Toxicity of textile waste to some teleost fishes

LC50 values for different periods, acute toxicity ranges and presumable harmless concentrations, along with relative susceptibility of a few freshwater teleost fish to textile waste have been determined. The presumable harmless concentration to regulate the disposal of this waste was 1.1254, 0.4966, 0.9912, 1.0157, and 1.086% by volume for fish, Saccobranchus fossilis, Labeo rohita, Notopterus notopterus, Colisa fasciatus, and Ophiocephalus punctatus respectively.     

Nickel induced hyperglycemia in the freshwater fish,Colisa fasciatus

Effect of nickel sulphate at the sublethal dose of 64 ppm (0.8 of LC50 96 hr) on the blood glucose levels of the freshwater fish, Colisa fasciatus, has been estimated from 3 to 96 hr. The blood glucose level exhibits a steady increase due to Ni toxicity. A maximum increase of 85.08% is observed at 96 hr (P < 0.001). It is suggested that the hyperglycemia in C. fasciatus, caused by exposure to nickel sulphate, is possibly a reflection of stress-induced hormone mediated response. It appears that the blood glucose level is a reliable indicator of Ni toxicity to fish.     

Effects of environmental and biological variables on the toxicity of mercuric chloride

This study evaluated the effects of environmental and biological variables on the toxicity (LC₅₀) of mercuric chloride on the fish Notopterus notopterus. The results reveal that the change in temperature, dissolved oxygen, pH and fish size in experiments is highly significant both at 1 and 5% levels except in size, where it is insignificant at 1% level.     

Effect of sublethal concentrations of mercury on the composition of liver,muscles and ovary of Notopterus notopterus

The present investigation was undertaken to evaluate the effect of sublethal concentrations (0.088 and 0.044 mg 1^?1, i.e., 1/5th and 1/10th fraction of 96 h LC₅₀) of mercuric chloride on Ca, inorganic phosphate, water content, ash, glycogen, Fe, total protein, lipid contents and vitamin A, C, D, and E of liver, muscles and ovary of the freshwater fish Notopterus notopterus exposed for 30 days. The results obtained indicate that Ca, inorganic phosphate, water, ash, glycogen, Fe, total protein contents and vitamin D decreased significantly or insignificantly in these tissues of the Hg exposed fishes. However, lipid content increased in liver and muscles, but decreased in the ovaries. Vitamin A and D increased in the liver but decreased in the muscles and ovaries. Moreover, vitamin E increased in all the tissues of the fish exposed to 0.088 mg 1^?1 and decreased in the fish exposed to 0.044 mg 1^?1 of Hg concentrations.     

Role of ascorbic acid in the toxicity of pesticides in a fresh water teleost

The effect of ascorbic acid and pesticides (thiotox and malathion) on certain haematological parameters of a fishSaccobranchus fossilis was studied. The sublethal concentrations of thiotox (0.002 mg l^?1) and of malathion (5.2 mg l^?1) were tested. Ascorbic acid (2mg 100 g^?1 body weight) was given with food. The alterations in haematological parameters (CT, PT, Hb, RBC, WBC, ESR, PCV, MCH, MCHC, MCV, glucose, protein, total P, Na, K, Mg, Ca, and Cl) were measured after 15 and 30 days exposure. Thiotox and malathion induced significant alteration in blood parameters while ascorbic acid played a protective role.     

Subacute stress induced by sodium lauryl sulphate (SLS) on certain haematological parameters in Saccobranchus fossilis

Fish Saccobranchus fossilis were exposed to various subacute levels (0.45, 0.56, 0.75, 1.12, and 2.24 mg l^?1) of sodium lauryl sulphate (SLS) for periods of 30 and 60 days, and the haematological response in blood was investigated. A significant fall (P < 0.05) in coagulation time was observed after 30 days exposure to 2.24 mg l^?1 and 60 days exposure to 1.12 and 2.24 mg l^?1 of this syndet. Reduction of haemoglobin, at RBC and WBC was observed at all the syndet levels and at both the exposure periods. Significant (P < 0.05) increases in hematocrit values were noted at 2.24 mg l^?1 of SLS at both exposures.     

