The median 96-h lethal zinc concentration (LC50) was 439 microg Zn/L (hardness of 154 mg/L as CaCO3) for feral mottled sculpin (Cottus bairdi), decreasing to a median incipient lethal level of 266 microg Zn/L after 13 d. The 30-d chronic value was 255 microg Zn/L. The acute toxicity-hardness (ln-ln) slope of 1.022 exceeded that of the current U.S. Environmental Protection Agency zinc criteria. ...

This study was carried out on fish channa punctatus to investigate the lethal concentration of cadmium nitrate at 24 hr. Experiment procedure repeated five times selected concentrations, noting number killed. The mean value taken. These values were taken determine LC50 for Toxicity heavy metals it may be depends upon dose and time exposure period.

Buprofezin is an insect growth regulator and widely used insecticide in Malaysia. The present study evaluated the toxic effects of buprofezin on the embryo and larvae of African catfish (Clarias gariepinus) as a model organism. The embryos and larvae were exposed to 7 different concentrations (0, 0.05, 0.5, 5, 25, 50 and 100 mg/L) of buprofezin. Each concentration was assessed in five replicate...

Two new dimeric epipolythiodiketopiperazines, preussiadins A (1) and B (2), together with two known diastereomers, leptosins C (6) and A (7), were obtained from the mycelia of a Preussia typharum isolate. The structures of the new compounds were established by spectroscopic methods, and the absolute configurations of 1 and 2 were assigned by chemical transformations and comparisons of quantum c...

DDT (Dichloro-diphenyl-trichloroethane) and chlordane are the organochlorine pesticides (OCPs) dangerous to human health easily accumulate in biological tissues, used control insects crops, livestock house protection. This study aimed evaluate toxicity of DDT, cis (alpha-chlordane), trans (gamma-chlordane) on growth two crustaceans species Daphnia magna (D. magna) Moina macrocopa (M. macrocopa)...

numerous studies have been focused on natural anticarcinogenic agents. many antioxidants have been identified as anticarcinogens. antimutagens have also been proposed as cancer chemopreventive agents. the use of natural products as anticancer has a long history that began with traditional medicine. the aim of this study was to evaluate cytotoxicity and antioxidant activity of twenty-three plant...

Assessment of contaminant impacts to federally identified endangered, threatened and candidate, and state-identified endangered species (collectively referred to as "listed" species) requires understanding of a species' sensitivities to particular chemicals. The most direct approach would be to determine the sensitivity of a listed species to a particular contaminant or perturbation. An indirec...

Cadmium, a metal widely used in industrial processes, has been recognized to be a highly toxic and dangerous environmental pollutant. These excess amounts in addition to naturally occurring levels gradually build up to toxic levels causing damages to the biota of the aquatic ecosystem. The fresh water field crab, Paratelphusa hydrodromous is an important human food source in parts of South Indi...

No-effect concentration as well as safe concentration of mercury was evaluated by exposing Perna viridis and Mugil cephalus to 24-hour static renewal bioassay for 96-hours. The 96-hour LC50 value was 75 and 129 μg/l Hg for Mugil cephalus and Perna viridis. Juvenile mullets were more sensitive than green mussel. The safe concentration calculated were 0.75 and 1.29 μg/l Hg. The no-effect concentr...