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Rapid and highly sensitive trace analysis of cyanide water pollutant in an alligator teeth-shaped PDMS microfluidic channel was investigated using surface-enhanced Raman spectroscopy. Compared with previously reported analytical methods, the detection sensitivity was enhanced by several orders of magnitude.
From 1991 onward, the European Union (EU) member states have had to comply with the Nitrates Directive. The aim of this directive is to sustainably protect ground and surface waters from pollution with nitrogen (nitrate) originating from agriculture. Agriculture is, on an EU level, the largest single source of nitrate (runoff, leaching) pollution, although households and industries also contribute to some extent. An important element in the directive is the reporting every 4 years on the monitoring of ground- and surface-water quality. Furthermore, all 15 member states are compelled to designate so-called Nitrate Vulnerable Zones (NVZs). These are regions where the nitrate concentrations in the groundwater amount to 50 mg/l or more. In addition to Codes of Good Agricultural Practice, valid on a countrywide basis and often consisting of voluntary-based measures, specific Action Programmes with mandatory measures have to be developed for the NVZs. The first reporting period ended in 1995. This paper describes the progress in member states" compliance with the Nitrates Directive during the second period (1996-1999), with a focus on the agricultural practices and action programmes. An evaluation of the member states' reports shows that good progress is being made on the farmers" awareness of the need to comply with EU regulations on the protection of the aquatic environment. Action programmes are valuable tools to enforce measures that lead to a reduction of the water pollution by agricultural activities. Regional projects show that significant improvements can be achieved (e.g., reduced fertiliser inputs) while maintaining crop yields and thus maintaining the economic potential of agriculture.
Ten pesticides: aldicarb, aldicard sulfone, aldicarb oxide, carbofuran, propoxur, methomyl, diuron, linuron, alachlor and parathion-methyl, found as water pollutants in Cyprus, were evaluated for their genotoxicity potential with the Mutatox test, both directly and after exogenous activation with S9 hepatic enzymes. A dark variant (M 169) of the Photobacterium phosphoreum was used as the test organism. Trials were undertaken in triplicate using ground-water spiked with pesticides solutions at testing concentration theoretically corresponding to acute effects of 0.004%, up to a maximum of 2%. All tested pesticides were found to be 'suspect genotoxic' directly and after S-9 activation, except for Alachlor which after S-9 activation was found to be 'genotoxic' at 30 micrograms/l. Among the ten pesticides Linuron was found to be 'suspect genotoxic' after S-9 activation at the lowest concentration, i.e. 2 micrograms/l. Genotoxicity after activation with S-9 was demonstrated at a concentration 1-3 orders of magnitude lower than the respective concentration for direct genotoxic effects. Moreover, genotoxicity after S-9 was developed at levels where the acute toxic effects (Microtox) were 'non measurable' to 'negligible'. The investigation of possible genotoxic effects provides essential information on the impacts of pesticides on the Ecosystem and can contribute to the selection of pesticides with the least possible effects.
Acute, subacute, in vitro, and animal experiments were performed in the spring and fall of 1981. In the course of these investigations, samples from bank-filtered drinking-water wells of Vác, a town along the Danube; from three neighboring observation wells; from water transported from the opposite side of the Danube; from a drinking-water well of a town farther northward; and from Danube water were examined. The aim of the study was to detect whether any of the water samples became contaminated by toxic chemicals. The most severe changes were found in two observation wells (G4 and G2). The drinking-water samples of the wells in Vác (Nos. 1-5) proved to be contaminated, and toxic effects of different degrees were also induced by other wells of Vác. The Danube water caused changes in some tests only; the control drinking-water well, the samples of the K3 observation well, and of the well on the opposite side of the Danube examined in the fall only did not cause any alterations. The toxicity was confirmed by the elevated hemolysis by the genotoxic effects on human erythrocytes and leukocytes, by the functional changes observed in the nervous system of rats, by alterations detected in the electric activity of the rats' brains, in the learning ability and the behavior of the rats, by the increase in the cytochrome P-450 enzyme level of the liver, and by the chromosome aberrations emerging in mice. The changes were caused by different compounds of low and high boiling points escaping with water vapor or with organic solvents. On the basis of the investigations, the water proved to be inappropriate for human consumption.
