Vol. 114, No. 5 EnvironewsOpen AccessDiving Hazards Unmasked: Estimating Infection Risk from Pathogen Exposureis accompanied byA Survey of Diving Behavior and Accidental Water Ingestion among Dutch Occupational and Sport Divers to Assess the Risk of Infection with Waterborne Pathogenic Microorganisms Nancy Bazilchuk Nancy Bazilchuk Search for more papers by this author Published:1 May 2006https://doi.org/10.1289/ehp.114-a304aAboutSectionsPDF ToolsDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InReddit Most recreational water quality standards are aimed at protecting beachgoers against accidental ingestion of or skin contact with water contaminated by fecal material. But the increased popularity of water sports such as kayaking, surfing, and diving, which often occur far from regulated bathing beaches, raises the question of the water-related health risks these sports entail. Now two researchers at the National Institute of Public Health and the Environment in the Netherlands have attempted to answer this question for divers [EHP 114:712–717; Schijven and Husman]. The study is the first to establish estimates of how much water divers swallow, figures that can be used in calculating health risks involved with waterborne pathogen exposure during diving.The researchers used detailed questionnaires to ask occupational and sport divers about the number and duration of dives they made in ocean, coastal, and freshwater areas; whether a known pollution source was nearby; the type of diving mask worn (which affects the amount of water swallowed); and the amount of water typically swallowed per dive. Five equivalents enabled divers to estimate how much water they swallowed: nothing, a few drops (an average of 2.75 milliliters [mL]), a shot glass (25 mL), a coffee cup (100 mL), or a soda glass (190 mL). The questionnaire also asked respondents to detail past health complaints, including diarrhea, vomiting, nausea, and eye, skin, and ear problems.Then the researchers calculated the risk of infection per dive and per year based on the volume of swallowed water reported and pathogen concentrations. Campylobacter jejuni and enteroviruses were used for the analysis; concentrations for these organisms in different kinds of surface waters were taken from the literature, and concentration distributions constructed.The infection risks for C. jejuni were generally an order of magnitude higher than those for enteroviruses. For occupational divers, the greatest per-dive mean risk of infection was calculated at 2.8% in coastal waters near a sewage discharge. For sport divers wearing ordinary diving masks, the greatest mean risk was seen in freshwater recreational waters, where there was a 1.5% per-dive risk and a 25% per-year risk of getting an infection. The risk was about 10 times lower when sport divers wore full face masks.Although occupational divers usually have the protection of a full face mask or diving helmet, they are far more likely than sport divers to dive in contaminated conditions—for example, to assess damage to underwater sewage pipes. They also tend to stay underwater longer. Thus, the chance for exposure goes up.These relatively high infection risks may explain why 80% of the divers surveyed reported at least one of the health complaints listed on the questionnaire during the course of one year. The authors recommend that divers wear full face masks or helmets when diving in potentially contaminated waters, and that they stay informed about fecal contamination in diving areas.What lies beneath.A new study estimates divers’ risk of developing infections when diving in fecal-contaminated waters.FiguresReferencesRelatedDetailsRelated articlesA Survey of Diving Behavior and Accidental Water Ingestion among Dutch Occupational and Sport Divers to Assess the Risk of Infection with Waterborne Pathogenic Microorganisms16 February 2006Environmental Health Perspectives Vol. 114, No. 5 May 2006Metrics About Article Metrics Publication History Originally published1 May 2006Published in print1 May 2006 Financial disclosuresPDF download License information EHP is an open-access journal published with support from the National Institute of Environmental Health Sciences, National Institutes of Health. All content is public domain unless otherwise noted. Note to readers with disabilities EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact [email protected]. Our staff will work with you to assess and meet your accessibility needs within 3 working days.