Effects of a chromated-copper-arsenate wood preservative on the growth of a pentachlorophenol degrading bacterium

A chromated-copper-arsenate (CCA) wood preservative was tested for toxic effects on the growth of a bacterial culture (Flavobactenum sp. ATCC 53874) capable of biodegrading pentachlorophenol, another wood preservation chemical. Both a commercially available CCA preparation and a laboratory-prepared CCA solution were tested. Each had an inhibitory effect on the growth of Flavobacterium at diluted CCA levels as low as 1.0×10^?4 to 1.0×10^?5% wt vol^?1. The commercial formulation was generally more toxic. EC₅₀ values calculated after 96 hr of incubation were 1.2 ×10^?4% wt vol^?1 for the commercial material (containing 0.15/0.097/0.14 μg mL^?1 of Cr/Cu/As, respectively) and 3.8×10^?4% for the laboratory solution (containing 0.51/0.31/0.49 μg mL^?1 of Cr/Cu/As, respectively). CCA toxicity increased during the first 7 to 8 days and then slowly decreased for the balance of the 21 day incubation period. Biodegradation of pentachlorophenol residues in contaminated soil will be negatively affected by the presence of CCA as a co-contaminant.     

Effect of composting and number of flocks on poultry litter extract bod and toxicity

Changes in poultry litter's (aqueous extract) biochemical oxygen demand (BOD) and toxicity, to photobacterium phosphoreum, calculated as EC₅₀ values, with the time of composting and the number of flocks raised, before cleaning the house, were studied. The BOD of the extract (5 g L^?1) is comparable to that of raw sewage and it increased with the time of composting, following a first order kinetics. The extract showed a toxicity higher than the toxicity of a solution of 25 ppm phenol. Increasing the number of flocks raised (from 2 to 15), before cleaning the house, reduced both the litter's BOD (22%) and toxicity (66%).     

Responses of Photosynthetic Efficiency,Cell Shape and Motility in Euglena gracilis (Euglenophyceae) to Short-Term Exposure to Heavy Metals and Pentachlorophenol

Euglena gracilis was exposed for 24 hr to concentrationsof copper, nickel, lead and zinc ranging from 0.1 to 2.0 mg L^-1 and to pentachlorophenol ranging from 0.1 to 10.0 mg L^-1. Photosynthetic efficiency (PE) was inhibited by increasing concentrations of the heavy metals. Nickel was foundto be the least toxic of the metals to E. gracilis, whilethe other three metals exhibited similar levels of toxicity. Treatment with pentachlorophenol caused unusual responses of the photosynthetic apparatus probably due to the especially high toxicity of this substance. Both cell shape and motility turned out to be insensitive physiological parameters for the toxicity testing of the substances studied.     

Gill damage to catfish,Saccobranchus fossilis following exposure to chromium

Air-breathing catfish, Saccobranchus fossilis, were exposed to 5.6 mg L^?1 of Cr for 7 d under static bioassay conditions. Gill tissue was examined through the scanning electron microscope (SEM) for surface morphological changes. In the control fish, the gill epithelium on primary and secondary lamellae contained distinctive surface features consisting of whorled patterns of microridges (microfolds) with intervening grooves. The microridges and grooves on the primary lamellae surface were regular in their architecture; whereas, the microridges of secondary lammellae were further apart and discontinuous. Small pores were observed on primary and secondary lamellar epithelium. SEM study of chromate exposed gill morphological data revealed that hyperplastic reaction start locally in the primary and the secondary lamellar epithelium. It appears that the hyperplastic results from direct chromate damage to the epithelial cells. Other gill damages were edema, fusion of secondary gill lamellae and degeneration of epithelial cells. Marked ultrastructural alterations in the pattern of microridges and intervening grooves, and swelling of primary and secondary epithelial cells were evident at 5.6 mg L^?1 of Cr level.     

