Effects on Microorganisms and Plants

Effects on Microorganisms and Plants Copper is toxic to many bacteria and viruses (Stauber 1995). For example, in cultures of 

Algae may be copper-tolerant, especially if they are not polyphosphate-deficient (Stauber and Florence 1987). 

The essentiality of copper arises from its specific incorporation into a large number of enzymatic and structural proteins. The role of copper in oxidation-reduction enzyme activities is the consequence of its ability to function as an electron transfer intermediate. Thus, copper is present in enzymes involved in cellular respiration, free radical defense, neurotransmitter function, connective tissue biosynthesis, and cellular iron metabolism. 

The essentiality of copper to animals is mediated through specific copper proteins including tyrosinase, monoamine oxidase, dopamine beta-hydroxylase, ceruloplasmin, superoxide dismutase (SOD), lysyl oxidase, tryptophan 2,3-dioxygenase, and cyto- 

The addition of molybdenum to the diet of ruminants deficient in copper worsens this deficiency by enhancing biliary excretion of copper, when this is not a major copper 

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Here we will describe the methods that are used to derive critical limits for soil, based on direct ecotoxicological effects on microorganisms and plants. The indirect approaches (food web models) to derive critical limits for soil based on critical limits for terrestrial fauna such as MPC values for target organisms will be also considered. 

Waste Products and Recycling No chemotoxic or radiotoxic effects on microorganisms or plants are known from exposure to environmental radioactivity from natural and industrial sources of uranium, thorium and their decay products. 

Electrolysis has the potential advantage that a metal can be recovered in its most valuable forms as metal film or powder and sold or recycled to the process. Cf. also Walsh, Ref. [133]. Heavy metals, such as copper from metal complex dyes, or from catalysts in industrial effluents, have become a problem in clarification plants because of their toxic effects on microorganisms. Their disposal through deposition after chemical or physical treatment is senseless,... 

Environmental risk assessment examines the potential adverse effects to ecosystems from exposure of the aquatic, terrestrial and air components. Initial assessment normally focuses on the aquatic compartment, including effects on microorganisms in waste water treatment plants. This first tier risk assessment can be extended to cover the sediment part of the aquatic compartment and the soil compartment. At higher tonnage levels, effects relevant to the food chain are evaluated, i.e., secondary poisoning. Diderich in Chapter 8 of (73) discusses the principles of EU environmental risk assessment. 

Some of the processes, mentioned above occur also in soils. Microorganisms and plants produce a larger number of biogenic acids. The downward vertical displacement of Al and Fe observed in the podsolidation of soils can be accounted for by considering the effect of pH and of complex formers on both the solubility and the dissolution rates. 

McGrath, S. P., Chaudri, A. M., and Giller, K. E. (1995). Long-term effects of metals in sewage sludge on soils, microorganisms and plants. ]. Ind. Microbiol. 14, 94-104. 

Hader, D. P, Effects of enhanced solar ultraviolet radiation on aquatic ecosystems, in UV-B Radiation and Ozone Depletion Effects on Humans, Animals, Plants, Microorganisms, and Materials, Tevini, M., Ed. Lewis Publishers, Boca Raton, FL, 1993, 155. 

Sulfur oxidation produces substantial amounts of H2SO4. The resulting acidification can lead to solubilization of phosphorus and other mineral nutrients in soils with a generally beneficial effect on both microorganisms and plants. 

Several types of interactions are possible when a herbicide is introduced into the plant environment. In addition to the desired effects of the herbicide on weeds, growth alteration of crop plants may occur. It follows then that any pesticide, applied to plants or soils to control a specific pest, may also affect nontarget soil microorganisms and plants. Therefore the phenomenon of disease increase due to herbicides is not restricted to a specific group of herbicides, pathogens, or crops. 

An Environmental Impact Report is also required for a notification. This is an assessment of the environmental compatibility made by the notifier, and is based on an evaluation of degradation, accumulation and mobility in the environment, effects on microorganisms, plants, animals and ecosystems and long-term indirect effects on humans via the environment. 

As no enzyme or enzyme system has yet been identified which requires cesium for activity, it is no surprise that any adverse effects of cesium on microorganisms or plants have been reported (Burkardt and Wirth, 1986). 

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