Pesticides alternatives

Tables 14.6, 14.7, 14.8, 14.9 and 14.10 provide further insight into the comparative properties and toxicity of pesticides applied on organic and conventional farms to treat a given type of pest. Table 14.6 lists the primary pesticides approved for use on organic farms and their uses and target pests. Tables 14.7-14.10 again list the major organic pesticides, along with two or three conventional pesticide alternatives that are used by conventional farmers to manage the same pest problems. Tables 14.7 and 14.8 summarize the rates of application of these pesticides, while Tables 14.9 and 14.10 focus on relative measures of toxicity to mammals and other organisms.

Cuperus, G. 1995. Pesticide alternatives. In Stored Product Management (V. Krischik, G. Cuperas, and D. Galliart, eds). Oklahoma Cooperative Extension Service Publication, E-912. 

The selectivity of the election capture detector, coupled with its extreme sensitivity (down to 1 pg), makes it very useful for compounds such as tiie benzodiazepines or halogenated pesticides. Alternatively, the great sensitivity of the detector may be utilised by preparing derivatives with reagents such as heptafluorobutjric anhyctiide. For some compounds the sensitivity of tiiis detector may exceed that of the mass spectrometer. 

Begin this method with the Soxhlet extraction of approximately 1 to 10 g of soil or sediment with 90% methanol/10% distilled water. The methanol will effectively wet the soil and sediments and remove the majority of the organochlorine pesticides. Alternatively, the soils and sediments may be extracted with heated solvent under pressure using the accelerated solvent extractor by Dionex (see Chapter 9 on the extraction of food and natural materials for details of analysis). After the extraction is complete, dilute the methanol extract with distilled water to a final concentration of 10% methanol. Process the extract through a C-18 cartridge as described in Section 7.10.1. In this case, the C-18 sorbent with greater hydrophobicity is used because of the 10% methanol present in the sample. Elute the cartridge with ethyl acetate and analyze by GC/MS. 

T. Cairns and J. Sherma, eds.. Emerging Strategiesfor Pesticide Analysis, CRC Press, Boca Raton, Fla., 1992, 368 pp. From the series Modem Methods of Pesticide Analysis, presents survey of improvements in extraction and cleanup, detailed descriptions of alternative analytical methods, latest appHcations, and up-to-date references. 

Sample Cleanup. The recoveries from a quick cleanup method for waste solvents based on sample filtration through a Elorisd and sodium sulfate column are given in Table 2 (40). This method offers an alternative for analysts who need to confirm the presence or absence of pesticides or PCBs. 

Reaction with Amines and Ammonia. Carbonates react with amines and ammonia to produce carbamates or ureas. This reaction can be used as an alternative route to producing carbamate pesticides. 

Biosensors ai e widely used to the detection of hazardous contaminants in foodstuffs, soil and fresh waters. Due to high sensitivity, simple design, low cost and real-time measurement mode biosensors ai e considered as an alternative to conventional analytical techniques, e.g. GC or HPLC. Although the sensitivity and selectivity of contaminant detection is mainly determined by a biological component, i.e. enzyme or antibodies, the biosensor performance can be efficiently controlled by the optimization of its assembly and working conditions. In this report, the prospects to the improvement of pesticide detection with cholinesterase sensors based on modified screen-printed electrodes are summarized. The following opportunities for the controlled improvement of analytical characteristics of anticholinesterase pesticides ai e discussed ... 

The reaction of enamines with iminium salts provides an alternative route to Mannich bases which are an attractive class of compounds, since they have found many applications (synthesis of drugs, pesticides, synthetic building blocks, etc.). This methodology has several basic advantages compared to the classic aminomethylation procedure15-18-24 ... 

This analysis has demonstrated that pesticide use in the world could be reduced by approximately 50% without any reduction in crop yields (in some cases increased yields) or the food supply. This effort would require applying pesticides only-when-necessary plus using various combinations of the nonchemical control alternatives currently available (34). Although food production costs might Increase slightly (0.5% to 1%), the added costs would be more than offset by the positive benefits to public health and the environment (15). 

Chau ASY. 1972. Confirmation of pesticide residue identity V. Alternative procedure for derivative formation in solid matrix for the confirmation of alpha- and beta endosulfan by gas chromatography. J Assoc Off Anal Chem 55 1228-1231. 

The environmental fate and behavior of compounds depends on their physical, chemical, and biochemical properties. Individual OPs differ considerably from one another in their properties and, consequently, in their environmental behavior and the way they are used as pesticides. Pesticide chemists and formulators have been able to exploit the properties of individual OPs in order to achieve more effective and more environment-friendly pest control, for example, in the development of compounds like chlorfenviphos, which has enough stability and a sufficiently low vapor pressure to be effective as an insecticidal seed dressing, but, like other OPs, is readily biodegradable thus, it was introduced as a more environment-friendly alternative to persistent OCs as a seed dressing. 

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