Sublethal Lead Exposure Alters Movement Behavior in Free-Ranging Golden Eagles.

Lead poisoning of animals due to ingestion of fragments from lead-based ammunition in carcasses and offal of shot wildlife is acknowledged globally and raises great concerns about potential behavioral effects leading to increased mortality risks. Lead levels in blood were correlated with progress of the moose hunting season. Based on analyses of tracking data, we found that even sublethal lead concentrations in blood (25 ppb, wet weight), can likely negatively affect movement behavior (flight height and movement rate) of free-ranging scavenging Golden Eagles (Aquila chrysaetos). Lead levels in liver of recovered post-mortem analyzed eagles suggested that sublethal exposure increases the risk of mortality in eagles. Such adverse effects on animals are probably common worldwide and across species, where game hunting with lead-based ammunition is widespread. Our study highlights lead exposure as a considerably more serious threat to wildlife conservation than previously realized and suggests implementation of bans of lead ammunition for hunting.

An evaluation of free water surface wetlands as tertiary sewage water treatment of micro-pollutants.

Increased attention is currently directed towards potential negative effects of pharmaceuticals and other micro-pollutants discharged into the aquatic environment via municipal sewage water. A number of additional treatment technologies, such as ozonation, have therefore been suggested as promising tools for improving the removal efficiency of pharmaceuticals in existing Sewage Treatment Plants (STPs). Constructed wetlands are also capable of removing a variety of micro-pollutants, including some pharmaceuticals, and could hence be a resource efficient complement to more advanced treatment technologies. The purpose of the present study was therefore to increase the knowledge base concerning the potential use of constructed wetlands as a treatment step to reduce emissions of organic micro-pollutants from municipal sewage effluents. Under cold winter conditions, incoming and outgoing waters from four Swedish free water surface wetlands, operated as final treatment steps of sewage effluent from municipal STPs, were sampled and analyzed for levels of a set of 92 pharmaceuticals and 22 inorganic components as well as assessed using subchronic ecotoxicity tests with a macro-alga and a crustacean. Sixty-five pharmaceuticals were detected in the range from 1 ng L(-1) to 7.6 µg L(-1) in incoming and outgoing waters from the four investigated wetlands. Although the sampling design used in the present study lacks the robustness of volume proportional to 24h composite samples, the average estimated removal rates ranged from 42% to 52%, which correlates to previous published values. The effects observed in the ecotoxicity tests with the macro-alga (EC(50)s in the range of 7.5-46%) and the crustacean (LOECs in the range of 11.25-90%) could not be assigned to either pharmaceutical residues or metals, but in general showed that these treatment facilities release water with a relatively low toxic potential, comparable to water that has been treated with advanced tertiary treatments. From the present study it can be concluded that constructed wetlands may provide a complementary sewage treatment option, especially where other treatment is lacking today. To fully remove micro-pollutants from sewage effluent, however, other more advanced treatment technologies are likely needed.

Mercury concentrations in landlocked Arctic char (Salvelinus alpinus) from the Canadian Arctic. Part I: insights from trophic relationships in 18 lakes.

Concentrations of mercury (Hg) have increased slowly in landlocked Arctic char over a 10- to 15-year period in the Arctic. Fluxes of Hg to sediments also show increases in most Arctic lakes. Correlation of Hg with trophic level (TL) was used to investigate and compare biomagnification of Hg in food webs from lakes in the Canadian Arctic sampled from 2002 to 2007. Concentrations of Hg (total Hg and methylmercury [MeHg]) in food webs were compared across longitudinal and latitudinal gradients in relation to delta(13)C and delta(15)N in periphyton, zooplankton, benthic invertebrates, and Arctic char of varying size-classes. Trophic magnification factors (TMFs) were calculated for the food web in each lake and related to available physical and chemical characteristics of the lakes. The relative content of MeHg increased with trophic level from 4.3 to 12.2% in periphyton, 41 to 79% in zooplankton, 59 to 72% in insects, and 74 to 100% in juvenile and adult char. The delta(13)C signatures of adult char indicated coupling with benthic invertebrates. Cannibalism among char lengthened the food chain. Biomagnification was confirmed in all 18 lakes, with TMFs ranging from 3.5 +/- 1.1 to 64.3 +/- 0.8. Results indicate that TMFs and food chain length (FCL) are key factors in explaining interlake variability in biomagnification of [Hg] among different lakes.

Mercury concentrations in landlocked Arctic char (Salvelinus alpinus) from the Canadian Arctic. Part II: influence of lake biotic and abiotic characteristics on geographic trends in 27 populations.

