Basin-specific changes in filamentous cyanobacteria community composition across four decades in the Baltic Sea

Almost every summer, dense blooms of filamentous cyanobacteria are formed in the Baltic Sea. These blooms may cause problems for tourism and ecosystem services, where surface accumulations and beach fouling are commonly occurring. Future changes in environmental drivers, including climate change and other anthropogenic disturbances, may further enhance these problems. By compiling monitoring data from countries adjacent to the Baltic Sea, we present spatial and temporal genus-specific distribution of diazotrophic filamentous cyanobacteria (Nostocales) during four decades (1979–2017). While the summer surface salinity decreased with a half up to one unit, the surface temperature in July-August increased with 2–3 °C in most sub-basins of the Baltic Sea, during the time period. The biovolumes of the toxic Nodularia spumigena did not change in any of the sub-basins during the period. On the other hand, the biovolume of the non-toxic Aphanizomenon sp. and the potentially toxic Dolichospermum spp. increased in the northern parts of the Baltic Sea, along with the decreased salinity and elevated temperatures, but Aphanizomenon sp. decreased in the southern parts despite decreased salinity and increased temperatures. These contradictory changes in biovolume of Aphanizomenon sp. between the northern and southern parts of the Baltic Sea may be due to basin-specific effects of the changed environmental conditions, or can be related to local adaptation by sub-populations of the genera. Overall, this comprehensive dataset presents insights to genus-specific bloom dynamics by potentially harmful diazotrophic filamentous cyanobacteria in the Baltic Sea. Highlights • Biovolumes of bloom-forming cyanobacteria during four decades in the Baltic Sea. • Aphanizomenon sp. has increased with decreased salinity in the Bothnian Sea. • Dolichospermum spp. has increased with temperature in Bothnian Sea. • The total biovolume of Nostocales has decreased in the Southern Baltic Proper. • The biovolume of the toxic Nodularia spumigena has not changed since the 1980s