Microbial and non-biological decomposition of chlorophenols and phenol in soil

The aerobic and anaerobic degradation of phenol and selected chlorophenols was examined in a clay loam soil containing no added nutrients. A simple, efficient procedure based on the high solubility of these compounds in 95% ethanol was developed for extracting phenol and chlorophenol residues from soil. Analysis of soil extracts with UV spectrophotometry showed that phenol,o-chlorophenol,p-chlorophenol, 2,4-dichlorophenol, 2,6-dichlorophenol and 2,4,6-trichlorophenol were rapidly degraded, whilem-chlorophenol, 3,4-dichlorophenol, 2,4,5-trichlorophenol and pentachlorophenol were degraded very slowly by microorganisms in aerobically-incubated soil at 23°C. Both 3,4,5-trichlorophenol and 2,3,4,5-tetra chlorophenol appeared to be more resistant to degradation by aerobic soil microorganisms at 23°C. None of the compounds examined were degraded by microorganisms in anaerobically-incubated soil at 23°C. Direct microscopic observation revealed that phenol and selected chlorophenols stimulated aerobic and to a lesser extent, anaerobic microbial growth in soil, and aerobic soil bacteria were responsible for the degradation of 2,4-dichlorophenol in aerobically-incubated soil at 23°C. Phenol,o-chlorophenol,m-chlorophenol,p-chlorophenol and 2,4-dichlorophenol underwent rapid non-biological degradation in sterile silica sand. Non-biological decomposition contributed, perhaps substantially, to the removal of some chlorophenols from sterile aerobically-incubated soil and both sterile and non-sterile anaerobically-incubated soil.     

Influence of cadmium,copper, and pentachlorophenol on growth and sexual development of Eisenia andrei (Oligochaeta; Annelida)

Summary In the existing guidelines for earthworm toxicity testing, mortality is the only test criterion. Mortality is, however, not a very sensitive parameter, and from an ecological point of view growth and reproduction are more important for a proper risk assessment of chemicals in soil. In this study the growth and sexual development of juvenile earthworms were considered as test criteria in a standardized earthworm toxicity test. The effect of Cd, Cu, and pentachlorophenol on the growth and sexual development of juveniles of the species Eisenia andrei was studied in an artificial soil substrate. Two tests with Cd were carried out to study the effects of the mode of application of the food source (cow dung). EC₅₀ (50% effective concentration) values for the effect of Cd, Cu and pentachlorophenol on the growth of E. andrei were 33–96, >100, and >32 mg kg^-1 dry soil, respectively, and there was no observed effect at 18–32, 56, and 32 mg kg^-1 dry soil, respectively. Sexual development of the earthworms was inhibited at 10 mg Cd kg^-1 and 100 mg Cu kg^-1 dry soil, but was not affected at the highest pentachlorophenol concentration tested (32 mg kg^-1 dry soil). The results were the same whether the food was applied in a hole in the middle of the soil or mixed homogeneously through the soil.     

Responses of Biochemical Markers in the Fish Prochilodus lineatus Exposed to a Commercial Formulation of Endosulfan

Among the most extensively used compounds for the pest control in Argentinean crops is the organochlorine endosulfan. The sublethal effects of the commercial endosulfan formulation on hematology and lipid peroxidation (LPO) of the neotropical fish Prochilodus lineatus were investigated. Firstly, we calculated acute toxicity (LC₅₀) in order to define sublethal concentrations (0, 1.2, and 2.4 ??g L^?1). Hematological and oxidative stress responses were assessed at 24, 48, and 96 h. Endosulfan exposure significantly diminished the hemoglobin concentration, mean cell hemoglobin, and total plasma protein and increased white blood cells count and plasma glucose after 96 h. Exposed fish showed an alteration of the differential leukocytes count, evidenced by more thrombocytes and monocytes and less lymphocytes and neutrophils. Endosulfan increased LPO levels in intestine, liver, and brain in both sublethal concentrations. The present results suggest that endosulfan produces biochemical and physiological alterations, including immunological disorders, and it is a good inductor of oxidative stress in P. lineatus.     

