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In an attempt to reduce the risk of infection in natural bathing waters the European Union is in the process of improving the Bathing Water Directive 76/160/EWG, which regulates the safety of such waters. The proposal contains several positive innovations which will improve the protection of the bathers: (1) health-related indicators, (2) harmonized detection methods, (3) requirements for active bathing water management, and (4) stricter standards for coastal waters. One of the most salient features of the current draft is the introduction of bacterial standards that are more stringent for coastal than for fresh waters. This decision on different standards seems unjustified: it was taken solely on the grounds that in two epidemiological studies-one carried out in coastal, the other in fresh waters-the maximum excess rate of gastroenteritis among bathers in coastal waters was higher than among bathers in fresh waters. However, it was not taken into account that the concentrations of bacterial indicators at which the gastroenteritis rate began to increase was nearly identical in both studies. The ratio between the standard concentrations of E. coli and intestinal enterococci in the draft was set at 2.5. This value does not correspond to the ratio found in German surface waters with low pollution levels, with ratios ranging from 2.7 to 4.0, and to the even higher ratios found in raw and treated sewage effluents. As a consequence in a majority of cases the non-compliance of bathing waters in Germany would be caused exclusively by a violation of E. coli standards. In assessing risks of infection it must also be taken into account that the adequacy of E. coli and intestinal enterococci for signaling the presence of viruses in water is far from optimal. The decay of viruses in water-estimated by the decay of bacteriophages-was found to be substantially slower than the die-off of indicator bacteria.

Welcome Bay and Chaguaramas Bay in the northwest peninsula of Trinidad contain large marinas and smaller sections of bathing beaches. Bacteriological surveys were conducted at both bays to assess water quality and to determine potential sources of pollution. These surveys were conducted during the wet season of 1996 and the dry season of 1997. Eleven sample stations were established at Welcome Bay and 12 at Chaguaramas Bay. Freshwater samples were collected from rivers and drains within the survey area. Marine water samples were collected from marinas, bathing beaches and inshore and outer areas at both bays. Five water samples were collected from each sampling station during the wet season of 1996 and six during the dry season of 1997. The membrane filter technique was used to determine faecal coliform and Escherichia coli levels in all samples. There was a seasonal effect on water quality, with significantly higher faecal coliform levels in the wet season, when water quality was not in compliance with international standards. This represents a potential health risk in bathing areas. Water quality was better at the outer area of both bays. Water quality at the inner bay areas was most likely adversely affected by land-based sources of pollution identified in this study. These sources include three drains and two rivers, which discharged into the bays. Yachts were apparently not a source of sewage pollution: there was no significant relationship between yacht number and faecal coliform levels.

This paper presents a framework for analyzing the economic, health, and recreation implications of swim closures related to high fecal indicator bacteria (FIB) levels. The framework utilizes benefit transfer policy analysis to provide a practical procedure for estimating the effectiveness of recreational water quality policies. Evaluation criteria include the rates of intended and unintended management outcomes, whether the chosen protocols generate closures with positive net economic benefits to swimmers, and the number of predicted illnesses the policy is able to prevent. We demonstrate the framework through a case study of a Lake Michigan freshwater beach using existing water quality and visitor data from 1998 to 2001. We find that a typical closure causes a net economic loss among would-be swimmers totaling dollars 1274-37,030/day, depending on the value assumptions used. Unnecessary closures, caused by high indicator variability and a 24-h time delay between when samples are taken and the management decision can be made, occurred on 14 (12%) out of 118 monitored summer days. Days with high FIB levels when the swim area is open are also common but do relatively little economic harm in comparison. Also, even if the closure policy could be implemented daily and perfectly without error, only about 42% of predicted illnesses would be avoided. These conclusions were sensitive to the relative values and risk preferences that swimmers have for recreation access and avoiding health effects, suggesting a need for further study of the impacts of recreational water quality policies on individuals.

