Harmful Algae News No. 48 - April 2014 · www.ioc-unesco.org/hab An IOC Newsletter on Toxic Algae and Algal Blooms IOC/WESTPAC Scientists Develop Technical Guidelines for Ciguatera Studies On 5-6 November 2013, an IOC/WEST- a strange odor or taste, and cooking rine Organisms, emphasizing the need PAC Training Workshop on Toxic Ma- fish does not inactivate the heat-stable for one regional standard method for rine Organisms was organized at the toxin. CFP studies. The two days workshop, University of Tokyo, Japan, with one of CFP is the most problematic algal with the contribution of invited Japa- its major objectives to develop regional poisoning syndrome, with reported nese experts on ciguatoxins and other technical guidelines on ciguatera stud- cases amounting to 20,000 – 30,000 per marine toxins, aimed to improve knowl- ies, drawing on experiences from Japan. year, but no effective management sys- edge on the present situation of CFP in Ciguatera Fish Poisoning (CFP or tem has been developed yet in the IOC/ Member States, and develop a regional Ciguatera) is a foodborne illness caused WESTPAC region. Despite the low num- technical guide on the collection of cigu- by eating certain reef fishes contaminat- ber of reported cases of CFP in the re- atera poisonings data, including clarifi- ed with ciguatoxins andGambierdiscus. its analogues gion, scientists are concerned that there cation of clinical symptoms, identifica- originally produced by toxic dinoflag- must be many unreported cases in the tion of possible causative food, sample ellates of the genus region, and reports may increase in the collecting for screening for toxicity and Large reef-dwelling fish in tropical and near future, given that CFP occurs main- toxin identification. sub-tropical waters accumulate marine ly in tropical and subtropical coral area. Dao Viet Ha, Chair IOC/WESTPAC/TMO Project, Institute of Oceanography, Vietnam toxins by eating toxic algae growing on “We must provide scientifically reli- Email: [email protected] coral reefs, and are most likely to cause able information to prevent and reduce ciguatera poisoning. CFP is difficult to the impact of CFP” said Dr. Dao Viet Ha, prevent as ciguatoxic fish do not carry WESTPAC Project Leader on Toxic Ma- Participants in the 3rd IOC/WESTPAC-TMO training workshop in Japan, 5-6 Nov. 2013. First report of an Ostreopsis ovata bloom on Abruzzo coast (W Adriatic) associated the western coast of Italy (Tyrrhenian Sea) in the 1980s [10]. In the last dec- with human respiratory intoxication ade, massive blooms of this species have become more frequent, above all in the Tyrrhenian and Ligurian Seas, Os- causing death of benthic organisms treopsisAt the endovata of August 2013, the first treopsidaceae: cells are narrow, ovate and human health problems such as bloom of the benthic dinoflagellate in dorso-ventral view with biconvex, respiratory difficulties and skin irrita- occurred on the coast drop-shaped theca, scattered pores and tion [11]. Over the last decade, people of “Trabocchi”, Chieti Province, in the eight sulcal plates [3]. The life cycle in- swimming or exposed to marine aero- Abruzzo Region, Western Adriatic Sea. cludes a resting stage, probably a hyp- sols along the Tyrrhenian and Adriatic The bloom formed a brown velvet mat nozygote [4]. This species is occasion- coasts of the Mediterranean Sea have covering natural and artificial rocks, ally planktonic but generally benthic on reported a range of symptoms (rhinor- seaweed thalli,O. and ovata mollusc shells, and macroalgae, rocks, sediment or detritus rhoea, bronchoconstriction,O. ovata coughing, persisted for about 1 month. By the end aggregates, and forms a mucilaginous fever, dermatitis) associated with high of September, was only found matrixOstreopsis within ovata which the solitary cells densities of . In the early 2000s, sporadically. This species was first re- can move [5]. the most important inhalation intoxi- ported on the Abruzzo coast in summer O. ovata produces palytoxin- cations were observed in Italy in 2001 2008 [1]. Since then, it has been quite like (PTX) compounds [6]. Blooms of [12] and in 2005 [13], and in Spain in abundant every year, but it had not pre- can cause hypoxia, anoxia and 2004 and 2006 [14], affecting more viously formed a bloom nor raised con- benthic invertebrate kills by forming than 200 personsOstreopsis each time (swim- cerns. Here we describe the first Ostreevent- mucilaginous layers hosting thousands mers, beach goers, local residents). opsiswith human intoxications and mussels/ of cells covering both biotic and abiotic Since then, blooms has been octopus mortality relatedOstreopsis to an substrates [7]. In addition, formation of detected in several northern and south- bloom in Abruzzo coastal wa- toxic aerosolsOstreopsis by wave action can pro- ern Mediterranean countries [15]. ters. The distribution of was duce