Selenium Bioaccumulation in Stocked Fish as an Indicator of Fishery Potential in Pit Lakes on Reclaimed Coal Mines in Alberta, Canada

Pit lakes are a common reclamation strategy for open pit mines; however, there is a concern about their water quality and suitability as fish habitat because they are often contaminated by metals or metalloids. This study assessed the exposure of fish and invertebrates to selenium (Se) and other metals and metalloids in pit lakes formed by open pit coal mining in Tertiary (thermal coal) and in Cretaceous (metallurgical coal) bedrock. Juvenile hatchery rainbow trout, Oncorhynchus mykiss, and brook trout, Salvelinus fontinalis, were stocked into two thermal coal pit lakes (water Se < 2 μg/L, low water Se) and two metallurgical coal pit lakes (water Se > 15 μg/L, high water Se). Se accumulation in stocked fish and concentrations in invertebrates were characterized over a period of 2 years. In the metallurgical pits, invertebrates had higher Se concentrations and fish accumulated Se to higher levels (exceeding USEPA tissue Se guidelines) than biota in the thermal pits. Rainbow and brook trout accumulated similar concentrations of Se in their muscle and exhibited a similar relationship between whole-body and muscle Se concentrations. These results may be used by resource managers to assess compliance with whole-body tissue Se guidelines and to determine if pit lakes in coal mining areas pose a significant Se risk to wildlife or human health. The high Se exposure in metallurgical coal pits indicates that under the current mining and reclamation strategy, these lakes are not suitable for management as recreational “put and take” fisheries.     

Treatment of creosote-contaminated groundwater in vegetated sorption/bio-barriers in cold climates

Permeable barriers are structures installed in situ to treat contaminated groundwater. Pollutants are removed as contaminated groundwater flows through a barrier material. A compost/sand barrier and a plant covered permeable barrier with soil/sand and peat/sand were tested in pilot-scale to treat creosote-contaminated groundwater by sorption and biological removal in situ. Outlet concentrations of the barriers were consistently low during the 29 months of operation. Although sorption sites were filled up with polycyclic aromatic hydrocarbons, they seemed to be regenerated because of biodegradation under aerobic conditions. The vegetated section was least efficient, probably because of lack of oxygen, hence it could not be determined if the plants had a positive effect. As long as biodegradation is efficient the barrier is expected to function for several more years.     

Risk of Myxobolus cerebralis infection to rainbow trout in the Madison River, Montana, USA.

Myxobolus cerebralis, the parasite that causes salmonid whirling disease, has had detrimental effects on several salmonid populations in the Intermountain West, including the rainbow trout in the Madison River, Montana, USA. The goal of this study was to examine relationships among characteristics of the environment, Tubifex tubifex (the alternate host) populations, and rainbow trout whirling disease risk in the Madison River. Environmental characteristics were measured in side channels of the Madison River, and differences were described with a principal components analysis. The density of T. tubifex, the prevalence of infection in T. tubifex, and the density of infected T. tubifex were determined for the side channels using benthic core samples and examination of live tubificids for infection. The site-specific contribution to whirling disease risk in the side channels was determined using in situ exposures of sentinel rainbow trout. Regression analyses were used to determine correlations among these characteristics. Side channels differed in site-specific contribution to rainbow trout whirling disease risk, which was positively correlated to the density of infected T. tubifex. Side channels with fine sediments and lower water temperatures made greater site-specific contribution to whirling disease risk and had higher densities of infected T. tubifex than side channels with coarser sediments and higher temperatures. The ability to characterize areas of high whirling disease risk is essential for improving our understanding of the dynamics of M. cerebralis such that appropriate management strategies can be implemented. In addition, this study provides a model of how the disease ecology of complex aquatic parasites can be examined when the influential processes operate on different spatial scales.     

The bottle bill: Perceptions of inconvenience,litter and willingness to pay in Western New York

Returnable container legislation in New York requires that all carbonated soft drink and beer containers carry a minimum five-cent deposit and bans detachable metal tabs and nonbiodegradable plastic loops. A continuing environmental policy issue is whether the benefits of a less-littered environment and reduction of solid waste are greater than the increase in retail prices and inconvenience costs to the consumer. This paper reports consumer estimates of the inconvenience of returning beverage containers to a store, perceptions of the litter problem, and willingness to pay to reduce litter in Wellsville, NY. Nearly two-thirds of the respondents believe that litter is a major problem. Most important, 76% of those interviewed reported they were willing to pay 10 cents, and 42% thought they were willing to pay 15 cents to reduce litter. Nearly one-half of the respondents did not think returning containers to the store would be inconvenient, but 22% stated that the process would be inconvenient. Correlations between the attitudes and income, education, and age are reported. These findings will be of interest to New Yorkers as they evaluate the bottle bill, as well as to individuals in other states considering returnable container legislation.     

Determination of maternal serum acetylcholinesterase in pregnancies with fetal neural tube defects

We have investigated the occurrence of acetylcholinesterase (AChE) (E.C.3.1.1.7) in fetal serum, amniotic fluid and maternal serum using an immuno-chemical assay-technique employing both polyclonal and monoclonal antibodies. Fetal serum had increased amounts of AChE, which is due to an increase in the 10.5S form of the enzyme. This form was also found in amniotic fluids of pregnancies with a fetal neural tube defect (NTD), but not in normal amniotic fluid. The increase in amniotic fluid AChE was however, not reflected in the maternal serum.     

Atmospheric nitrous oxide: patterns of global change during recent decades and centuries

Data from weekly global measurements of nitrous oxide from 1981 to the end of 1996 are presented. The results show that there is more N2O in the northern hemisphere by about 0.7 +/- 0.04 ppbv, and the Arctic to Antarctic difference is about 1.2 +/- 0.1 ppbv. Concentrations at locations influenced by continental air are higher than at marine sites, showing the existence of large land-based emissions. For the period studied, N2O increased at an average rate of about 0.6 ppbv/year (approximately 0.2%/year) although there were periods when the rates were substantially different. Using ice core data, a record of N2O can be put together that goes back about 1000 years. It shows pre-industrial levels of about 287 +/- 1 ppbv and that concentrations have now risen by about 27 ppbv or 9.4% over the last century. The ice core data show that N2O started increasing only during the 20th century. The data presented here represent a comprehensive view of the present global distribution of N20 and its historical and recent trends.     

Reduction of dioxins and furanes by spray dryer absorption from incinerator flue gas

Reduction of gas phase polychlorinated dibenzodioxins and dibenzofuranes by spray dryer absorption from incinerator flue gas has been investigated. Results from pilot plant and industrial scale spray absorption systems are reported. The results show that conditions for very high removal efficiencies exist for all isomer groups. Total removal above 95% has been achieved.