Using Fish as a Sentinel in Risk Management of Contaminated Sediments.

Sediments polluted by historical emissions from anthropogenic point sources are common in industrialized parts of the world and pose a potential threat to the function of aquatic ecosystems. Gradient studies using fish as a bioindicator are an option to assess the ecological impact of locally polluted areas. This study investigates the remaining effects of historical emissions on sediments outside ten Swedish pulp and paper mills using perch (Perca fluviatilis). The aim has been to obtain a general picture of the impact area of local deposits of cellulose fiber-rich sediments containing elevated levels of trace metals, e.g., Hg, and organochlorines, e.g., dioxins. In addition to analyzing contaminant levels in muscle and liver tissue, morphological measures in the fish that constitute biomarkers for health and reproductivity were measured. Another aim was to augment existing historical data sets to observe possible signs of environmental recovery. Overall, the results indicate only a minor elevation in contaminant levels and a minor impact on the fish health status in the polluted areas, which in several cases is an improvement from historical conditions. However, exceptions exist. Differences in the ecosystems' responses to pollution loads are primarily explained by abiotic factors such as water turnover rate, bottom dynamic conditions, and water chemistry. Weaknesses in the sampling methodology and processing of data were identified. After minor modifications, the applied survey strategy has the potential to be a management tool for decision-makers working on the remediation of contaminated areas.

Using a dynamic mass balance model to predict fate and transport of PCBs in a polluted boreal lake in Sweden.

In 2013, a screening survey including fish (European perch, Perca fluviatilis) from 20 locations in the Stockholm region of Sweden indicated exceptionally high levels of PCBs (>450 ng ΣPCB7/g ww) in Lake Oxundasjön. An extensive sampling program was launched to define the magnitude and area of impact of PCBs. Moreover, a dynamic mass balance model approach was applied to identify and quantify key transport processes and predict the long-term turnover of PCBs given various remediation scenarios. Based on the dating of sediment profiles, primary emissions of PCBs to Lake Oxundasjön have likely occurred from the end of the 1940s until 1980, reaching the lake via one of its tributaries. Presently, the main source of PCBs is diffusion from the lake sediments. From the lake outlet, >400 g ΣPCB7/yr are transported to Lake Mälaren (the third largest lake in Sweden), supplying drinking water for parts of the Stockholm area. Remediation actions are necessary to reduce the PCB levels in fish below today's marketing limits and environmental quality standards. With natural recovery, our results indicate that the PCB levels in non-migratory fish from Lake Oxundasjön will be elevated for decades to come. The mass of PCBs stored in the lake sediments was estimated, and to our knowledge, Lake Oxundasjön is the most heavily PCB contaminated lake in Sweden. The system constitutes a unique opportunity to test and develop a mathematical mass balance model for PCBs, with substantial data acquired from different aquatic matrices. The model presented in the paper is applicable for risk assessments of PCBs, and the results contribute to the general understanding of the transport and turnover dynamics of PCBs in aquatic ecosystems.

Efficiency of an emissions payment system for nitrogen in sewage treatment plants - a case study.

An emissions payment system for nitrogen in Swedish sewage treatment plants (STPs) was evaluated using a semi-empirical approach. The system was based on a tariff levied on each unit of nitrogen emitted by STPs, and profitable measures to reduce nitrogen emissions were identified for twenty municipal STPs. This was done through direct involvement with the plant personnel and the results were scaled up to cover all treatment plants larger than 2000 person equivalents in the Swedish tributary areas of the Kattegat and the Baltic Proper. The sum of costs and nitrogen reductions were compared with an assumed command-and-control regulation requiring all STPs to obtain 80% total nitrogen reduction in their effluents. Costs for the latter case were estimated using a database containing standard estimates for reduction costs by six specified measures. For both cases a total reduction target of 3000 tonnes of nitrogen was set. We did not find that the emissions payment system was more efficient in terms of total reduction costs, although some practical and administrative advantages could be identified. Our results emphasize the need to evaluate the performance of policy instruments on a case-by-case basis since the theoretical efficiency is not always reflected in practice.

Multiple stressors threatening the future of the Baltic Sea-Kattegat marine ecosystem: implications for policy and management actions.

