Organochlorine contaminants in the muscle, liver and brain of seabirds (Larus) from the coastal area of the Southern Baltic.

The presence of persistent organic pollutants in the environment manifests itself most strongly in the marine trophic chain, where the highest link is comprised of seabirds. At the same time, seabirds are excellent indicators of contamination in their habitat. The present study concentrates on toxic substances: polychlorinated dibenzo-p-dioxin (PCDDs), polychlorinated dibenzofurans (PCDFs) and chlorinated organic pesticides (OCPs) accumulated in the livers, pectoral muscles and brains of dead gulls collected along the Polish coast of the Baltic Sea in the years 2010-12. The highest toxic equivalence was determined in the livers of Larus argentatus (TEQ(birds TEF)-28.3pgg(-1) ww) and Larus marinus (TEQ(birds TEF)-29.9pgg(-1) ww.). However, the toxic equivalence of muscles was lower and amounted to 3.9pgg(-1) ww. and 7.8pgg(-1) ww. respectively for the two species. The lowest toxic equivalence was found in the brains of birds, where only one, the most toxic, 2,3,7,8 TCDD congener was found (TEQ(birds TEF) 0.87pgg(-1) ww). The highest concentration of chloroorganic pesticides was determined in the brains of the birds (total OCP 167.8pgg(-1) ww.), lower concentrations were found in the livers (total OCP 92.1pgg(-1) ww.) and muscles (total OCP 43.1pgg(-1) ww.). With regard to pesticides, the highest proportion in the total OCP content was constituted by DDT and its isomers (liver 81%, muscles 77% and brain 55%). High concentrations of the studied pollutants in the livers of gulls found dead on the coast of the Southern Baltic could have been effected by levels of contamination in the birds' last meals, which resulted in a seven-fold increase of the liver's toxic equivalence and a two-fold increase in OCP concentration in relation to muscles.

The Ability of Airborne Microalgae and Cyanobacteria to Survive and Transfer the Carcinogenic Benzo(a)pyrene in Coastal Regions.

Air pollution has been a significant problem threatening human health for years. One commonly reported air pollutant is benzo(a)pyrene, a dangerous compound with carcinogenic properties. Values which exceed normative values for benzo(a)pyrene concentration in the air are often noted in many regions of the world. Studies on the worldwide spread of COVID-19 since 2020, as well as avian flu, measles, and SARS, have proven that viruses and bacteria are more dangerous to human health when they occur in polluted air. Regarding cyanobacteria and microalgae, little is known about their relationship with benzo(a)pyrene. The question is whether these microorganisms can pose a threat when present in poor quality air. We initially assessed whether cyanobacteria and microalgae isolated from the atmosphere are sensitive to changes in PAH concentrations and whether they can accumulate or degrade PAHs. The presence of B(a)P has significantly affected both the quantity of cyanobacteria and microalgae cells as well as their chlorophyll a (chl a) content and their ability to fluorescence. For many cyanobacteria and microalgae, an increase in cell numbers was observed after the addition of B(a)P. Therefore, even slight air pollution with benzo(a)pyrene is likely to facilitate the growth of airborne cyanobacteria and microalgae. The results provided an assessment of the organisms that are most susceptible to cellular stress following exposure to benzo(a)pyrene, as well as the potential consequences for the environment. Additionally, the results indicated that green algae have the greatest potential for degrading PAHs, making their use a promising bioremediation approach. Kirchneriella sp. demonstrated the highest average degradation of B(a)P, with the above-mentioned research indicating it can even degrade up to 80% of B(a)P. The other studied green algae exhibited a lower, yet still significant, B(a)P degradation rate exceeding 50% when compared to cyanobacteria and diatoms.

Airborne microalgal and cyanobacterial diversity and composition during rain events in the southern Baltic Sea region.

