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PubMed2005

Multi-species interactions impact the accumulation of weathered 2,2-bis (p-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE) from soil.

The impact of interactions between the earthworms Eisenia foetida and Lumbricus terrestris and the plants Cucurbita pepo and Cucurbita maxima on the uptake of weathered p,p'-DDE from soil was determined. Although some combinations of earthworm and plant species caused significant changes in the p,p'-DDE burden in both organisms, the effects were species specific. Contaminant bioconcentration in C. pepo was increased slightly by E. foetida and by 3-fold when the plant was grown with L. terrestris. E. foetida had no effect on the contaminant BCF by C. maxima, but L. terrestris caused a 2-fold reduction in p,p'-DDE uptake by the plant. Contaminant levels in E. foetida and L. terrestris were unaffected by C. pepo. When grown with C. maxima, the concentration of p,p'-DDE decreased by approximately 4-fold and 7-fold in E. foetida and L. terrestris, respectively. The data suggest that the prediction of contaminant bioavailability should consider interactions among species.

Animals↗
PubMed2006

Factors inhibiting bioremediation of soil contaminated with weathered oils and drill cuttings.

Oily drill cuttings and a soil contaminated with weathered crude oils were treated by enhanced biodegradation under tropical conditions in industrial scaled experiments. Oil contaminants were characterized by gas chromatography and mass spectrometry. This allowed for the identification of a mixture of two crude oils in the contaminated soil. After 12 months of bioremediation process, the removal of hydrocarbons reached by biodegradation an extent of 60% although nutrient amendment with elevated concentration of N-urea had highly detrimental effects on the hydrocarbon degrading fungal populations due to the production of toxic concentration of ammonia gas by nitrification. The saturated hydrocarbons were extensively assimilated, though n-alkanes were not completely removed. Aromatic hydrocarbons were less degraded than saturated whereas resin and asphaltene fractions were, surprisingly, partly assimilated. In laboratory conditions, the residual hydrocarbons in the field-treated materials were 15-20% further degraded when metabolic byproducts resulting from biodegradation were diluted or removed.

Biodegradation, Environmental↗
PubMed2005

The utility of geographic information systems (GIS) in rapid epidemiological assessments following weather-related disasters: methodological issues based on the Tropical Storm Allison Experience.

Flooding is the most common natural disaster worldwide, and is the leading cause of weather-related deaths in the United States. Tropical storm Allison hit landfall near Galveston, Texas on June 5, 2001, causing the most severe flood-related damage ever recorded in the Houston metropolitan area. This devastating storm dumped 37 in of rain in 24h on parts of the city, killing 22 people and causing more than $5 billion in damage. The main goal of the public health response to tropical storm Allison was to rapidly evaluate the immediate health needs of the community. Geographical information system (GIS) technology was instrumental to the timeliness of this effort. We conducted a rapid needs assessment in the areas most affected by flooding using modified cluster sampling facilitated by GIS methodology. Of the 420 households participating in the survey, we found a significant increase in illness (OR, 5.1; 95% CI, 2.7-9.4), injuries (OR, 4.8; 95% CI, 1.9-12.8), and immediate health needs (OR, 3.3; 95% CI, 1.7-6.1) among persons living in flooded homes compared to non-flooded homes. There were 60 households reporting serious damage, 24 of which were outside the 500-year flood plain. We also obtained reliable estimates of the extent of damage and household needs to help guide relief efforts. These findings underscore the usefulness of rapid needs assessment as a tool to identify actual health threats and to facilitate delivery of resources to those with the greatest and most immediate need. Our ability to swiftly plan and implement a rapid needs assessment over a large geographical region within 1 week following the damage would not have been possible without the utilization of GIS methodology and the availability of skilled personnel and timely data resources.

Disaster Planning↗
PubMed2006

Bioremediation and toxicity determination of natural seawater polluted with weathered crude oil by salt-tolerant consortia in a SBR.

The aim of this research was to compare the bioremediation treatment of seawater polluted with two different concentrations of weathered crude oil (0.2 for experiment (a) and 1.14% for experiment (b), v/v) by salt-tolerant consortia enriched from the sludge of a refinery wastewater treatment facility, in a SBR. The use of a commercial bioremediation stimulant (S200) was also evaluated as an alternative to the traditional nitrogen and phosphorus supplement.

Bacteria↗
PubMed2004

Reactive oxygen species scavenging ability of a new compound derived from weathered coal.

