bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhalation toxicology: Starting with the environment
Authors: Dorough H. Wyman 
Published: March 2010

Abstract
The theme of SETAC's Second Annual Meeting was Environmental Risk Assessment, with emphasis on the use of data in the risk assessment and overall decision making process for chemicals. Needs for specific types of data were emphasized by the theme of the meeting and in no area was the void more obvious than in inhalation toxicology. Sufficient information for decision making in this area simply is not available, and no better combination of expertise exists for making judgments of risk than that of the environmental and mammalian toxicologists. To foster further communication between the two, a symposium was held in which experienced mammalian-oriented toxicologists were asked to address the state-of-the-art of inhalation toxicology for the benefit of those more oriented toward the traditional environmental toxicology area. Papers for the symposium are published herein to encourage continued efforts by all toxicologists to share in the data development and decision making process essential for healthy humans to enjoy a quality environment. The present paper is introductory in nature but utilizes recent findings in the author's laboratory concerning inhalation exposure and retention of chemical vapors in rats to demonstrate the rationale for selecting other topics for presentation.
Organizing data for environmental studies
Authors: Neely W. Brock 
Published: March 2010

Abstract
Using the vapor pressure, water solubility and molecular weight of a chemical, the partitioning of that chemical between the major environmental compartments can be quickly assessed. Thus it is possible to estimate what percentage of the chemical will be located in the ground, bottom sediments, water and air. Combining this information with a knowledge of the known degradation rates an estimation of the relative persistence of the chemical can be made. The technique is illustrated by ranking 84 of the 119 priority pollutants according to their potentials for contaminating water. A final example demonstrates how the model may be used to identify the potential environmental impact of a new chemical.
Pesticides in agricultural runoff and their effects on downstream water quality
Authors: Willis Guye H. , McDowell Leslie L. 
Published: March 2010

Abstract
Agricultural use of pesticides has remained high for economic reasons. Because aquatic species may bioaccumulate pesticides more readily than terrestrial organisms, there has been much concern about pesticides in agricultural runoff. Despite this concern, there presently is little relevant information for use in making accurate predictions of the impact of specific pesticide amounts in agricultural runoff on water quality at some point downstream. There is a compelling need for fundamental research on the physical, chemical, biological and hydrological processes that regulate pesticide behavior not only in agricultural and aquatic habitats, but also during transit between the two. Further, data are needed concerning pesticide toxicity potential as a function of the aquatic physical and chemical regime, and concerning population recovery dynamics as a function of pesticide concentration and species stress.
Fate of lindane in the aquatic environment: Rate constants of physical and chemical processes
Authors: Saleh Farida Y. , Dickson Kenneth L. , Rodgers John H. 
Published: March 2010

Abstract
Water solubility, hydrolysis and photolysis rate constants, and sorption-desorption partition coefficients were determined for lindane in three different natural water-sediment systems, as well as in a Milli-Q water and montmorillonite clay system. The aqueous solubility of lindane in surface waters at 25 ± 1°C ranged from 7.9 to 8.4 mg/L. In Milli-Q water, lindane solubility was 9.2 mg/L. At α = 0.05, no significant difference was found between the values in different natural waters; however, the Milli-Q water solubility did differ statistically. Lindane hydrolysis was found to be catalyzed by hydroxide and hydrogen ions. Neutral hydrolysis was relatively unimportant. Hydrolysis data followed first-order kinetics with kh values of 74 × 10−4 h−1 at pH 9 and 7.4 × 10−1 h−1 at pH 5. Experimental hydrolysis half-life (t1/2) in natural waters of pH 9.3 was comparable to the calculated value (92 h). Other natural water systems of pH 7.3 and 7.8 had t1/2 values greater than calculated values. Adjusted mid-winter photolysis half-life of lindane in Milli-Q water was 1.56 × 103 h. Photolysis rate enhancement was noted in natural water of pH 9.3, possibly due to the alkaline hydrolysis side reaction. Photolysis rate retardation was noted in natural water of pH 7.3 and 7.8. Sorption-desorption coefficient in Milli-Q water-montmorillonite clay was 1,259. Sorption coefficients for the natural systems ranged from 56 to 2,238. Results of the sorption-desorption experiments indicate that the wide diversity of the characteristics of the natural water sediment systems considerably affect the lindane sorption-desorption behavior.
The absence of hepatic cellular anomalies in TCDD-exposed beach mice — a field study
Authors: Cockerham Lorris G. , Young Alvin L. 
Published: March 2010