The paper discusses the combined effects of ocean acidification, eutrophication and climate change on the Baltic Sea and the implications for current management strategies. The scientific basis is built on results gathered in the BONUS+ projects Baltic-C and ECOSUPPORT. Model results indicate that the Baltic Sea is likely to be warmer, more hypoxic and more acidic in the future. At present management strategies are not taking into account temporal trends and potential ecosystem change due to warming and/or acidification, and therefore fulfilling the obligations specified within the Marine Strategy Framework Directive, OSPAR and HELCOM conventions and national environmental objectives may become significantly more difficult. The paper aims to provide a basis for a discussion on the effectiveness of current policy instruments and possible strategies for setting practical environmental objectives in a changing climate and with multiple stressors.

Structure-related distribution of PCDD/Fs, PCBs and HCB in a river-sea system.

Water concentrations of PCDD/Fs, HCB, and non-ortho, mono-ortho, and non-dioxin-like PCBs were measured four times during 1 year in a coastal area of the Baltic Sea, to investigate background levels and distribution behaviour. Sampling sites included two rivers, an estuary, and the sea. Particulate and apparently dissolved concentrations were determined using active sampling (filters+PUFs), while freely dissolved concentrations were determined using passive sampling (POM-samplers). The distribution between particulate+colloidal and freely dissolved phases, in the form of TOC-normalized distribution ratios (K(TOC)), was found to be near or at equilibrium. The observed K(TOC) were not significantly different between sampling sites or seasons. For PCDD/Fs, the concentrations were significantly correlated to suspended particulate matter (SPM), while no correlation to organic carbon (TOC) was observed. In the estuary and the sea, PCB concentrations were correlated to TOC. The sorption of various congeners to SPM and TOC appeared to be related to both hydrophobicity and 3D-structure. The PCDD/F concentration in the sea decreased to one third in May, likely connected to the increased vertical flux of particles during the spring bloom.

Indications of recovery from hypoxia in the inner Stockholm archipelago.

Improved benthic conditions compared to the 1990s were found during benthic investigations, including sediment and benthic macrofauna in the inner Stockholm archipelago during 2008. In the 1990s, these areas were dominated by black and laminated surface sediments and very sparse fauna. A clear relationship was found when comparing sediment status with the benthic macrofauna. Reduced surface sediment and impoverished macroinvertebrate community was only found at one sampling station representing an enclosed part of the inner archipelago, whereas the other seven stations, with depths ranging from 20 to 50 m, had oxidized surface sediments and considerable biomasses of benthic macrofauna (6-65 g m(-2)) dominated by the invading polychaete Marenzelleria neglecta. An extrapolation of the results shows that, within the investigated area, the coverage of reduced surface sediments had decreased from approximately 17% in the late 1990s to 4% in 2008.

Estimating costs and potentials of different methods to reduce the Swedish phosphorus load from agriculture to surface water.

This paper reviews 17 measures to reduce phosphorus leakage from Swedish agriculture to surface waters. Our aim is to evaluate the possible contribution from agriculture to achieve environmental goals including the Baltic Sea Action Plan. Using a regional approach integrating the variability in field specific characteristics, typical costs and national potential for the included measures may be estimated without identifying, e.g., suitable individual fields for implementation. The result may be helpful to select suitable measures but may also influence the design of environmental targets before they are determined. We find that the cheapest measures are reduced phosphorus content in animal food and fertilizer application supervision in pig farms, both measures with annual potentials of around 50t each, and costs of euro7 to euro11 kg(-1)yr(-1). The total potential of the listed measures is an annual phosphorus reduction to surface waters of 242t. If the most expensive measures are excluded (>euro1000 kg(-1)yr(-1)) and including retention in lakes the phosphorus transport to the sea could be reduced by 165 t yr(-1). This amount can be compared with the Swedish commitment in the Baltic Sea Action Plan (BSAP) to reduce input to the Baltic Proper by 290 t yr(-1).

The optimal size of dynamic phosphorus models for coastal areas.

