Mercury and metal(loid) deposition to remote Nova Scotia lakes from both local and distant sources.

Kejimkujik National Park, in Nova Scotia, Canada, is a sensitive region for metal(loid) contamination, such as mercury, in part due to long-range atmospheric deposition from global and regional industrial centers. The region is remote from industrial centres, but is downwind of major pollution sources in the Eastern United States and Canada, and historically had numerous gold mining sites. Due to a paucity of long-term atmospheric deposition monitoring in this region, little is known about the response of Kejimkujik lakes to multiple changing global, regional and local atmospheric Hg and metal(loid) sources. Here, we used multiple lake sediment cores to reconstruct anthropogenic depositional fluxes of metal(loid)s of concern for the last ~210years. Results showed that Kejimkujik lake sediments are highly enriched in lead (Pb), antimony (Sb) and tin (Sn), with post-industrial metal(loid) concentrations being >4-fold greater than natural baseline levels (prior to ~1800) and moderately enriched in silver (Ag), bismuth (Bi), cadmium (Cd), copper (Cu), mercury (Hg), rubidium (Rb), tellurium (Te), thallium (Tl), vanadium (V), tungsten (W) and zinc (Zn), with post-industrial metal(loid) concentrations being between 1.5 and 4-fold greater than natural baseline levels (prior to ~1800). Lake sediment core reconstructions of total atmospheric Hg deposition matched well with Hg wet deposition monitoring data from the overlapped period (1997-2010) being 9.1±2.7µg/m2/yr and 7.0±0.7µg/m2/yr respectively. Lakes closest to historic gold mining sites show spikes in Ag, Cd, Sb, Tl, Zn and W during mining periods (~1880 and 1950). Most of the enriched metal(loid)s (EF >1.5) (Ag, Bi, Cu, Hg, Pb, Sb, Sn, V and W) do not appear affected by redox and remobilisation issues. For the other enriched metal(loid)s (EF >1.5) (Cd, Tl, and Zn), remobilisation from upper sediments appears to be occurring within these acidic and DOC rich Kejimkujik lakes.

Meltwater from snow contaminated by oil sands emissions is toxic to larval fish, but not spring river water.

To assess the toxicity of winter-time atmospheric deposition in the oil sands mining area of Northern Alberta, embryo-larval fathead minnow (Pimephales promelas) were exposed to snowmelt samples. Snow was collected in 2011-2014 near (<7km) oil sands open pit mining operations in the Athabasca River watershed and at sites far from (>25km) oil sands mining. Snow was shipped frozen back to the laboratory, melted, and amended with essential ions prior to testing. Fertilized fathead minnow eggs were exposed (<24h post-fertilization to 7-16days post-hatch) to a range of 25%-100% snowmelt. Snow samples far from (25-277km away) surface mining operations and upgrading facilities did not affect larval fathead minnow survival at 100%. Snow samples from sites near surface mining and refining activities (<7km) showed reduced larval minnow survival. There was some variability in the potencies of snow year-to-year from 2011 to 2014, and there were increases in deformities in minnows exposed to snow from 1 site on the Steepbank River. Although exposure to snowmelt from sites near oil sands surface mining operations caused effects in larval fish, spring melt water from these same sites in late March-May of 2010, 2013 and 2014 showed no effects on larval survival when tested at 100%. Snow was analyzed for metals, total naphthenic acid concentrations, parent PAHs and alkylated PAHs. Naphthenic acid concentrations in snow were below those known to affect fish larvae. Concentrations of metals in ion-amended snow were below published water quality guideline concentrations. Compared to other sites, the snowmelt samples collected close to mining and upgrading activities had higher concentrations of PAHs and alkylated PAHs associated with airborne deposition of fugitive dusts from mining and coke piles, and in aerosols and particles from stack emissions. CAPSULE: Snow collected close to oil sands surface mining sites is toxic to larval fathead minnows in the lab; however spring melt water samples from the same sites do not reduce larval fish survival.

The Opioid Abuse Risk Screener predicts aberrant same-day urine drug tests and 1-year controlled substance database checks: A brief report.

The Opioid Abuse Risk Screener was developed to support well-informed decision-making in opioid analgesic prescribing by extending the breadth of psychiatric risk factors evaluated relative to other non-clinician-administered measures. We examined the preliminary predictive validity of the Opioid Abuse Risk Screener relative to the widely used Screener and Opioid Assessment for Patients with Pain-Revised in predicting aberrant urine drug tests and controlled substance database checks. The Opioid Abuse Risk Screener is significantly different from the Screener and Opioid Assessment for Patients with Pain-Revised in predicting aberrant same-day urine drug tests (Z = 2.912, p = 0.0036) and controlled substance database checks within 1 year of assessment (Z = 3.731, p = 0.0002). Promising preliminary analyses using machine learning methods are also discussed.

Importance of open marine waters to the enrichment of total mercury and monomethylmercury in lichens in the Canadian High Arctic.

Caribou, which rely on lichens as forage, are a dietary source of monomethylmercury (MMHg) to many of Canada's Arctic Aboriginal people. However, little is understood about the sources of MMHg to lichens in the High Arctic. We quantified MMHg, total mercury (THg) and other chemical parameters (e.g., marine and crustal elements, δ(13)C, δ(15)N, organic carbon, calcium carbonate) in lichen and soil samples collected along transects extending from the coast on Bathurst and Devon islands, Nunavut, to determine factors driving lichen MMHg and THg concentrations in the High Arctic. Lichen MMHg and THg concentrations ranged from 1.41 to 17.1 ng g(-1) and from 36.0 to 361 ng g(-1), respectively. Both were highly enriched over concentrations in underlying soils, indicating a predominately atmospheric source of Hg in lichens. However, MMHg and THg enrichment at coastal sites on Bathurst Island was far greater than on Devon Island. We suggest that this variability can be explained by the proximity of the Bathurst Island transect to several polynyas, which promote enhanced Hg deposition to adjacent landscapes through various biogeochemical processes. This study is the first to clearly show a strong marine influence on MMHg inputs to coastal terrestrial food webs with implications for MMHg accumulation in caribou and the health of the people who depend on them as part of a traditional diet.

