In utero domoic acid toxicity: a fetal basis to adult disease in the California sea lion (Zalophus californianus)

California sea lions have been a repeated subject of investigation for early life toxicity, which has been documented to occur with increasing frequency from late February through mid-May in association with organochlorine (PCB and DDT) poisoning and infectious disease in the 1970's and domoic acid poisoning in the last decade. The mass early life mortality events result from the concentrated breeding grounds and synchronization of reproduction over a 28 day post partum estrus cycle and 11 month in utero phase. This physiological synchronization is triggered by a decreasing photoperiod of 11.48 h/day that occurs approximately 90 days after conception at the major California breeding grounds. The photoperiod trigger activates implantation of embryos to proceed with development for the next 242 days until birth. Embryonic diapause is a selectable trait thought to optimize timing for food utilization and male migratory patterns; yet from the toxicological perspective presented here also serves to synchronize developmental toxicity of pulsed environmental events such as domoic acid poisoning. Research studies in laboratory animals have defined age-dependent neurotoxic effects during development and windows of susceptibility to domoic acid exposure. This review will evaluate experimental domoic acid neurotoxicity in developing rodents and, aided by comparative allometric projections, will analyze potential prenatal toxicity and exposure susceptibility in the California sea lion. This analysis should provide a useful tool to forecast fetal toxicity and understand the impact of fetal toxicity on adult disease of the California sea lion.

Toxicity of phenyl-mercuric lactate for fish

Phenyl-mercuric lactate is included in the pulp processing reagents by some paper mills to eliminate slime formation in the pulp. Small quantities of this chemical are added to the wet pulp in the beaters, particularly for the bactericidal action against Aerobacter aerogenes. Subsequently the mecurial is carried away in the wash waters. However, as the highly poisonous nature of many compounds of mercury is well known, questions have been raised concerning the pollution hazards created by phenyl-mercuric lactate in streams receiving effluents from mills using this substance.

Biochemical variation during ovarian vitellogenic growth in a hill stream teleost Garra mullya (Sykes) due to cadmium toxicity

Some biochemical variations during ovarian vitellogenic growth in hill-stream teleost Garra mullya due to sublethal concentration of cadmium has been discussed. Total protein, cholesterol and glycogen in ovary and liver along with gonadosomatic index (GSI) and hepatosomatic index (HSI) in Cd-treated fish exhibited significant decrease while liver glycogen remained unaltered.

Toxicity of methyl amine on Catla catla (Ham) fingerlings

The toxicity of methyl amine was studied by finding out its LC 50 values for Catla catla fingerlings. On the basis of LC 50 values, the harmless concentration of methyl amine was found to be 12.8 ppm. This indicates that methyl amine is fairly toxic to C. catla fingerlings and needs care for its disposal in aquatic environment.

Preliminary trials on the toxicity of "Algistat" to fish and algae

Preliminary toxicity trials conducted with "Algistat" (an algicide) indicated that a dose of 0,66ppm of the compound was highly toxic to fish and 0.8ppm was the general lethal level for Spirogyra sp. The blue green algae, Oscillatoria sp., Mycrocystis sp. and Anabaena sp. were adversely affected by dosages higher than 0.5 ppm Euglena sp. was not affected even at 1.0 ppm.

Toxicity of four therapeutic compounds to fry of Indian major carps

Toxicity of four therapeutic compounds: sodium chloride, potassium permanganate, potassium dichromate and acriflavine to fry of Catla calla, Labeo rohita and Cirrhinus mrigala was tested. Bioassays were conducted in 5 and 10 liters glass jars in the laboratory for periods of 24-48 hrs. at temperatures of 26° and 32°C. LC 50 values of the chemicals were in the ranges of 5500 to 7500 ppm, 37.5 to 48 ppm, 92.5 to 125 ppm and 47.5 to 80 ppm respectively. The results obtained are of value in evolving cheap control methods against some common fish diseases. Sodium chloride and acriflavine can be widely used for chemotherapy and potassium dichromate is preferable to potassium permanganate for prophylaxis.

