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Plant residue definition

If the relevant residue cannot be properly determined using a routine multi-method, an alternative method must be proposed. In the case of residues consisting of a variety of structurally related compounds, a common moiety method may be acceptable in order to avoid the use of an excessive number of methods for individual substances. For example, the relevant residue of isoproturon in plant material is defined as the sum of isoproturon and all metabolites containing the 4-isopropylaniline group. Therefore, residues are determined following hydrolysis as 4-isopropylaniline and are expressed as 4-isopropylaniline equivalents. It is not necessary to validate the method individually for all possible metabolites which are covered by the residue definition (e.g., all metabolites which contain the 4-isopropylaniline group), provided that it is demonstrated that in the first step, the conversion to the common moiety is complete. However, common moiety methods often lack sufficient specificity, and should therefore be avoided if possible. If need be, their use must be justified. [Pg.26]

The toxic effects of selected plant analytes will be assessed by comparison with the toxicides of similar metabolites found in animal metabolism studies. The amount of the analytes reported in the plant metabolism study is one of the important factors used to establish the residue definition. [Pg.49]

Stable to acid and base in the pH range 3-8. Thenylchlor is a chloroacetamide herbicide for the preemergence and post-planting control of annual grass and broad-leaved weeds in paddy rice The residue definition is for the parent, thenylchlor, only... [Pg.585]

Oxime carbamates are generally applied either directly to the tilled soil or sprayed on crops. One of the advantages of oxime carbamates is their short persistence on plants. They are readily degraded into their metabolites shortly after application. However, some of these metabolites have insecticidal properties even more potent than those of the parent compound. For example, the oxidative product of aldicarb is aldicarb sulfoxide, which is observed to be 10-20 times more active as a cholinesterase inhibitor than aldicarb. Other oxime carbamates (e.g., methomyl) have degradates which show no insecticidal activity, have low to negligible ecotoxicity and mammalian toxicity relative to the parent, and are normally nondetectable in crops. Therefore, the residue definition may include the parent oxime carbamate (e.g., methomyl) or parent and metabolites (e.g., aldicarb and its sulfoxide and sulfone metabolites). The tolerance or maximum residue limit (MRL) of pesticides on any food commodity is based on the highest residue concentration detected on mature crops at harvest or the LOQ of the method submitted for enforcement purposes if no detectable residues are found. For example, the tolerances of methomyl in US food commodities range from 0.1 to 6 mg kg for food items and up to 40 mg kg for feed items. ... [Pg.1153]

The residue definition of famoxadone includes only famoxadonefor plants and animals. Forsoil and water, IN-JS940 (CAS No. 157874-97-0) and IN-KZ007 have also been included in the residue definition. [Pg.1178]

The residue definition for plant samples is acetamiprid only. In soil, it includes acetamiprid and three of its... [Pg.1242]

Regulatory position The residue definition of hexythiazox for plant/crops is for hexythiazox itself... [Pg.1316]

An important benefit of the isotopic approach is that below-ground biomass values are not required. The 13C natural abundance isotopic carbon budget approach is based on C3 plants having lower 13C value than C4 plants (Ehleringer 1991 Clay et al. 2006) and that the signatures can be tracked by placing C3 plant residue into a soil derived from C4 plants or vice versa. In these calculations, several definitions are needed. These definitions include... [Pg.204]

The first step is to identify the critical crops and the compounds for which residue studies must be conducted. The breakdown and reaction products and metabolites in treated plants and products are often identified after treatment with a C-14 labeled test substance in plant metabolism studies. The objective is to determine the fate of the parent substance and its metabolites in the crop plants and their processing products. From the results of the studies, the relevant residues are defined residue definition). For example, in plants glyphosate is converted to its main metabolite AMPA (= aminomethylphospohonic acid), which was also studied as part of the residue assessment. [Pg.414]

SOM is composed of a continuum of organic resources from fresh plant residues to stabilized organic matter (OM) or humus (Stevenson, 1994). Although this definition of SOM includes intact plant litter, in this review we will often distinguish between decomposition of litter on the soil surface and decomposition/stabilization of OM within the mineral soil. Within the mineral soil, SOM is often divided into four categories the light fraction, microbial biomass (discussed above), dissolved organic matter (DOM), and stable humic substances. [Pg.4118]

Sediment. The sediment test consists of filtering a definite quantity of milk through a white cotton sediment test disk and observing the character and amount of residue. Efficient use of single-service strainers on dairy farms has reduced the use of sediment tests on milk as deflvered to receiving plants. Although the presence of sediment in milk indicates unsanitary production or handling, its absence does not prove that sanitary conditions always existed. [Pg.364]

The definition of residues for selective anilides in plant samples is summarized... [Pg.329]

In general, neonicotinoids (except for nitenpyram) are metabolized slowly in plants, and remain mainly as the parent compounds. The definition of crop residues is for the acetamiprid and imidacloprid parent molecule. The definition of crop... [Pg.1128]

A sample of hops which had been treated with tetraethyl pyrophosphate showed a negative chemical analysis. The plant material was also extracted and the extract added to the drinking water of test animals and sensitive insects. The animals and insects that drank this treated water for several days showed no reaction. With the sensitive insects it would have been possible to detect even a few parts per million. In addition, there have been extensive commercial field applications of the chemical in dust and spray form to crops such as apples, pears, grapes, celery, broccoli, Brussels sprouts, and others up to within a few days of harvest there has been no detectable poison residue on any of the crops. The lack of poison residue with use of tetraethyl pyrophosphate is due to the fact that it hydrolyzes within a few hours of application, breaking down into transient nonresidual and nonpoisonous chemicals. Thus it is possible to use tetraethyl pyrophosphate well up to harvest time of food products without danger of residual poison on crops. The fact that the chemical is used in extremely small amounts is a definite advantage in respect to freedom from poison residue. [Pg.107]

Zinc fertilizers made from recycled hazardous secondary materials. U.S. EPA promulgated a conditional exclusion from the definition of solid waste for hazardous secondary materials that are recycled to make zinc fertilizers or zinc fertilizer ingredients. Zinc, an important micronutrient for plants and animals, can be removed from zinc-rich manufacturing residue and used to produce zinc micronutrient fertilizer. A second conditional exclusion applies to the zinc fertilizer products made from these secondary materials. [Pg.495]

According to Bassam (1998) who provided a well-established definition, energy crops are those annual and perennial plant species that can be cultivated to produce solid, liquid or gaseous energy feedstock. The organic residues and... [Pg.112]


See other pages where Plant residue definition is mentioned: [Pg.99]    [Pg.329]    [Pg.3]    [Pg.43]    [Pg.177]    [Pg.155]    [Pg.94]    [Pg.146]    [Pg.471]    [Pg.533]    [Pg.473]    [Pg.30]    [Pg.158]    [Pg.409]    [Pg.982]    [Pg.70]    [Pg.156]    [Pg.13]    [Pg.43]    [Pg.14]    [Pg.124]    [Pg.70]    [Pg.580]   
See also in sourсe #XX -- [ Pg.329 ]




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