River sampling

Several studies have been conducted to measure methyl parathion in streams, rivers, and lakes. A U.S. Geological Survey (USGS) of western streams detected methyl parathion in five river samples taken from four states during a 14-month period in 1970 and 1971. The amount of methyl parathion detected ranged from 0.04 to 0.23 pg/L (Schultz et al. 1973). A later and more extensive USGS study analyzed water samples from major rivers of the United States four times yearly in the period of 1975-1985. Of the 2,861 water samples, 0.1% had detectable levels of methyl parathion (Gilliom et al. 1985). In a study of Arkansas surface waters, samples of lake and river/stream water were collected and analyzed over a three-year period (Senseman et al. 1997). Of the 485 samples collected, methyl parathion was found in one river/stream sample at a maximum concentration of 3.5 pg/L. Results from an EPA study in California detected methyl parathion in 3 of 18 surface drain effluent samples at concentrations of 10-190 ng/kg. Subsurface drain effluent water had concentrations of 10-170 ng/kg in 8 of 60 samples (lARC 1983). 

Surface-water samples are usually collected manually in precleaned polyethylene bottles (from a rubber or plastic boat) from the sea, lakes, and rivers. Sample collection is performed in the front of the bow of boats, against the wind. In the sea, or in larger inland lakes, sufficient distance (about 500 m) in an appropriate wind direction has to be kept between the boat and the research vessel to avoid contamination. The collection of surface water samples from the vessel itself is impossible, considering the heavy metal contamination plume surrounding each ship. Surface water samples are usually taken at 0.3-1 m depth, in order to be representive and to avoid interference by the air/water interfacial layer in which organics and consequently bound heavy metals accumulate. Usually, sample volumes between 0.5 and 21 are collected. Substantially larger volumes could not be handled in a sufficiently contamination-free manner in subsequent sample pretreatment steps. 

Relatively high contents of As in Drava River samples (ME-23 and ME-24) are a consequence of the Drava River catchment area characteristics. 

Fig. 1. Rare earth element plots of uncontaminated rivers. Samples marked with circles are from Bau et al. (2006) and those with triangles from Bau Dulski (1996). Samples marked with squares are from this study.

Fig. 6.2.3. Seasonal variation of alkylphenolic compounds in water (A) and sediment (B) samples from the Anoia river. Sampling points A1 (1.5 km upstream of WWTP, Igualada) A2 (23 km downstream of WWTP) A3 (27 km downstream of WWTP).

CZE was also employed for the analysis of sulphonated azo dyes in river samples. The chemical structures of dyes are shown in Fig. 3.150. Separations were performed in a fused-silica capillary (total length 57 cm effective length, 50 cm 75 pm i.d.). Activation of the capillary was carried out by washing it with 1.0 M NaOH for 15 min, followed by water (5 min) and the running buffer (5 min). The buffer was prepared from 10 mM... 

M. Perez-Urquiza, R. Ferrer and J.L. Beltran, Determination of sulfonated azo dyes in river samples by capillary zone electrophoresis. J. Chromatogr.A, 883 (2000) 277-283. 

Grab samples were collected in one gallon amber glass bottles with Teflon-lined caps at depths of 0.5 to 0.1 m. All center channel samples were collected aboard the AquadeJphia, the boat used by the City of Philadelphia for its own river sampling program. 

Paris DF, Wolfe NL, Steen WC, et al. 1983. Effect of phenol molecular structure on bacterial transformation rate constants in pond and river samples. Appl Environ Microbiol 45 1153-1155. 

The estimates of the sample size obtained in this way are valid for one-dimensional objects, e.g. output of factories, rivers, sampling lines in lakes, stationary sampling points for air monitoring, etc. A sample of papers that are devoted to the application of autocorrelation in sampling schemes is e.g. 

Organic concentrates of water samples from the Rhine River and Meuse River were tested for toxicity by using a 48-h mortality test on fish (Poecilla reticulata) at 3-month intervals for 1 year (11). The river samples were concentrated by adsorption on XAD followed by elution with acetone. Rhine water samples were more toxic than Meuse water samples in most cases (7,12, 13) (see Figure 6). 

In processing volumes of water as large as in the two examples cited, large columns of resin are preferred. In both the Foxhills-Laramie and Suwannee River samples, columns with 8 L of resin and a void volume of 6 L were used. By using eq 1 with a k cutoff of 100, it was calculated that, for the Foxhills-Laramie sample, 460 L of water could... 

This system has been employed quite successfully to process water samples in excess of 1000 L (Table III). In each of the examples cited, a 10-L column of A-7 resin was used with the exception of the Suwannee River sample, this quantity of resin was sufficient to process the entire sample without regenerating the resin. The method of Leen-heer and Noyes (10) differs from the XAD-8 method in that the filtered sample does not require adjustment to pH 2 before concentration. This... 

H NMR data from these seven sites are presented by spectral peak-height ratios in Table III. The sites were listed in order of increasing aromatic plus olefinic carbon percentages. Fulvic acids from all the lake samples are much lower in aromatic plus oleflnic carbon content than those from river samples. These results confirm the hypothesis that autothonous inputs result in dissolved humic substances that have a low aromatic plus oleflnic carbon content. The lake samples also are lower in the ratios of peak 2 (carboxylated chains and aliphatic ketones), peak 3 (carbohydrates), and peak 4 (phenolic tannins and lignins) to peak 1 (branched methyl groups and alicyclic ali-phatics) than are the river samples. 

The Sagavanirktok River is intermediate in aromatic carbon content. This river drains the bogs on the Arctic tundra (allochthonous inputs) and several lakes (autochthonous inputs). Samples from the Suwannee and Calcasieu rivers are very similar in peak-height ratios with the exception of peak 2 1 ratio, which is much lower for the Calcasieu River sample. The data in Table II indicate that the Calcasieu River fulvic acid has a greater ring content... 

The Temi River sample was collected by Robert Stallard of the U.S. Geological Survey. 

The Temi River samples had the largest aromatic carbon content because of inclusion of the humic acid fraction. Tropical blackwater rivers are known to contain large percentages (as much as 30%) of humic acid DOM because of the low-conductivity waters and lack of solubility controls associated with the sandy podzols in the tropical rain forest (24, 25). 

The Tolka river sample was collected in a 500-ml polyethylene container that was previously soaked in 10% sulphuric acid for 1 h and subsequently rinsed with deionised water. 

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