bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling impact of parathion and its metabolite paraoxon on the nematode Caenorhabditis etegans in soil
Authors: Saffih-Hdadi Kawtar , Bruckler Laurent , Amichot Marcel , Belzunces Luc 
Published: May 2005

Abstract
Parathion is an insecticide of a group of highly toxic organophosphorous compounds. In vivo, it is activated to the toxic metabolite paraoxon. Laboratory experiments have shown that a single relationship between the variable (concentration × time of application) and the percentage of paralyzed nematodes is relevant. Aqueous (0.01 M CaCl2) extracts from soil that had received a dose of parathion as used in practice during an incubation experiment had no effect on nematodes, because sorption and biodegradation of the pesticide decreased the pesticide concentration in the soluble phase. To predict the toxicological effects of parathion and paraoxon on nematodes under various soil conditions during a simulation period of 20 d, we used a model predicting the concentrations of parathion and paraoxon over time in the soil liquid phase. In this model, sorption and biodegradation of both parathion and paraoxon were taken into account, and the results indicated that sorption effects were dominant and determined the differential toxicological risks between soils. Variable effects were predicted for short times (typically &lt;5 d), and critical toxicological conditions were predicted for longer duration (typically &gt; 10–15 d), in all cases.
Influence of larval period on responses of overwintering green frog (Rana clamitans) larvae exposed to contaminated sediments
Authors: Snodgrass Joel W. , Hopkins William A. , Jackson Brian P. , Baionno Jennifer A. , Broughton Jeffroy 
Published: May 2005

Abstract
Pond-breeding amphibians exhibit large intra- and interspecific differences in the duration of the aquatic larval phase. In contaminated aquatic environments, a prolonged larval phase means prolonged exposure to pollutants and, potentially, more severe toxic effects. In the laboratory, we tested this hypothesis by exposing green frog larvae (Rana clamitans) to commercial clean sand (control), sediment from an abandoned surface mine (mine), or sediment contaminated with coal combustion waste (CCW). By collecting eggs late in the breeding season, we obligated larvae to overwinter and spend a protracted amount of time exposed to contaminated sediments. The experiment was continued until all larvae either successfully completed metamorphosis or died (301 d). Larvae exposed to mine sediments accumulated significant levels of Pb and Zn, whereas larvae exposed to CCW-contaminated sediment accumulated significant levels of As, Se, Sr, and V. Larvae exposed to mine sediments suffered sublethal effects in the form of reduced growth and size at metamorphosis, but the proportion of larvae successfully completing metamorphosis (93%) was the same for both control and mine treatments. In contrast, larvae exposed to CCW-contaminated sediment suffered greatly reduced survival (13%) compared to both control and mine treatments. Moreover, among larvae in the CCW treatment, the majority of mortality occurred during the latter part the overwintering period (after day 205), corresponding to the onset of metamorphosis in the controls. Our results suggest that the length of the larval period may be one of many life-history or ecological characteristics that influence the sensitivity of aquatic breeding amphibians to environmental pollutants.
Arsenic and mercury tolerance and cadmium sensitivity in Arabidopsis plants expressing bacterial γ-glutamylcysteine synthetase
Authors: Li Yujing , Dhankher Om Parkash , Carreira Laura , Balish Rebecca S. , Meagher Richard B. 
Published: May 2005

