This article reviews the sources of exposure and health effects of common toxicants encountered by patients in primary care practice. The recognition and management of exposure to indoor and outdoor pollutants, heavy metals, pesticides, electromagnetic fields, and endocrine-disrupting chemicals are listed. A sample environmental history form is included.

This paper examines and evaluates the use of strychnine baits and cyanide guns for coyote (Canis latrans) control by livestock producers in Alberta. Livestock predation occurred almost exclusively during spring, summer, and fall; livestock predation was negligible during winter. In contrast, use of toxicants was negligible in spring, distributed rather evenly through the summer and fall, and mo...

Among protozoa, Tetrahymena pyriformis is the most commonly ciliated model used for laboratory research. All living organisms need to adapt to ever changing adverse conditions in order to survive. This article focuses on the phenomenon that exposure to toxic doses of the toxicants protects against a normally harmful dose of the same stressor. This first encounter by toxicant provokes the phenom...

Tropical seagrasses are at their highest risk of exposure to photosystem II (PSII) herbicides when elevated rainfall and runoff from farms transports these toxicants into coastal habitats during summer, coinciding with periods of elevated temperature. PSII herbicides, such as diuron, can increase the sensitivity of corals to thermal stress, but little is known of the potential for herbicides to...

the modeling investigation in this paper discusses the system level effects of a toxicant on a three species food chain system. in the models, we have assumed that the presence of top predator reduces the predatory ability of the intermediate predator. the stability analysis of the models is carried out and the sufficient conditions for the existence and extinction of the populations under the ...

In this paper, a nonlinear mathematical model is proposed and analyzed to study the effect of an intermediate toxic product on the growth of plant biomass. It is assumed that the toxicant uptaken by plant biomass interacts with water (sap) present in it and forms an intermediate product, which then affects the biomass. To model the phenomena, it is further assumed that the intermediate product ...

Metal toxicokinetics in invertebrates are usually described by one-compartment first-order kinetic model. Although the model gives an adequate description of the toxicokinetics in certain cases, it has been shown to fail in some situations. It also does not seem acceptable on purely theoretical grounds as accumulation and excretion rates may change depending on instantaneous toxicant concentrat...

Environmental risk assessment of contaminants is conventionally based on toxic effects assessed in organism-level test systems. We suggest that, for the prediction of toxicant effects, population- and community-level effects should be considered. The aim of this study was to investigate how predation could alter a prey population's response to a toxicant to reveal effects at population and comm...

Toxicity of the organophosphate, diazinon was studied in grass carp (Cetenopharyngodon idella) weighing 5±1.0g, under static water quality condition at 16°C. Also, some hematological and biochemical variables of fish weighing 50±5.0g were studied 12 hours post-exposing fish to the toxicant at sublethal concentration of 5.6mg/L at 16°C. Values of 18.19, 17.21, 16.68, and 15...

While risk assessment models attempt to predict human risk to toxicant exposure, in many cases these models cannot account for the wide variety of human responses. This review addresses several primary sources of heterogeneity that may affect individual responses to drug or toxicant exposure. Consideration was given to genetic polymorphisms, age-related factors during development and senescence...