Airborne cyanobacteria and microalgae are commonly found in the atmosphere and may pose a serious human health risk. This study presents an innovative investigation of the washout efficiency of airborne cyanobacteria and microalgae in the Gulf of Gdansk (southern Baltic Sea). For the first time, the number and type of cyanobacteria and microalgae were determined in rainwater samples and in air before and after rainfall events. The number of cyanobacteria and microalgae cells in the rainwater samples ranged, depending on, e.g., weather conditions, from 100 cells L-1 to 342.2 × 103 cells L-1. Several harmful taxa, such as Chlorococcum sp., Oocystis sp., Anabaena sp., Leptolyngbya sp., Nodularia sp., Pseudanabaena sp., Synechococcus sp., Synechocystis sp., and Gymnodinium sp., were noted in our study. Washing out by rain is extremely relevant to human health and decreases the chance that people inhale these species and their toxic metabolic products. The greatest diversity of airborne microalgae and cyanobacteria was recorded in July 2019, despite this being the period with the lowest number of cells in rainwater samples. Research conducted in the southern Baltic Sea region confirmed the relationship between the occurrence of cyanobacteria and microalgae in the air and blooms in the sea. It is worth emphasizing that the number of microalgae and cyanobacteria cells decreased by up to 87% after a rainfall event relative to that before the rainfall event. The obtained results significantly increase the level of knowledge about cyanobacteria and microalgae present in the air. By demonstrating the washout efficiencies of cyanobacteria and microalgae, the results indicate the potential of individual taxa to be removed from the atmosphere with rainfall. The findings of this study are helpful for further research on airborne microorganisms and air quality.

Quantitative and qualitative variability of airborne cyanobacteria and microalgae and their toxins in the coastal zone of the Baltic Sea.

Apart from viruses and bacteria, cyanobacteria and microalgae present in the atmosphere may pose a threat to the health of humans by inducing illnesses and diseases. Yet, they play an important role in the environment, influencing the Earth's radiation budget by absorbing and scattering solar radiation. The present study determined the daily and seasonal qualitative and qualitative variabilities of airborne cyanobacteria and microalgae during both vegetative and non-vegetative seasons in the coastal zone of the Baltic Sea. Samples were collected from January to December 2020 with a Tisch six-stage microbiological impactor which was used as a substitute for the respiratory tract. The stage levels of the impactor represented the respiratory tract and reproduced lung penetration by airborne particles, which allowed us to assess penetration of cyanobacteria and microalgae to the deepest parts of the human respiratory system. A total of 296 samples of cyanobacteria and microalgae were collected during the day and 276 samples during the night. The results showed that cyanobacteria and microalgae were present in the air all year, and their maximum abundance was 1685 cells m-3 in July. Furthermore, the ability of these microorganisms to produce the toxin microcystin-LR (MC-LR) was confirmed, which has a high potential negative impact on human health. MC-LR has been found in Nostoc sp., Pseudanabaena sp., Leptolyngbya sp., Synechococcus sp., Gloeocapsa sp., Aphanothece sp., and Rivularia sp. maintained at our Culture Collection of Airborne Algae (CCAA), as well as from air samples. The highest concentrations of MC-LR were recorded in airborne Synechococcus sp. CCAA 46 and amounted to as much as 420 fg cell-1. In turn, the highest mean concentration of 0.95 µg L-1 for MC-LR was recorded in an air sample taken in May. This research expands the knowledge on cyanobacteria and microalgae present in the atmosphere in the coastal zone of the southern Baltic Sea. We propose these microorganisms be used as indicators for further research on bioaerosols, which are potentially dangerous to human health.

The current state of knowledge on taxonomy, modulating factors, ecological roles, and mode of action of phytoplankton allelochemicals.

Allelopathy is widespread in marine, brackish, and freshwater habitats. Literature data indicate that allelopathy could offer a competitive advantage for some phytoplankton species by reducing the growth of competitors. It is also believed that allelopathy may affect species succession. Thus, allelopathy may play a role in the development of blooms. Over the past few decades, the world's coastal waters have experienced increases in the numbers of cyanobacterial and microalgal blooming events. Understanding how allelopathy is implicated with other biological and environmental factors as a bloom-development mechanism is an important topic for future research. This review focuses on a taxonomic overview of allelopathic cyanobacteria and microalgae, the biological and environmental factors that affect allelochemical production, their role in ecological dynamics, and their physiological modes of action, as well as potential industrial applications of allelopathic compounds.