The current European standards for microbiological quality of bathing water (i.e., all running or still fresh waters or parts thereof and/or sea water [with the exception of water intended for therapeutic purposes and water used in swimming pools]) were issued in 1976 and are currently undergoing revision. In this article, the authors propose parameters for select microorganism indicators to assist in the establishment of public-health-based objectives for fresh and marine water quality. A type-II meta-analysis of the results of 18 published epidemiological studies was implemented in an attempt to characterize the relationship(s) between concentrations of bacterial indicators and rates of acute gastrointestinal diseases among bathers who had used fresh or marine water for recreational purposes. The authors fit multiple linear-regression models, which allowed for random effects across studies, to derive dose-response curves. Several confounders and effect modifiers were controlled for in the analyses. Risks were then estimated for a hypothetical individual who would bathe 20 times/yr in water that contained a given concentration of microorganisms. For fresh-water-associated highly credible gastrointestinal illnesses, a level of 10 fecal coliforms/100 ml water yielded an attributable risk of 0.2 cases/1,000 person-years; a risk of 2 cases/1,000 person-years was found for fecal streptococci. The corresponding yearly attributable risks were 1 and 13 cases/1,000 person-years, respectively, for 100 bacteria/100 ml fresh water. Risks associated with fecal coliforms were found to be lower in marine water than in fresh water. Irrespective of the type of water examined, total coliforms were related only weakly with acute digestive morbidity. Developers of future bathing-water standards should state the level of risk deemed acceptable for public health. The authors of this study maintain that levels of fecal coliforms and fecal streptococci should be used as criteria for infectious risk management associated with bodies of marine and fresh water used for recreational purposes.

Swimming advisories due to excessive Escherichia coli concentrations are common at 63rd Street Beach, Chicago, Ill. An intensive study was undertaken to characterize the source and fate of E. coli in beach water and sand at the beach. From April through September 2000, water and sand samples were collected daily or twice daily at two depths on three consecutive days per week (water samples, n = 1,747; sand samples, n = 858); hydrometeorological conditions and bird and bather distributions were also recorded. E. coli concentrations in sand and water were significantly correlated, with the highest concentration being found in foreshore sand, followed by those in submerged sediment and water of increasing depth. Gull contributions to E. coli densities in sand and water were most apparent on the day following gull activity in a given area. E. coli recolonized newly placed foreshore sand within 2 weeks. Analysis of variance, correlation, cluster analyses, concentration gradients, temporal-spatial distribution, demographic patterns, and DNA fingerprinting suggest that E. coli may be able to sustain population density in temperate beach sand during summer months without external inputs. This research presents evidence that foreshore beach sand (i) plays a major role in bacterial lake water quality, (ii) is an important non-point source of E. coli to lake water rather than a net sink, (iii) may be environmentally, and perhaps hygienically, problematic, and (iv) is possibly capable of supporting an autochthonous, high density of indicator bacteria for sustained periods, independent of lake, human, or animal input.

This paper presents a preliminary attempt at obtaining an order-of-magnitude estimate of the global burden of disease (GBD) of human infectious diseases associated with swimming/bathing in coastal waters polluted by wastewater, and eating raw or lightly steamed filter-feeding shellfish harvested from such waters. Such diseases will be termed thalassogenic--caused by the sea. Until recently these human health effects have been viewed primarily as local phenomena, not generally included in the world agenda of marine scientists dealing with global marine pollution problems. The massive global scale of the problem can be visualized when one considers that the wastewater and human body wastes of a significant portion of the world's population who reside along the coastline or in the vicinity of the sea are discharged daily, directly or indirectly, into the marine coastal waters, much of it with little or no treatment. Every cubic metre of raw domestic wastewater discharged into the sea can carry millions of infectious doses of pathogenic microorganisms. It is estimated that globally, foreign and local tourists together spend some 2 billion man-days annually at coastal recreational resorts and many are often exposed there to coastal waters polluted by wastewater. Annually some 800 million meals of potentially contaminated filter-feeding shellfish/bivalves and other sea foods, harvested in polluted waters are consumed, much of it raw or lightly steamed. A number of scientific studies have shown that swimmers swallow significant amounts of polluted seawater and can become ill with gastrointestinal and respiratory diseases from the pathogens they ingest. Based on risk assessments from the World Health Organization (WHO) and academic research sources the present study has made an estimate that globally, each year, there are in excess of 120 million cases of gastrointestinal disease and in excess of 50 million cases of more severe respiratory diseases caused by swimming and bathing in wastewater-polluted coastal waters. Filter-feeding shellfish/bivalves, which are often harvested from wastewater-polluted areas of the sea, can effectively filter out and concentrate the microbial pathogens in the seawater. It can be roughly estimated that annually there are some 4 million cases of infectious hepatitis A and E (HAV/HEV), with some 40 thousand deaths and 40 thousand cases of long-term disability, mainly chronic liver damage, from consuming raw or lightly steamed filter-feeding shellfish/molluscs harvested globally from polluted coastal waters. The total global health impact of the thalassogenic diseases--human infectious diseases associated with pathogenic microorganisms from land-based wastewater pollution of the seas--is estimated to be about 3 million 'disability-adjusted life years' (DALY)/year, with an estimated economic loss of some 12 billion dollars per year. Due to the preliminary nature of the estimates in this study it is appropriate to assume that all of the above figures are no more than first approximations and that the true figures may be 50% higher or lower. Nevertheless, it is the author's belief that this study indicates that wastewater pollution of the sea results in a multi-billion dollar per year health burden and that preventing wastewater pollution of the sea is worthy of inclusion on the global agenda of marine pollution prevention and control.