Harmful algal blooms and their effects in coastal seas of Northern Europe

Highlights • Fish mortalities due to harmful algae cause substantial economic and social costs for the fish farming industry in the northeastern Atlantic, North Sea and adjacent European waters • Toxin syndromes associated with Diarrhetic Shellfish Toxins and Paralytic Shellfish Toxins and their regulation have the most profound effect on the bivalve aquaculture industry in the northeastern Atlantic region • Cyanobacteria and cyanotoxins are mainly problems in brackish water areas, particularly in the Baltic Sea • Emerging threats to the shellfish and finfish industries include the known presence of the phycotoxins azaspiracids and goniodomins • The IOC-ICES-PICESHAEDAT contains time-series baseline information on harmful algal events in EuropeHarmful algal blooms (HAB) are recurrent phenomena in northern Europe along the coasts of the Baltic Sea, Kattegat-Skagerrak, eastern North Sea, Norwegian Sea and the Barents Sea. These HABs have caused occasional massive losses for the aquaculture industry and have chronically affected socioeconomic interests in several ways. This status review gives an overview of historical HAB events and summarises reports to the Harmful Algae Event Database from 1986 to the end of year 2019 and observations made in long term monitoring programmes of potentially harmful phytoplankton and of phycotoxins in bivalve shellfish. Major HAB taxa causing fish mortalities in the region include blooms of the prymnesiophyte Chrysochromulina leadbeateri in northern Norway in 1991 and 2019, resulting in huge economic losses for fish farmers. A bloom of the prymesiophyte Prymnesium polylepis (syn. Chrysochromulina polylepis) in the Kattegat-Skagerrak in 1988 was ecosystem disruptive. Blooms of the prymnesiophyte Phaeocystis spp. have caused accumulations of foam on beaches in the southwestern North Sea and Wadden Sea coasts and shellfish mortality has been linked to their occurrence. Mortality of shellfish linked to HAB events has been observed in estuarine waters associated with influx of water from the southern North Sea. The first bloom of the dictyochophyte genus Pseudochattonella was observed in 1998, and since then such blooms have been observed in high cell densities in spring causing fish mortalities some years. Dinoflagellates, primarily Dinophysis spp., intermittently yield concentrations of Diarrhetic Shellfish Toxins (DST) in blue mussels, Mytilus edulis, above regulatory limits along the coasts of Norway, Denmark and the Swedish west coast. On average, DST levels in shellfish have decreased along the Swedish and Norwegian Skagerrak coasts since approximately 2006, coinciding with a decrease in the cell abundance of D. acuta. Among dinoflagellates, Alexandrium species are the major source of Paralytic Shellfish Toxins (PST) in the region. PST concentrations above regulatory levels were rare in the Skagerrak-Kattegat during the three decadal review period, but frequent and often abundant findings of Alexandrium resting cysts in surface sediments indicate a high potential risk for blooms. PST levels often above regulatory limits along the west coast of Norway are associated with A. catenella (ribotype Group 1) as the main toxin producer. Other Alexandrium species, such as A. ostenfeldii and A. minutum, are capable of producing PST among some populations but are usually not associated with PSP events in the region. The cell abundance of A. pseudogonyaulax, a producer of the ichthyotoxin goniodomin (GD), has increased in the Skagerrak-Kattegat since 2010, and may constitute an emerging threat. The dinoflagellate Azadinium spp. have been unequivocally linked to the presence of azaspiracid toxins (AZT) responsible for Azaspiracid Shellfish Poisoning (AZP) in northern Europe. These toxins were detected in bivalve shellfish at concentrations above regulatory limits for the first time in Norway in blue mussels in 2005 and in Sweden in blue mussels and oysters (Ostrea edulis and Crassostrea gigas) in 2018. Certain members of the diatom genus Pseudo-nitzschia produce the neurotoxin domoic acid and analogs known as Amnesic Shellfish Toxins (AST). Blooms of Pseudo-nitzschia were common in the North Sea and the Skagerrak-Kattegat, but levels of AST in bivalve shellfish were rarely above regulatory limits during the review period. Summer cyanobacteria blooms in the Baltic Sea are a concern mainly for tourism by causing massive fouling of bathing water and beaches. Some of the cyanobacteria produce toxins, e.g. Nodularia spumigena, producer of nodularin, which may be a human health problem and cause occasional dog mortalities. Coastal and shelf sea regions in northern Europe provide a key supply of seafood, socioeconomic well-being and ecosystem services. Increasing anthropogenic influence and climate change create environmental stressors causing shifts in the biogeography and intensity of HABs. Continued monitoring of HAB and phycotoxins and the operation of historical databases such as HAEDAT provide not only an ongoing status report but also provide a way to interpret causes and mechanisms of HABs

Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe

Periodic health examinations during a pandemic

Introduction: The coronavirus pandemic has changed daily lives. These changes affect many aspects of lives including periodic health examinations. Specialists warn that in the era of the pandemic people abandon examinations. This is a very dangerous phenomenon, which can negatively affect health and general well-being. The aim of this study was to determine the frequency of periodic health examinations during the pandemic period including the use of telephone advice services.Material and methods: The study was carried out in March 2021 among 147 people (120 women and 27 men), in the age range of 18-76 years. The study was carried out by the method of diagnostic survey, with the use of questionnaire technique (authors’ questionnaire). Questions included knowledge of prevention, frequency of periodic health examinations, and health services received by the respondents during the pandemic. Analysis of the survey results provided information on current health problems, time of diagnosis, and course of treatment to date. Results: During the pandemic, the majority of respondents had the opportunity to use a telephone advice, with women more likely to use the telephone advice than men (64.2% vs. 37.0%; p = 0.010). 36.9% of the respondents were satisfied with the service. The main reasons for dissatisfaction with the telephone advice included: inability to examine (33.3%), short telephone advice time (24.2%), misdiagnosis or ineffective treatment (21.2%), long waiting time, difficult contact with the facility (15.2%). Among telephone advice users, 39.1% had chronic diseases; among non- telephone advice users, the percentage was lower at 18.3%. Telephone advice users were significantly less likely to say they did not have periodic health examinations or did not remember when they had them done compared to non- telephone advice users (p = 0.019).Conclusions: During the pandemic, the majority of respondents had the opportunity to use telephone advice. Only 1/3 were satisfied with the telephone advice, and the main reasons for dissatisfaction were as follows: inability to examine, short telephone advice time, misdiagnosis or ineffective treatment. Telephone advice users were significantly less likely to say they did not have periodic examinations or could not remember when they had them done compared to non-telephone advice users

