Bioaccumulation of POPs from contaminated sediment to lamprey<Emphasis Type="Italic">(lampetra fluviatilis l.</Emphasis>) larva

Background  Adult sea lampreys, a delicate food species catch from Baltic Sea rivers, migrate from sea and spawn to sediments of still river water areas. Their larva live there four years before return to sea. The few published studies of toxicity of the sediment contaminants to the lamprey larva, however, do not include chlorinated persistent organic pollutants (POPs), thus far. Kymijoki River in southeast Finland is known for high polychlorinated POP contamination which has been measured to accumulate in several bottom fauna and fish species. Goal of the Study  To obtain the first screening results of the bioaccumulation power of POPs from sediment to lamprey larva during their life stage in the contaminated sediment. The accumulated dioxin-type of toxic load (TEQ) was also studied as a possible human hazard. Methods  Surface sediment and lamprey larva were sampled from four localities of the lower Kymijoki River and analysed for MeO-PBDEs, PBDEs, PCBs, PCDDs, PCDEs, PCDFs, and PCDTs by solvent extraction, column clean up and GC/MS procedures. The larva were sorted to seven composites according to locality and (for one place) size of the specimens (to classes of small, medium and large individuals). From the analysis results, TEQ values for composites and the bioaccumulation factors from dry sediment to fresh larva (BSAF), from dry sediment to larva lipid (BSAFlw) and from sediment organic carbon to larva lipid (BSAFoc) were calculated. Results and Discussion  TEQ load was highest (about 500 pg g^-1 ww) in large larva composite due to high bioaccumulation of PCB 118, 1,2,3,4,7,8-hexachlorodibenzo-p-dioxin (D66) and toxic penta- to octa-CDFs. A high positive significant correlation was found between weight and length of larva. Instead, lipid content had no significant correlations with weight and length of larva. Larva lipid or sediment organic carbon did not correlate significantly with any of the calculated BSAF, BSAFlw and BSAFoc values. Therefore, statistical comparisons between substance properties and bioaccumulation rate were possible for BSAF alone. These comparisons indicated a slightly significant increase of PCBs, but very significant decrease of PCDF bioaccumulation from sediment to larva by increase of the number of chlorine atoms (NCI) in the molecule. This property of highly chlorinated PCDFs indicates, as found earlier for local fish, a kinetic control of bioaccumulation by slow release from sediment back to water and the food chain. Recommendation and Outlook  The results obtained point out that bioaccumulation of POPs in lamprey larva is a possible source of toxic hazard to human food consumption and to development of lamprey species. Therefore, both larva and adult lampreys should be studied further for significance of their POP contamination compared with other experiences on impact of POPs to human and wildlife.     

An Electronic Nose and Indicator Volatiles for Monitoring of the Composting Process

The aim of this research was to study whether electronic nose sensor technology (NST 3320, Applied Sensor, Sweden) can be used effectively for monitoring of the composting process. The effect of aeration on the composting process was examined using two aeration levels representing insufficient and optimal aeration for composting. An additional aim was to identify possible indicator gases in the volatile organic compound profiles of the composts by on-line FT-IR and gas chromatographic determinations. The results indicated that the electronic nose was able to distinguish between the two composter bins after 13 days of composting. Of the volatile metabolites that were identified, methyl ethyl ketone (MEK) proved to be a suitable indicator compound of anaerobicity as it was only produced in considerable quantities in the insufficiently aerated composter bin.     

Consumption of juice fortified with oregano extract markedly increases excretion of phenolic acids but lacks short- and long-term effects on lipid peroxidation in healthy nonsmoking men

Oregano has been shown to possess antioxidant capacity in various in vitro models and has thus been suggested to be potentially beneficial to human health, but studies in humans are lacking. The aim of this study was to investigate the bioavailability and the effects of Origanum vulgare extract supplementation on serum lipids and lipid peroxidation in healthy nonsmoking men. A four-week double-blinded supplementation trial was concluded in which volunteers (n = 45) were randomized to consume daily mango-orange juice (placebo), mango-orange juice enriched with 300 mg/d total phenolic compounds from oregano extract, or mango-orange juice enriched with 600 mg/d total phenolic compounds from oregano extract. The excretion of phenolic compounds was markedly increased in the higher phenolic group as compared to the placebo group, but no significant changes were observed in the safety parameters, serum lipids, or biomarkers of lipid peroxidation.     

Rapid immunoassay for detection of Cryptosporidium oocysts

A direct immunological method by means of latex agglutination (LX) reaction was applied to the demonstration of Cryptosporidium oocysts from stools and gut homogenates. The LX method gave a positive diagnosis for all the specimens judged positive by the modified Ziehl-Neelsen technique, which served as a reference method, The results of the study indicate that the LX method can be adopted as a diagnostic tool for cryptosporidiosis, but further study concerning the specificity and sensitivity of the method is clearly warranted.     

