Effects on Plants, Animals and Humans

There are considerable differences in the tolerance of various plant species to lithium and in their ability to take up this element, which may be related to biological barriers in root tissues. Solanaceae are known to have the highest tolerance to lithium and can accumulate more than 1000 mg kg leaf dry matter by contrast, citrus trees are 

Lithium must rather be considered as a potentially phytotoxic substance, with marked species-dependent differences in sensitivity. Even very small quantihes of lithium ions in the nutrient solution can rapidly manifest themselves in leaf chlorosis (Bach 

as lithium affects chlorophyll content, photosynthesis, respiration and various other metabolic pathways. Injury-related changes may involve cellular processes as well as the whole plant, and the effects seem to depend both on the lithium concentration and on the genetics of the plant under consideration. It may be assumed that lithium affects various plant systems, initially at the membrane level and subsequently at the metabolic level, and this results in a complexity of reactions. Lithium can have both a specific effect due to its physical-chemical properties, and a nonspecific effect which is based on its similarity to other monovalent cations. This explains why lithium may cause both positive and nega- 

In addition, and as in humans, there seems to be a narrow range of beneficial actions in plants (Schafer 1997). 

The effects of lithium on the immune system appear to have a biphasic nature, similar to the actions of lithium on mania and depression. In some circumstances, lithium may activate immune functions, while in others it may damp down excessive immunological reactions. Evidently, lithium 

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Pollution issues became significantly more important, however, with the Industrial Revolution the early 18th century. At that time, the by-products of industrial operations were released into the surrounding environment, with little or no attempt to determine or control their effect on plants, animals, and human life. One can hardly think of Great Britain at the height of its imperial powers without remembering the huge clouds of smoke and fumes that continuously... 

The recognition in the early part of the twentieth century that certain mineral elements in small concentrations had observable effects on plant, animal and human well-being has led a host of investigators to try to measure these effects quantitatively. 

The chemical control of insect pests dates back thousands of years. The earliest insecticides were inorganic compounds of copper, lead, and arsenic, as well as some naturally occurring organic compounds such as nicotine (Fig. 7.30a). Few of these first-generation insecticides are in use today because of their adverse side effects on plants, animals, and humans. 

Effects on Plants, Animals, and Humans Tab. 22.1 No rmal thallium concentrations in human body fluids and tissue... 

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