Toxic <i>Nodularia spumigena</i> blooms in the coastal waters of the Gulf of Gdańsk: a ten-year survey

In the Baltic Sea, summer blooms of the filamentous, nitrogen-fixingcyanobacterium <i>Nodularia spumigena</i> are favoured by high P concentrationsat low N:P ratios and a salinity range of 5-13 PSU. The bloomsare initiated by calm and sunny weather, an elevated surfacewater temperature and thermal stratification. The mass occurrenceof <i>N. spumigena</i> in coastal waters is a matter of special concern,as the cyanobacterium produces nodularin, a potent pentapeptidehepatotoxin. In the Gulf of Gdansk, the large-scale occurrenceof <i>N. spumigena</i> was recorded for the first time in 1994. Bloomsof a similar intensity occurred in 2001, 2003 and 2004. Nodularinconcentrations in freeze-dried bloom samples varied from 0.01to 4.01 mg g^-1 d.w. In the coastal waters of the Gulf of Gdańsk,cell-bound nodularin concentrations in 2004 and 2005 attainedmaxima of 25852 ± 107 µg dm^-3 and3964 ± 125 µg dm^-3, respectively. Microscopic analysis revealedthe presence of diverse <i>N. spumigena</i> forms, with the dominance of curvedfilaments in bloom samples. The results of <i>in situ</i> studies and remotesensing measurements indicate a high frequency and intensity of cyanobacterialblooms in the Gulf of Gdańsk in the last ten years

Canthaxanthin in recent sediments as an indicator of heterocystous cyanobacteria in coastal waters

Summary: The mean share of heterocystous cyanobacteria in total chlorophyll-a production in coastal waters, based on cyanobacterial marker carotenoid and chloropigments preserved in recent sediments (0–5 cm, ca 30 years), has been studied in the Gulf of Gdańsk (southern Baltic) and for comparison in the Oslofjord/Drammensfjord (southern Norway). First of all, Baltic cyanobacteria, both from laboratory cultures and field samples, were analysed to select marker heterocysteous cyanobacteria carotenoids for sediments. The pigment relation to diatom percentages of different salinity preferences has been tested, to confirm origin of cyanobacteria. The results indicate that canthaxanthin is the best marker of heterocystous cyanobacteria in the southern Baltic Sea. These filamentous cyanobacteria inflow to the Gulf of Gdańsk from the open sea and their abundance has increased in the last thirty years, in comparison with previous time. In that period they made up ca 4.6% of the total chlorophyll-a production in the Gulf of Gdańsk. The estimate for Oslofjord, at the same assumptions, suggests that heterocystous cyanobacteria occurred there also (up to 5.8% of the total chlorophyll-a production), were of marine origin, but their abundance has decreased during the last thirty years. Such an estimate may be used in environmental modelling and can be applied to other coastal areas, once the marker pigments of the main cyanobacteria species have been identified, and the percentage of total chlorophyll-a produced in a basin, preserved in sediments, has been determined for such area. Keywords: Cyanobacteria, Carotenoids, Canthaxanthin, Gulf of Gdańsk (southern Baltic), Oslofjor

