Rapid field method

Brown et al. [22] have described a rapid field method for detecting down to 2pg of oil in sediments associated with marine oil spills. The method was employed in connection with the Argo Merchant oil spill off Nantuckett in December 1976. 

The Safe Level Concept and the Rapid Field Method... 

This paper establishes toxicologically-safe levels for total residues of parathion, azinphosmethyl, methidathion and their oxons on tree foliage and reports these levels in terms of absorbance units as determined by the rapid field method. Safe levels for a new insecticide, chlorthiophos, are also proposed based on preliminary residue data. Chemical structures of the four insecticides mentioned above are shown in figures 1, 2, 3 and 6. 

Figures IB, 2B and 3B, drawn using the data from Figures 1A, 2A and 3A, give the dissipation curves for the total residues (thion + oxon) of parathion, azinphosmethyl and methidathion. These dissipation curves are similar to the curves obtained when OP residues are determined by the rapid field method as shown by the extensive studies conducted by Gunther et al. (5) which compare gas chromatographic values for thion + oxon with RFM values for total OP residues.

The rapid field method is a kit for making analyses in the field. A leaf punch sampler is used to collect samples of known surface area. The surface residues are removed using 20% NaCl solution and then residues are partitioned into hexane. The hexane is boiled off and the insecticide residues are reacted with 4-(p-nitrobenzyl) pyridine for 3 minutes at 150°C. Addition of base solution produces a purple color whose intensity is measured using a portable mini-spectrophotometer. The absorbance value of the colored solution is used to estimate the residue level present in the collected sample. 

The safe levels established for parathion + paraoxon, azinphosmethyl + azinphosmethyl oxon and methidathion + methi-dation oxon on foliage have absorbance values determined by the rapid field method (4 ) equal to those given in Table III. Absorbance values greater than those listed in Table III signal an unsafe working condition. Field testing can also be conducted by standard gas chromatographic analysis of the leaf disk samples by state-approved laboratories. 

Gunther, F. A. Iwata, Y. Papadopoulou, E. Berck, B. Smith, C. A. Rapid field method for estimating organo-phosphorus insecticide residues on crop foliage. Bui1. Environm. Contam. Toxicol., 1980, 24, 903. 

Esquivel, T. F., and N. Maravalhas. 1973. Rapid field method for evaluating hydrocyanic toxicity of cassava root tubers. 7. Agric. Food Chem. 21(2) 321-22. 

Rossmoore, L.A., Wireman, J.W., and Rossmoore, H.W. (1986). Rapid field method for the detection and enumeration of sulfate reducers. In Biodeterioration 6, Proceedings of the Sixth International Biodeterioration Symposium, pp. 413-419 (S. Barry and D.R. Houghton, eds.), C.A.B. Inti. Mycological Inst., The Biodetn. Soc., United Kingdom. 

RAPID PHOTOMETRIC METHODS FOR WATER ANALYSIS IN FIELD. EXTRACTION-FREE RAPID PROCEDURES FOR THE DETERMINATION OF TRACES OF REGULATED METALS WITH l-(2-PYRIDYLAZO)-NAPHTOL-2... 

Baildown testing is a widely used field method to evaluate the actual thickness of LNAPL product in a monitoring well. Baildown testing involves the rapid removal of fluids from the well, and subsequent monitoring of fluid levels, both the water level or potentiometric surface (oil-water interface) and NAPL level (oil-air interface), with time. Such testing was originally used as a preliminary field method to evaluate recoverability of NAPLs and thus to determine potential locations for recovery wells. All monitoring wells at a site that exhibited a measurable thickness of LNAPL were typically tested. Whether or not all the LNAPL product could be... 

Steps an individual permit holder must take to use an alternate test procedure for regulatory reporting of specific discharges follow. An alternate test procedure differs from those published in the Federal Register for NPDES-certification purposes (Source Federal Register, Title 40, Chapter 1, Subchapter D, Part 136 Vol. 38, No. 199, Oct. 16, 1973 Vol. 41, No. 232, Dec. 1, 1976). Many Hach methods (Hach Company, Loveland, CO, USA) are identical to these published methods and thus are approved by USEPA and highly recommended by the authors for rapid field testing of effluent samples. 

Sampling. Monthly samplings were performed at the deepest point of the water column (depth = 31 m) over a period of 2 years. Because a number of labile reduced species occur in anoxic water samples, special attention has to be given to the sampling and sample pretreatment methods to obtain reliable results. Several approaches have been used to circumvent sampling and storage problems. Rapid field analysis of labile species has been recommended (e.g., ref. 9). This rapid analysis is particularly important in measuring the very labile species of Fe(II) and S(-II). 

Easterling et al. [161] has reported a rapid field screening method for the determination of elemental mercury in soil. This method involves thermal desorption of the mercury onto gold, followed by thermal desorption from the gold film mercury analyser. 

They are rapid field and laboratory assessments. Other methods, such as mineralogy (see next section) and geochemistry, are complex and more costly to carry out. 

The development of fast, reliable and convenient chemical processes is important for the whole field of organic chemistry. In fact, in many cases even a slight drop in chemical yield is acceptable when compensated for by large gains in reaction time or improved ease of handling [12-15]. These features apply in particular to iterative reaction optimization in commercial situations where the reaction time is an important parameter [16]. In particular, the pharmaceutical industry is continuously on the look-out for new rapid synthetic methods and strategies for the discovery and development of new drugs. 

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