Toxic effect of landfill leachate on microalgae

Leachates from two landfills, namely Junk Bay (JB) and Gin Drinkers' Bay (GDB), were assessed for their acute toxicity using four green algal species, Chlorella pyrenoidosa, C. vulgaris, Scenedesmus sp. and Dunaliella tertiolecta. JB leachate was more toxic to the four algal species tested than leachate from GDB landfill. The growth rates of all four species in 50% JB leachate, and two species (C. vulgaris and D. tertiolecta) in 50% GDB leachate were significantly lower (P<0.05) than those in the control (Bristol Medium only). Values of 96h-EC50 of JB leachate for all four species were lower than those of GDB. The high contents of ammoniacal-nitrogen and organic compounds (such as volatile fatty acids) seemed to be the factors governing the toxicity of leachate on algae. There were differential sensitivities to leachate exhibited by the tested algal species. Susceptibility to leachates in terms of cell number were in the ascending order of C. pyrenoidosa, Scenedesmus sp., C. vulgaris and D. tertiolecta.     

Effects of Single Metals and their Mixtures on Selected Enzymes of Carcinus Maenas

In this work, the acute effects of copper, chromium and mixtures of both metals on females of the marine crab Carcinus maenas were investigated. The parameters indicative of toxicity were mortality and the activity of the enzymes acetylcholinesterase (AChE), lactate dehydrogenase (LDH) and glutathione-S-tranferases (GST). LC50 values determined at 96 hr were 51.8 mg L^-1 for copper, 49.8 mg L^-1 for chromium and 15 mg L^-1 Cu + 43.6 mg L^-1 Cr for the mixture of both metals. Copper, chromium and the mixtures of both metals significantly inhibit haemolymph AChE, ovarian LDH and hepatopancreas GST after an in vivo exposure of 96 hr to concentrations lower than NOEC values for mortality. Furthermore, the mixtures tested showed a more pronounced effect than individual agents.     

Zirconium toxicity assessment using bacteria,algae and fish assays

Our contribution to Zr environmental hazard, arrived at by means of bioassays on bacteria, microscopic algae and fish, confirms the hypothesis that Zr has low toxicity. Toxic effects revealed with the Microtox test may be attributed to pH rather than specifically to Zr (5 min. EC₅₀ > 4.3 mg L^?1). Fish assays also confirmed the low toxicity of Zr (96-hr LC₅₀ > 20 mg L^?1; 96 hr minimal stress concentration > 20 mg L^?1; Mutagenicity (Fluctuation test) and genotoxicity (S.O.S. Chromotest) assays failed to show any DNA-related effects linked to this metal. Only the algal assays (ATP energy stress) demonstrated genuine toxicity at Zr concentrations between 1.3 and 2.5 mg L^?1.     

Cyanogenic Residues: Environmental Impacts,Complexation with Humic Substances,and Possible Application as Biofertilizer

Treated and untreated rice straw extensively exists in the soil. In order to elucidate its possible effect on the fate of organic pollutants, sorption of pyrene by rice straw and its main constituents (lignin, cellulose, and hemi-cellulose) were studied, as single solute and in the presence of other co-existing organic pollutants, phenanthrene (Phen), benzo[a]pyrene (BaP), phenol, and pentachlorophenol (PCP). Pyrene showed the greatest sorption on lignin with greater aromaticity and smaller polarity, and the sorption coefficient was almost two orders of magnitude greater than those on cellulose and hemi-cellulose. Bi-solute sorption results showed that Phen, BaP and PCP exhibited apparent competitive sorption with pyrene on the four sorbents; while the existence of phenol promoted the sorption of pyrene on rice straw and lignin but inhibited the sorption on cellulose and hemi-cellulose. For the two polycyclic aromatic hydrocarbon (PAH) co-solutes and PCP, hydrophobicity and molecular size played important roles in competition, suggesting the direct competition for hydrophobic sorption sites and pore blockage mechanisms. In contrast, the polar co-solute, phenol showed different effects on pyrene sorption onto the four sorbents, suggesting that multiple interactions between polar organic compounds and sorbents are involved in the sorption.     