Ecology of toxic cyanobacteria

Eutrophication of waters bodies, as a consequence of human activities, results in the loss of biodiversity followed by massive appearance of cyanobacteria. In freshwater ecosystems, the blooms are mostly formed by the genera Microcystis, Planktothrix, Anabaena and Cylindrospermopsis; in brackish and marine waters Nodularia spumigena, Aphanizomenon flos-aquae and Trichodesmium can thrive under favorable conditions. Species belonging to the order Nostocales and Oscillatoriales live in filaments. The vegetative cells of Nostocales may differentiate into heterocytes and akinets. The order Chroococcales aggregates in colonies of different shape and size; they rarely produce akinets. Cyanobacteria have developed a wide range of adaptation mechanisms which enable them to inhabit different niches of aquatic ecosystems and out-compete other phytoplankton organisms. Due to N2 fixation, the filamentous and heterocytes forming species can grow in nitrogen depleted waters; gas vesicles are used to regulate buoyancy and adjust to optimal light intensity, while accessory pigments (phycocyanin, phycorytrin) enable them to absorb light in most efficient way. Growth of cyanobacteria is determined by a number of environmental factors, including water temperature, light intensity, ratio between nitrogen and phosphorus concentrations as well as the dynamics of water masses. Some species produce secondary metabolites harmful to humans and animals. The compounds show hepatotoxic, neurotoxic, cytotoxic and dermatotoxic activities. Cyclic oligopeptides, termed microcystins, are the most commonly occurring cyanobacterial toxins. Like other non-ribosomal peptides, they are synthesized by thiotemplate mechanism. From one water bloom both microcystin-producing and non-microcystin-producing strains can be isolated. In some studies relationship between microcystin production and the morphology of Microcystis has been revealed. It was also proved that microcystin concentration in bloom material mostly depends on the contribution of toxic genotype; it is also affected by environmental factors, but to a lesser extent. Exposure of aquatic animals to toxin-producing cyanobacteria leads to contamination of their tissues and organs. Microcystins and nodularin may accumulate in the organisms via ingestion, transdermal rout or by taking up directly from water in dissolved form. The toxins were detected in zooplankton, mussels, snails, fish and birds from freshwater and marine environments. In liver and viscera the concentration of the compounds was highest; they were also found in muscles, gonads, kidney, gills and in feather of birds. As polar compounds, cyanobacterial hepatotoxins are probably not biomagnified in aquatic food web. Some authors suggested that detoxication of aquatic organisms proceeds through formation of glutathion conjugates. The process is probably not complete, as microcystin and nodularin were detected in the animal tissues several months after the bloom of toxic cyanobacteria. Sediments are regarded to be a secondary source of contamination of filter-feeders with the toxins. As many other compounds, microcystin and nodularin are sorbed on sediment particles, especially those with fine-grained structure. Toxic cyanobacteria blooms pose a serious threat to humans and animals. A variety of methods and techniques, characterized by different sensitivity and selectivity, are used to assess the risk for people exposed to cyanobacterial bloom or dissolved toxin in water. Additionally, some national and international regulations were issued to protect users of drinking and recreational waters. The World Health Organization derived and recommended a provisional guideline value for drinking water of 1 µg dm-3. In the Directive of European Union (2006/7/EC) the importance of cyanobacterial risk in bathing sites has been addressed. With the view of the fact that cyanotoxins accumulate in edible aquatic organisms, this source of intoxication should not be overlooked

Environmental factors related to the distribution pattern of Raphidiopsis raciborskii and R. mediterranea in Central East Europe

Raphidiopsis raciborskii originates from tropical and subtropical regions, however its expansion toward temperate zone during last decades has been observed. Phenotypic plasticity, occurrence of ecotypes differing in their environmental adaptations and climate changes are indicated among factors responsible for its successful expansion. Much less is known about distribution pattern of Raphidiopsis mediterranea native for warm areas along Mediterranean cost. Therefore, the aim of the study was to determine the current distribution of these species in Polish and Lithuanian lakes and to detect environmental factors related to their occurrence. The R. raciborskii was much more common and occurred in 31 out of 112 lakes, while R. mediterranea in 7 lakes. The contribution of these species in total phytoplankton biomass ranged from 0.1 to 31% and from 0.1 to 2.6% respectively. Similarly to previous studies R. raciborskii was much more common in Western Poland where it significantly increased its contribution in phytoplankton biomass however it was detected in several new lakes in Eastern Poland. In Lithuania its occurrence is still limited to one lake. R. mediterranea occurred in similar number of lakes in both regions of Poland only. Among environmental factors conductivity and temperature were positively correlated with R. raciborskii biomass

Practical Guidelines for Nursing and Midwifery Diabetes care – 2020 A position of the Polish Federation for Education in Diabetology

Introduction. The history of recommendations by the Polish Federation for Education in Diabetology dates back to 2006, when guidelines for nurses/midwifes working with diabetic patients were first drawn up. However, the development of nurses and midwifes? competences requires stronger actions that foster a transition from experience-based towards evidence-based practice