The scavenging activity of three fulvic acids (named XWCS-1, XWCS-4, and XWCS-8 according to time taken for ozonolysis) obtained by ozonolysis of humic acid extracted from Xinjiang (China) weathered coal and a fulvic acid (named XWCFA) extracted from the same coal towards reactive oxygen species such as superoxide radical (O(2)(.)(-)) and hydroxyl radical ((.)OH) was investigated with an electron spin resonance (ESR)-spin trapping method using 5,5-dimethyl-1-pyrroline N-oxide (DMPO) as a spin trap. O(2)(.)(-) was generated with a hypoxanthine-xanthine oxidase system. (.)OH was generated by three different methods; (i) FeSO(4)-hydrogen peroxide (H(2)O(2)) system, (ii) Cu(en)(2)-H(2)O(2) system, and (iii) UVB photolysis of H(2)O(2). At physiological pH, XWCS-1 had the greatest O(2)(.)(-) scavenging activity, followed by XWCS-4, XWCS-8 and XWCFA. XWCFA had the greatest ?OH scavenging activity among the four fulvic acids, whereas XWCS-1 and XWCS-4 enhanced the production of (.)OH from a metal-catalyzed hydroxyl radical generating system, suggesting that these molecules act as prooxidants in the presence of metal ion.

Benzopyrans↗
PubMed2006

Bioremediation of weathered-building stone surfaces.

Atmospheric pollution and weathering of stone surfaces in urban historic buildings frequently results in disfigurement or damage by salt crust formation (often gypsum), presenting opportunities for bioremediation using microorganisms. Conventional techniques for the removal of these salt crusts from stone have several disadvantages: they can cause colour changes; adversely affect the movement of salts within the stone structure; or remove excessive amounts of the original surface. Although microorganisms are commonly associated with detrimental effects to the integrity of stone structures, there is growing evidence that they can be used to treat this type of stone deterioration in objects of historical and cultural significance. In particular, the ability and potential of different microorganisms to either remove sulfate crusts or form sacrificial layers of calcite that consolidate mineral surfaces have been demonstrated. Current research suggests that bioremediation has the potential to offer an additional technology to conservators working to restore stone surfaces in heritage buildings.

Air Pollutants↗
PubMed2002

Differential bioavailability of field-weathered p,p'-DDE to plants of the Cucurbita and Cucumis genera.

Field experiments were conducted to assess the bioavailability of weathered p,p'-DDE in soil to plants in the Cucurbita (squash, pumpkin) and Cucumis (cucumber, melon) genera. As expected, significant variability exists in the uptake of p,p'-DDE between plants of different genera. Root:soil concentration factors, defined as the ratio of p,p'-DDE (ng/g, dry weight) in the roots to that in the soil, approach 1.8 for cucumbers/melons and 16 for squash/pumpkin. However, significant differences were also observed among varieties of squash and pumpkin, with greater than an order of magnitude variation in the root:soil concentration factors and up to two orders of magnitude difference in the absolute amount of contaminant present within the plant. Although root systems routinely contain the highest concentration of p,p'-DDE (ng/g), this compartment comprises less than 2% of the total plant biomass. In all varieties but one, more than 86% of the extracted pollutant was in the shoot system. For two of varieties of Cucurbita pepo, concentrations of p,p'-DDE in the stems reached 1.1-2.2 mg/g and estimations of percent contaminant extraction from the soil ranged from 0.40% to 2.4%. These values approach those observed in the phytoremediation of heavy metals by "hyperaccumulating" species and indicate the potential for a plant-based remediation approach to soils contaminated with persistent organic pollutants.

Biological Availability↗
PubMed1988

Influence of prepartum exposure of beef heifers to winter weather on concentrations of plasma energy-yielding substrates, serum hormones and birth weight of calves.

