Radionuclides in deer and elk from Los Alamos National Laboratory and the doses to humans from the ingestion of muscle and bone.

This paper summarizes radionuclide concentrations (3H, 90Sr, 137Cs, 238Pu, 239,240Pu, 241Am, and totU) in muscle and bone tissue of mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus) collected from Los Alamos National Laboratory (LANL), Los Alamos, New Mexico, lands from 1991 through 1998. Also, the committed effective dose equivalent (CEDE) and the risk of excess cancer fatalities (RECF) to people who ingest muscle and bone from deer and elk collected from LANL lands were estimated. Most radionuclide concentrations in muscle and bone from individual deer (n = 11) and elk (n = 22) collected from LANL lands were either at less than detectable quantities (where the analytical result was smaller than two counting uncertainties) and/or within upper (95%) level background (BG) concentrations. As a group, most radionuclides in muscle and bone of deer and elk from LANL lands were not significantly higher (p < 0.10) than in similar tissues from deer (n = 3) and elk (n = 7) collected from BG locations. Also, elk that had been radio collared and tracked for two years and spent an average time of 50% of LANL lands were not significantly different in most radionuclides from road kill elk that have been collected as part of the environmental surveillance program. Overall, the upper (95%) level net CEDEs (the CEDE plus two sigma for each radioisotope minus background) at the most conservative ingestion rate (50 lbs of muscle and 13 lbs of bone) were as follows: deer muscle = 0.22 mrem y-1 (2.2 microSv y-1), deer bone = 3.8 mrem y-1 (38 microSv y-1), elk muscle = 0.12 mrem y-1 (1.2 microSv y-1), and elk bone = 1.7 mrem y-1 (17 microSv y-1). All CEDEs were far below the International Commission on Radiological Protection guideline of 100 mrem y-1 (1000 microSv y-1), and the highest muscle plus bone net CEDE corresponded to a RECF of 2E-06, which is far below the Environmental Protection Agency upper level guideline of 1E-04.     

Toxic effects of endocrine disrupters on freshwater sponges: common developmental abnormalities

Endocrine disrupters are of substantial concern, in large part because effects of these compounds on the growth and development of many aquatic organisms are unknown. We examined toxic effects of three substances (ethylbenzene, nonylphenol, and bisphenol A), that are known to be hormonally active in many animals, on growth and development of two species of freshwater sponge. A common developmental abnormality was observed when sponges were treated with each of these compounds. The three compounds also caused significant reductions in growth rates. Lower concentrations resulted in malformed water vascular systems in several replicates. The utility of freshwater sponge bioassays is discussed as it relates to understanding possible mechanisms of action of endocrine disrupters on aquatic invertebrates.     

Pilot-scale aerated submerged biofilm reactor for organics removal and nitrification at cold temperatures.

This research describes pilot-scale experiments for efficient removal of dissolved organic and nitrogen compounds in domestic wastewater using aerated submerged biofilm (ASBF) reactors. These reactors could enhance the performance of shallow wastewater treatment lagoons through the addition of specially designed structures. The structures are designed to encourage the growth of a nitrifying bacterial biofilm on a submerged surface. They also force the direct contact of rising air bubbles against the submerged biofilm. This direct gas-phase contact is postulated to increase the oxygen transfer rate into the biofilm and increase the microclimate mixing of water, nutrients, and waste products into and out of the biofilm. This research investigated the efficiency of dissolved organic matter and ammonia-nitrogen removals. Specifically, the effects of cold temperatures on the dissolved organic matter and ammonia-nitrogen performance of the ASBF pilot plant (see Figure 1) was investigated for the batch system. Over a period of 3.5 months, a total of 11 batch runs were performed. By the fourth run, the biofilm had matured to the point that it consumed all the ammonia in 40 hours. On the ninth run, the air supply was left off as a control run. This time, the ammonia was barely consumed, with the level dropping from 24 to 18 mg/L in 40 hours. By the middle of December, the average water temperature during the runs had dropped to approximately 6 degrees C and, at one point, was as low as 3.3 degrees C. The biofilm continued to perform even at these low temperatures, reducing ammonia levels from approximately 25 mg/L to basically zero within 40 to 48 hours.     

Radionuclides and trace elements in fish collected upstream and downstream of Los Alamos National Laboratory and the doses to humans from the consumption of muscle and bone.

