Thomas R. Garland

Comparative metabolic behavior and interrelationships of Tc and S in soybean plants

The comparative behavior of sulfur (S) and technetium (Tc) in soybean seedlings shows gross subcellular distributions to be similar for these oxyanions. More than 75% of the tissue-deposited Tc remains soluble and extractable. Differences in Tc fixation/incorporation were noted for the nuclear and chloroplast fractions of leaf and root cells. Pulse studies showed that soluble protein and nitrate reductase levels rose in response to Tc accumulation by sink leaves but not source leaves. In vitro assay of chloroplast-based S reduction and incorporation systems showed Tc to be reduced and incorporated into amino nitrogen-containing products. A hypothesis related to the metabolic behavior of Tc in plants is presented.

Alkylpyridines in surface waters, groundwaters, and subsoils of a drainage located adjacent to an oil shale facility.

Soil extracts, surface waters, and groundwaters were analyzed for the presence of water-soluble organic compounds in a drainage located adjacent to the retorted shale disposal pile a t the Department of Energy Anvil Points Oil Shale Facility, Rifle, CO. The c3-C~ alkylpyridines were positively identified in water from one of several alluvial wells, and in a surface seep. Surface waters of the stream below the seep contained alkylpyridines but in lower concentration. Alkylpyridines were detected in a moist subsoil sampled adjacent to the well, in retort water, and in aqueous extracts of shale oil. They were not detected in aqueous extracts of raw shale, retorted shale, or Prudhoe Bay crude oil. The absence of the alkylpyridines in a petroleum suggests that the compounds may be unique to shale oils, perhaps allowing their use as diagnostic indicators of water in contact with shale oils a t sites of oil shale production and processing.

Drilling fluids and the arctic tundra of Alaska: Assessing contamination of wetlands habitat and the toxicity to aquatic invertebrates and fish

Drilling for oil on the North Slope of Alaska results in the release of large volumes of used drilling fluids into arctic wetlands. These releases, usually come from regulated discharges or seepage from reserve pits constructed to hold used drilling fluids. A study of five drill sites and their reserve pits showed an increase in common and trace elements and organic hydrocarbons in ponds near-to and distant from reserve pits. Ions elevated in water were Ba, Cl, Cr, K, SO4 and Zn. Concentrations of Cu, Cr, Fe, Pb, and Si in sediments were higher in near and distant ponds than in control ponds. The predominant organics in drill site waters and sediments consisted of aromatic and paraffinic hydrocarbons characteristic of petroleum or a refined product of petroleum. In 96-hr exposures in the field, toxicity toDaphnia Middendorffiana was observed in water from all reserve pits, and from two of five near ponds, but not from distant ponds. In laboratory tests withDaphnia magna, growth and reproduction were reduced in dilutions of 2.5% drilling fluid (2.5 drilling fluid: 97.5 dilution water) from one reserve pit, and 25% drilling fluid from a second. Growth and reproduction were not affected at these dilutions of fluid from the other three reserve pits. Additional regulations—such as an upper limit on aromatic hydrocarbon content and toxicity to sensitive organisms —are needed to improve safety for aquatic organisms in habitats receiving used drilling fluids.

SLOW-RELEASE RADIOISOTOPE IMPLANTS AS INDIVIDUAL MARKERS FOR CARNIVORES

We developed a technique that identifies an individual animal by labeling its excreta. Various gamma-emitting radioisotopes were incorporated into implantable discs made of polylactic acid (PLA), a biodegradable polymer. Laboratory testing and field studies with coyotes (Canis latrans) demonstrated that the 6 radioisotopes evaluated were released from the subcutaneously-implanted polymer at a relatively constant rate after an initial burst phase and allowed a minimum marking period of 6 months. Prototype slow-release implants were used in a field study of coyotes to estimate population abundance, estimate home range, assess individual diets, and examine social and scent-marking behavior. The implant technique has potential widespread application in studies of wild carnivores.

Leaching of retorted oil shale: assessing the toxicity to Colorado squawfish, fathead minnows, and two food-chain organisms

Abstract Development of a large shale-oil industry in Colorado, Utah, and Wyoming would result in disposal of large volumes of retorted shale. Water percolating through these wastes could leach toxicants into surface waters of the upper Colorado River system. Leachate from field lysimeters containing shale that had gone through the Paraho retorting process 6 years before had high concentrations of K, Li, Mg, Mo, Na, SO 4, and NO 3. Total concentrations of organics in leachate were low; nitrogen-containing aromatic hydrocarbons approximated background concentrations. In 96-h exposures, undiluted leachate was not toxic to fathead minnows Pimephales promelas or Colorado squawfish Ptychocheilus lucius, and was only slightly toxic to the mayfly Hexagenia bilineata and to Daphnia magna. In 30-d exposures to different concentrations of the leachate, a concentration of 6:94 (percent leachate:percent dilution water) caused reduced growth of fathead minnows and reduced survival of mayflies. The highest test concent...

Concentration of orally administered and chronically fed 95mTc in Japanese quail eggs.

A chronic feeding study using 95mTc incorporated into alfalfa and an acute study where 95mTc was amended to alfalfa showed that about 8.4% of ingested Tc was transferred to eggs. After 10 days of chronic feeding, 80% of the Tc was in yolk, 20% in albumin and less than 1% in shell and associated membranes. At necropsy, technetium concentrations in the three largest oocytes were nearly equal. The biological half-time for Tc was about one to two days in acute studies. Results from the chronic feeding study also indicated that Tc levels in albumin reach a maximum between three and five days while maximum yolk concentration is attained in about six to seven days. Albumin concentrations declined about 20-50% after Day 6.