The influence of exposure to ambient winter weather conditions (WW) during the final 90 d of gestation on serum hormones, plasma substrates, and birth weight of calves was evaluated in spring-calving, primiparous beef heifers. At of 192+/-14 d of gestation, heifers were assigned by expected calving date, breed, and sire of fetus to one of two treatments. Thirteen heifers were assigned to thermoneutral environment (TN; 12 degrees C) and housed in temperature-controlled rooms. Heifers in WW (n=16) were maintained outdoors in drylots without access to shelter and given additional dietary energy when average weekly windchill fell below -6.7 degrees C. Body weights, hip-heights and samples of serum and plasma were obtained biweekly until heifers were relocated, approximately 7 d prior to expected calving. Polynomial response curves for concentrations of glucose and nonesterified fatty acids (NEFA) in plasma and cortisol in serum were not influenced by treatment. However, average concentrations of NEFA in plasma were increased (P<0.02) and glucose tended to be higher (P=0.13) in WW heifers compared to TN heifers (172.5+/-8.9 vs 136.9+/-7.7 micromol/L and 87.8+/-2.4 vs 83.3+/-2.7 mg/100ml for NEFA and glucose, respectively). Time trends of concentrations of estradiol in serum (P<0.01) and hip-height to weight ratios were different (P<0.05) for WW and TN. Birth weights of calves from TN heifers were greater (P<0.06) than calves from WW heifers (42.3+/-2.0 vs 36.9+/-1.8 kg), but average calving difficulty scores were similar for both heifer groups (3.2+/-0.5 vs 2.7+/-0.4). These data suggest that exposing spring-calving cows to reduced effective ambient temperatures during the final 90 d of pregnancy may elevate energy-yielding metabolites in plasma and alter endocrine function. These changes may contribute to reduced birth weight of calves.

Journal Article↗
PubMed2002

Weathering of radiocaesium contamination on urban streets, walls and roofs.

Recent investigations in Russia have emphasised the significance of dose contributions from contamination on urban streets and roof pavings, and, typically to a lesser extent, walls in the urban environment. The crucial factor determining the magnitude of these contributions is the retention of the contamination by the different types of urban surface. Since the Chernobyl accident, a series of long-term field studies has been carried out on urban streets, walls and roofs, to examine the weathering processes of 137Cs on the various surface types. The derived time-functions are applied to estimate resultant long-term doses to inhabitants of an urban centre. The paper highlights the effect on caesium retention of surface material characteristics.

Cesium↗
PubMed2002

Mobility of heavy metals associated with the natural weathering of coal mine spoils.

Knowledge of chemical mobility of heavy metals is fundamental to understanding their toxicity, bioavailability, and geochemical behavior. In this paper, two different methods, i.e. mineralogical means and sequential extractions, were employed to analyze the total contents, existing states, and chemical forms of heavy metals in coal mine spoils. The results demonstrate that the mobility of heavy metals in coal mine spoils depends not only on their existing states and the stability of their host minerals but also on the properties of the coal mine spoils. In the process of coal mine spoils-water interaction, sulfides that contain heavy metals first break down and release metals, which are then adsorbed and complexed by the iron oxyhydroxide colloid resulting from pyrite oxidization and organic matter. During the natural weathering of coal mine spoils, only a small fraction of these metals are released to the environment, and most of them still remains in the residual material.

Biological Availability↗
PubMed2002

Chemical changes and leachate mass balance of municipal solid waste bottom ash submitted to weathering.

A study on the chemical stability of municipal solid waste (MSW) bottom ash submitted to weathering was carried out in order to identify and quantify the physico-chemical maturation mechanisms in a large heap (375 tonnes) over a period of about 18 months. The mineralogy and chemical composition of MSW bottom ash were analysed on fresh and maturated material. Calcite is the predominant newly formed mineral during bottom ash maturation, combined with aluminium hydroxides and various sulphates. Lead and zinc are trapped primarily by newly formed carbonates. Monitoring of the pore water and the outlet leachates revealed a marked contrast in the physico-chemical conditions within the heap and at the outlet. The salinity of the fluids peaked at around 16 g/l within the first few weeks and then progressively decreased to fluctuate between 5 and 8 g/l. Due to the high pH of the pore water, the average concentrations of heavy metals in the heap are high: 42.7, 9.6 and 0.8 mg/l for Cu, Pb and Zn. At the heap outlet, however, the leachates are buffered by carbonate precipitation due to equilibration with atmospheric CO2. Copper complexed as a chloride at the outlet remains at a relatively high concentration (10.2 mg/l), whereas Pb and Zn concentrations are below the limit of detection (<25 microg/l). A mass balance carried out over the 18 months of monitoring indicated that 86% of remobilized material within the heap is evacuated from the system. Within the heap, carbonation trapped 43 and 54% of the calcium and bicarbonate flux. The copper, lead and zinc flux at the heap outlet represent only 34, 18 and 19% of the actual remobilized mass of heavy metals.

Carbon Dioxide↗
PubMed2002

Weathering of a MSW bottom ash heap: a modelling approach.

