Biological Effects and Toxicity

The abundance of HA derivatives in plants and living organisms, either as normal metabolic intermediates or as products of detoxification, together with their reported biological effects and toxicity " , suggest that this class of compounds is likely to interact with a wide spectrum of enzymes and receptors, as either substrates, inhibitors or activators. Table 1 summarizes data on the interaction of HA and its derivatives with enzymes. 

Deaths of target organisms associated with intentional pesticide applications to insect-infested crops, weed-choked roadsides, and nematode-laced fields are predictable, desirable, and relatively easy to measure. Likewise, catastropic releases of chlorine from ruptured tank cars or of crude oil from scuttled supertankers may produce a spectrum of biological effects including toxicity. These events are easily associated with exposures to toxic substances and particular environmental circumstances. 

While some metals are nutritionally important, there is another group with no beneficial biological effects and in some cases serious toxic effects. Our complex relationship with metals is well illustrated by lead, which we have used for a variety of purposes since ancient times. In the last hundred years, lead was extensively used in paint and as a gasoline fuel additive. In the last 30 years, it was recognized... 

Biological Effects and the Concept of 2,3,7,8-TCDD Toxic Equivalency... 

Biomarkers of early biological effects and defence provide information on biological disturbance or changes that do not necessarily translate into toxic... 

The crux lies in fulfillment of the third criterion since, in natural ecosystems, biota are seldom exposed to only a single potential toxicant. This whole issue of association between biological effects and putative causes is discussed again in Chapter 7, Section 7.7.2. 

Defining a general mechanism of toxicity for creosotes, coal tar, coal tar pitch, and coal tar pitch volatiles is essentially impossible because of their diversity and variability in biological effect and composition. 

This book focuses on the chemical persistence and ocotoxicological behavior of pesticides In soil, water, and plants. Recent research data are presented on transport, adsorption and absorption, accumulation, degradation, biological effects, aquatic toxicity, air pollution, exposure, and risk estimation. 

Chapman, P.M. et al. (1982) Survey of Biological Effects of Toxicants upon Puget Sound Biota. I. Broad Scale Toxicity Suxrvey. NOAA Techn. Mem. OMPA-25, 98 pp. Boulder/CO United States Natl. Oceanic and Athmospheric Administration. 

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