Microbiological surveys were carried out on marine sands and sediments collected at a sandy beach along a coastal area close to Rome, Italy. Low densities of faecal indicator bacteria were recovered, and among them enterococci outnumbered the coliforms. The group of staphylococci was in a fairly constant concentration throughout the period of sampling. Some statistically significant correlations were calculated between yeasts and moulds, Escherichia coli and enterococci and between the latter and Clostridium spores. The data obtained could be a reference point for further studies.

Unlabelled: AIMIS: Draft WHO guidance is likely to suggest a calculated 95th percentile method, rather than percentage exceedence, in assessing compliance of bathing waters with microbiological standards. This study set out to determine whether this was an appropriate development., Methods and Results: A series of Monte Carlo studies compared five non-parametric methods for calculating the 95th percentile with the parametric method and compares results with percentage exceedence. It is shown that the Hazen method gives the closest proximity to the parametric method for calculating 95th percentile values. However, the difference between 95th percentile results and percentage exceedence, as currently used, is trivial compared to uncertainty due to sample variation., Conclusions: It is concluded that a calculated 95th percentile for beach classification offers little advantage compared to percentage exceedence, other than offering a false sense of certainty. Furthermore, the additional calculation needed in determining 95th percentile values will demand electronic calculation, increase the chance of calculation errors and make the results less understandable to beach managers and the general public., Significance and Impact of the Study: This study should encourage the European Commission to keep percent compliance rather than calculation of 95th percentiles in any new bathing water directive.

The EU Bathing Water Directive with a life of 25 years (EEC, 1976) has contributed significantly to the improvement of the quality of coastal recreational waters throughout Europe and has successfully protected public health. Improvement of the standards of living and general public demands has made it necessary to consider updating it (EU, 1994) introducing important changes in microbiological parameters. Measurement of microbial pollution is of primary importance to this new proposal, as is to the regulatory schemes introduced by the very recent 'Annapolis Protocol' (WHO/US EPA, 1999). This report discusses the microbiological aspects of the health-related management of bathing seawater in the context of the scientific information available from epidemiological and microbiological studies.

The large Oder (Szczecin) Lagoon (687 km2) at the German-Polish border, close to the Baltic Sea, suffers from severe eutrophication and water quality problems due to high discharge of water, nutrients and pollutants by the river Oder. Sewage treatment around the lagoon has been very much improved during the last years, but large amounts of sewage still enter the Oder river. Human pathogenic viruses generally can be expected in all surface waters that are affected by municipal sewage. There is an increasing awareness that predisposed persons can be infected by a few infective units or even a single active virus. Another new aspect is, that at least polioviruses attached to suspended particles can be infective for weeks and therefore be transported over long distances. Therefore, the highest risk of virus inputs arise from the large amounts of untreated sewage of the city of Szczecin (Poland), which are released into the river Oder and transported to the lagoon and the Baltic Sea. Summer tourism is the most important economical factor in this coastal region and further growth is expected. Human pathogenic viruses might be a serious problem for bathing water quality and sustainable summer tourism. The potential hazard of virus infections along beaches and shores of the Oder lagoon and adjacent parts of the Baltic Sea is evaluated on the basis of model simulations and laboratory results. We used two scenarios for the Older Lagoon considering free viruses and viruses attached to suspended particle matter. The spatial impact of the average virus release in the city of Szczecin during summer (bathing period) was simulated with a hydrodynamic and particle tracking model. Simulations suggest that due to fast inactivation, free viruses in the water represent a risk only in the river and near the river mouth. On the other hand, viruses attached to suspended matter can affect large areas of the eastern, Polish part of the lagoon (Grosses Haff). At the same time the accumulation of viruses on suspended particulate matter increases the likelihood of an infection after incorporation of such a particle. There is no evidence, that there is a risk of virus infections in the western part of the lagoon (Kleines Haff) or along the outer Baltic Sea coast.

