Rhine water

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). 

The XAD procedure was selected on the basis of the comparison of results of complementary methods as mentioned earlier because it is effective in concentrating toxic as well as mutagenic compounds from Rhine water. The investigation demonstrates the application of short-cut biological methods needed for water quality control and complementary to chemical monitoring techniques. 

Figure 7. Variations in the toxicity of Rhine water at Gorinchem -, river discharge --, water temperature --------,...

No mutagenic activity could be detected in the bile of bream from the Meuse River, which contains little activity in the water itself. Seasonal changes in the level of Rhine water mutagenicity roughly coincide with similar changes in the activity of bile from Rhine fish (see Figure 8). 

Piet,G. J. Smeenk,J. G. M. M. (1985). Behavior of organic pollutants in pretreated Rhine water during dune infiltration. In Ground Water Quality, ed. C. H. Ward, W. Giger P.L. McCarty, pp. 122-44. New York John Wiley Sons. 

Admiraal, W., Tubbing, G.M.J. and Breebaart, L. (1995) Effects of phytoplankton on metal partitioning in the lower River Rhine. Water Res., 29, 941-946. 

Parallel tests carried out with ozone and activated carbon quickly demonstrated the undeniable superiority of ozone from all points of view. It was possible to transform this polluted Rhine water into excellent, crystal-clear drinking water by means of relatively small ozone dosages (0.7 to 1.0 gram per cubic meter of water). A series of promising tests has been undertaken with this pilot plant at Ludwigshaven am Rhein, Krefeld, Duisberg, and elsewhere. 

As no cause for this effect could be identified (no physical disturbance, no macro parameters), there is suspicion that the cause may be that River Rhine water of lesser quality is passing by in these periods, possibly as a result of temporary emissions. 

Fig. 8-8. Anion analysis of a Rhine water sample. — Separator column IonPac AS3 eluent 0.0028 mol/L NaHCOj + 0.0022 mol/L Na2C03 flow rate 2.3 mL/min detection suppressed conductivity injection 50 pL Rhine water (Dussel-dorf).

All contaminants identified in Rhine water extracts by GC/MS screening analyses are summarized in Tab. 2. They are arranged either by structural properties or by technical/commercial application. 

Tab. 1 Selected contaminants determined 1 in Rhine water extracts and ion...

Halogenated compounds were detected in higher concentrations in all Rhine water samples investigated. Surprisingly, the halogenated aromatics were highly dominated by brominated compounds comprising brominated phenols, (methoxyphenyl)propionic acids and... 

Noteworthy, a technical application and a subsequent emission of mono-to tribrominated phenols to the aquatic environment has not been reported so far. In contrast, brominated phenols and anisols are well-known organohalogens derived from biogenic formation, but exclusively detected in the marine environment (Ballschmiter 2003). Thus, the origin of brominated phenols in the Rhine water samples is still ambiguous. In any case, the prevalence of brominated substances as compared to chlorinated contaminants in the riverine environment is unusual. 

Tab. 2 Organic contaminants identified in Rhine water samples...

The occurrence of dimethylsulfone in Rhine water samples can be attributed either to industrial sources or to municipial effluents due to its application as technical additive (plasticizer, dispersion agent) and solvent. 

Fig. 2 Ion chromatograms of a third extract derived from a Rhine water sample. Mono- and dibrominated (methxyphenyl)propionic acids appeared as methylated derivatives. The elution pattern is compared with those of authentical reference compounds derived from chemical syntheses. It has to be noted, that the relative concentrations are not reflected by the peak areas or peak heights due to different relative proportions of the ion fragments 172 and 352 m/z within the individual mass spectra (see Fig. 3 and 4).

A second group of still unknown contaminants included mono- and dibrominated hydroxymethylacetophenones. These compounds appeared only unsteadyly and in minor concentration in the Rhine water samples investigated. Hence, they were not considered in quantitative analyses. 

Fig. 6 Mass spectra of a brominated contaminant identified in Rhine water samples (A) and of the reference substance obtained by acylation of 2-bromo-4-methylphenol.

Fig. 8 Ion chromatogramms (m/z 228) of the third extract of a Rhine water sample (A) and of reference substances synthesized (B).

Tab. 3 Quantitative data of selected contaminants in Rhine water samples. All concentrations are given in ng/L.

Additionally, several brominated compounds were identified for the first time as environmental contaminants. Their analytical properties (mass spectral, gas chromatographic and IR spectroscopical data) revealed the occurrence of mono- and dibrominated (methoxyphenyl)propionic acids and hydroxymethylacetophenones. Interestingly, the Rhine water samples investigated were dominated by brominated compounds as compared to chlorinated substances. This is an unusual state of riverine pollution with respect to halogenated compounds. 

In Table lA, the average values and maximum contents of As, Cd, Cr, Pb, Cu, Hg and Zn in unfiltered Rhine water, as measured in Basle and in Lobith at the German/Dutch border are summerised. ... 

The voltammograms of ametryne in model solutions (Fig.3A), and measured in Rhine water, Fig.3B, as well as the relationship of peak hight (ip) vs. analyte concentration is shown in Figs 4A and 4B. 

Fig.4. AdSV peak height vs. concentration of ametryne, measured (A) in bidest. water, (B) in Rhine water.

Fig.9 shows ac tensammetric curves of double distilled, tap, process and Rhine river (Basle) waters as measured in the authors laboratory as compared to distilled water (curve 1, Fig.9). A significant depression of the current is observed for both the process and Rhine water.

In Fig.lOB are shown the curves of Rhine water spiked with 100 to 600 ppb atrazine using direct dpp, as compared to model solutions (Fig.lOA). Passing the water samples (500 ml) through a Sep Pak Cig, however, allows much lower determination limits, of the order of 8 to 20 ppb, even in Rhine water, as shown by the Figs IOC and lOD. 

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