Abstract
Cysteine sulfhydryl-rich peptide thiols are believed to play important roles in the detoxification of many heavy metals and metalloids such as arsenic, mercury, and cadmium in plants. The γ-glutamylcysteine synthetase (γ-ECS) catalyzes the synthesis of the dipeptidethiol γ-glu-cys (γ-EC), the first step in the biosynthesis of phytochelatins (PCs). Arabidopsis thaliana, engineered to express the bacterial γ-ECS gene under control of a strong constitutive actin regulatory sequence (A2), expressed γ-ECS at levels approaching 0.1% of total protein. In response to arsenic, mercury, and cadmium stresses, the levels of γ-EC and its derivatives, glutathione (GSH) and PCs, were increased in the A2::ECS transgenic plants to three- to 20-fold higher concentrations than the increases that occurred in wild-type (WT). Compared to cadmium and mercury treatments, arsenic treatment most significantly increased levels of γ-EC and PCs in both the A2::ECS transgenic and WT plants. The A2::ECS transgenic plants were highly resistant to arsenic and weakly resistant to mercury. Although exposure to cadmium produced three- to fivefold increases in levels of γ-EC-related peptides in the A2::ECS lines, these plants were significantly more sensitive to Cd(II) than WT and trace levels of Cd(II) blocked resistance to arsenic and mercury. A few possible mechanisms for γ-ECS-enhanced arsenic and mercury resistance and cadmium hypersensitivity are discussed.
Induction of ethoxy-resorufin-O-deethylase activity by halogenated aromatic hydrocarbons and polycyclic aromatic hydrocarbons in primary hepatocytes of the green frog (Rana esculenta)
Authors: Rankouhi Tanja Rouhani , Koomen Bas , Sanderson J. Thomas , Bosveld Albertus T.C. , Seinen Willem , van den Berg Martin 
Published: May 2005

Abstract
In this study, we measured the ethoxy-resorufin-O-deethylase (EROD) activity in primary hepatocytes of the common green frog Rana esculenta as a biomarker for cytochrome P4501A induction. We exposed hepatocytes derived from male and female frogs to several halogenated aromatic hydrocarbons, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachlorodibenzofuran (PCDF), polychlorinated biphenyls (PCB-126, PCB-118), and polycyclic aromatic hydrocarbons such as benzo[a]pyrene (BaP), chrysene, anthracene, and pyrene. Exposure to PCB-118, anthracene, and pyrene, up to 1 μM, did not induce EROD activity, whereas TCDD and PCDF induced EROD activity maximally. In our primary frog hepatocytes, exposure to chrysene and BaP resulted in median effective concentration values (EC50) in the high nM range (82–1035 nM). Exposure to TCDD, PCDF, and PCB-126 resulted in EC50 values of 0.4 to 8, 0.07 to 0.7, and 3 to 133 nM, respectively, which is in the same range as EC50 values found in primary hepatocytes of birds. Compared to our frog hepatocytes, primary rat hepatocytes seem to be more sensitive to TCDD, chrysene, and BaP.
Stress synergy between environmentally realistic levels of copper and frost in the earthworm Dendrobaena octaedra
Authors: Bindesbøl Anne-Mette , Holmstrup Martin , Damgaard Christian , Bayley Mark 
Published: May 2005

Abstract
In their natural habitat, animals are exposed to a variety of stress factors, including extreme temperatures, low water availability, and toxic stress from chemical pollutants. In this study we examined the interaction between realistic environmental levels of soil-copper contamination and realistic winter temperatures on survival of the cosmopolitan freeze-tolerant earthworm Dendrobaena octaedra. These interactions were tested using a full factorial design with six copper concentrations between 0 and 200 mg Cu/kg dry soil and five temperatures from +2 to −8°C. A highly significant synergistic interaction existed that demonstrates that exposure to subzero temperatures significantly reduced copper tolerance and, conversely, that copper exposure significantly reduced freeze tolerance. Copper had no effect on glucose production, which is believed to be a major component of the cryoprotective system and the only known cryoprotectant in D. octaedra. This points to other mechanisms behind the observed synergy, possibly impaired osmoregulatory function of the cell membrane. The results support the working hypothesis that interactions between toxicants and dominant natural stress factors can alter the organisms' tolerance to these individual stressors.
Endocrine (sexual) disruption is not a prominent feature in the pike (Esox lucius), a top predator, living in english waters
Authors: Vine Emma , Shears Jan , van Aerle Ronny , Tyler Charles R. , Sumpter John P. 
Published: May 2005