One method to assess environmental effects from industrial emissions to coastal and inland waters, e.g. from pulp and paper industries, is to quantify these emissions with mass balance models. In this study six different mass balance models for phosphorus with varying degrees of complexity have been tested in 11 Swedish coastal areas. The majority of these areas are recipients of pulp and paper industries. The accuracy of model predictions of phosphorus and chlorophyll is evaluated and compared between models. The results imply that for the included water bodies, models containing state variables for phosphorus in surface water and deep water are superior to models treating the water column as a completely mixed entity. The results do not justify the separation of phosphorus into dissolved and particulate fractions, but for chlorophyll predictions the results were significantly improved when phytoplankton was included as a state variable. Unless detailed descriptions or predictions of chlorophyll dynamics are required, modelling eutrophication in coastal areas may be considered as a matter of total phosphorus in two water compartments plus sediments.

Parathyroid surgery in Scandinavia.

A review of the organization and practice of parathyroid surgery in Scandinavia indicated that it was undertaken in about half of the surgical clinics. About half of these clinics treated only primary hyperparathyroidism (HPT), and in the great majority all parathyroid operations were done by one or two surgeons. The results of surgical treatment were compared in two large Scandinavian series of primary HPT, one based on a general survey of parathyroid surgery in 1975, and the other on results obtained during 1971-1980 in centres specializing in endocrine surgery (Bergen, Stockholm, Uppsala). In the latter series 90% of the patients were normocalcaemic at follow-up averaging 4.4 years after parathyroid surgery whereas in the general survey the rate of normocalcaemia was 76%. At hospitals performing less than ten parathyroid operations per year it was only 70% and there was high incidence of persistent HPT (15%) and presumed permanent hypoparathyroidism (14%). The findings strongly advocate special training and interest in parathyroid surgery in order to ensure success.

Adrenal gland surgery. Preoperative location of lesions, histologic findings and outcome of surgery.

The accuracy of various techniques for preoperative location of adrenal lesions was studied in 55 consecutive cases, and the perioperative course and outcome of surgery were analyzed. CT correctly located 94% of all adrenal tumours, was less accurate (42%) in hyperplasia and gave no false-positive results. Selective angiography revealed 75% of the tumours, but was likewise diagnostically inadequate in adrenal hyperplasia. Adrenal venous sampling correctly located 80% of tumours and of hyperplasia. In hyperplasia it was the single most successful procedure for detecting the site of adrenal hyperfunction. Phlebography gave misleading information in almost 45% of cases. The perioperative complications included splenic rupture necessitating splenectomy (3 cases), superficial wound infection (2), pneumonia (4) and subphrenic abscess (1). There were no perioperative deaths. The study indicated CT to be the principal procedure for preoperative location of adrenal disorders. In some cases with adrenal hyperfunction, venous sampling should be added. Adrenal surgery can be performed with low morbidity and no mortality and with favourable long-term outlook in cases of benign lesion.

Early postoperative course following elective splenectomy in haematological diseases: a high complication rate in patients with myeloproliferative disorders.

One hundred and sixty-seven patients subjected to splenectomy on haematological indications were studied. They were grouped into five diagnostic categories: auto-immune disorders (52 patients), Hodgkin's disease (32) lymphoproliferative malignancies (60), myeloproliferative malignancies (18) and miscellaneous (5). The total number of complications and deaths were 42 (25 per cent) and nine (5 per cent), respectively. Infections were the most common complication, occurring in 30 cases and accounting for 59 per cent of all sequelae. Patients with auto-immune disorders had a high frequency of subphrenic left-sided abscesses (5/52). Splenectomy for Hodgkin's disease was associated with a very low frequency of complications. In the 60 patients with lymphoproliferative malignancies left-sided pneumonia was common (9/60). Complications occurred in 56 per cent of the patients with myeloproliferative disorders, the associated mortality rate being 28 per cent. It is concluded that elective splenectomy in haematological diseases seems to be a safe procedure in most patients with the exception of individuals with myeloproliferative malignancies. The high operative risk in this group makes the benefit questionable. In patients with auto-immune disorders the high frequency of subphrenic abscesses indicates that prophylactic antibiotic treatment should be considered.

Fine needle biopsy and scintigram in the preoperative diagnosis of thyroid lesions.