Occurrence of Antibodies to Group Specific Chlamydia Antigen in Cattle and Reindeer Sera in Finnish Lapland

The occurrence of group specific complement fixing antibodies was studied in random sera of cattle and reindeer in Finnish Lapland. Sixty-eight (40.5%) of the 168 cattle sera were positive. Sixty 4hree (21.6 %) of the 291 reindeer sera were positive. The difference is statistically nearly significant in the t-test. The antibody titer ≥ 1:16 was regarded as positive. The antibody frequency of cattle sera was statistically significantly higher and the antibody frequency of reindeer sera was nearly significantly higher than in earlier studies on cattle sera in South and Central Finland. The reasons are discussed.     

Temperature sum accumulation effects on within-population variation and long-term trends in date of bud burst of European white birch (Betula pendula)

Within-population variation in phenology of boreal trees indicates their adaptability to climatic variations. Although interannual variations in date of bud burst have been widely discussed, little is known about within-population variation, the key determinants for this variation and the effects of this variation on estimates of trends in bud burst date. Over a period of nine years, we monitored timing of bud burst daily in 30 mature white birch (Betula pendula Roth) trees in a naturally regenerated stand. Our results revealed not only large interannual variation but also considerable intraannual variation among individual trees in date of bud burst, the maximum within-population variation being four weeks. Bud burst can be accurately predicted by the date when a threshold value of temperature sum in spring is reached (base temperature +5 degrees C). Based on this temperature sum and past temperature records, we estimated the trend in date of bud burst. The linear trend estimate based on the years 1926-2005 is an advancement of 1.2 days per decade (95% confidence interval, +/- 0.7 days), which is much less than that predicted by time series based on coarser time intervals. We conclude that, because of large interannual differences, and large annual within-population variations in bud burst, estimates of bud burst date based on measurements made over a period of only a few decades are unreliable.     

Impacts of forest drainage improvement on stream biota: A multisite BACI-experiment

Impacts of forestry have been described in many studies, with a strong focus on changes in run-off water quality. Biological responses to forest drainage and the efficiency of commonly used water protection methods remain largely unknown, however. We used a six-year replicated before-after-control-impact (BACI) field experiment to assess the effects of forest drainage improvement works (ditch cleaning; digging of supplementary ditches) on water chemistry, sedimentation, brown trout egg mortality and macroinvertebrate community composition in six headwater streams in Northern Finland. Standard water protection methods (ditch break combined with sedimentation pit) were used to reduce fine sediment (<1.0 mm) loading into the streams. Six artificial spawning sites were constructed in each stream, three downstream (treatments) and three upstream (controls) of the drainage areas. Sediment loading did not increase after forest drainage, and no changes were detected in water quality. Brown trout egg mortality rate increased after drainage works, but more so in the upstream controls than downstream treatment sections, and only in smaller (watershed <6.25 km²) streams. All macroinvertebrate metrics (e.g. total macroinvertebrate diversity and density) decreased significantly through time. However, these responses were observed in both control and treatment sections, and could not have been caused by the drainage works directly but were rather related to inter-annual variability in precipitation and discharges. Our results thus highlight the importance of placing results from local monitoring studies in a regional context.     

Comparison of Variable-Number Tandem-Repeat Markers typing and IS1245 Restriction Fragment Length Polymorphism fingerprinting of Mycobacterium avium subsp. hominissuis from human and porcine origins

Background

Animal mycobacterioses are regarded as a potential zoonotic risk and cause economical losses world wide. M. avium subsp. hominissuis is a slow-growing subspecies found in mycobacterial infected humans and pigs and therefore rapid and discriminatory typing methods are needed for epidemiological studies. The genetic similarity of M. avium subsp. hominissuis from human and porcine origins using two different typing methods have not been studied earlier. The objective of this study was to compare the IS1245 RFLP pattern and MIRU-VNTR typing to study the genetic relatedness of M. avium strains isolated from slaughter pigs and humans in Finland with regard to public health aspects.

Methods

A novel PCR-based genotyping method, variable number tandem repeat (VNTR) typing of eight mycobacterial interspersed repetitive units (MIRUs), was evaluated for its ability to characterize Finnish Mycobacterium avium subsp. hominissuis strains isolated from pigs (n = 16) and humans (n = 13) and the results were compared with those obtained by the conventional IS1245 RFLP method.

Results

The MIRU-VNTR results showed a discriminatory index (DI) of 0,92 and the IS1245 RFLP resulted in DI 0,98. The combined DI for both methods was 0,98. The MIRU-VNTR test has the advantages of being simple, reproducible, non-subjective, which makes it suitable for large-scale screening of M. avium strains.

Conclusions

Both typing methods demonstrated a high degree of similarity between the strains of human and porcine origin. The parallel application of the methods adds epidemiological value to the comparison of the strains and their origins. The present approach and results support the hypothesis that there is a common source of M. avium subsp. hominissuis infection for pigs and humans or alternatively one species may be the infective source to the other.