Presence of human noro- and adenoviruses in river and treated wastewater, a longitudinal study and method comparison.

Norovirus (NoV) is one of the most common causative agents of waterborne gastroenteritis outbreaks. The main objective of the study was to determine the presence of human NoVs in river water and in treated wastewater (TW) released into the river. During a one-year survey in 2007/2008, NoVs were detected in 30.8% of river samples (20/65), and 40.5% of TW samples (17/45) with a real-time reverse transcription-PCR assay. NoVs were present in the river water in the winter and spring, coinciding with the NoV epidemiological peak in the community and the presence of NoVs in TW. Later in 2009, the concentration method used, pre-filtration with a Waterra filter combined with filtration through a negatively charged membrane, was evaluated against glass wool filtration and freeze-drying for the detection of adenoviruses in river water. The virus amounts measured varied greatly depending on the virus concentration method. The continued monitoring in the spring of 2009 also revealed that the average concentration of noro- and adenoviruses in TW was 2.64 × 10(3) and 1.29 × 10(4) pcr units per mL, respectively. No correlation between the presence of viruses and Escherichia coli was found. These results may be useful for risk assessment studies.

Suitability of passive sampling for the monitoring of pharmaceuticals in Finnish surface waters.

The occurrence of five pharmaceuticals, consisting of four anti-inflammatory and one antiepileptic drug, was studied by passive sampling and grab sampling in northern Lake Päijänne and River Vantaa. The passive sampling was performed by using Chemcatcher® sampler with a SDB-RPS Empore disk as a receiving phase. In Lake Päijänne, the sampling was conducted during summer 2013 at four locations near the discharge point of a wastewater treatment plant and in the years 2013 and 2015 at four locations along River Vantaa. The samples were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) in the multiple reaction monitoring mode. The concentrations of carbamazepine, diclofenac, ibuprofen, ketoprofen, and naproxen in Lake Päijänne determined by passive sampling ranged between 1.4-2.9 ng L(-1), 15-35 ng L(-1), 13-31 ng L(-1), 16-27 ng L(-1), and 3.3-32 ng L(-1), respectively. Similarly, the results in River Vantaa ranged between 1.2-40 ng L(-1), 15-65 ng L(-1), 13-33 ng L(-1), 16-31 ng L(-1), and 3.3-6.4 ng L(-1). The results suggest that the Chemcatcher passive samplers are suitable for detecting pharmaceuticals in lake and river waters.

Monitoring of Cryptosporidium and Giardia in the Vantaa river basin, southern Finland.

We compared two sampling methods to assess the contamination of the Vantaa river basin by Giardia cysts and Cryptosporidium oocysts: 10-1 grab samples, the common river mussel Anadonta piscinalis, were analysed for concentration of (oo)cysts from river water. The samples were collected 2-5 times in autumn 2001 from four wastewater treatment plants and four river water sites located downstream of the plants, and six times from raw water of a drinking water plant using the river as water source. The presence of Giardia and Cryptosporidium was analysed by IF microscopy and PCR. Both cysts and oocysts were detected at all sampling sites, but oocysts were more common than cysts in river water samples. In contrast, cysts were more common in A. piscinalis. Most Cryptosporidium-positive samples were of genotype 2 and Giardia were assemblage B. In river water, MPN of Escherichia coli did not correlate to the presence of (oo)cysts. In conclusion, low (oo)cyst counts were regularly identified in the Vantaa river basin which is contaminated by discharges of treated wastewater of human origin. In general, both methods to appropriate to detect (oo)cysts, but grab samples yielded more positive results. Grab sampling is also more practical and less expensive than analysis of A. piscinalis.

Endotoxins associated with cyanobacteria and their removal during drinking water treatment.

The aim of this study was to investigate endotoxin concentrations in cyanobacterial water blooms and strains, and to assess the removal of endotoxins during drinking water treatment. Endotoxin concentrations were measured from 151 hepatotoxic, neurotoxic and non-toxic cyanobacterial water blooms by using Limulus amebocyte lysate (LAL) assay, and the results were compared to bacterial data. Endotoxin activities ranged from 20 to 3.8 x 10(4) endotoxin units (EU) per ml. Endotoxicity of the samples correlated with phycobiliprotein concentration that was used to assess cyanobacterial abundance, heterotrophic plate count, and Aeromonas spp. but it did not correlate with the number of coliforms or streptococci. The high endotoxin concentrations occasionally detected in the water bloom samples were probably due to Gram negative bacteria that existed together with cyanobacteria since the 26 axenic cyanobacterial strains from different genera that were studied showed very low endotoxin activity. No differences in endotoxin activity were detected between hepatotoxic, neurotoxic and non-toxic strains. Removal of endotoxins during drinking water treatment was studied at nine waterworks that previously had been associated with high numbers of cyanobacteria and that used different processes for water purification. Endotoxin concentration in raw waters ranged from 18 to 356 EU ml(-1). The treatment processes reduced 59-97% of the endotoxin activity; in the treated water the concentration ranged from 3 to 15 EU ml(-1). The most significant reduction occurred at the early stages of water treatment, during coagulation, settling and sand filtration. Activated carbon filtration either increased or had no effect on endotoxin concentration. Ozonation and chlorination had little effect on the endotoxin concentrations.