The purpose of this study was to determine radionuclide and trace element concentrations in bottom-feeding fish (catfish, carp, and suckers) collected from the confluences of some of the major canyons that cross Los Alamos National Laboratory (LANL) lands with the Rio Grande (RG) and the potential radiological doses from the ingestion of these fish. Samples of muscle and bone (and viscera in some cases) were analyzed for 3H, 90Sr, 137Cs, totU, 238Pu, 239,240Pu, and 241Am and Ag, As, Ba, Be, Cr, Cd, Cu, Hg, Ni, Pb, Sb, Se, and Tl. Most radionuclides, with the exception of 90Sr, in the muscle plus bone portions of fish collected from LANL canyons/RG were not significantly (p < 0.05) higher from fish collected upstream (San Ildefonso/background) of LANL. Strontium-90 in fish muscle plus bone tissue significantly (p < 0.05) increases in concentration starting from Los Alamos Canyon, the most upstream confluence (fish contained 3.4E-02 pCi g-1 [126E-02 Bq kg-1]), to Frijoles Canyon, the most downstream confluence (fish contained 14E-02 pCi g-1 [518E-02 Bq kg-1]). The differences in 90Sr concentrations in fish collected downstream and upstream (background) of LANL, however, were very small. Based on the average concentrations (+/- 2SD) of radionuclides in fish tissue from the four LANL confluences, the committed effective dose equivalent from the ingestion of 46 lb (21 kg) (maximum ingestion rate per person per year) of fish muscle plus bone, after the subtraction of background, was 0.1 +/- 0.1 mrem y-1 (1.0 +/- 1.0 microSv y-1), and was far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem y-1 (1000 microSv y-1). Of the trace elements that were found above the limits of detection (Ba, Cu, and Hg) in fish muscle collected from the confluences of canyons that cross LANL and the RG, none were in significantly higher (p < 0.05) concentrations than in muscle of fish collected from background locations.     

Radionuclides and trace elements in fish collected upstream and downstream of Los Alamos national laboratory and the doses to humans from the consumption of muscle and bone

Abstract

The purpose of this study was to determine radionuclide and trace element concentrations in bottom‐feeding fish (catfish, carp, and suckers) collected from the confluences of some of the major canyons that cross Los Alamos National Laboratory (LANL) lands with the Rio Grande (RG) and the potential radiological doses from the ingestion of these fish. Samples of muscle and bone (and viscera in some cases) were analyzed for ³H, ⁹⁰Sr, ¹³⁷Cs, ^totU, ²³⁸Pu, ^239,240Pu, and ²⁴¹Am and Ag, As, Ba, Be, Cr, Cd, Cu, Hg, Ni, Pb, Sb, Se, and Tl. Most radionuclides, with the exception of ⁹⁰Sr, in the muscle plus bone portions of fish collected from LANL canyons/RG were not significantly (p<0.05) higher from fish collected upstream (San Ildefonso/background) of LANL. Strontium‐90 in fish muscle plus bone tissue significantly (p<0.05) increases in concentration starting from Los Alamos Canyon, the most upstream confluence (fish contained 3.4E‐02 pCi g^‐1 [126E‐02 Bq kg^‐1]), to Frijoles Canyon, the most downstream confluence (fish contained 14E‐02 pCi g^‐1 [518E‐02 Bq kg^‐1]). The differences in ⁹⁰Sr concentrations in fish collected downstream and upstream (background) of LANL, however, were very small. Based on the average concentrations (±2SD) of radionuclides in fish tissue from the four LANL confluences, the committed effective dose equivalent from the ingestion of 46 lb (21 kg) (maximum ingestion rate per person per year) of fish muscle plus bone, after the subtraction of background, was 0.1 ± 0.1 mrem y^‐1 (1.0 ± 1.0 μSv y^‐1), and was far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem y^‐1 (1000 μSv y^‐1). Of the trace elements that were found above the limits of detection (Ba, Cu, and Hg) in fish muscle collected from the confluences of canyons that cross LANL and the RG, none were in significantly higher (p<0.05) concentrations than in muscle of fish collected from background locations.     

Radionuclides in deer and elk from Los Alamos national laboratory and the doses to humans from the ingestion of muscle and bone

Abstract

This paper summarizes radionuclide concentrations (³H, ⁹⁰Sr, ¹³⁷Cs, ²³⁸Pu, ^239,240Pu, ²⁴¹Am, and ^totU) in muscle and bone tissue of mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus) collected from Los Alamos National Laboratory (LANL), Los Alamos, New Mexico, lands from 1991 through 1998. Also, the committed effective dose equivalent (CEDE) and the risk of excess cancer fatalities (RECF) to people who ingest muscle and bone from deer and elk collected from LANL lands were estimated. Most radionuclide concentrations in muscle and bone from individual deer (n = 11) and elk (n = 22) collected from LANL lands were either at less than detectable quantities (where the analytical result was smaller than two counting uncertainties) and/or within upper (95%) level background (BG) concentrations. As a group, most radionuclides in muscle and bone of deer and elk from LANL lands were not significantly higher (p<0.10) than in similar tissues from deer (n = 3) and elk (n = 7) collected from BG locations. Also, elk that had been radio collared and tracked for two years and spent an average time of 50% on LANL lands were not significantly different in most radionuclides from road kill elk that have been collected as part of the environmental surveillance program. Overall, the upper (95%) level net CEDEs (the CEDE plus two sigma for each radioisotope minus background) at the most conservative ingestion rate (50 lbs of muscle and 13 lbs of bone) were as follows: deer muscle = 0.22 mrem y^‐1 (2.2 μSv y^‐1), deer bone = 3.8 mrem y^‐1 (38 μSv y^‐1), elk muscle = 0.12 mrem y^‐1 (1.2 μSv y^‐1), and elk bone = 1.7 mrem y^‐1 (17 μSv y^‐1). All CEDEs were far below the International Commission on Radiological Protection guideline of 100 mrem y^‐1 (1000 μSv y^‐1), and the highest muscle plus bone net CEDE corresponded to a RECF of 2E‐06, which is far below the Environmental Protection Agency upper level guideline of 1E‐04.