AbstractQuantitative ultrastructural studies were conducted on liver tissue from beach mice, Peromyscus polionotus, exposed to the toxin 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in a field environment. Hepatic tissue from 30 animals was examined for changes in smooth endoplasmic reticulum, rough endoplasmic reticulum and mitochondria. Fifteen animals were collected from a unique military test site in northwest Florida, where they had been continuously exposed to soil levels of &lt; 10 to 710 parts per trillion (ppt) TCDD. The remaining animals were from a control field not exposed to TCDD. All tissue was examined both histopathologically and by an ultrastructural stereological technique.The mean levels of TCDD in composite liver samples from exposed mice collected in the field varied from 960 ppt for females to 1,300 ppt for males. The levels of TCDD in the livers of the beach mice collected from the field substantiated the bioaccumulation of TCDD. Although the levels of TCDD in the livers were greater than those found in the soil, TCDD was not detected in the portion of the food chain consisting of seeds.No significant histopathological or ultrastructural changes were found in hepatic parenchymal cells after long-term, low-level exposure to TCDD in the field. The levels of TCDD encountered in this study, though much lower than those normally found in most laboratory experiments, are far greater than the estimated concentrations in the environment, or in animal tissues after normal application of the herbicide 2,4,5-T.
Alternative models for describing the bioconcentration of organics in fish
Authors: Spacie Anne , Hamelink Jerry L. 
Published: March 2010

Abstract
The accumulation of organic residues in fish is the result of competing rates of uptake and elimination, which can be modeled by pharmacokinetic techniques. Although first-order kinetics are usually assumed, they are rarely verified. Models with biphasic, second-order or Michaelis-Menten kinetics may prove to be better choices, depending on exposure level and mode of elimination. The well-known correlation between bioconcentration factor and partition coefficient (P) derives from separate correlations for the uptake and elimination rate constants with P. While such correlations appear to be linear in the range of log P = 2–5 for organics that are not metabolized, they sometimes fail at higher values of log P. A drug transport model is proposed to account for the “non-ideal” bioconcentration of a variety of organics in fish. According to this model, uptake is a nonlinear function of partition coefficient, water solubility and membrane permeability.
Environmental safety assessment of dipropylene glycol dibenzoate
Authors: Butz Robert G. , Atallah Yousef H. , Yu Ching C. , Calo Charles J. 
Published: March 2010

Abstract
Dipropylene glycol dibenzoate (Benzoflex® 9–88) (C20H22O5) is a primary plasticizer. It has a low order of toxicity, is biodegradable and is rapidly eliminated by mammals. The effect of Benzoflex 9–88 on microbial functions was mixed (cellulose degradation, urea degradation and sulfate reduction). Its octanol-water partition coefficient is 455 ± 15. It was not mutagenic in the Ames test and the Saccharomyces test.
Acute and chronic effects of diflubenzuron (Dimilin) on freshwater fish and invertebrates
Authors: Nebeker Alan V. , McKinney Phillip , Cairns Michael A. 
Published: March 2010

Abstract
Two fish and seven invertebrate freshwater species were exposed to diflubenzuron (Dimilin®) in acute and chronic laboratory tests. No effects on newly hatched and juvenile fathead minnows or juvenile guppies were seen at or below 36 μg/L, the highest concentration tested. An early-life-stage test (30-d) with fathead minnows showed no effect at or below 36 μg/L. No effects on survival, growth or reproduction were observed with two snail species, Juga plicifera and Physa spp., at or below 36 μg/L. Adult emergence of the caddis fly Clistoronia magnifica was inhibited at 0.1 μg/L. Daphnia magna were killed at 2.0 μg/L. Hyalella azteca mortality was significant at 2.0 μg/L. Molting and survival of the midge Tanytarsus dissimilis were affected at 4.9 μg/L. Molting and survival of the midge Cricotopus spp. were affected at 4.9 μg/L, and adult emergence did not occur at 1.6 μg/L.
Ultrastructural changes in the hepatocytes of juvenile rainbow trout and mature brown trout exposed to copper or zinc
Authors: Leland Harry V. 
Published: March 2010