Abstract
The high incidence of intersex roach (Rutilus rutilus) in some United Kingdom rivers that has been associated with exposure to sewage treatment works (STWs) effluent led us to hypothesize that top predator fish also may be affected by estrogenic chemicals, because they are likely to bioaccumulate lipophilic compounds through a predator-prey relationship. To investigate this possibility, pike (Esox lucius) were sampled both upstream and downstream of STWs and then examined for total estrogenic activity of their bile, as measured using a yeast-based estrogen assay to determine the degree of recent exposure of the pike to estrogens and vitellogenin induction, and for possible disruption of sexual development, as measured using histological analysis of the gonads. No evidence of severe disruption was found in the sampled fish, which came from 16 sampling sites that were representative of English rivers. However, 14% of pike were intersex, of which 15 of 16 showed patches of male germ cells among predominantly female gonadal tissue. The incidence of masculinization was independent of whether the pike had been sampled upstream or downstream of STWs. Although pike are gonochoristic, it is not known if this masculinization of presumptive female pike is normal or, instead, indicative of endocrine disruption. Vitellogenin concentrations were not elevated in male pike at sites either upstream or downstream of STWs. The results suggest that sexual disruption is not common in pike, a fish at the top of the food chain in the freshwaters of England.
Calculating life-cycle assessment effect factors from potentially affected fraction-based ecotoxicological response functions
Authors: van de Meent Dik , Huijbregts Mark A.J. 
Published: May 2005

Abstract
A new multisubstance potentially affected fraction (msPAF)-based method for calculating ecotoxicological effect factors for life-cycle assessment is introduced and compared to two other available methods of calculation. The new method is based on marginal increase of the msPAF of species. The method follows concentration-additive rules for pollutants with the same toxic mode of action (TMoA) and response-additive calculation rules for pollutants with independent action, and it combines a TMoA-specific factor, which is calculated differently in different methods, and a substance-specific factor, which is common to all methods. For 261 substances in 22 toxic modes of action, ecotoxicological effect factors for freshwater ecosystems have been calculated by different methods. Method-related differences appear to be rather small. Intersubstance differences in effect factors stem from differences in substance-specific toxic potencies, which span eight orders of magnitude, rather than from differences in TMoA-specific factors, which span only three orders of magnitude. Based on these insights, the choice of a calculation method seems to be a matter of personal (scientific) preference. The new hybrid msPAF method was greatly sensitive to data that usually are not known with sufficient certainty. Its use is recommended, entirely for reasons of scientific consistency, under strict conditions. When such conditions are not met or if necessary parameter values are unavailable, use of a fixed value for the TMoA-specific component is recommended.
Origins of the WHO Framework Convention on Tobacco Control
Authors: Roemer Ruth , Taylor Allyn , Lariviere Jean 
Published: May 2005

The World Health Organization (WHO) Framework Convention on Tobacco Control originated in 1993 with a decision by Ruth Roemer and Allyn Taylor to apply to tobacco control Taylor’s idea that the WHO should utilize its constitutional authority to develop international conventions to advance global health. In 1995, Taylor and Ruth Roemer proposed various options to WHO, recommending the framework convention-protocol approach conceptualized by Taylor. Despite initial resistance by some WHO officials, this approach gained wide acceptance. In 1996, the World Health Assembly voted to proceed with its development. Negotiations by WHO member states led the World Health Assembly in May 2003 to adopt by consensus the WHO Framework Convention on Tobacco Control—the first international treaty adopted under WHO auspices. The treaty formally entered into force for state parties on February 27, 2005.
The Role of Training in Global Tobacco Control Research
Authors: Kassel Jon D. , Ross Hana 
Published: May 2005

Despite the pandemic nature of the tobacco control problem, little attention has been given to the role of research training in stemming the global tide of tobacco use. Tobacco research plays a critical role in both shaping policy and saving lives, and training new tobacco researchers is an important part of the tobacco control agenda. There are several conceptual training models, all of which emphasize communicative partnerships and multidisciplinary approaches. It also is important to take cultural background and specificity into account when shaping research and training agendas. We present a number of successful training initiatives and address both the strengths and the pitfalls of these endeavors.
The Landscape in Global Tobacco Control Research: A Guide to Gaining a Foothold
Authors: Lando Harry A. , Borrelli Belinda , Klein Laura C. , Waverley Linda P. , Stillman Frances A. , Kassel Jon D. , Warner Kenneth E. 
Published: May 2005