Monitoring was carried out during summer 1997 along a selected area of the Tyrrhenian coast near the Tiber river mouth. Fifty-eight seawater samples, collected from 19 stations, were examined for coliforms, streptococci, Enteroviruses, Salmonellae, coliphages, Bacteroides fragilis phages, Pseudomonas, alophilic Vibrios, Aeromonas and yeasts. Salmonellae and coliphages were isolated in 3 and 12 out of 58 samples, respectively. Enteroviruses and Bacteroides fragilis phages were not isolated. Reoviruses were isolated only from 2 out of 58 samples. A limited number of samples of the northern stations located near the Tiber and other river mouths exceeded the guide values for bathing water by the EU Directive. All the southern stations, located near canals, were of very good microbiological quality. Pseudomonas, Vibrio, Aeromonas and yeasts were isolated from all stations and their values in 100 ml of seawater were 10-10(6), 10-10(6), 0-10(6) and 1-10(3), respectively. An extensive disinfection practice carried out on domestic wastes, which are discharged in rivers and canals, probably brought pollution levels of most stations to values within the bacterial standards. The spread of Pseudomonas, Aeromonas, etc. showed that all the coastal area studied was characterized by the presence of organic matter coming from land that can support the presence of opportunistic pathogens and other microbial flora.

The survival of fecal coliforms, fecal streptococci, Salmonella enteritidis and Staphylococcus aureus in sea water (35@1000 salinity) in the dark and at room temperature was evaluated. Staphylococcus aureus has been regarded for a long time as the new parameter to add to the classic ones in order to define the quality and suitability to recreational use. At the sperimental condition considered the survival of fecal coliforms, fecal streptococci, Salmonella enteritidis, and Staphylococcus aureus resulted equal to 48 h, 88 h, 56 h, and 96 h respectively. Fecal coliforms resulted the most sensitive bacteria to osmotic shock while Staphylococcus aureus the most adaptable species. Our results seem to indicate the opportunity of reconsidering the microbiological parameters used for the control of beach water.

Maintenance of the microbiological quality of water has been used as an important means of preventing waterborne disease throughout the twentieth century. The commonest microbiological tests done on water are for coliforms and Escherichia coli (or faecal coliform). This paper reviews the legislative and other guidance for microbial standards in drinking and bathing waters and considers evidence for the relationship between the microbiological quality of water and risk to human health. In the past measures of the microbiological quality of water correlated well with risks of acquiring gastrointestinal disease. More recent work suggests that gastrointestinal disease is more strongly associated with the presence of enterococci than of E. coli. New diseases such as cryptosporidiosis have been shown to cause outbreaks of waterborne disease when levels of conventional microbiological parameters are satisfactory. In response to this, and because of failure of prosecution in one outbreak, the United Kingdom (UK) Government has introduced new legislation that requires water providers to perform a risk assessment on their water treatment facilities and to implement continuous monitoring for cryptosporidium. A new European directive on drinking water has been introduced and legislation on cryptosporidium in drinking water has been proposed in the UK.

A series of investigations are underway which have quantified the contribution of faecal indicators delivered to nearshore coastal waters from the sewerage system and riverine inputs. Studies have been completed in Jersey, Staithes, Yorkshire, South Wales and the North-west. The research protocols have involved quantification of high and low flow faecal indicator delivery from the sewerage system and riverine sources as well as construction of nonpoint source models designed to predict faecal indicator delivery from diffuse, catchment sources. These investigations suggest a dynamic, but predictable, balance between inputs from the sewerage system and from 'catchment' sources. The sewerage system dominates during low flow conditions but is often overtaken by riverine inputs during high flow conditions after rainfall. Many bathing beach locations exhibit non-compliance after rainfall when stream inputs, rather than sewerage inputs, commonly dominate. The implications of this input pattern is that routine monitoring data may not provide information relevant to new infrastructure planning designed to achieve bathing beach compliance. This suggests that the present scientific information base is insufficient to underpin the extensive UK infra-structure investment programmes designed to ensure compliance with existing EU Directive 76/160/EEC standards. Furthermore, results to date, suggest that management attention must expand from its historical focus on infra-structure provision to incorporate diffuse sources of faecal indicator loading which present a new set of management and modelling challenges., (1998 Society of Applied Microbiology.)

