A Citizen Science Platform to explore Ostreopsis blooms and their impacts

Abstract

Since the late 90s, blooms of the tropical genus Ostreopsis in certain temperate beaches have been related to respiratory symptoms, skin and mucosa irritation in humans. People exposed to marine aerosol for several hours reported mild respiratory irritations (rhinorrhea, pharyngeal pain, cough), general malaise, headache, fever (¿38ºC) and eye irritation. Some of these symptoms and/or dermatitis were also noted after swimming. There are many uncertainties concerning the human health impacts associated to Ostreopsis blooms. This is due, in part, to the fact that samplings for Ostreopsis cells in the benthos are not usually included in monitoring programs for water quality in beaches, and when done, they rarely coincide (time, space) with human health problems recorded by epidemiologists. Furthermore, affectations are underreported due to the lack of specificity of the health symptoms, which normally disappear within a few hours without particular treatment when people move away from the affected Ostreopsis bloom area. Recently, parallel epidemiology and ecology studies in a hot spot area in the NW Mediterranean (2013-2017) revealed that symptoms occurred within a particular physiological phase of the bloom (mainly in the transition from exponential to the stationary phase) and were not noticed during long periods of high cell abundances. With the aim to explore the presence of Ostreopsis blooms in the Mediterranean coast and to detect its potential health impacts, we launched a pilot platform of Citizen Science in August 2017 through two outreach webpages. Technical cards with basic information on Ostreopsis blooms were displayed in the two websites. Images of water discolorations, floating aggregates and foams, and macroalgae communities covered by the mucilaginous biofilms produced by Ostreopsis helped to identify the massive presence of the microalgae by beach users when swimming or snorkelling. People were invited to take pictures, send them to the website and provide basic environmental conditions (i.e. water temperature, meteorological and sea conditions, habitat description, location, etc.). Particular information was requested concerning the submarine mucilage (covering the macroalgae, rocks or sand) and simultaneous surface foams (colour, size, presence of macroalgal fragments). Finally, citizens were asked whether they had noticed any irritant symptom on eyes, nose and skin. In this case, they were invited to contact us through email and further private communication (to guarantee personal data preservation) with us was established to get more insight into the health affectation. In this way we identified the presence of Ostreopsis in a new area where beach goers noticed irritant symptoms. With this Citizen Science Platform, people are empowered and share key information with sea researchers at local scale. This approach can be useful for other HAB events worldwide