Among-lake variation in mercury (Hg) concentrations in landlocked Arctic char was examined in 27 char populations from remote lakes across the Canadian Arctic. A total of 520 landlocked Arctic char were collected from 27 lakes, as well as sediments and surface water from a subset of lakes in 1999, 2002, and 2005 to 2007. Size, length, age, and trophic position (delta(15)N) of individual char were determined and relationships with total Hg (THg) concentrations investigated, to identify a common covariate for adjustment using analysis of covariance (ANCOVA). A subset of 216 char from 24 populations was used for spatial comparison, after length-adjustment. The influence of trophic position and food web length and abiotic characteristics such as location, geomorphology, lake area, catchment area, catchment-to-lake area ratio of the lakes on adjusted THg concentrations in char muscle tissue were then evaluated. Arctic char from Amituk Lake (Cornwallis Island) had the highest Hg concentrations (1.31 microg/g wet wt), while Tessisoak Lake (Labrador, 0.07 microg/g wet wt) had the lowest. Concentrations of THg were positively correlated with size, delta(15)N, and age, respectively, in 88, 71, and 58% of 24 char populations. Length and delta(15)N were correlated in 67% of 24 char populations. Food chain length did not explain the differences in length-adjusted THg concentrations in char. No relationships between adjusted THg concentrations in char and latitude or longitude were found, however, THg concentrations in char showed a positive correlation with catchment-to-lake area ratio. Furthermore, we conclude that inputs from the surrounding environment may influence THg concentrations, and will ultimately affect THg concentrations in char as a result of predicted climate-driven changes that may occur in Arctic lake watersheds.

Speciation of aluminium, arsenic and molybdenum in excessively limed lakes.

The possible existence of the potentially toxic oxyanions of Al (Al(OH)(4)(-)), As (HAsO(4)(2-)), and Mo (MoO(4)(2-)) was examined in excessively limed lakes. In-situ dialysis (MWCO 1 kDa) was performed in the surface and bottom waters of two excessively limed lakes (pH 7.1-7.7) and one acidic lake (pH approximately 5.4). The dialysable metal concentrations were compared to the equilibrium distribution of species as calculated with the geochemical code Visual MINTEQ incorporating the CD-MUSIC and Stockholm Humic models for complexation onto colloidal ferrihydrite and dissolved organic matter. Arsenic and molybdenum in the excessively limed lakes were to a large extent present in the dialysable fraction (>79% and >92% respectively). They were calculated to exist as free or adsorbed oxyanions. Most of the Al was observed to reside in the colloidal fraction (51-82%). In agreement with this, model predictions indicated aluminium to be present mostly as colloids or bound to dissolved organic matter. Only a small fraction was modelled as Al(OH)(4)(-) ions. In most cases, modelled values were in agreement with the dialysis results. The free concentrations of the three oxyanions were mostly low compared to toxic levels.

Long-term water chemical trends in two Swedish lakes after termination of liming.

Lime treatment has been extensively used as a remedial measure against acidification of surface waters. In view of the decreasing acid deposition, the possible consequences of a termination of liming are discussed intensively in Sweden. This paper presents the results of the first study of long-term effects of termination of liming. The temporal trends in water chemistry were studied in two lakes after termination of liming, in a still-limed lake and in an unlimed reference lake. The lime treatment was intentionally stopped in order to evaluate the effects on water chemistry and biota. After the last liming, pH decreased steadily in both reacidifying lakes until annual mean values stabilised around 5.5-6.0 and 6.2-6.5 respectively. ANC and concentrations of non-marine Ca+Mg decreased after the termination of liming. The decreasing pH resulted in increasing trends of inorganic Al (Al(i)), which during recent years exceeded the lowest known effect level for fish on several occasions. This indicates that the lime treatment may have been terminated to early from an ecological perspective and with respect to the critical load of acidifying substances during the study period. However, during the same time, non-marine sulphate decreased in all lakes in the study and pH and ANC increased in the unlimed reference lake.

Influence of liming on metal sequestration in lake sediments over recent decades.

Sediment profiles from five limed and six reference softwater lakes included in Swedish monitoring programmes were subjected to multi-element analysis to investigate the influence of lime treatment since 1977 on the sequestration of metals in lake sediments. We hypothesised that liming causes increased sedimentation of elements for which the mobility is primarily controlled by pH, e.g. Al, Cd, Co, Ni and Zn, whereas elements that are less influenced by pH fluctuations, e.g. Hg and Pb, are not affected by lime treatment. Further, we introduce a normalisation of metal concentrations with respect to Cu concentration in order to separate the effects of lime treatment from those related to temporal trends in airborne metal deposition or short-term variations in environmental conditions. This approach is shown to emphasise the effect of liming on the sediment accumulation of metals, thus separating it from other sources of variability. We found that liming causes increased sequestration of Al, As, Cd, Co, Fe, Mn, Ni and Zn, in the case of As and Co probably at least partly caused by an increased adsorption to Al, Fe and Mn oxyhydroxides. On the other hand, no influence of lime treatment could be demonstrated for Hg, Pb, Cr, V and P, despite an increase of pH by about two units.

Metal burdens in surface sediments of limed and nonlimed lakes.