Morecambe's three EU designated bathing beaches frequently fail the EU directives, even after a state of the art sewage treatment plant has become operational. We have been using conventional microbiology to look at the seasonality and distribution of indicator and pathogenic bacteria in Morcambe Bay and using molecular methods (polymerase chain reaction (PCR) and pulse field gel electrophoresis (PFGE)) to investigate the pathways by which pathogens reach the bathing waters. We will present data for Morecambe Bay which show that: 1. Failures and passes appear to be associated with the prevailing climatic conditions. 2. Indicator bacteria may not always be derived from sewage effluents. 3. Not all pathogens are distributed in the same way as indicator bacteria. 4. Pathogens such as Campylobacter are as likely to come from birds as from sewage., (1998 Society of Applied Microbiology.)

Since the introduction and strict application of EC guidelines on the monitoring of bathing waters began in Lower Saxony in 1989, it has been possible for the first time to reach a comprehensive evaluation of the water quality on the North Sea coast and in the rivers and lakes of this state. The 7648 samples which were analysed in this period produced the most favourable results on the East Friesian Islands, followed by the vast majority of the mainland bathing resorts and some lakes. On the lower stretches of the River Weser and in a few lakes levels were registered at times which exceeded the limits to such an extent that bathing was impossible. In 1991 extreme germination of total coliform bacteria was observed for the first time, presumably due to eutrophic conditions in combination with high water temperatures.

As the first phase of a major programme to develop epidemiologically derived recreational water quality criteria for South Africa, a preliminary epidemiological-microbiological study was conducted in Cape Town during February and March 1990. Serial trials were carried out at a clean and at a relatively polluted beach over weekends. Participants were recruited at the beach, at which time information on swimming status and sociodemography was obtained. This provided for a beach-going but non-swimming control group. Symptoms which developed subsequent to the beach visit were obtained by follow-up telephone interviews conducted 3-4 days later. Water samples collected on trial days both before and during maximum swimming activity, were analysed for enterococci, faecal coliforms, staphylococci, coliphages and F-male-specific bacteriophages. Significant differences in the indicator levels at the beaches were observed. An excess in gastro-intestinal, respiratory and skin symptoms were found among swimmers relative to non-swimmers at the polluted beach. Although not statistically significant, the results are suggestive of a relationship between swimming-associated illness and water quality. The study demonstrated the feasibility of the methodology and the results of the overall programme will form the basis for the development of epidemiologically derived recreational water quality criteria for South African beaches.

During the summer season of 1989 about 222 samples of bathing water (Northsea, Baltic Sea and inland waters) were investigated, i.e. 2 times 1998 dilution tubes (1501 positive) were tested. Results with BRILA-MUG and lactose-bouillon were compared and additional 97 samples were tested with one respectively three colonies by confirmative tests. -- The BRILA-MUG one-tube-test (gas, fluorescence and indol) has as expected larger numbers of total coliforms (GC) and faecal coliforms (FC) in comparison with corresponding numbers for E. coli and coliform bacteria according to German law for drinking water (TrinkwV). -- BRILA-MUG and lactose-bouillon with the same identification mode according to "TrinkwV" has corresponding results concerning E. coli and coliform bacteria. -- Following the identification mode according to "TrinkwV" the total coliforms (GC/gas in BRILA-MUG) depending on the origin proved 60-80% as coliform bacteria. Additional API-tests showed that the other bacteria are coliform bacteria too or bacteria which can be considered as indicators for water pollution. -- Faecal coliforms (FC/fluorescence and indol-positive) depending on the origin proved 70-90% as E. coli, if following the identification mode according to "TrinkwV". Using 3 instead of 1 colony per positive dilution tube for identification the positive results increased approximately by 9%. 15% of negative results with the identification mode according to "TrinkwV" proved as E. coli-positive with identification according to API-system, i.e. the corresponding rate of E. coli-positive tubes will therefore be higher than shown above. The BRILA-MUG one-tube-test in connection with the MPN-method can be used successfully to determine the number of total and faecal coliforms according to the EEC-directive for bathing waters. The test needs only a minimum of material and also a minimum of laboratory staff. Differences between this test and other more extensive tests with several biochemical identification steps are negligible. The work load for bathing water tests would not be justified in this case.

