Pesticide beneficial effects

Some of these compounds could be considered as dietary additives, but various other terms, including pesticides, can also be used. They can have beneficial effects on the environment and this aspect will be discussed later. The ionophore monensin, which is an alicyclic polyether (Figure 1), is a secondary metabolite of Streptomyces and aids the prevention of coccidiosis in poultry. Monensin is used as a growth promoter in cattle and also to decrease methane production, but it is toxic to equine animals. " Its ability to act as an ionophore is dependent on its cyclic chelating effect on metal ions. ° The hormones bovine somatotropin (BST) and porcine somatotropin (PST), both of which are polypeptides, occur naturally in lactating cattle and pigs, respectively, but can also be produced synthetically using recombinant DNA methods and administered to such animals in order to increase milk yields and lean meat production. "... 

All decisions involve tradeoffs. Does the benefit of increased food product ion outweigh possible health risks of a pesticide Do the beneficial effects of a new drug outweigh a potentially dangerous side effect in a small fraction of users The answers are rarely obvious, but we should at least try to base our responses on facts. 

But wait. Let s remember that chemicals have virtually transformed the modern world in extraordinarily beneficial ways. During the past 100 years the chemical industry has offered up, and we have eagerly consumed, thousands of highly useful materials and products. Among these products are many that have had profoundly beneficial effects on human health - antibiotics and other remarkable medicinal agents to prevent and cure diseases, pesticides to protect crops, preservatives to protect the food supply, plastics, fibers, metals and hundreds of other materials that have enhanced the safety and pleasures of modern... 

The water data plotted in Figures 3-16 showed that most of the pesticides are sorbed on soil particles. This confirmed what is probably the most beneficial effect of soil in the containers it guaranteed almost complete containment even when the liquid contents were lost. 

Among them are carbon monoxide, cyanide, benzopyrene, and tar, the same toxic chemicals present in cigarette smoke. (Some researchers feel that any beneficial effects that may be found in the medicinal use of marijuana are actually negated by the current lack of a suitable alternative delivery method.) Additionally, any pesticides sprayed on the plant by the grower are present in the smoke, and are inhaled along with the THC. 

Although the beneficial effects of many organic halides are undisputed, certain synthetic chlorinated organics such as the chlorofluorocarbons and the pesticide DDT have caused lasting harm to the environment. 

For a cholinergic neuron to receive another impulse, acetylcholine must be released from the receptor to which it has bound. This will only happen if the concentration of acetylcholine in the synaptic cleft is very low. Low synaptic concentrations of acetylcholine can be maintained via a hydrolysis reaction catalyzed by the enzyme acetylcholinesterase. This enzyme hydrolyzes acetylcholine into acetic acid and choline. If acetylcholinesterase activity is inhibited, the synaptic concentration of acetylcholine will remain higher than normal. If this inhibition is irreversible, as in the case of exposure to many nerve gases and some pesticides, sweating, bronchial constriction, convulsions, paralysis, and possibly death can occur. Although irreversible inhibition is dangerous, beneficial effects may be derived from transient (reversible) inhibition. Drugs that inhibit acetylcholinesterase in a... 

Although it is rather difficult to evaluate the positive effects of pesticides for the period of their application, it is even more complicated to evaluate their negative effects on the environment. The beneficial effects are well documented. In the case of the most frequently discussed preparation, DDT (for the discovery of biological application of DDT P. H. Muller was awarded the Nobel Prize for physiology and medicine in 1948), it is estimated today that in the first 10 years of its application, DDT saved lives of millions of people. Furthermore, hundreds of millions of people have been protected from malaria, typhoid fever, dysentery and more than twenty million people from diseases caused by insects and arthropods. 

Thus, evidence that subtle and adverse changes in behavior of rats persist beyond exposure to these pesticides is mixed, and when effects occur, they appear to depend on the OP tested. Beneficial effects on conditioned behaviors have also been reported. The question of whether prior poisoning is necessary for persistent effects remains open because the only rats in the Samsam et al. (2005) study that exhibited persistent effects had been exposed both chronically and to high-level doses of chlorpyrifos that elicited acute signs of poisoning, whereas Sanchez-Santed ei al. (2004) observed persistent effects in rats that had not exhibited acute toxicity during treatment. 

Although the use of pesticides has become indispensable due to their beneficial effect on crop yield, forest protection, and domestic living, their potential threat to the... 

The Environmental Protection Agency regulates the use of pesticides in such a way that they are permitted for use when the beneficial effects are deemed to outweigh the risks that may occur to man and his environment on use of those pesticides. Thus, in regulating pesticides, the EPA resorts to benefit and risk analysis as pertains to specific pesticides and specific uses of pesticides. 

I think the effects of a pesticide which are generally considered beneficial are, for example, its effect on the cost of agricultural products. A new pesticide may decrease the cost of production of a food or fiber product. Therefore it should be considered beneficial for that reason. Likewise, the elimination of the use of an old pesticide may increase the cost of the food or fiber. Use of pesticides may provide increased recreational opportunities. Elimination or control of human disease organism would of course be considered a benefit. Likewise, the elimination or control of unwanted animals or plants would also be considered a beneficial effect of pesticides. 

An alternative hypothesis to account for the beneficial effects of bentonite could be that this treatment was promoting metabolism of T-2 to less active higher metabolites. Chadwick et al. C1978) have reported that dietary fibre can promote the metabolism of pesticides even though the polymeric fibres cannot be absorbed from the gastrointestinal tract. 

So, should we still use atrazine All decisions involve tradeoffs, and the answer is rarely obvious. Does the benefit of increased food production outweigh possible health risks of a pesticide Do the beneficial effects of a new drug outweigh a potentially dangerous side effect in a small number of users Different people will have different opinions, but an honest evaluation of facts is surely the best way to start. At present, atrazine is approved for continued use in the United States because the EPA believes that the benefits of increased food production outweigh possible health risks. At the same time, though, the use of atrazine is being phased out in Europe. 

It is very clear, therefore, that there have been many examples of neurotoxic effects, both lethal and sublethal, caused by pesticides in the field over a long period of time. Far less clear, despite certain well-documented cases, is to what extent these effects, especially sublethal ones, have had consequent effects at the population level and above. Interest in this question remains because neurotoxic pesticides such as pyre-throids, neonicotinoids, OPs, and carbamates continue to be used, and questions continue to be asked about their side effects, for example, on fish (Sandahl et al. 2005), and on bees and other beneficial insects (see, for example, Barnett et al. 2007). 

Sinclair, R. G., Slow-release pesticide system polymers of lactic and glycolic acids as ecologically beneficial, cost-effective encapsulating materials. Environ. Sci. Technol., 7, 955, 1973. 

Piorr H P (1992), Phytopathological advantages and risks of organic farming systems Future perspectives to improve organic cropping systems , in Altman J, Pesticide-interactions in Crop Production Beneficial and deleterious effects, CRC Press, Cleveland, 461 172. 

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