1. Using the loss of turgidity of the cells as a criterion it is found that the toxicity curve of copper chloride with Nitella is sigmoid. An empirical equation can be constructed which will approximately fit the curve. 2. When the concentration of the copper chloride is varied the toxic effect varies as a constant, fractional, power of the concentration. This relation holds when the concentrat...

in this research, the batch removal of toxic hexavalent chromium ions from wastewater and aqueous solution using dried (bd) sargassum sp. (brown marine algae) and activated carbon (ac) prepared from it was examined. biomass, ph and the initial concentration of cr(vi), adsorption models and kinetic studies were investigated. the experiment was performed in a batch system and theeffect of solutio...

the contamination of water by toxic heavy metals is a world-wide environmental problem. discharges containing cadmium, in particular, are strictly controlled due to the highly toxic nature of this element and its tendency to accumulate in the tissues of living organisms. low concentration (below 5 mg`/l) of cadmium is difficult to treat economically using chemical precipitation methodologies. i...

The incidence of putatively toxic serum concentrations and the factors influencing their occurrence were investigated in a study of 91 neonates receiving parenteral gentamicin twice daily at a dose of mean (SD) 5.5 (0.1) mg/kg/day. Most neonates were preterm and of low birthweight. Serum concentrations, area under the curve (AUC), and clearance were calculated. Potentially toxic trough concentr...

The authors developed a simple screening-level model of exposure of aquatic species to pyrethroid insecticides for the lower American River watershed (California, USA). The model incorporated both empirically derived washoff functions based on existing, small-scale precipitation simulations and empirical data on pyrethroid insecticide use and watershed properties for Sacramento County, Californ...

Insecticides are chemicals used to kill insects, so it is unsurprising that many insecticides have the potential to harm honey bees (Apis mellifera). However, bees are exposed to a great variety of other potentially toxic chemicals, including flavonoids and alkaloids that are produced by plants; mycotoxins produced by fungi; antimicrobials and acaricides that are introduced by beekeepers; and f...

Chlorodibenzo-p-dioxins, especially 2,3,7,8tetrachlorodibenzo-p-dioxin (TCDD), are among the most toxic compounds known. These compounds are found as contaminants of technical chlorophenols and their derivatives. A variety of pathologic condition have been associated with the injestion of products containing chlorodibenzo-p-dioxins. Toxic fat, the cause of chick edema disease (1, 2) and a varie...

Identification of endogenous toxins and characterization of the mechanisms by which toxins produce cell injury and death may help understand both normal modeling of cell populations and connections in the CNS as well as abnormal cell loss. The toxicity of catecholamines intrinsic to the CNS was investigated using the model system of rat cerebral cortex in dissociated cell culture. All catechola...

Although heavy metal ions are known to be toxic to the central nervous system (CNS), the mechanisms by which the CNS may protect itself from initial challenges of such toxic ions is unknown. The choroid plexus is the principal site of formation of the cerebrospinal fluid (CSF) which bathes the brain. We have determined in rats and rabbits that after intraperitoneal administration of lead, cadmi...

The primary objective of the current study was the investigation of the influence of zinc asparaginate supplementation for 7 and 14 days on toxic metal and metalloid content in rat organs and tissues. Rats obtained zinc asparaginate in doses of 5 and 15 mg/kg/day for 7 and 14 days. At the end of the experiment rat tissues and organs (liver, kidney, heart, m. gastrocnemius, serum, and hair) were...