In this paper, tests and standards on assessing smoke toxicity of materials will be reviewed first. Toxic potency data such as EC50, LC50, IC50, LT50 and IT50 are briefly introduced and criticized for suitability to use. Whether LC50 is a good toxic potency parameter will be discussed. Preliminary tests on some of these toxic data for selected building materials commonly used will be assessed. ...

Nineteen adjuvants, many used as surfactants for aquatic herbicide applications, were applied in static bioassay to bluegill sunfish (Lepomis macrochirus) for 96 h to determine median lethal concentrations (LC50). Surfactants are added to the tank mix as a percentage (v/v) of the total volume, in contrast to herbicide application rates, which are usually expressed in kilograms per hectare. Two ...

Two novel crystal protein genes, cry30Ba and cry44Aa, were cloned from Bacillus thuringiensis subsp. entomocidus INA288 and expressed in an acrystalliferous strain. Cry44Aa crystals were highly toxic to second-instar Culex pipiens pallens (50% mortality concentration [LC50] = 6 ng/ml) and Aedes aegypti (LC50 = 12 ng/ml); however, Cry30Ba crystals were not toxic.

The rare earth metals cerium, lanthanum, and neodymium each were evaluated in an in vitro cytotoxicity assay system using adult, male Sprague-Dawley rat pulmonary alveolar macrophages. Both the soluble chloride form of these metals and their insoluble metal oxides were studied. For comparison purposes, the cytotoxicities of cadmium chloride and cadmium oxide were also quantified in this test sy...

OBJECTIVE Evaluating the larvicidal activity of two ether factions from Asteraceae (the aster, daisy or sunflower family, i.e. Heli opsisoppositifolia (L.) Druce (oxeye, sunflower-like) and Jaegeria hirta (Lag.) Less (weed-like)) on Aedes (Stegomyia) aegypti (L.) final third instar or initial fourth instar larvae near the town of Armenia in the Quindío Department in Colombia. METHODS H. oppos...

recently, some natural products have been used in the fields as alternative to synthetic compounds, to minimize the negative impacts to the environment. this study aimed to verify the effects of neem-based bio-pesticide in causing acute toxicity for a fish and chronic toxicity for a microcrustacean. to this end, danio rerio and daphnia magna were exposed to various concentrations of a neem-base...

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...

BACKGROUND & OBJECTIVES Mosquitoes transmit serious human health diseases, causing millions of deaths every year. Plants may be sources of alternative mosquito control agents. The present study was carried out to assess the role of larvicidal activities of the crude extracts of four plants viz. Alternanthera sessilis L. (Amaranthaceae), Trema orientalis L. (Cannabaceae), Gardenia carinata Smith...

Rainbow trout (Oncorhynchus mykiss) and yellow perch (Perca flavescens) have a different sensitivity to cadmium (Cd) in vivo (trout < LC50 < perch). Metals and particularly Cd impair cortisol secretion by adrenocortical cells in both species. The purpose of the present study was to assess in vitro the effect of Cd on cortisol secretion by adrenocortical cells of trout and perch, to compare the ...