FACTORS INFLUENCING ACUTE TOXICfrY OF COAL ASH TO RAINBOW TROUT (SALMO GAIRDNERI) AND BLUEGILL SUNFISH (LEPOMIS MACROCHIRUS)1

ABSTRACT: The potentially toxic components in coal ash (ash particles, heavy metals) were evaluated in laboratory static, acute (96 hr) bioassays, both separately and in various combinations with extreme pH (5.0 and 8.5), using rainbow trout (Salmo gairdneri) and bluegifi sunfish (Lepomis macrochirus). Ash particle morphology and metal distribution anlaysis, using electron microscopy and surface-subsurface analysis by ion microscopy, showed that metals could be either clumped or evenly distributed on the surface of fly ash. Surface enrichment on fly ash particles from electrostatic precipitators, as measured by ion microscopy, was found for cadmium, copper, chromium, nickel, lead, mercury, titanium, arsenic, and selenium. Bottom (heavy) ash was not acutely toxic to either fish species at concentrations of up to 1500 mg/l total suspended solids (TSS) at pH 5.0, 7.5, or 8.5. Fly ash particles were not acutely toxic to blue-gill at levels up to 1360 mg/l TSS. Rainbow trout were highly sensitive to fly ash (25 to 60 percent mortality) at concentrations of 4.3 to 20.5 mg/I TSS when dissolved metal availability was high but were not sensitive at higher particulate concentrations (58 to 638 mg/I TSS) when dissolved metals were low. When metals were acid-leached from fly ash prior to testing, no rainbow trout mortality occurred at TSS concentrations of up to 2,350 mg/l TSS. When the percent of dissolved metal was high (e.g., 50–90 percent of the total), fish mortality was increased. Rainbow trout were nearly two orders of magnitude more sensitive than bluegill when subjected to a blend of cadmium, chromium, copper, nickel, lead, and zinc. The two species were similar in their acute sensitivity to acidic pH at levels at or below 4.0 and alkaline pH of 9.1. If the pH of coal ash effluent is contained within the range 6.0 to 9.0, acute toxicity to fish can be attributed to trace element availability from fly ash but not heavy ash. Control of holding pond and effluent pH and maximizing pond residence time are important strategies for minimizing effects of ash pond discharges on fish.     

太阳鱼脑乙酰胆碱酯酶的分离纯化

采用硫酸铵沉淀–普鲁卡因胺亲和柱层析方法,对太阳鱼(Lepomis gibbosus)脑部乙酰胆碱酯酶分离纯化,纯化倍数为234倍,回收率为25.67%,经SDS-PAGE电泳检测,呈现单一的条带,相对分子质量约为68 000,表明其纯度达到电泳纯.     

TEMPERATURE BEHAVIOR OF THE BLUESPOTTED SUNFISH ENNEACANTHUS GLORIOSUS (HOLBROOK), WITH AN EVALUATION OF THE INTERPRETATION OF THERMAL BEHAVIOR DATA1

The bluespotted sunfish, Enneacanthus gloriosus (Holbrook), had a final temperature preferendum of 31.5 C. Fish acclimated to 30 C avoided 36 C. The analysis of acute temperature preference data and the relationship between final temperature preferendum and upper avoidance temperatures are discussed.