Smoking prevalence is shifting from more- to less-developed countries. In higher-income countries, smoking surveillance data, tailored treatments, public health campaigns, and research-based policy implementation have led to a decrease in tobacco use. In low- and middle-income countries, translating research into practice and policy is integral for tobacco control. We describe the landscape of existing resources, both financial and structural, to support global tobacco control research and strengthen research capacity in developing countries. We identify key organizations that support international efforts, provide examples of partnerships between developed and developing countries, and make recommendations for advancing global tobacco research. There is a need for increased commitment from organizations to support global tobacco control research.
A Longitudinal Assessment of the Impact of Smoke-Free Worksite Policies on Tobacco Use
Authors: Bauer Joseph E. , Hyland Andrew , Li Qiang , Steger Craig , Cummings K. Michael 
Published: May 2005

Objectives. In this cohort study, we assessed the impact of smoke-free work-site policies on smoking cessation behaviors. Methods. Smokers were tracked as part of the Community Intervention Trial for Smoking Cessation. Telephone surveys were administered to 1967 employed smokers in 1993 and 2001. Data were gathered on personal and demographic characteristics, tobacco use behaviors, and restrictiveness of worksite smoking policies. Results. People who worked in environments that changed to or maintained smoke-free policies between 1993 and 2001 were 1.9 times more likely (odds ratio [OR] = 1.92; 95% confidence interval [CI] = 1.11, 3.32) than people whose worksites did not do so to have stopped smoking by 2001. Continuing smokers decreased their average daily consumption by 2.57 cigarettes. People working in environments that had smoke-free policies in place in both 1993 and 2001 were 2.3 times more likely (OR=2.29; 95% CI=1.08, 4.45) than people not working in such environments to have quit by 2001, and continuing smokers reported a decline in average daily consumption of 3.85 cigarettes. Conclusions. Smoke-free worksite policies help employees reduce their cigarette consumption and stop smoking.
Tobacco Control Competencies for US Medical Students
Authors: Geller Alan C. , Zapka Jane , Brooks Katie R. , Dube Catherine , Powers Catherine A. , Rigotti Nancy , O’Donnell Joseph , Ockene Judith 
Published: May 2005

The 2004 National Action Plan for Tobacco Cessation recommended that the US Department of Health and Human Services convene a diverse group of experts to ensure that competency in tobacco dependence interventions be a core graduation requirement for all new physicians and other key health care professionals. Core competencies would guide the design of new modules and explicitly outline the learning objectives for all graduating medical students. In 2002, the National Cancer Institute funded a consortium to develop, test, and integrate tobacco curricula at 12 US medical schools. Because there was neither an explicit set of tobacco competencies for medical schools nor a process to develop them, one of the consortium’s tasks was to articulate competencies and learning objectives.
Simple Models for Phosphorus Loss from Manure during Rainfall
Authors: Gérard‐Marchant Pierre , Walter M. Todd , Steenhuis Tammo S. 
Published: May 2005

ABSTRACTMechanistic, predictive equations for phosphorus (P) transport in runoff from manure‐applied fields constitute a critical knowledge gap for developing nonpoint‐source pollution models. We derived two simple equations to describe the P release from animal manure during a rainfall event—one based on first‐order P desorption kinetics and one based on second‐order kinetics. The manure characteristics needed in the two kinetic equations are the maximum amount of water‐extractable phosphorus (WEP) and a characteristic desorption time. Water‐extractable P can be measured directly but currently the characteristic time can only be obtained by fitting experimental data. In addition, we evaluated two models usually used to estimate P loss from soil, the Elovitch equation and power function, both of which relate P loss to time. The models were tested against previously published data of P release from different manures under laboratory conditions. All equations fit the data well. Of the two kinetic equations, the second‐order model showed better agreement with the data than the first‐order model; for example, maximum relative differences between the model results and measured data were 2.6 and 4.7%, respectively. The characteristic times varied between 20 min for dairy manure and almost 100 min for poultry manure. The characteristic time did not appear to change with flow rate but decreased with smaller manure aggregates. The parameters for power‐function relationships could not be related to measured manure characteristics. These results provide the first step to process‐based approximations for predicting P release from manure with time during rainfall shortly after land application, when P losses are the greatest.
A Regional‐Scale Study on the Crop Uptake of Cadmium from Sandy Soils
Authors: Ingwersen Joachim , Streck Thilo 
Published: May 2005

