PCDD/Fs and PCBs in Baltic herring during the 1990s

Baltic herring samples caught from the Baltic Sea during the spring periods of 1993-1994 and 1999 were analysed for polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), and polychlorinated biphenyls (PCB). For analyses, 1570 individual herring were combined to 120 pools. Correlations between concentrations of congeners 1,2,3,7,8-PeCDD, 1,2,3,7,8-PeCDF, 2,3,4,7,8-PeCDF, and 2,3,4,6,7,8-HxCDF, and age of herring were the strongest (r>0.8) followed by correlations between PCB congeners PCB 105, 118, 126, 156, 169 and 180 (r>0.7), and age of herring. Due to higher fat percentage in herring in the Gulf of Bothnia the concentrations of PCDD/Fs and PCBs on fresh weight (fw) basis were higher than in herring in the Gulf of Finland. The concentrations of WHO(PCDD/F)-TEQs ranged from 1 to 27 pg/g fw, depending on the age and catchment area of herring, and concentrations of WHO(PCB)-TEQs reached 32 pg/g fw. Between the two studied time points no clear downward trend in concentrations was observed.     

Ecophysiology of the benthic amphipod Monoporeia affinis in an open-sea area of the northern Baltic Sea: seasonal variations in oxygen consumption and ammonia excretion

Seasonal variations in the oxygen uptake rate ( ) and ammonia excretion rate ( ) of the benthic deposit-feeding amphipod Monoporeia affinis vere studied in an open-sea population of the northern Baltic Sea during three consecutive years (1991 to 1993). In the early summer an increase in the weightspecific by 22% (standard 1-mg individual) was registered; an even more striking change was noted in the , which showed an increase in the early summer of ca. six times the extremely low winter/spring valnes. The metabolic changes observed could not be attributed to temperature, which remained at steadystate throughout the year, nor could seasonal variations in the biochemical composition of the amphipods explain the results. Therefor, it is evident that quality-food abundance following the sedimentation of the spring phytoplankton bloom induces the observed early-summer elevations in and . In turn, the marked decrease in the towards autumn reflects the gradual depletion of quality-food in the benthic environment. Atomic O: N ratios indicated that at the sampling location, M. affinis uses lipid almost exclusively for metabolic energy throughout the year, except in early summer when the use of lipid and protein was observed to be almost equal. Results also indicated a time-lag between sedimentation of the phytoplankton bloom and metabolic response in the amphipod population.     

Static yields and quality issues: Is the agri-environment program the primary driver?

The Finnish agri-environmental program (AEP) has been in operation for 20 years with >90 % farmer commitment. This study aimed to establish whether reduced nitrogen (N) and phosphorus (P) use has impacted spring cereal yields and quality based on comprehensive follow-up studies and long-term experiments. We found that the gap between genetic yield potential and attained yield has increased after the AEP was imposed. However, many contemporary changes in agricultural practices, driven by changes in prices and farm subsidies, also including the AEP, were likely reasons, together with reduced N, but not phosphorus use. Such overall changes in crop management coincided with stagnation or decline in yields and adverse changes in quality, but yield-removed N increased and residual N decreased. Further studies are needed to assess whether all the changes are environmentally, economically, and socially sustainable, and acceptable, in the long run. The concept of sustainable intensification is worth considering as a means to develop northern European agricultural systems to combine environmental benefits with productivity.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0637-9) contains supplementary material, which is available to authorized users.     

Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) in Finnish semi-domesticated reindeer (Rangifer tarandus tarandus L.)