The first characterization of airborne cyanobacteria and microalgae in the Adriatic Sea region.

The presence of airborne cyanobacteria and microalgae as well as their negative impacts on human health have been documented by many researchers worldwide. However, studies on cyanobacteria and microalgae are few compared with those on bacteria and viruses. Research is especially lacking on the presence and taxonomic composition of cyanobacteria and microalgae near economically important water bodies with much tourism, such as the Adriatic Sea region. Here, we present the first characterization of the airborne cyanobacteria and microalgae in this area. Sampling conducted between 11th and 15th June 2017 revealed a total of 15 taxa of airborne cyanobacteria and microalgae. Inhalation of many of the detected taxa, including Synechocystis sp., Synechococcus sp., Bracteacoccus sp., Chlorella sp., Chlorococcum sp., Stichococcus sp., and Amphora sp., poses potential threats to human health. Aside from two green algae, all identified organisms were capable of producing harmful metabolites, including toxins. Moreover, we documented the presence of the cyanobacterium Snowella sp. and the green alga Tetrastrum sp., taxa that had not been previously documented in the atmosphere by other researchers. Our study shows that the Adriatic Sea region seems to be a productive location for future research on airborne cyanobacteria and microalgae in the context of their impacts on human health, especially during the peak of tourism activity.

Water soluble organic carbon in aerosols (PM1, PM2.5, PM10) and various precipitation forms (rain, snow, mixed) over the southern Baltic Sea station.

In the urbanized coastal zone of the Southern Baltic, complex measurements of water soluble organic carbon (WSOC) were conducted between 2012 and 2015, involving atmospheric precipitation in its various forms (rain, snow, mixed) and PM1, PM2.5 and PM10 aerosols. WSOC constituted about 60% of the organic carbon mass in aerosols of various sizes. The average concentration of WSOC was equal to 2.6µg∙m-3 in PM1, 3.6µg∙m-3 in PM2.5 and 4.4µg∙m-3 in PM10. The lowest concentration of WSOC was noted in summer as a result of effective removal of this compound with rainfall. The highest WSOC concentrations in PM2.5 and PM10 aerosols were measured in spring, which should be associated with developing vegetation on land and in the sea. On the other hand, the highest WSOC concentrations in PM1 occurred in winter at low air temperatures and greatest atmospheric stability, when there were increased carbon emissions from fuel combustion in the communal-utility sector and from transportation. WSOC concentrations in precipitation were determined by its form. Mixed precipitation turned out to be the richest in soluble organic carbon (5.1mg·dm-3), while snow contained the least WSOC (1.7mg·dm-3). Snow and rain cleaned carbon compounds from the atmosphere more effectively when precipitation lasted longer than 24h, while in the case of mixed precipitation WSOC was removed most effectively within the first 24h.

Effect of agriculture and vegetation on carbonaceous aerosol concentrations (PM2.5 and PM10) in Puszcza Borecka National Nature Reserve (Poland).

Elemental carbon (EC) and organic carbon (OC) concentrations were measured in PM2.5 and PM10 samples collected at Diabla Gora (Puszcza Borecka National Nature Reserve, Poland) between 1 January and 31 December 2009, to investigate the seasonal and daily concentration variations and source regions. Strict sampling and measurement procedure, together with analysis of air mass backward trajectories and pollutant markers, indicated that the most important sources of carbon in the aerosols over Diabla Gora were vegetation, agricultural activity, and biomass burning. The highest contribution of secondary organic carbon (SOC) in aerosol mass (70 %) was detected during summer as a result of increased vegetation. In spring and autumn, raised concentrations of primary OC, calcium, and potassium and the presence of ammonium nitrate were observed in aerosols due to emission from surrounding fields and forests, as well as from fires in Lithuania. Anthropogenic influence on the increase in concentration of all carbon species was observed only in winter, when air masses drifted in from habitations situated within a radius of 50 km from the Diabla Gora station. Transport was of sporadic significance to the measured concentrations, and only in PM2.5 when wind speed was close to 1 m s-1. In this case, the concentration of EC rose several fold. Such a tendency was particularly noticeable with the influx of air masses from nearby cities and the Polish-Russian border, which is located 29 km away from the station.