Fine needle biopsies (FNB) of the thyroid were examined from 860 patients. In 703 cases follicular cells without atypia were found and in this group of patients the clinical diagnosis was nodular goitre. Operations were performed in 138 patients and in 97 cases the cytological finding could be correlated to the histopathological diagnosis. In 33 of these patients thyroid carcinoma was histologically verified. In 26 of the carcinoma cases cytologic examination showed grave atypia or changes indicating carcinoma. The cases in which the cytological diagnoses were falsely negative are discussed. Moderate cellular atypia occurred in one case with papillary carcinoma. In two cases the cytological examination gave a false positive diagnosis of cancer, both representing thyroiditis of the lymphoid type. The scintigrams in patients with thyroid carcinoma are also presented. Cold nodules were found in 10/19 patients and a hot nodule in .1 patient. In 3 patients the scintigrams were normal and in another 5 inconclusive. The results indicate that thyroid scintigrams can only be used as a supplement to the physical examination and a guidance for FNB. The contribution of FNB in the decision to operate is discussed and it is concluded that FNB is a valuable adjunct in preoperative diagnosis of thyroid lesions. The best diagnostic results are obtained when there is a close cooperation between clinician, radiologist, cytologist and pathologist.

Relationships between calcium and phosphorus homeostasis, parathyroid hormone levels, bone aluminum, and bone histomorphometry in patients on maintenance hemodialysis.

Serum biochemistry related to calcium and phosphorus homeostasis and parathyroid function was studied together with bone histomorphometry after double-labeling with tetracycline and staining for aluminum in 17 patients without symptoms of bone disease, treated with maintenance hemodialysis for at least 6 months. A close correlation was found between the serum level of parathyroid hormone (PTH) and bone resorption surfaces and bone formation rates, both at tissue and basic multicellular unit (BMU) levels. The patients could be divided into a high turnover group with a normal mineralization process and a low turnover group with markedly defective mineralization. The second group was further characterized by lower PTH and higher fractional aluminum-stained trabecular bone surfaces. For the whole patient material, the fractional aluminum-stained surfaces related inversely to tetracycline-labeled surfaces and to bone formation rates at both BMU and tissue levels, but not to the time on dialysis or to the cumulative ingested amount of aluminum hydroxide. The data provide evidence that PTH or PTH-related factors, besides activating bone remodeling, directly enhance bone formation in dialysis patients and that aluminum incorporation into bone is associated with a progressive disturbance of bone mineralization.

Effects of 1,25- and 24,25-dihydroxycholecalciferol on parathyroid hormone release from human parathyroid cells in vitro.

The effects of 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) and 24,25-dihydroxycholecalciferol (24,25-(OH)2D3) on parathyroid hormone (PTH) release from human parathyroid cells were investigated using an in vitro system of dispersed cells. The cells were obtained from 7 patients with primary hyperparathyroidism (HPT) and adenoma, 4 patients with primary HPT due to hyperplasia and 2 patients with parathyroid hyperplasia secondary to chronic renal failure. The dispersed cells were incubated in tissue culture medium at low, normal and high external calcium concentrations for 2-16 h. There was a gradual suppression of PTH release (5-55%) when the calcium concentration in the medium was increased from 0.5 to 3.0 mM, thus indicating retained regulation of hormone release. The addition of 1,25-(OH)2D3 in concentrations of 0.1 and 1 ng/ml and of 24,25-(OH)2D3 in concentrations of 1.0 and 10 ng/ml during the incubations did not further affect the amount of PTH released by the cells. The concentrations of the different vitamin D metabolites tested closely correspond to levels observed under normal physiological conditions and during treatment with high doses of vitamin D in vivo. Thus, the findings contradict the idea of any direct short-term regulatory effect of either 1,25-(OH)2D3 or 24,25-(OH)2D3 on the secretion of PTH from hyperfunctioning human parathyroid tissue.

An investigation of biochemical and radiographic signs of hyperparathyroidism in chronic renal disease.