To explore the concentrations and dynamics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in Finnish semi-domesticated reindeer (Rangifer tarandus tarandus L.) the reindeer milk and tissue samples were collected from the sub-arctic northern Finland. Reindeer milk's PCB sum (1.20 ng g(-1) wet weight) and PCDD/F sum (0.70 pg g(-1) ww) in autumn were higher than in summer (PCBs 0.50 ng g(-1) ww and PCDD/Fs 0.20 pg g(-1) ww). The mean fat content in autumn milk (26%) was significantly higher than in summer (10%). Concentrations in reindeer milk were generally far below 50% of that in adult reindeer body burden. However, the bioaccumulation factors were multiple in milk/reindeer calf ratio and that aroused the question of other important exposure routes than lactation. The muscle and liver of reindeer calves had higher PCDD/F and PCB concentrations than adult animals that possibly indicate the significance of transfer of these compounds from dam to calf through lactation and placenta. However, PBDE concentrations were higher in adult reindeer, especially in liver. In addition, reindeer liver seems to have a special feature to collect highly toxic PCDD/Fs, although the PCB sum concentrations (range from 0.33 to 1.69 ng g(-1) wet weight) were clearly higher than the sums of PCDD/Fs (range from 3.78 to 39.2 pg g(-1) ww). Stillborn reindeer calves represented individuals who had got their PCDD/F, PCB and PBDE load only via the placenta. Concentrations in muscle and brown adipose tissue samples did not indicate dependency on fat content. Obviously effective placental transfer of PCBs and PBDEs from reindeer dam to foetus was seen in this study.     

Determining algal-available phosphorus in pulp and paper mill effluents: algal assays vs routine phosphorus analyses

We determined the potentially algal-available P (P(aa)) in pulp and paper mill effluents by two bioassay techniques (a dual-culture assay and a batch approach) and compared it with chemically analysed P (total P, total dissolved P, reactive P, dissolved reactive P and dissolved hydrolysable P). The mean P(aa) given by the dual-culture assay was within a 40% range of that given by the batch approach. The P(aa) obtained by both bioassays differed from total P. Dissolved reactive P appeared to be the most readily available chemical P fraction, but other P fractions also contributed to P(aa). The analysis of reactive P, which involves direct staining of an unfiltered sample, best approximated the P(aa) given by the dual-culture assay (relative error 9%). The results suggest that assessment of eutrophying effluent P can be improved by analysing simple chemical P fractions in wastewater. The fractions to be analysed, however, may be site specific.     

Extractability of trace elements in precipitated calcium carbonate (PCC) waste from an integrated pulp and paper mill complex

From the utilization point of view, it is notable that the total element concentrations in the precipitated calcium carbonate (PCC) waste were significantly lower than the maximal allowable heavy metal concentrations for fertilizers used in agriculture and in forestry, set on the basis of the EU and Finnish legislation. The easily soluble Ca concentration of 168.5g kg(-1) (d.w.) in PCC waste was 105 times higher than the typical value of 1.6g kg(-1) (d.w.) in the coarse mineral soil in Finland indicates that the PCC waste is a potential agent for soil remediation and for improving soil fertility if it is used as fertilizer. According to a five-stage sequential extraction procedure, the highest concentrations of most of the elements occurred either in HF+HNO3+HCl or H2O2+CH3COONH4 fraction. This means that the major part of the elements retained in the PCC waste are not easy to extract (leach) under conditions normally found in nature. This is beneficial since, if inorganic materials and by-products are utilized in earth construction, the content of harmful compounds must be low and the harmful components must be tightly bound to the matrix.     

Contamination of River Kymijoki sediments with polychlorinated dibenzo-p-dioxins, dibenzofurans and mercury and their transport to the Gulf of Finland in the Baltic Sea

Kymijoki, the fourth largest river in Finland, has been heavily polluted by pulp mill effluents as well as the chemical industry. Up to 24,000 ton of wood preservative, chlorophenol known as Ky-5, was manufactured in the upper reaches of the river, an unknown amount of which was discharged into the river between 1940 and 1984. Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) occurred as impurities in the final Ky-5 product. The PCDD/F concentrations and burden in the river sediments were studied and the transport of PCDD/Fs from contaminated sites downstream and into the Gulf of Finland in the Baltic Sea was estimated. More than 190 sediment cores were sampled to estimate the volume of contaminated sediments and the total PCDD/F burden. The transport of PCDD/Fs was estimated using sediment traps placed at several sites. The survey revealed that sediments in the river were heavily polluted by PCDD/Fs, the main toxic congener being 1,2,3,4,6,7,8-heptachlorodibenzofuran, a major contaminant in the Ky-5 product. The mean total concentration at the most polluted river site downstream from the main source was 42000 microg kg(-1) d.w. (106 microg I-TEQ kg(-1)). The elevated concentrations in the coastal region and the present estimated transport from the River Kymijoki confirm earlier assessments that the river is a major source of PCDD/F for the Gulf of Finland.