Effects of Water Hardness and Metal Concentration on a Freshwater Tubifex Tubifex Muller

The present investigation was designed to determine the effectsof water hardness and heavy metals concentrations on a freshwaterTubifex tubifex. Very few data concerning the effect of water hardness on the acute toxicity of heavy metals are available on T. tubifex, which has been proposed as a testorganism for ecotoxicological studies. The effect of water hardness on the toxicity of heavy metals is discussed. The acutetoxicity of selected heavy metals to a freshwater T. tubifex Muller was determined in very soft, soft, hard and veryhard (12, 45, 170 and 300 mg CaCO₃ L^-1 total hardness,respectively) water. Percentage mortality of T. tubifex as influenced by heavy metals was studied in water of variable hardness. Water hardness had a significant effect on heavy metalstoxicity. The concentrations of metals necessary to immobilize 50% of the test animals at 24, 48, 72, 96 hr were significantlydifferent in soft and hard water. The 96 hr EC₅₀ valuesfor T. tubifex were higher in hard and very hard watercompared with soft and very soft water. Median effectiveconcentrations (EC₅₀) and their 95% confidence limits weredetermined for cadmium, cobalt, chromium, copper, iron, lead, manganese, mercury, nickel, and zinc during exposure for 24, 48,72 and 96 hr in four different water hardness. Hardness has a muchsmaller effect upon the acute toxicity of mercury than the otherheavy metals tested. The results indicate that Cu, Cd, Hg and Zninduced autotomy of the caudal region and mucus production. It isconcluded that water hardness parameters should be considered inestablishing appropriate water quality criteria and standards forthe protection of aquatic fauna and flora, and ultimately human health.     

The influence of soil characteristics on the toxicity of four chemicals to the earthworm Eisenia fetida andrei (Oligochaeta)

Summary The acute toxicity of Cd (chloride), chloroacetamide, 3,4-dichloroaniline and pentachlorophenol to the earthworm Eisenia fetida andrei was determined using the OECD (1984) artificial soil and contact testing procedures. To investigate the influence of two soil characteristics (pH and organic-matter content), the toxicity of the chemicals was also determined in two natural sandy soils. It is concluded that the filter-paper contact test cannot be recommended to predict earthworm toxicity of these chemicals in soil. Toxicity in soil was influenced by both pH and organic-matter content. Differences between LC₅₀ values in the high-organic-matter artificial soil and in an acid, low-organic-matter sandy soil were, however, not greater than a factor of 3–4. The results of this study therefore support the use of a well-defined artificial soil substrate for standardized earthworm toxicity tests.     

The Influence of Water Hardness, pH, and Suspended Solids on Nickel Toxicity to Larval Fathead Minnows (Pimephales promelas)

Nickel (Ni) is an ubiquitous, naturally occurring metalthat is associated with metal mining and other industrialactivities. Despite elevated Ni concentrations reportedfor many industrial receiving waters, Ni receives littleresearch attention addressing factors influencing itstoxicity to freshwater fish. This study examined theinfluence of water hardness, pH, and total suspended solids(TSS) in soft, reconstituted water on Ni toxicity to larvalfathead minnows (Pimephales promelas). Increasingwater hardness from 20 to 140 mg L^-1 (as CaCO₃) reduced acute Ni toxicity by 5-fold (96-h LC50s 0.45 and 2.27 mg Ni L^-1, respectively). Low pH had a slight protective effect against Ni toxicity relative to neutral pH conditions. At pH 5.5, the 96-h LC50 was 0.69 mg Ni L^-1, compared to 0.54 mg Ni L^-1 at pH 7.0. However,Ni toxicity was significantly reduced at pH 8.5 where the 96-h LC50 was 2.21 mg Ni L^-1. These results were explainedon the basis of Ni speciation. Total suspended solids also reduced Ni toxicity (expressed as 96-h LC50s) from 0.35 to 1.12 mg Ni L^-1 over a TSS range of 10 to 100 mg L^-1.This reduction of toxicity due to TSS is significant becausemine effluents often have a combination of elevated TSS andmetals. The ameliorative effect of TSS was not as significantas high hardness or pH probably because there is a TSS threshold, after which physical irritation to fish gills counteracts any protective effect conferred by TSS. This finding is relevant to choices made in design of mine effluenttreatment systems; i.e., there may be an optimum range ofTSS concentrations that protect aquatic biota againsteffects of metals that remain after treatment.