Sampling of soil

Inter-laboratory control for collecting samples of soils from cell N36E46 was performed, with AEA, XRE, ICP-MS employed, at the Institute of Geochemistry, Irkutsk, Russia and Kingston University, England. 

At that time few micro-organisms capable of using methanol as sole source of carbon methylotrophs and energy (methylotrophs) had been isolated, and so steps were taken to isolate such organisms from samples of soil, water and vegetation. 

Methyl parathion may also be released to soils by improper handling of pesticide formulations during processing or handling. In a sampling of soils collected from processing facilities in Illinois, methyl parathion was detected in soil at 2 of the 49 sites tested (Krapac et al. 1995). 

In random samples of soil taken from five Alabama counties, only 3 of 46 soil samples contained methyl parathion. The concentration in these samples was <0.1 ppm (Albright et al. 1974). Aspartofthe National Soils Monitoring Program, soil and crop samples from 37 states were analyzed for methyl parathion during 1972. Methyl parathion was detected in only 1 soil sample, at a concentration of <0.1 ppm and taken from South Dakota, out of 1,246 total samples taken from the 37 states (Carey et al. 1979). In soil and sediment samples collected from a watershed area in Mississippi, methyl parathion was not detected in the soil samples. In three wetland sediment cores, however, measurable concentrations of methyl parathion were detected during application season (Cooper 1991). 

Soil properties A Soil texture (sand, silt, clay), organic matter/carbon content, and pH Stones, roots, and hardpans must be largely absent to allow representative sampling of soil profile Soil properties should appear uniform over test site Soil texture data should be available at time of site selection. Soil properties must match study purpose. This can be realistic use conditions, realistic worst-case or worst-case in terms of agrochemical mobility and persistence Must ensure that the majority of samples can be taken from the deepest sampling horizon. Information about sub-soils can be obtained from soil maps, test coring and on-site interviews... 

Relative Bioavailability of Lead in Various Samples of Soil from Hazardous Waste Sites as Assessed in Immature Swine... 

Computers are well suited to the manipulation of numbers, but the ES relies on symbolic computation, in which symbols stand for properties, concepts, and relationships. The degree to which an ES can manage a task may depend on the complexity of the problem. For example, computer vision is an area of great interest within AI and many programs exist that can, without human assistance, use the output from a digital camera to extract information, such as the characters on a car number plate. However, automatic analysis of more complex images, such as a sample of soil viewed through a microscope, is far... 

Shacklette H.T., Boemgen J.G. Element concentrations in soils and other surficial materials of the conterminous United States an account of the concentrations of 50 chemical elements in samples of soils and other regoliths. Washington, 1984. 

The NO + 03 chemiluminescent reaction [Reactions (1-3)] is utilized in two commercially available GC detectors, the TEA detector, manufactured by Thermal Electric Corporation (Saddle Brook, NJ), and two nitrogen-selective detectors, manufactured by Thermal Electric Corporation and Antek Instruments, respectively. The TEA detector provides a highly sensitive and selective means of analyzing samples for A-nitrosamines, many of which are known carcinogens. These compounds can be found in such diverse matrices as foods, cosmetics, tobacco products, and environmental samples of soil and water. The TEA detector can also be used to quantify nitroaromatics. This class of compounds includes many explosives and various reactive intermediates used in the chemical industry [121]. Several nitroaromatics are known carcinogens, and are found as environmental contaminants. They have been repeatedly identified in organic aerosol particles, formed from the reaction of polycyclic aromatic hydrocarbons with atmospheric nitric acid at the particle surface [122-124], The TEA detector is extremely selective, which aids analyses in complex matrices, but also severely limits the number of potential applications for the detector [125-127],... 

In this system, choline formed by acetylcholinesterase is oxidized by choline oxidase and the hydrogen peroxide produced is determined using the luminol/peroxidase CL reaction. The sensor has been used for the analysis of Paraoxon and Aldicarb pesticides, with detection limits of 0.75 pg/L and 4 pg/ L, respectively. Recoveries in the range of 81-108% in contaminated samples of soils and vegetables were obtained. 

Christman et al. [72] gave details of procedures for extraction, clean-up, and concentration of samples of soil prior to the determination of their content of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans by gas chromatography and by gas chromatography-mass spectrometry. Instrumental parameters are also included. Some typical results are tabulated. 

Mills and Alexander [4] have discussed the factors affecting the formation of dimethylnitrosamine in samples of soil. Dimethylnitrosamine was formed as readily in sterilized samples as in non-sterile samples, indicating that, although micro organisms can carry out an enzymatic nitrosation in some soils, dimethylnitrosamine can be formed by a non-enzymatic reaction, even at near neutral conditions. The presence of organic matter appears to be important in promoting nitrosation in the presence of the requisite precursors. 

