Pesticides resistance

Thijssen, H.H.W. (1995). Warfarin-based rodenticides mode of action and mechanism of resistance. Pesticide Science 43, 73-7S. 

Combustion in an incinerator is the only practical way to deal with many waste streams.This is particularly true of solid and concentrated wastes and toxic wastes such as those containing halogenated hydrocarbons, pesticides, herbicides, etc. Many of the toxic substances encountered resist biological degradation and persist in the natural environment for a long period of time. Unless they are in dilute aqueous solution, the most effective treatment is usually incineration. 

Chemical, cultural, and mechanical weed control practices have been relatively successful ia reducing yield losses from weeds (448). However, herbicide-resistant weed populations, soil erosion, pesticide persistence ia the environment, and other problems associated with technologies used (ca 1993) to control weeds have raised concerns for the long-term efficacy and sustainability of herbicide-dependent crop production practices (449). These concerns, coupled with ever-increasing demands for food and fiber, contribute to the need for innovative weed management strategies (450). 

G. P. Georghiou and T. Saito, eds.. Pest Resistance to Pesticides, Plenum Press, New York, 1984. 

National Academy of Sciences, Pesticide Resistance Strategies and Tactics for Management, Washiagton, D.C., 1986. 

R. T. Roush and B. E. Tabashnik, eds.. Pesticide Resistance in Arthropods, Chapman Hall, New York, 1990. 

G. P. Georghiou and A. Lagunes-Tejeda, The Occurrence of Resistance to Pesticides in Arthropods, FAO, Rome, 1991. 

Acetophenone can react with formaldehyde to yield light-resistant resins which are used as additives in nitrocellulose paints. It is also used as a photoinitiator, and in the pharmaceuticals, perfumery, and pesticide industries (344). It can be hydrogenated to 1-phenylethanol which is used for the production of aromatic ester fragrances (345). Technical-grade acetophenone is available at 2.29/kg perfume-grade acetophenone was 6.50/kg in October 1994. 

Aerobic, Anaerobic, and Combined Systems. The vast majority of in situ bioremediations ate conducted under aerobic conditions because most organics can be degraded aerobically and more rapidly than under anaerobic conditions. Some synthetic chemicals are highly resistant to aerobic biodegradation, such as highly oxidized, chlorinated hydrocarbons and polynuclear aromatic hydrocarbons (PAHs). Examples of such compounds are tetrachloroethylene, TCE, benzo(a)pyrene [50-32-8] PCBs, and pesticides. 

Unfortunately, there is a significant disadvantage resulting from appHcation of insect-resist agents from dyebaths it is impossible to ensure 100% exhaustion (transfer of pesticide from dyebath to fiber) and as a result, there is inevitably some environmental contamination. The extent of concern with this release of insect-resist agent depends on the spectmm of activity of the agent. If it is a broad-spectmm insecticide, especially one with reasonable persistence and lipophilic character, it is Hable to be reasonably toxic to aquatic insects and invertebrates, especially in certain environmental locations where... 

Provides a coordinated crop protection industry response to the development of resistance in insect and mite pests. During the last decade, IRAC has formed several international working gi oups to provide practical solutions to mite and insect resistance problems within major crops and pesticide groups. 

Despite the use of 2.5 million tons of pesticide worldwide, approximately 35% of potential crop production is lost to pests. An additional 20% is lost to pests that attack the food post-harvest. Thus, nearly one-half of all potential world food supply is lost to pests despite human efforts to prevent this loss. Pesticides, in addition to saving about 10% of world food supply, cause serious environmental and public health problems. These problems include human pesticide poisonings fish and bird kills destruction of beneficial natural enemies pesticide resistance contamination of food and water with pesticide residues and inadvertent destruction of some crops. 

One reason for the rapid growth in the use of pesticides worldwide has been the "Green Revolution" (5), Although there have been some benefits from pesticide use in agriculture, they also cause significant environmental and public health problems. The same is true in public health where Insecticides have been used to control malaria. However, today Increased resistance to insecticides in mosquitoes and Increased resistance to drugs by the malarial parasite are resulting in an explosive increase of malaria worldwide (5). 

Most biological and cultural pest controls return greater profits than pesticides. For example, biological pest controls are reported to return from 30 to 300 per dollar invested in control (16). Various cultural controls like host plant resistance, crop rotations, and tillage, also return 30 to 300 per dollar Invested in pest control (16). 

Since the mid 1940s, pest populations have been developing resistance to synthetic pesticides. To overcome this resistance, additional pesticide treatments and more costly controls have been required to achieve desired levels of pest control. This costs farmers about 1 billion each year (Pimentel, D., in manuscript). 

Mechanism of action can be an important factor determining selectivity. In the extreme case, one group of organisms has a site of action that is not present in another group. Thus, most of the insecticides that are neurotoxic have very little phytotoxicity indeed, some of them (e.g., the OPs dimethoate, disyston, and demeton-5 -methyl) are good systemic insecticides. Most herbicides that act upon photosynthesis (e.g., triaz-ines and substituted ureas) have very low toxicity to animals (Table 2.7). The resistance of certain strains of insects to insecticides is due to their possessing a mutant form of the site of action, which is insensitive to the pesticide. Examples include certain strains of housefly with knockdown resistance (mutant form of Na+ channel that is insensitive to DDT and pyrethroids) and strains of several species of insects that are resistant to OPs because they have mutant forms of acetylcholinesterase. These... 

Selective toxicity is also important in relation to the development of resistance or tolerance to pollutants from two distinct points of view. On the one hand, there is interest among scientists concerned with crop protection and disease control in mechanisms by which crop pests, vectors of disease, plant pathogens, and weeds develop resistance to pesticides. Understanding the mechanism should point to ways of overcoming resistance, for example, other compounds not affected by resistance mechanisms or synergists to inhibit enzymes that provide a resistance mechanism. On the other hand, the development of resistance can be a useful indication of the environmental impact of pollutants. 

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