Abstract
Morphological changes in hepatocytes of mature brown trout (Salmo trutta Linnaeus) and juvenile rainbow trout (Salmo gairdneri Richardson), accompanying chronic exposures to copper and zinc, were examined by transmission electron microscopy. At a concentration of copper not inhibitory to the final stages of gonadal development or spawning of brown trout, structural alterations included contraction of mitochondria and a tendency for nuclei to be slightly enlarged. Concentrations of copper or zinc lethal to a small fraction (10% and 4%, respectively) of a population of juvenile rainbow trout exposed for 42 d during larval and early juvenile development caused hepatocyte changes in survivors indicative of a reduction in ability to maintain intracellular water and cation balance and possible intranuclear metal sequestering. Specific structural alterations included increased vesiculation of rough endoplasmic reticulum, an increase in the abundance of electron-dense particles in the nucleus, increases in the numbers of multilaminar and globular inclusions, pooling of glycogen, increased autophagocytic activity and an increase in the number of necrotic cells. At advanced stages of toxicosis (concentrations of copper or zinc lethal to approximately 50% of the juveniles exposed for 42 d during development), loss in integrity of mitochondrial membranes, rupturing of plasma and nuclear membranes, separation of granular and fibrillar nuclear components, fragmentation of endoplasmic reticulum, and extensive autophagic vacuolization were significant features of hepatocytes of surviving juvenile rainbow trout.
The mussel watch: Intercomparison of trace level constituent determinations
Authors: Galloway Walter B. , Lake James L. , Phelps Donald K. , Rogerson Peter F. , Bowen Vaughan T. , Farrington John W. , Goldberg Edward D. , Laseter John L. , Lawler George C. , Martin John H. , Risebrough Robert W. 
Published: March 2010

Abstract
The U.S. National Mussel Watch Program initially used split-sample analyses for interlaboratory quality control purposes. These indicated the possibility of interlaboratory analytical discrepancies as well as problems in the split-sample technique itself. For the third year of the program, two mussel homogenates were produced to serve as intercomparison samples — one for metals and organics, the other for radionuclides. The results obtained using these homogenates are encouraging in that generally good agreement is seen among analyses done by several labs in diverse pollutant classes. We conclude from this experience that a quality-control program relying on the analysis of large homogeneous samples of the matrix being dealt with is an essential part of any extensive, multilaboratory analytical program.
Monitoring aldicarb residues in Florida soil and water
Authors: Jones R. L. , Back R. C. 
Published: March 2010

Abstract
Soil and water monitoring studies have been conducted to characterize the movement of aldicarb residues in Florida citrus groves. Samples were taken in 1980 and 1981 from TEMIK-treated groves on six farms located in five counties. In the soil, aldicarb residues decay rapidly to relatively nontoxic compounds. No significant concentrations of aldicarb were found in potable wells or in surface water around the six sampling sites. The monitoring results have been compared with the predictions of the Environmental Protection Agency computer model PESTAN. These calculations indicate that only a small fraction (&lt; 1%) of the aldicarb applied to a Florida citrus grove during the spring flush (the required application period) would normally reach shallow groundwater. The monitoring data and model calculations demonstrate that the use of TEMIK in Florida citrus groves will not result in persistent aldicarb residues in Florida groundwater.
Evaluation of a static renewal chronic toxicity test method for Daphnia magna straus using boric acid
Authors: Gersich Francis M. 
Published: March 2010

Abstract
A procedure for conducting chronic daphnid static renewal tests has been developed and evaluated, using boric acid as the test material. This procedure is an improvement over other proposed procedures for the following reasons: (a) the test methodology and equipment simplify the operations required to perform the test, (b) data on all endpoints for a particular concentration are obtained from the same group of test organisms and (c) the experimental design permits statistical interpretation of the critical endpoints. The acute and chronic effects of boric acid on Daphnia magna were similar to those reported in the literature. The 48-h static acute LC50 value (and 95% confidence intervals) for boric acid were 133 (115–153) mg/L as boron. The chronic toxicity of boric acid estimated by derivation of the maximum acceptable toxicant concentration was between 6.4 and 13.6 mg/L as boron.
Evaluation of the potential hazard to barn owls of talon (brodifacoum bait) used to control rats and house mice
Authors: Hegdal Paul L. , Blaskiewicz Raymond W. 
Published: March 2010