First observation of cylindrospermopsin in Anabaena lapponica isolated from the boreal environment (Finland).

The cyanobacterial cytotoxin cylindrospermopsin has been mostly associated with cyanobacteria present in tropical and subtropical regions. Cylindrospermopsin has recently been found in cyanobacterial samples in central and southern Europe but the possible presence of the toxin in northern Europe has been unknown. Fifty-eight field and laboratory culture samples of Finnish cyanobacteria were analyzed by high-performance liquid chromatography combined with UV diode-array detection, multiple reactant monitoring in a triple-quadrupole mass spectrometer (MS), and accurate mass measurements using a time-of-flight MS instrument. Cylindrospermopsin was confirmed by all three techniques in a culture sample of Anabaena lapponica at a concentration of 242 microg cylindrospermopsin per g freeze-dried cyanobacterial material.

Paucibacter toxinivorans gen. nov., sp. nov., a bacterium that degrades cyclic cyanobacterial hepatotoxins microcystins and nodularin.

Thirteen bacterial isolates from lake sediment, capable of degrading cyanobacterial hepatotoxins microcystins and nodularin, were characterized by phenotypic, genetic and genomic approaches. Cells of these isolates were Gram-negative, motile by means of a single polar flagellum, oxidase-positive, weakly catalase-positive and rod-shaped. According to phenotypic characteristics (carbon utilization, fatty acid and enzyme activity profiles), the G+C content of the genomic DNA (66.1-68.0 mol%) and 16S rRNA gene sequence analysis (98.9-100% similarity) the strains formed a single microdiverse genospecies that was most closely related to Roseateles depolymerans (95.7-96.3% 16S rRNA gene sequence similarity). The isolates assimilated only a few carbon sources. Of the 96 carbon sources tested, Tween 40 was the only one used by all strains. The strains were able to mineralize phosphorus from organic compounds, and they had strong leucine arylamidase and chymotrypsin activities. The cellular fatty acids identified from all strains were C(16:0) (9.8-19%) and C(17:1)omega7c (<1-5.8%). The other predominant fatty acids comprised three groups: summed feature 3 (<1-2.2%), which included C(14:0) 3-OH and C(16:1) iso I, summed feature 4 (54-62%), which included C(16:1)omega7c and C(15:0) iso OH, and summed feature 7 (8.5-28%), which included omega7c, omega9c and omega12t forms of C(18:1). A more detailed analysis of two strains indicated that C(16:1)omega7c was the main fatty acid. The phylogenetic and phenotypic features separating our strains from recognized bacteria support the creation of a novel genus and species, for which the name Paucibacter toxinivorans gen. nov., sp. nov. is proposed. The type strain is 2C20(T) (=DSM 16998(T)=HAMBI 2767(T)=VYH 193597(T)).

First report of saxitoxin in Finnish lakes and possible associated effects on human health.

This study is the first report of saxitoxin in cyanobacterial blooms in Finland. Bloom samples (n = 50) were collected from Finnish freshwater sites during summer months of 2002 and 2003. These samples were screened for the presence of paralytic shellfish toxins (PSTs) using the Jellett rapid PSP screening test. Samples testing positive for PSTs (n = 7) were further analyzed with saxiphilin- and voltage-gated sodium channel [(3)H]-STX-binding radioreceptor assays and liquid chromatography using fluorescence and mass spectrometric analysis. The results indicated that saxitoxin (STX) was the only PST analogue in the samples and that it was present in high concentrations, as much as 1 mg L(-1). Microscopic analysis revealed that 95%-100% of the phytoplankton in the positive samples consisted of Anabaena lemmermannii. The trophic status of lakes in which STX-containing blooms were found varied from oligotrophic to hypertrophic. All the lakes had high nitrogen-to-phosphorus ratios. In some instances, samples had been collected from sites where swimmers had reported adverse health effects, and in three such cases, reported adverse health effects were associated with sites from which samples testing positive for STX had been received. Symptoms of fever, eye irritation, abdominal pains, and skin rash were reported in children aged 2-10 years after exposure to the water. These were not the adverse human symptoms typical of STX poisoning; rather, they represented acute effects often reported following recreational exposure to cyanobacterial blooms.