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The scientific research literature is reviewed (i) for evidence of how much reduction in nonpoint source pollution can be achieved by installing buffers on crop land, (ii) to summarize important factors that can affect this response, and (iii) to identify remaining major information gaps that limit our ability to make probable estimates. This review is intended to clarify the current scientific foundation of the USDA and similar buffer programs designed in part for water pollution abatement and to highlight important research needs. At this time, research reports are lacking that quantify a change in pollutant amounts (concentration and/or load) in streams or lakes in response to converting portions of cropped land to buffers. Most evidence that such a change should occur is indirect, coming from site-scale studies of individual functions of buffers that act to retain pollutants from runoff: (1) reduce surface runoff from fields, (2) filter surface runoff from fields, (3) filter groundwater runoff from fields, (4) reduce bank erosion, and (5) filter stream water. The term filter is used here to encompass the range of specific processes that act to reduce pollutant amounts in runoff flow. A consensus of experimental research on functions of buffers clearly shows that they can substantially limit sediment runoff from fields, retain sediment and sediment-bound pollutants from surface runoff, and remove nitrate N from groundwater runoff. Less certain is the magnitude of these functions compared to the cultivated crop condition that buffers would replace within the context of buffer installation programs. Other evidence suggests that buffer installation can substantially reduce bank erosion sources of sediment under certain circumstances. Studies have yet to address the degree to which buffer installation can enhance channel processes that remove pollutants from stream flow. Mathematical models offer an alternative way to develop estimates for water quality changes in response to buffer installation. Numerous site conditions and buffer design factors have been identified that can determine the magnitude of each buffer function. Accurate models must be able to account for and integrate these functions and factors over whole watersheds. At this time, only pollutant runoff and surface filtration functions have been modeled to this extent. Capability is increasing as research data is produced, models become more comprehensive, and new techniques provide means to describe variable conditions across watersheds. A great deal of professional judgment is still required to extrapolate current knowledge of buffer functions into broadly accurate estimates of water pollution abatement in response to buffer installation on crop land. Much important research remains to be done to improve this capability. The greatest need is to produce direct quantitative evidence of this response. Such data would confirm the hypothesis and enable direct testing of watershed-scale prediction models as they become available. Further study of individual pollution control functions is also needed, particularly to generate comparative evidence for how much they can be manipulated through buffer installation and management.
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The effects of an increasing downriver pollution gradient on the reproductive system of Astyanax fasciatus were investigated in the Rio dos Sinos, RS. The comparison of mean oocyte diameters, gonadal indices and gonado-somatic relationships of specimens captured in polluted areas with individuals from unpolluted reference sites revealed a significant decrease of these parameters with increasing water pollution. High loads of organic and industrial sewage are considered responsible for these effects. Condition factors showed an inverse relationship, and increased significantly in down-river polluted areas. The declining gonadal indices showed that energy was allocated to somatic growth. The results of the study recommend the use of A. fasciatus in biomonitoring essays.
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All five members of a family developed subacutely mental confusion and/or truncal ataxia. Symptoms and signs of polyneuropathy were seen later. The well water in the patients' home contained 400 ppm acrylamide. The present cases are unique in that they are cases of acrylamide poisoning induced by oral intake and percutaneous penetration, and that central nervous system symptoms were prominent.
The effects of heavy metal pollutants on aquatic birds have been widely studied in ecotoxicological investigations; however, the predominant focus has been on the postnatal period of life. Limited information on the adverse effects of metals to bird eggs is available. The possible toxic effects of lead and copper were studied in mallard eggs. After the accidental severe heavy metal pollution of the Tisa river (Hungary) in March 2000, these metals were detected in the highest concentration in both the water and the sediment, reaching far beyond acceptable concentrations. Pb treatment (2.9 mg/L) significantly increased the rate of mortality after a single immersion of the eggs into polluted water for 30 min. The rate of dead embryos significantly increased after the combined exposure to Cu and Pb (0.86 and 2.9 mg/L, respectively) both in the single- (once for 30 min) and in the multiple- (10s daily during first trimester of incubation) immersion groups. It was concluded that elevated metal concentrations similar to those found in the Tisa river after the tailing dam failure may cause toxic effects (mortality and teratogenicity) upon exposure of mallard eggs.
The study presents the results of physical-chemical examinations of the coastal water of the Baltic Sea, carried out from 1984-1988 on 18 sampling stations located in the region of Gdynia and Gdańsk, and along the Hel Peninsula. The samples were collected weekly from the surface of water in the distance of about 5 m from the shore during 5 years. The results indicated a considerable physical and chemical pollution of the coastal water of Gdańsk Bay. Noted is the absence of the criteria of sanitary evaluation of the sea water regarding its usability for recreation. Mean concentration values of phosphates, ammonia compounds and nitrites as well as BOD5 in the coastal water of Gdańsk Bay were on the average 5-10 times higher than in the water of the open Baltic Sea. If the level of reference is the open sea water, it must be assumed that the coastal water of the Gdańsk Bay is strongly polluted. Useful seems to be the determination of the level of the physical and chemical pollution of the sea coastal water by comparison of certain indices with the values characteristic for open, clean sea or by relating them to the values making the "background" for the sea area examined. There is a need to elaborate evaluation criteria of physical and chemical pollution of sea coastal waters.