Soil analytical methodology

In the following sections, the nature of chloroacetanilide residues in plants, animal products, water, and soil and the rationale for the analytical methodology that is presented are briefly summarized. Procedures for representative methods are included in detail. The methods presented in this article are among the best available at this time, but analytical technology continues to improve. Future directions for acetanilide residue methodology for environmental monitoring are discussed at the end of the article. 

An example of adequate sample homogenization is given in Table 4. The experiment was conducted with two replicate treated soil samples. Each replicate was analyzed in duplicate. Three different sample aliquots (2, 5 and 10 g) were used from each replicate. Analyses of controls and fortified samples were also conducted concurrently with treated samples to evaluate method performance (i.e., extraction recoveries). These results show that residue values are the same regardless of sample size. Thus, thorough homogenization of soil samples coupled with mgged analytical methodology provides for satisfactory residue analysis. 

Studies were initiated at Iowa State University in 1977 to determine if pesticides would be contained and degraded when deposited in water/soil systems. Although the addition of known amounts of the selected pesticides was controlled, the physical environment was not temperature, humidity, wind speed, etc. were normal for the climate of Central Iowa. Four herbicides and two insecticides were chosen on the basis of three factors. Firstly, they represented six different families of pesticides. The four herbicides, alachlor, atrazine, trifluralin, and 2,4-D ester, represent the acetanilides, triazines, dinitroanilines, and phenoxy acid herbicides, respectively. The two insecticides, carbaryl and para-thion, represent the carbamate and organophosphorus insecticides, respectively. Secondly, the pesticides were chosen on the basis of current and projected use in Iowa Q) and the Midwest. Thirdly, the chosen pesticides were ones for which analytical methodology was available. 

Huffman, E. W. D., and Stuber, H. A. (1985). Analytical methodology for elemental analysis of humic substances. In Humic Substances in Soil, Sediment, and Water. Geochemistry, Isolation, and Characterization, Aiken, G. R., McKnight, D. M., Wershaw, R. L., and Mac-Carthy, P., eds., John Wiley Sons, New York, pp. 433 455. 

Solch JG, Ferguson GL, TiernanTO, VanNess BF, Garrett JH, Wagel DJ, Taylor ML (1986), in Chlorinated Dioxins and Dibenzofurans in the Total Environment IV . Analytical methodology for determination of 2,3,7,8-TCDD in soils" p. 377-397, Eds. Rappe C, Choudhary G, Keith LH Butterworth Publishers, Boston... 

Lioy P New Jersey University of Environmental and Occupational Health Sciences Institute, Piscataway NJ Refinement of exposure/dose models. Comparison of bioavailability of elemental waste laden soils using in vivo and in vitro analytical methodology DOE... 

The determination of Po is relatively straightforward, due to the ease of source preparation by spontaneous deposition onto metal surfaces and the uncomplicated alpha spectrum. Although several optimisation studies have been carried out, published source preparation methods remain remarkably diverse. For this review about 130 papers mainly focussed on analytical methodology of Po were collected and critically examined. The literature surveyed included analysis of air, fresh water, rainwater, seawater, soil, sediment, coal, tobacco, phosphogypsum, foodstuffs, marine organisms, vegetation, human bone, and biota (Table 3). 

Many methods are available for analysis of petroleum hydrocarbon products, particularly in water and soil matrices. The current literature includes a number of studies that document the performance and limitations of the commonly used methods. Method modifications and new methods are being investigated to provide better information about the petroleum component content of environmental samples. However, the available analytical methodology alone may not provide adequate information for those who evaluate the movement of petroleum components in the environment or evaluate the health risks posed to humans (Heath et al. 1993a). 

The environmental relevance of OCPs yielded a number of research works aimed at their determination in the different environmental matrices down to trace levels, using gas chromatography (GC) as the chosen separation technique. In the following, the latest analytical methodologies to be used for the determination of OCPs in two such important environmental matrices as water and soil will be described. 

Work in the 1980s established concentration levels to be expected in atmospheres remote from the source when TALs were routinely used in gasoline. Typically, these would be at the ngm level. Ionic lead would also be at similar levels. Ionic leads in waters are also very low (at about the ng L level), with TALs being very low. There is little information about organolead species in sediments and soil. The analytical methodologies are discussed in Section 12.13.5. A recent tabular summary of organolead species detected in the various environmental compartments at the levels noted above is given in Ref 149. 

Tables of acid/base Interactions and thermodynamic references are available for predictions of homogeneous behaviour, e.g. (62,63]. Another complication is the result of soil chemistry. This can be especially important at trace levels when speclatlon is difficult because analytical methodologies may not have the required molecular sensitivities.

From Sturgeon RE (2000) Current practice and recent developments in analytical methodology for trace element analysis of soils, plants, and water. Communications in Soil Science and Plant Analysis 3A A A-A 4)-. 1479-1512. 

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