Acidification has been shown to increase the concentrations of many metals in lake water as a result of increased mobility at lower pH, whereas liming has been found to decrease lake water metal concentrations. We hypothesise that increased sedimentation as a result of liming increases the metal burdens in the sediments of limed lakes, but especially those that have been treated directly on the lake surface. We also hypothesise that acidification results in decreased metal burdens in the sediments, whereas near neutral reference lakes and lakes where the lime has been applied on wetlands or upstream have intermediate metal burdens in the sediments. In order to test the hypothesis, we statistically compare the areal metal and P burdens in the sediments of four groups of lakes: (1) Mainly surface limed lakes, (2) Mainly upstream/wetland limed lakes, (3) Near neutral reference lakes and, (4) Acidified reference lakes. The statistical analysis reveals that the surface limed group have significantly higher areal burdens of As, Cd, Co and Zn in the sediment compared to the acidified reference group, despite large variations within the groups. The investigation indicates that surface liming increases the areal burdens in the sediments of Cd and Pb, probably of As, Ca and Mn and possibly Co and Zn, whereas acidification decreases the areal burdens in sediments of Cd, Fe, Mn and possibly Co, P and Zn. The results of the study confirm the hypothesis.

Patient satisfaction with anesthesia care: information alone does not lead to improvement.

PURPOSE: To evaluate if information campaigns and introduction of information leaflets lead to an improvement in patient satisfaction with anesthesia care. METHODS: In 2000, we carried out an assessment of patient satisfaction with anesthesia care. "Information/involvement in decision making" was identified as the worst problem area. The three hospitals involved in this study introduced strategies to improve this dimension of patient satisfaction by launching information campaigns, producing or improving information brochures (particularly in hospitals A and C), and by expanding the preanesthetic care unit (hospital B). In 2002, a second survey was carried out. Each of the hospitals sent questionnaires to 600 elective surgery patients after discharge. We compared the total problem scores (the percentage of patients who responded that a problem was present) and the problem scores for the dimension 'information/involvement in decision making' between 2000 and 2002. RESULTS: The total problem score (mean in %, 95% confidence interval) for all three hospitals together remained unchanged [19% (1)], as well as the problem scores for each hospital [hospital A 16% (1), hospital B 21% (1), hospital C 20% (1)]. The problem score for 'information/involvement in decision making' remained unchanged also: 31% (29-33) in 2000 compared to 28% (26-30) in 2002. CONCLUSION: Information campaigns and the introduction of information leaflets alone do not improve patient satisfaction with anesthesia care.

Effects of experimental acidification on mobilisation of metals from sediments of limed and non-limed lakes.

In order to study the influence of pH on the mobilisation of metals from lake sediments, intact sediment cores with overlying water were sampled from one lime treated lake and one acidified lake. The overlying water of two cores from each lake was successively acidified to pH 4.2 over a period of 3 months. In the acid treated samples from the limed lake, the initial concentrations of Al, Cd, Mn, Pb and Zn in the overlying water were generally lower and the final concentrations were higher than in the acid treated samples from the acidified lake. The labile inorganic fraction of Al (Al(i)) was increasingly dominating as pH decreased. Redox potential and pH in the sediment indicated that the upper two centimetres were involved in the exchange reactions. The experiment showed that mobilisation of metals from sediments can occur and the results indicated that mobilisation could contribute to increased concentrations of metals in lake water during reacidification of formerly lime treated lakes.

Use of ethylenediaminetetraacetic acid in pulp mills and effects on metal mobility and primary production.

Over the last decade, the use of ethylenediaminetetraacetic acid (EDTA) has increased by a factor of three within the Swedish pulp industry. The effects of pulp mill wastewater in combination with EDTA on metal mobility and the consequences for ecologically relevant organisms have been studied. Ethylenediaminetetraacetic acid was added to pulp mill effluent water in the laboratory and compared to wastewater without EDTA. Degradation of the water was followed over a experimental period up to eight weeks and samples were taken five times for chemical analysis and at the beginning and the end for biological tests. Half a year later, the experiment was repeated. The results from both experiments showed that EDTA markedly increased the solubility of zinc, cadmium, lead, iron, nickel, and copper, whereas the solubility of vanadium, molybdenum, thallium, arsenic, and chromium was not changed by the presence of EDTA. No measurable degradation of EDTA occurred even after 5.5 months. The toxicity of the pulp mill effluent water was low, and only a slight toxic effect was observed on the reproduction of Ceramium strictum. The most pronounced effect was a stimulation in the growth of three algal species in 5 to 20% (v/v) total effluent wastewater with and without EDTA. The presence of EDTA in the dissolved fraction of the pulp mill effluent water increased the growth stimulation in 20 to 40% (v/v), possibly because of the increased availability of essential metals like iron, zinc, and copper. The capacity of the pulp mill wastewater to support algal growth was nearly as good as a rich nutrient medium for algae. The combination of poorly degradable EDTA and the increasing availability of metals might further enhance eutrophication in the recipient areas of pulp mills.