One hundred and twelve randomly selected patients with renal disease (22 on conservative treatment, 35 on haemodialysis and 55 with functioning kidney transplants) were subjected to a longitudinal and follow-up study of biochemical and radiographic signs of secondary hyperparathyroidism (HPT). Special interest was directed towards diagnostic criteria leading to the decision to perform parathyroid surgery, which had been undertaken in 18 patients. The five patients selected for parathyroidectomy while on conservative treatment were clearly distinguishable from the rest of the patients in this group, on the basis of hypercalcaemia, massive elevation of serum parathyroid hormone and radiographic abnormalities, findings which did not occur in patients in whom parathyroid surgery had not been considered. Six patients underwent parathyroidectomy while on haemodialysis. Preoperatively hypercalcaemia was observed in five and this was the only finding separating these patients from non-operated patients. Radiographic abnormalities were observed in only one operated patient. After kidney transplantation, long-standing hypercalcaemia was observed in 27% of patients. Seven patients underwent parathyroidectomy, hypercalcaemia being the indication for surgery in all cases. Hypercalcaemic patients could not be separated from normocalcaemic patients regarding any other determined biochemical variable, or regarding the incidence of osteonecrosis of weight-bearing joints, which was found in 18% of transplanted patients, and which was the only cause of major symptomatic bone disease observed in this study. The findings of hypercalcaemia as a major deciding factor for parathyroid surgery, a low incidence of radiographic bone disease, and absence of major symptomatic bone disease referable to HPT, are in keeping with a more liberal attitude to parathyroidectomy in chronic renal disease than has been stated in other recent reports. With a more expectant attitude and with more active medical treatment some of the operations performed on the patients in this study might have been avoided but, in general, the favourable outcome after surgery and the low overall incidence of clinical problems referable to bone disease at our unit would seem to support our active approach to parathyroid surgery.

Parathyroid pathology in hyperparathyroidism secondary to chronic renal failure.

Weights and histopathological changes in parathyroid glands were evaluated in relation to clinical and biochemical parameters in 42 patients who underwent parathyroidectomy for hyperparathyroidism (HPT) secondary to chronic renal failure. There was a positive relation (r = 0.71, p less than 0.01) between duration of renal insufficiency and total parathyroid glandular weight. The glandular weight was also closely related to the serum levels of parathyroid hormone (r = 0.67, p less than 0.01). No correlation was found between total parathyroid glandular weight or histopathological findings and clinical symptoms, serum levels of calcium, phosphate, alkaline phosphatases, calcium X phosphorus product or radiological evidence of bone disease. The enlargement of the glands was mostly uniform in the individual patient and all patients showed multiple gland involvement. This indicates that when parathyroid surgery is performed in patients with uraemia and secondary HPT, a radical approach, i.e. total parathyroidectomy with autotransplantation or subtotal parathyroidectomy, should always be used. In smaller glands only diffuse hyperplasia of parenchymal cells was generally found; fat cells were present in near-normal amounts. With increasing glandular weight, fat cells were more sparse and nodularity was common. In general, the proportion of oxyphil cells increased parallel with the total glandular weight, suggesting that this cell type is sensitive to stimulation. As a group, patients undergoing conservative renal treatment had suffered longer with renal disease, had larger parathyroid glands with more nodularity, and had more oxyphil cells than those undergoing parathyroidectomy while on haemodialysis.

Ultrasound scanning for preoperative location of parathyroid tumours.

Ultrasonic examination of the parathyroid glands has been used in 50 consecutive patients with surgically verified hyperparathyroidism. It revealed 21 of 32 parathyroid adenomas located in the neck. In 16 patients with primary or secondary (uraemic) hyperplasia, 11 out of 48 hyperplastic glands in the neck were identified by ultrasound. A parathyroid adenoma was revealed in all (3) patients with hypercalcaemic crisis. Enlarged parathyroid glands were correctly located in all (5) patients with adenomas and previous explorations of the neck, whereas two out of three glands were visualized by ultrasound prior to secondary explorations in 3 patients with hyperplasia associated with the multiple endocrine neoplasia syndrome type 1. Undetected parathyroid glands were generally smaller than those visualized by ultrasonic examination. It was often difficult to unequivocally establish that identified lesions represented parathyroid glands. Irregular noduli and cysts of the thyroid as well as lymph nodes could be misinterpreted as parathyroid lesions. A nodular thyroid goitre was present in almost half of the patients with a negative ultrasonic examination of the parathyroid glands.