Toxicity of malathion to silver barb (Barbodes gonionotus Bleeker) fingerlings

Static bioassays were performed to observe the toxic effect of malathion to Barbodes gonionotus at 0.0 to 20.0 ppm concentrations. Malathion at 5.0 ppm was harmless to B. gonionotus and concentrations above 6.0 ppm were found to be lethal. Malathion at 2.06 ppm was safe for the B. gonionotus.

Acute toxicity of chlorpyrifos, cadusafos and diazinon to three Indian major carps (Catla catla, Labeo rohita and Cirrhinus mrigala) fingerlings

Fingerlings of three Indian major carps, viz. Catla catla (Hamilton-Buchanon), Labeo rohita (Hamilton-Buchanon) and Cirrhinus mrigala (Hamilton-Buchanon), were exposed to different concentrations of chlorpyrifos (lorsban 10 G), cadusafos (rugby 10 G) and diazinon (basudin 10 G) for a period of 96h with a view to determine the median lethal concentrations (LC sub50) values for each of chemicals. Of the tested concentrations, chlorpyrifos at a dose of 6.65 ppm, cadusafos at 2.0 ppm and diazinon at a dose of 8.40 ppm or above induced 100% mortalities within 96h of exposure. The 96h LC sub50 values of chlorpyrefos, cadusafos and diazinon were 1.66, 0.72 and 2.10 ppm for C. catla, 2.35, 0.72 and 2.97 for L. rohita and 2.35, 0.72 and 2.10 ppm for C. mrigala, respectively. Pesticide induced behavioral abnormalities observed in the present study included erratic movements, rapid operculum activities, jumping of fish out of the test media, violent spasm and convulsion.

Toxicity of copper sulphate on some haematological parameters of a freshwater teleost Cyprinus carpio var. communis

Haematological changes in a freshwater teleost, Cyprinus carpio var. communis, exposed to acute and sublethal toxicity of copper sulphate were studied. During the acute treatment, erythrocyte and leucocyte count, and haemoglobin content increased, whereas during the sublethal treatment, erythrocyte count and haemoglobin content decreased and leucocyte count increased.

Responses of plasma transaminase activity in Cyprinus carpio var. communis to mercury toxicity

The present study reports the behavioural and enzymological responses in a freshwater teleost fish, Cyprinus carpio var. communis, exposed to acute and sublethal toxicities of mercuric chloride. During acute treatment, significant behavioural changes like erratic swimming, excess mucus secretion and increased opercular movements were noticed. During acute and sublethal treatments, both aspartate amino transferase and alanine amino transferase activity increased throughout the study period. Comparing the treatments, the changes in enzyme activities were found high in acute treatment and all the values were significant at 5% level. The above findings can be used as non-specific biomarkers of environmental pollutants.

Effect of some environmental factors on the acute toxicity of deltamethrin to common carp: a laboratory study under aerobic condition

The toxicity of xenobiotic in aquatic ecosystems is influenced by many factors such as ambient temperature, water hardness, pond soil type, etc. In the present study, it was observed that air temperature, water hardness and soil sediment have profound influence on the toxicity of deltamethrin to common carp fry (ay. length 3.5 ± 0.5 cm, ay. weight 0.58 ± 0.25 g); 96h LC(sub)50 values for common carp at 38.07 ± 2.20°C maximum and 27.86 ± 1.22°C minimum air temperature in soft and very hard water were 0.102 and 0.495 µg lˉ¹, respectively. This value had increased significantly to 2.37 and 3.02 µg at 30.55 ± 1.21°C maximum and 26.04 ± 0.61°C minimum air temperature, respectively. When sediment was included, 96h LC(sub)50 at 38.07°C maximum temperature in very hard water was 1.808 µg 1ˉ¹ and this had increased to 8.073 µg 1ˉ¹ when tested at 30.55°C maximum temperature. Due to the 7.5°C increase in maximum and 1.7°C in minimum temperature, toxicity increased significantly. Lower toxicity in very hard water in comparison to soft water may be due to the lower solubility of deltarnethrin and high level of calcium. Adsorption reaction of deltamethrin with clay, humus, FeOOH, MnOOH and particulate organic carbon, and complexation reaction with dissolved organic carbon were responsible for the lowered toxicity in the experiment with sediment. Exposure time had no significant effect on acute toxicity of deltamethrin.