Cotterill [119] used the soil extraction method devised by McKone [120] in which a 25g sample of soil was extracted with 50ml of methanol by shaking on a wrist-action shaker for lh. The resulting soil slurry was filtered through a Whatman No. 42 filter-paper. For gas chromatography, a 2ml... 

The recoveries obtained for urons from samples of soil are shown in Table 9.16. Samples of soil were fortified by adding known volumes of solutions containing (a) Monuron, Metobromuron, Diuron and Chlorbromuron or (b) Monolinuron, Chlorotoluron, Tinuron and Chloroxuron. 

The Analysis of Agricultural Materials, 2nd edn, R.B. 427. HMSO, London, (1979) Method 2, p. 6. Preparation of Samples of soil Method 8, p. 21. Boron, water soluble in soil Method 57, p. 134. Nitrogen in soil Method 62, p. 148. Organic matter in soil Method 63, p. 151. Particle size distribution in soil... 

Look up in a reference book and explain exactly what is involved in taking and preserving a sample of soil to be analyzed for nitrate. 

This project was designed to demonstrate that the static water model ecosystems can be scaled up in size to provide sufficient amounts of biomass, soil, and water to study metabolism kinetics of pesticides. Fourteen kg of soil, treated with [l C]-trifluralin at 10 ppm, was flooded with 84 liters water. Blue-gill fish, snails, daphnids, and algae were exposed to this system for 72 days. Samples of soil, water, and organisms were periodically analyzed for trifluralin and eight metabolites. 

Finally you have your laboratory costs. For even a modest site involving petroleum where you are miming 30-50 samples per month, the cost can exceed 300,000 per month. A good and fully equipped laboratory can exceed 500,000 in costs, and a single sample of soil by GC/MS can exceed 2500 when you include labor to collect the sample, transportation, chain of custody, and costs for analyses. If you have a radioactive program, the costs can double or triple. 

Worked Example 3.10. Here, we will consider a real situation. There is thought to be contamination from a zinc smelting plant, so a sample of soil from near the smelter is collected and digested in sulfuric acid (of concentration 0.01 mol dm in order to leach out the soluble zinc as the sulfate salt. 

Worked Example 7.1. A sample of soil, thought to be contaminated with a herbicide, was collected and all traces of the residual herbicide were removed by digesting in hot water. A sample of known concentration (10 mol dm = 10 mol cm ) gave a limiting current, /nn, of 3.12 mA. What is the concentration of the herbicide in the soil sample if the limiting current is found to be 0.442 mA ... 

Another sample of soil was analysed at the same RDE, under the same stirring conditions, but in this case a current of 1.76 mA was recorded. What was the concentration of herbicide in the analyte sample ... 

Mean values (with standard deviations) of four trifluralin analyses on five field samples of soil receiving emulsifiable concentrate, sampled from 13 to 139 days after application. 

C. botulinum is widely distributed in the environment. The number of Clostridium- po itive samples of soil and bottom sediments ranges from 3 to 100%. C. botulinum type A dominates in soil from the western states of the U.S., whereas type B is predominant in soil samples from the eastern states. C. botulinum type B is most frequently found in European soil, although type A predominates in Italy. In Japanese soil, types C, D or E are prevalent. C. botulinum type F dominates in Paraguayan soil (Dodds, 1993 a,b). 

Mills, A.L. and Alexander, M. Factors affecting dimethylnitrosamine formation in samples of soil and water, J. Environ. Qual., 5(4) 437-440, 1976. 

Horticulture Pit. Core samples of soil of about 100 g size to a depth of 10 cm and liquid samples of 500 mL were taken from eight sampling points spaced uniformly across the pit surface. Each sample was then solvent extracted individually and the pesticides and degradation products were separated and quantitated. 

Figure 3. Plots of the pesticide concentrations in samples of soil (o) and water (X) taken from the Horticulture pit during 1977-1979.

A) A 100-200-g sample of soil was thawed, placed in an extraction thimble, and extracted with redistilled isopropyl alcohol in a Soxhlet extractor for 48 h. Some of these alcohol extracts were analyzed for... 

B) A 200-g sample of soil was loosely packed in a 24 x 40 cm chromatography colunm and sequentially extracted with redistilled organic solvents at room temperature and a flow rate of 0.5 mL per minute in the following order 200 mL hexane 100 mL hexane + 100 mL methylene chloride 200 mL methylene chloride 100 mL methylene chloride + 100 mL ethyl acetate 200 mL ethyl acetate 100 mL ethyl acetate +100 mL methyl alcohol 200 mL methyl alcohol 100 mL methyl alcohol + 100 mL triply distilled water 800 mL triply distilled water. Each extract was taken to dryness over nitrogen gas except the aqueous one, which was evaporated with a rotary evaporator at 45 °C. Each residue was weighed and bioassayed. 

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