Abstract
During 1980, a radiotelemetry study on barn owls (Tyto alba) was conducted to evaluate the secondary hazards of the anticoagulant rodenticide TALON® (containing 0.005% brodifacoum) when it was used for controlling rats (Rattus spp.) and house mice (Mus musculus) on farms. Thirty-five active nests were located in about 1,100 km2 (430 mi2) in southwestern New Jersey. Starting on June 9, 1980, radio transmitters with tail clips were attached to 26 adult nesting barn owls and 8 fledged young of the year. In one 20-km2 (about 8 mi2) area, which was the most intensively searched, 12 active barn owl nests were located. Of all 35 active nests, 66% were in trees, 11% in barns, 8.5% in silos, 8.5% in chimneys and 6% in miscellaneous locations. Analysis of regurgitated pellets showed that meadow voles (Microtus pennsylvanicus) were the most common prey at all sites. Although Norway rats (Rattus norvegicus) and house mice occurred in some pellet collections, they made up only a small part of the diet (3.9% rats and 2% mice) of barn owls in the study area. Baiting at farms with TALON was begun on July 24, and ended on September 29, 1980. TALON was not observed to cause or implicated in barn owl mortality during the study. However, trace residues (&lt; 0.05 ppm, the limit of determination) of brodifacoum were found in one electrocuted barn owl. Young barn owls were fledged from at least eight sites where poisoned rodents were available on the farms for at least part of the nesting and feeding period (including pre- and postfledging). Furthermore, radiotelemetry confirmed that at least 9, and possibly 12, of the radio-equipped owls were present on sites posttreatment, when census evaluations showed commensal rodents were present and consuming TALON bait.
Absence of mutagenic activity of sodium borate (borax) and boric acid in the Salmonella preincubation test
Authors: Benson William H. , Birge Wesley J. , Dorough H. Wyman 
Published: March 2010

Abstract
The mutagenicity of borax and boric acid was examined in Salmonella typhimurium strains TA98 and TA100 by the preincubation method. No mutagenic activity of borax or boric acid was observed with or without S-9 rat liver enzymes. Experiments also were conducted to investigate the enhancement or inhibition of benzo[a]pyrene (B[a]P) mutagenicity by the two compounds. Neither Borax nor boric acid had any effect on the response of S. typhimurium test strains to B[a]P. Studies conducted to determine the influence of exposure to sunlight for 8 h on the mutagenicity of these materials showed that the nonmutagenic activity of borax or boric acid was not altered, but that the mutagenicity of B[a]P was reduced by approximately one-half. Photodecomposition may be an important factor in rendering this polycyclic aromatic hydrocarbon nonmutagenic under environmental conditions.
Effects of cadmium on the population growth of a benthic invertebrate Aeolosoma Headleyi (oligochaeta)
Authors: Niederlehner B. R. , Buikema A. L. , Pittinger C. A. , Cairns J. 
Published: March 2010

Abstract
A chronic toxicity test using population growth of an aquatic oligochaete, Aeolosoma headleyi, was evaluated for usefulness in determining the hazard of chronic exposures to cadmium. Tests were conducted in artificial hard water (180 mg/L hardness) and dechlorinated tap water (60 mg/L hardness). After 10 to 14 d of exposure, there were significant differences between groups in population growth rate or number of worms in both water types. The no-observable-effects concentrations (NOEC) for replicate tests in artificial hard water were 32.0 and 53.6 μg/L cadmium. The 48-h LC50 in artificial hard water was 4,980 μg/L, yielding acute/chronic ratios of 155 and 92, respectively. The oligochaete was more sensitive in the softer dechlorinated tap water, with a NOEC of 17.2 μg/L cadmium and a 48-h LC50 of 1,200 μg/L. The acute/chronic ratio was 70. Dose-response curves were linear at higher concentrations, but stimulation of reproduction was noted at low concentrations. A. headleyi was comparable in sensitivity to other organisms tested, as cited by the U.S. Environmental Protection Agency criterion document, in acute exposures but less sensitive in chronic exposures. The test proved to be short and simple, and provided useful data on an animal with a life history distinctly different from that of the most commonly tested aquatic invertebrate, Daphnia.
Toxicity of cadmium in water and sediment slurries to Daphnia Magna
Authors: Nelson Peter O. , Ratcliff Alan K. , Schuytema Gerald S. , Malueg Kenneth W. , Nebeker Alan V. , Krawczyk Daniel F. , Gakstatter Jack H. 
Published: March 2010