Influence of some abiotic factors on the acute toxicity of cadmium to Cyprinus carpio

Hardness of water had significant effect on the acute toxicity of cadmium to common carp, Cyprinus carpio. The 96h LC sub(50) and safe application rate increased from 43.17 and 22.77 mg 1 super(-1) in soft water (0.9 mM Ca super(2+) l super(-1)) to 310.48 and 177.66 mg l super(-1), respectively, in very hard water (6.0 mM Ca super(2+) l super(-1)). In medium hard and hard water, 96h LC sub(50) values were 48.39 and 116.45 mg l super(-1). When sediments were included in the medium hard, hard and very hard water treatments, the 96h LC sub(50) were 111.20, 133.71 and 334.47 mg l super(-1), respectively. Among these values, the one for medium hard water with sediment treatment was significantly higher than medium hard water treatment; values for the other two treatments were non-significant when compared with respective water treatments. Sediment was able to reduce the acute toxicity of cadmium mainly due to the complexation of cadmium with dissolved organic carbon (DOC). At the lower hardness level, cadmium complexed with DOC and the acute toxicity was reduced significantly. At higher hardness, most of the DOC sites were occupied by calcium and the acute toxicity of cadmium was not significantly reduced in hard water with sediment and very hard water with sediment experiments in comparison to respective water treatments.

Effect of Neemta 2100 toxicity on acetylcholinesterase and serum glutamate oxaloacetate transaminase enzymes in serum of fish, Oreochromis mossambicus

Acetylcholinesterase and serum glutamate oxaloacetate transaminase enzymes have been used as marker monitoring the effect of neem seed based pesticide Neemta 2100 on the fish, Oreochromis mossambicus. Fishes exposed to sublethal concentrations of Neemta 2100 for acute periods of 24 and 48 hours were sacrificed to determine enzyme activities in serum affected due to toxicity. Laboratory studies of in vivo exposure of this pesticide showed synergistic inhibitory effect during acute period of toxicity. Acetylcholinesterase was noticed as 6.25 µm substrate hydrolyzed/mg protein/hour and serum glutamate oxaloacetate transaminase was noticed as 36.71 µm substrate hydrolyzed/mg protein/hour in control fish serum. Significant decrease in GOT level in Neemta 2100 treated fishes after short term exposure indicated its severe toxicity to fish.

Acute toxicity of four heavy metals to Sphaeroma walkeri and Ciroiana bovina (Crustacea:Isopoda)

The median lethal concentrations (LC50) of two Isopoda species exposed to each tested metal (Cu. Co, Cd and Zn) in static tests for different exposure periods are quite variable depending on the tested metal The LC50 values for Sphaeroma walkeri after 24 hours exposure to Cu and Co were estimated graphically to be 11.20 and 7.00 mg/1 respectively. The correspoding values for Cirolana bovina exposed to Cu, Co, Cd and Zn were 3.60, 11.0, 3.80 and 4.80 mg/1 respectively. For 2 days the LC50 of S. walkeri exposed to Cd was 5.60 mg/l, but it was 10.10 mg/l for 3 days exposure to Zn. After prolonged exposure the LC50 values decreased proportionally with the exposure duration of the test the percentages of surviving animals demonstrated a progressive decrease with increasing concentratins as a main factor from the analysis of variance (ANOV A). The sensitivity of adult S. walkeri exposed to the four heavy metals for different exposure times ranked: Cd>Co>Zn>Cu. Cirolana bovina appeared to be more sensitive to Cu. Cd and Zn than to Co. Species in order of increasing sensitivity is C. bovina more than S. walker.

Acute toxicity of beta gamma-CAT, a naturally existing non-lens beta gamma-crystallin and trefoil factor complex from frog Bombina maxima skin secretions

In vertebrates, non-lens beta gamma-crystallins are widely expressed in various tissues, but their functions are unknown. The molecular mechanisms of trefoil factors, initiators of mucosal healing and being greatly involved in tumorigenesis, have remained