asthma-like symptoms. In temper- The Trabocchi coast is characterizedO. ovata mostly observed at three rocky beaches, ate zones, blooms are asso- by shallow rocky coves with pebbly bot- where several cases of human intoxica- ciated with intoxication by inhalation toms. The appearance of the tionOstreopsis were recorded, from late August to [8], skin irritation by contact, and mass bloom led to intense sampling; it was mid-September 2013. mortalities of invertebrates. Intoxica- mostly present off three rocky beaches, species are benthic tion by ingestion has not been reported, Rocca San Giovanni, Fuggitella and Fos- dinoflagellates generally recorded in even when PTX and/or analogs have sacesia (Fig.1). Sampling was carried tropical and subtropical seas, but the alreadyO. ovata been found in seafood by chem- out from 29th August to 13th Septem- worldwide records of this genus have ical or toxicological analysis [9]. ber when respiratory problems were Ostreopsisincreased markedly in the last decade has been recorded in the reported and poisoning occurred. The and this trend is likely to continue [2]. Mediterranean since the 1970s on water column and different substrates belongs to the family Os- French coasts. It was first detected on were sampled for phytoplankton and chemical-physical analysis. Samples of macrophytes (15-25 gr fresh weight) were collected from depths between 0.5 and 1.5 m, placed in plastic bottles with filtered seawater and kept in the dark. A surface water sample was im- mediately fixed with Lugol’s solution to estimate the abundance of epiphytic dinoflagellates-1 in the water column (in cells L ). Macrophyte samples were shaken for more than one minute to de- tach epiphytic cells. The material was then passed through 250 and 100 μm mesh sieves to remove large particles, and was fixed with Lugol’s solution. Epiphytic-1 abundance was expressed in cells gr fresh weight of macrophyte (fwm). The fixed material was settled in 2–10 ml chambers for the appropriate time according to Utermöhl’s method. Fig. 1. Trabocchi coast (Adriatic Sea – Abruzzo Region) and location of sampling sites The highest water column concenOstre- trations coincided with maximum epi- phytic abundance.HARMFUL The ALGAEhighest NEWS NO. 48 / 2014 2 Fig. 2. Towns affected by bloom where beaches were closed for bathing: (a) Rocca San Giovanni and (b) Fossacesia. The brown biofilm of the epiphytic : c) on rocks and d) inside flask. Light microscopy photographs of bloom: e) and f) field samples with high cell counts, 50x magnification,O. scale ovata bar = 100 µm and 400x magnification, scale bar = 50 µm respectively. g) Scanning electron micrographs of from isolatedO. ovata strain: epithecal view with pore plate (Po) short and straight (arrows),O. scale ovata bar = 5 µm. h) LM epifluorescence of : epithecal view with plates Po and 1’, 1000x magni fication, scale bar = 10 µm. O. ovata O. ovata opsis 6. Ciminiello P et al 2006. Anal Chem 78: 6153–6159 concentration5 -1 recorded reached4 cal media (newspapers and television). 7. Congestri R et al 2006. Harmful Algal News 32: 11–12 5.28 x -110 cells g fwm and 9.21 x 10 A week later after a weak gale, sam- cells L in the water column on 6th pling on September 13th at Fossacesia 8. Gallitelli M et al 2005. JAMA 293: 2599– O. ovata O. ovata 2600 September 2013 at Fossacesia during revealed the highest concentration of 4 9. Aligizaki K et al 2008. Toxicon 51: the bloom maximum, with 25 -1 . There were then 8.35 x 10 418–427 °C water temperature,-1 34.3 psu salinity cells 3g fwm-1 on macrophytes and 7.28 10. Lenzi Grillini C & Lazzara L 1980. Giorn Bot It 114: 199–215 and 6.7 mg L dissolved oxygenO. (106% ovata x 10 cells L in the water column, 24 saturation). °C water temperature, 33.3 psu salinity 11. Bianco I et al 2006. Biol Mar Medit 13: -1 Ostreopsis ovata 947–950 During the period of the and 7.0 mg L dissolved oxygen (108% 12. Casavola N et al 2005. Rapporti ISTISAN bloom, there was strong coloration of saturation). Thus con- 05/29: 92-97 the water and a prominent biofilm on centrations had greatly decreased; but 13. Brescianini C et al 2006. Eurosurveil- rocks. The water had a strange smell the number of degraded cells increased. lance 11: 3040 like eggs, and dead mussels and octo- The water was still smelly and slightly 14. Vila M et al 2008. Proc 12th Intern Conf on Harmful Algae, pp. 334-336 pus were also noticed during the bloom. brownish and nutrient concentrations 15. Totti C et al 2010. Harmful Algae 9: 233- Thirty two cases of human intoxication Referencesalmost unchanged. 239. occurred, ten of whom required medical 1. Ingarao C et al 2009. Harmful Algal assistance. Symptoms included severe News 39: 4-5 Authors pain in the trachea, nausea, breathing 2. Rhodes L 2011. Toxicon 57 (3): 400–407 Cristina Ingarao C & Tommaso Pagliani, Environmental Science Centre, Fondazione problems, vomiting and fever.