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.

Cognition, MRS neurometabolites, and MRI volumetrics in non-neuropsychiatric systemic lupus erythematosus: preliminary data.

OBJECTIVE: To correlate cognitive dysfunction with structural and neurometabolic brain findings in patients with non-neuropsychiatric systemic lupus erythematosus (non-NPSLE). BACKGROUND: Over 25% of non-NPSLE patients have cognitive dysfunction, but the cerebral basis of this observation is not well understood. METHOD: Seven patients with non-NPSLE and seven control subjects were given a series of neuropsychological tests and neuroimaging with magnetic resonance imaging and magnetic resonance spectroscopy. Analyses of cognitive function and structural and neurometabolic measures of the brain were performed. RESULTS: Compared with controls, the non-NPSLE patients were significantly impaired on a global cognitive impairment index (CII). No significant differences between the groups were found in choline/creatine (Ch/Cr), N-acetylaspartic acid/Cr, or hippocampal volumes. Ch/Cr was highly associated with CII across the sample. CONCLUSIONS: This is the first study to correlate cognitive impairment with an increase in Ch/Cr ratio among patients with SLE. These results, although preliminary, suggest that changes in cerebral white matter may be important in determining the subtle cognitive impairment that may occur in patients with SLE, even in the absence of neuropsychiatric symptoms.

Mutagenicity tests of diflubenzuron in the micronucleus test in mice, the L5178Y mouse lymphoma forward mutation assay, and the Ames Salmonella reverse mutation test.

Diflubenzuron, one of a new class of pesticides believed to act via inhibition of chitin synthesis in the developing insect cuticle, was tested for possible mutagenic activity using the micronucleus test in mice, the L5178Y mouse lymphoma forward mutation test at the thymidine kinase locus, and the Ames Salmonella/microsome reverse mutation test. No mutagenic effect was found.