ABSTRACTPlant uptake is one of the major pathways by which cadmium (Cd) in soils enters the human food chain. This study was conducted to investigate the uptake of Cd by crops from soils within the wastewater irrigation area (WIA) of Braunschweig (Germany) and to develop a simple process‐oriented model that is suited to predict Cd uptake at the regional scale. The sandy soils within the WIA (4300 ha) have received considerable loads of heavy metals by irrigation using municipal wastewater for up to 40 years. In 1998 and 1999, we sampled soil and plant material at 40 potato (Solanum tuberosum L.), 40 sugar beet (Beta vulgaris L.), and 32 winter wheat (Triticum aestivum L.) fields. In both years and for all three crops, we found close linear relationships between the Cd content of plant material and the Cd concentration in soil solution. For all three crops, we observed a trend of relatively increased Cd uptake in the year with the higher saturation deficit of the atmosphere. We interpret this to indicate that transpiration plays an important role in the Cd uptake of crops under the conditions of the WIA. In modeling the uptake of Cd by crops, we assume that uptake is proportional to mass flow, that is, the product of water transpired, Cd concentration in soil solution, and a plant‐specific empirical parameter. The simulations agreed well with the observed Cd contents in crops. Our model explained between 66 and 87% of the observed variance.
The Acetochlor Registration Partnership Surface Water Monitoring Program for Four Corn Herbicides
Authors: Hackett Amy G. , Gustafson David I. , Moran Sharon J. , Hendley Paul , van Wesenbeeck Ian , Simmons Nick D. , Klein Andrew J. , Kronenberg Joel M. , Fuhrman John D. , Honegger Joy L. , Hanzas John , Healy David , Stone Christopher T. 
Published: May 2005

ABSTRACTA surface drinking water monitoring program for four corn (Zea mays L.) herbicides was conducted during 1995–2001. Stratified random sampling was used to select 175 community water systems (CWSs) within a 12‐state area, with an emphasis on the most vulnerable sites, based on corn intensity and watershed size. Finished drinking water was monitored at all sites, and raw water was monitored at many sites using activated carbon, which was shown capable of removing herbicides and their degradates from drinking water. Samples were collected biweekly from mid‐March through the end of August, and twice during the off‐season. The analytical method had a detection limit of 0.05 μg L−1 for alachlor [2‐chloro‐N‐(2,6‐diethylphenyl)‐N‐(methoxymethyl)‐acetamide] and 0.03 μg L−1 for acetochlor [2‐chloro‐N‐(ethoxymethyl)‐N‐(2‐ethyl‐6‐methylphenyl)‐acetamide], atrazine [6‐chloro‐N‐ethyl‐N′‐(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine], and metolachlor [2‐chloro‐N‐(2‐ethyl‐6‐methylphenyl)‐N‐(2‐methoxy‐1‐methylethyl)‐acetamide]. Of the 16528 drinking water samples analyzed, acetochlor, alachlor, atrazine, and metolachlor were detected in 19, 7, 87, and 53% of the samples, respectively. During 1999–2001, samples were also analyzed for the presence of six major degradates of the chloroacetanilide herbicides, which were detected more frequently than their parent compounds, despite having higher detection limits of 0.1 to 0.2 μg L−1 Overall detection frequencies were correlated with product use and environmental fate characteristics. Reservoirs were particularly vulnerable to atrazine, which exceeded its 3 μg L−1 maximum contaminant level at 25 such sites during 1995–1999. Acetochlor annualized mean concentrations (AMCs) did not exceed its mitigation trigger (2 μg L−1) at any site, and comparisons of observed levels with standard measures of human and ecological hazards indicate that it poses no significant risk to human health or the environment.