A number of bacterial, viral and other diseases can be contracted by man through exposure to sewage-polluted bathing-water or beach sand. The increasing use of the sea for recreation has led to major concern regarding health hazards to both local and tourist populations. Epidemiological studies attempting to correlate microbiological water quality with health effects have produced different results, leading to a wide variation in recreational water quality criteria and standards applied, and to considerable controversy regarding their implementation. The Mediterranean provides a good example of a problem region where health risks are accentuated as a result of high utilization of bathing areas coupled with long exposure periods. Coastal pollution by sewage is still a major concern and control measures vary considerably. A number of microbiological/epidemiological studies have been carried out since 1953 in an attempt to define the levels of risk following exposure to different concentrations of bacteria in bathing waters. Most of these have been prospective studies whose design involved subject recruitment on the beach itself, classification of swimmers on the basis of immersion of the head in the water, and follow-up interviews after 7-10 days, together with a system for validation of gastrointestinal symptomatology. Practically all studies showed higher morbidity among bathers as compared to non-bathers, but correlation between specific symptoms and bacterial indicator concentrations varied considerably. On the basis of the 1972-1978 Cabelli Environmental Protection Agency (EPA) study in the United States of America, later developed by EPA into a recommended health-effects criterion for marine recreational waters, one would expect 25-40 gastrointestinal cases per 1,000 persons exposed to seawater containing 100 enterococci per 100 ml. Extrapolation of these figures to annual bathing populations indicates the potential magnitude of the problem. Much more work is needed however before a satisfactory dose-response relationship is obtained, principally because of confounding factors inherent in all studies carried out so far, which still require a solution.

Regarding the quality of natural recreational water for bathing purposes, the limit values of E. coli and coliforms, faecal coliforms and totalcoliforms, respectively, laid down by the Council of the European Community, differ considerably from those prescribed by some Land Governments of the Federal Republic of Germany and by the DIN Standard Regulation No. 19643 entitled 'Processing and Disinfection of Water in Swimming Pools and Basins in Public Baths'. It must be concluded by virtue of hygienically plausible considerations, as well as for juridical reasons, that only the limit values of the EC-Code of Practice are authoritative, whereas standards of the DIN 19643, especially in respect of E. coli and coliforms, differing from the limit values of the EC-Code of Practice are not legally binding. Moreover, coliforms are not relevant for controlling swimming pools and basins in public baths. Staphylococcus aureus should therefore be investigated instead whereas other parameters such as E. coli, Pseudomonas aeruginosa, and total colony counts are good markers. However, the standards of these organisms as established by the DIN 19643 are more in line with technical practibility and biased aesthetics instead of the hygienically important prinicple of commensurability.

Findings are described from the second year of an epidemiological-microbiological study conducted at New York City beaches as part of the U.S. Environmental Protection Agency program to develop health effects-recreational water quality criteria. Symptomatology rates among swimmers (defined as immersion of the head in the water) relative to nonswimming but beach-going controls at a "barely acceptable" (BA) beach and a "relatively unpolluted" (RU) beach were examined. Data were collected by contacting family groups at the beach on weekends, obtaining information on bathing activity, and then questioning them by phone some 8--10 days later. In addition measurements were made for a number of potential water quality indicators. It was observed that the symptom rates, categorized as gastrointestinal (GI), respiratory, "other", and "disabling" (stayed home, stayed in bed, consulted a physician), were higher among swimmers than nonswimmers. As in the pretest conducted the previous year, the rate of GI symptoms was significantly higher among swimmers relative to nonswimmers at the BA but not the RU beach. Children, Hispanic Americans, and the low-middle socioeconomic groups were identified as the most susceptible portions of the population.

An improved mathematical model for bathing beach safety is proposed. It is derived by joining the probability of infection from a given dose (Poisson distribution and the probability of acquiring such a dose (lognormal distribution). Even in the absence of better clinical and epidemiological data, the model permits an assessment of relative risk from certain hazards and the design of more meaningful bacteriological standards for individual beaches.

The Danish bathing water control system as it has been worked out on the basis of the EEC Directive is described. According to the national tradition a standard for E. coli which is more stringent that the mandatory value in the directive has been maintained. Additionally water which has not distinctly been appointed as bathing water is protected against deterioration in the national legislation. Local authorities have been authorized to prohibit dogs on the beaches. Results from 1978 show that 16284 samples were taken from 1525 sampling points. Acceptable water quality was proved at 1292 stations. Only at 23 stations did local authorities completely prohibit bathing activities. The coast has been classified as excellent, good or unfit for recreational use. In fig. 1 a survey of water quality for the whole country is indicated. The use of coliforms as pollution does not essentially improve the evaluation of the hygienic condition of the water at least in the marine environment.