the Arabian Sea along the Central West Coast of India

Abstract: The problem of environmental contamination by persistent chlorinated pesticides still evokes major concern due to the presence of their residues in the environment and in human tissues. In developing countries like India organochlorine insecticides, especially DDT are extensively being used in agriculture and vector control programs. Few data are available on their levels of concentration from the seas around India. Persistent pesticides residues can be expected to accumulate in marine sediments. However, very little data on this are available along the Indian coast. An attempt has been made in the present communication to identify and quantify some of the chlorinated pesticides residues in the marine sediments collected from different region along the central west coast of India. This is a part of our ongoing project to monitor and map pollutants within the exclusive economic zone of India.