Unilateral adrenal enlargement due to Histoplasma capsulatum.

Human infection with Histoplasma capsulatum runs the gamut from asymptomatic to disseminated disease. CT-directed fine-needle aspiration of bilaterally enlarged adrenal glands has been used in diagnosing serious infections with this ubiquitous organism. Three cases have previously been reported in which H. capsulatum infection caused unilateral adrenal enlargement; this enlargement was diagnosed post-mortem. We describe three patients with unilateral adrenal enlargement due to H. capsulatum whose conditions were diagnosed antemortem. We encourage clinicians to include infection with H. capsulatum as well as other granulomatous diseases and tumors in the differential diagnosis of unilateral adrenal enlargement.

Rocky Mountain spotted fever. A clinical review based on 48 confirmed cases, 1943-1986.

We reviewed 48 cases of Rocky Mountain spotted fever seen between 1943 and 1986. The data provided a view of the diverse presentations and manifestations of this disease. Exposure to a rural environment or to dogs was the rule, and over two-thirds of patients specifically remembered tick exposure. Clinical presentation was highly variable. Although fever, headache, and rash were each common, only 62% had the complete triad. Neurological symptoms and signs were common in this series. Cerebrospinal fluid abnormalities, particularly leukocytosis, were the rule in those patients who underwent lumbar puncture. Neurologic sequelae occurred in several patients. Multiple other organ systems were involved at presentation or during the course of illness--gastrointestinal, cardiovascular, pulmonary, renal, muscular, hematologic. These manifestations could, and often did, confuse physicians seeing these patients initially. They further accounted for the diverse complications seen. Outcome was good in this series. Mortality rate was 2%, and most patients recovered without sequelae. However, morbidity during hospitalization was often severe. Even in an endemic area with high index of suspicion, the diagnosis of RMSF was often delayed, usually because of failure of the physician to consider this possibility at initial presentation. This series emphasizes the importance of considering RMSF in any febrile patient in an endemic area, regardless of "atypical" presentation or apparent lack of tick exposure.

Analysis of early infectious complications after autologous bone marrow transplantation.

We reviewed the hospital course of 35 patients who underwent autologous bone marrow transplantation. Fever and profound neutropenia developed in all. Microbiologically confirmed infection developed in 22 patients, and unconfirmed but clinically evident infection developed in six. A bacterial infection developed in 21 patients (most commonly bacteremia without a detectable focus). Mucocutaneous fungal (12 patients) and viral (13 patients) infections were common, whereas invasive fungal (two patients) and viral (one patient) infections were uncommon. New pulmonary infiltrates developed in seven patients. Six deaths occurred during the initial hospitalization for transplantation, only one of which was directly attributable to infection. Stepwise logistic regression analysis retained male gender, total body irradiation, administration of trimethoprim/sulfamethoxazole, and development of mucositis or diarrhea as predictors of decreased survival, whereas higher pretreatment albumin levels and the administration of oral nonabsorbable antifungals were associated with an increased likelihood of survival. A comparison of these infectious complications with those found in allogeneic bone marrow transplant recipients shows similarities and differences with potentially important implications for patient management.

Analysis of humoral and phagocytic defenses against Streptococcus pneumoniae serotypes 1 and 3.

To better define relationships among pneumococcal anticapsular antibodies, opsonophagocytosis, and in vivo mouse protection, we measured these functions in sera from healthy individuals who had not received pneumococcal vaccine. For serotype 1 pneumococci, the level of antibody measured by radioimmunoassay did not predict mouse protection, as has been noted by others. For some sera, opsonic requirements for antibody and complement could be clearly demonstrated and a strong correlation obtained between concentration of antibody and degree of phagocytic killing. However, for most sera, antibody concentration did not correlate with opsonic activity, as measured by phagocytic bactericidal assay or uptake of radiolabeled bacteria. Sera with high concentrations of anticapsular antibody did not always support in vitro bacterial killing by leukocytes. Conversely, highly opsonic sera did not necessarily have substantial levels of measurable antibody. Moreover, in vitro opsonophagocytic activity failed to predict in vivo protection; sera could be opsonic in vitro but not protective in vivo and vice versa. For serotype 3 pneumococci, antibody concentrations correlated strongly with mouse protective titers, as has been noted by others for type 3. Opsonophagocytosis, as measured by leukocyte bactericidal activity, required both complement and heat-stable substance(s) present in high-antibody sera, presumably antibody. Furthermore, increasing concentrations of serum enhanced phagocytic killing in a fashion that could be correlated with anticapsular antibody content. However, correlation with opsonophagocytosis was not so strong as with mouse protection, and there was no correlation between antibody concentration and opsonization as measured by uptake of radiolabeled bacteria. These observations suggest that opsonophagocytosis (with the definitive end point of bacterial killing) cannot be the standard against which to measure antibody concentrations. Furthermore, host protective mechanisms against pneumococci remain to be clearly defined. Even if opsonization by anticapsular antibody is the primary mechanism, there is need for development of improved functional assays of protection.