Abstract
Daphnia magna Straus were exposed to cadmium for 48 h in water and in equilibrated water-sediment slurries using beakers and recirculating test chambers. Differences in toxicity based on dissolved and free cadmium (Cd2+) between the two levels of tested total solids, 100 and 1000 mg/L, were not significant (α = 0.05). The mean water LC50 of 39 μg/L total cadmium was significantly (α = 0.05) lower than the mean LC50 of 91 μg/L dissolved cadmium in the slurries, indicating that cadmium adsorbed to the sediment had negligible toxicity. Low LC50 values in two sediment bioassays correspond with low pH's. Adsorption isotherms using cadmium, well water, and freshwater sediment were developed for sediment concentrations approximating those at which the bioassays were performed. Conditional adsorption constants derived from the isotherms predicted the distribution of cadmium between well water and sediments. A speciation model predicted that organic ligands released from the sediments strongly complexed the free cadmium ion. Based on free cadmium ion concentrations, no significant differences (α = 0.05) could be detected between the mean of the slurry bioassay LC50 (47 μg/L) and aqueous bioassay LC50 (30 μg/L). Speciation results, LC50 values based on free cadmium ion concentrations only, and pH results gave indirect evidence that the free cadmium ion was the predominant toxic species to D. magna in the bioassays.
Surveillance of phthalate esters in surface waters and sediments in the United States
Authors: Michael Paul R. , Adams William J. , Werner A. Frances , Hicks Orville 
Published: March 2010

Abstract
Four phthalate ester products (three alkyl benzyl and one dialkyl phthalate) were monitored in industrial areas of the United States over 3 years (1980–1982). Documented methodology and quality assurance practices for both sample collection and analysis assured validity of results. The geometric mean concentration (corrected for method losses) for the three benzyl phthalates was less than 0.6 μg/L in surface waters and less than 0.2 μg/g in sediments. Only 20 of 205 water samples (10%) and 13 of 122 sediment samples (11%) had detectable levels of one of the benzyl phthalates. The geometric mean concentration (corrected for method losses) for C7,9,11 dialkyl phthalate was less than 3 μg/L in surface waters and less than 0.6 μg/g in sediments. Only 13 of 138 water samples (9%) and 1 of 90 sediment samples (1%) had detectable levels of C7,9,11 dialkyl phthalate.
Effects of chronic exposure to coal-derived oil on freshwater ecosystems: II. Experimental ponds
Authors: Giddings Jeffrey M. , Franco Paul J. , Cushman Robert M. , Hook Leslie A. , Southworth George R. , Stewart Arthur J. 
Published: March 2010

Abstract
Ten 15-m3 outdoor ponds were treated daily for 8 weeks with a synthetic coal-derived crude oil; ecological effects were monitored for an additional 52 weeks. The experimental design included two replicate ponds at each of five oil input rates (from 1 to 16 ml/m3/d) plus two untreated controls. A gradient of responses was observed across the gradient of treatment levels. Cladoceran zooplankton populations and ecosystem metabolism (production/respiration) were affected at the lowest input rate, but the effects disappeared before the end of the oiling period and this exposure level (approximately 3% of the 48-h LC50 for Daphnia magna) was considered safe for this ecosystem. At the next higher treatment level, effects on zooplankton and ecosystem metabolism were greater and persisted until the oiling ended; reproduction of mosquitofish (Gambusia affmis) was also impaired. Major changes occurred throughout the ecosystem at higher treatment levels. The two highest treatment levels completely disrupted the pond community: The ponds recovered from the next-to-highest treatment but the effects of the highest treatment persisted for more than a year. Indirect effects occurred at all treatment levels and included changes in water quality, replacement of sensitive taxa by more tolerant competitors and changes in abundance of some species because of increases or decreases in their predators. The results of this experiment were qualitatively and quantitatively similar to those of a parallel experiment in pond-derived microcosms, and thus substantiated the ability of the microcosms to simulate larger, more natural ecosystems.