Establishing plausible predictive scenarios represents a challenge for the long-term evolution of waste such as municipal solid waste bottom ash. These systems are characterized by complex and sometimes poorly understood physico-chemical mechanisms. The long term prediction of the evolution of such systems must be based on a dynamic approach involving their study in space and time. A preliminary outline of a model integrating chemistry and mass transfer is currently being tested by BRGM on the results obtained from a 16-month monitoring survey of a pilot bottom ash heap subjected to meteoric weathering. The model is based on a simplified coupled chemistry-transport approach using mass action laws and Kinetics chemical model (the Networks of Chemical Reactors approach). This modelling approach is used to monitor the evolution in chemical composition of a column of meteoric water percolating through the pilot bottom ash heap. The system is divided into representative elementary volumes (chemical reactors) on the basis of the major chemical and mineralogical zonations identified in the system.

Environmental Pollutants↗
PubMed2001

Response of river otters to experimental exposure of weathered crude oil: fecal porphyrin profiles.

Profiles of porphyrins were characterized in fecal samples from river otters (Lontra canadensis) experimentally exposed to weathered crude oil to determine effects on heme synthesis. Fifteen male river otters were randomly assigned to three groups of five individuals each representing a control group, a low-dosage group that received 5 mg/kg body mass of oil per day, and a high-dosage group that received 50 mg/kg body mass of oil per day. Mean levels of coproporphyrin III (CoproIII) and protoporphyrin IX (ProtoIX) in fecal samples collected from all experimental river otters were higher throughout the experimental period than levels of CoproIII and ProtoIX in fecal samples collected previously at two field sites. No statistically significant differences in levels of CoproIII and ProtoIX were observed between treatment groups, although a trend of reduction in variability in CoproIII was observed in the low- and high-dose groups. We found no relation between levels of CoproIII and ProtoIX, suggesting that the process of disruption that leads to oxidation of the precursors of porphyrins is probably nonlinear. Our results also indicate that the interaction between oiled induced reduction in hemoglobin levels and induction of CYP1A1 corresponded with significantly lower levels of ProtoIX in the fecal samples, possibly representing high demand for ProtoIX. Therefore, while this experiment does not support the use of porphyrin profiles as an individual biomarker, it does suggest that the latter may be valuable when a weight of evidence is used in an ecotoxicological risk assessment in which the interactions between several biomarkers are explored.

Animals↗
PubMed2002

Aqueous vapor extraction: a previously unrecognized weathering process affecting oil spills in vigorously aerated water.

Simple evaporation of spilled oil is usually thought to be restricted to the smaller hydrocarbons (<15 carbons). We show that aeration of oil in water, at 22 degrees C, substantially extends this evaporation, leading to the loss of alkanes up to at least hexatricosane (nC36) and of polycyclic aromatic hydrocarbons with at least four rings (e.g., chrysene and its alkylated forms). This phenomenon is apparently related to steam distillation and should be considered as an important candidate pathway to explain the observed weathering of oil spilled from the OSSA II pipeline into the Río Desaguadero on the Bolivian Altiplano (approximately 3700 m), which occurred during a very turbulent flood.

Bolivia↗
PubMed2002

Photoenhanced toxicity of weathered Alaska North Slope crude oil to the calanoid copepods Calanus marshallae and Metridia okhotensis.

This study investigated the synergistic toxicity of aqueous polyaromatic compounds (PAC) dissolved from crude oil and ultraviolet radiation (UV) in natural sunlight to the calanoid copepods Calanus marshallae and Metridia okhotensis. These copepods were first exposed to low doses (approximately 2 microg of total PAC/L) of the water-soluble fraction of weathered Alaska North Slope crude oil for 24 h and subsequently to low or high levels of natural sunlight. Responses included mortality, impairment of swimming ability, and discoloration of lipid sacs. There was 80-100% mortality and morbidity of C. marshallae exposed to UV and oil as compared to less than 10% effect in oil-only or UV-only treatments. In M. okhotensis, 100% mortality occurred in the UV and oil treatment, 43% mortality and 27% morbidity in the UV-only treatment, and less than 5% effect in the oil-only treatment. Bioaccumulation factors were approximately 8000 for C. marshallae and approximately 2000 for M. okhotensis. The interaction of the effect of PAC and UV radiation was highly significant (P < 0.005) in both experiments.

Animals↗
PubMed2004

Uptake of weathered DDT in vascular plants: potential for phytoremediation.

Since the discovery of its insecticidal properties and its subsequent widespread use, DDT [2,2-bis(chlorophenyl)-1,1,1-trichloroethane] has accumulated in the environment, having a wide range of adverse effects on nontarget species. Due to their hydrophobicity, DDT and other persistent organic pollutants are difficult to remove from contaminated soils, and increasingly so through time as weathering occurs. Phytoremediation is an emerging plant-based technology that may be used to cost-effectively remove or neutralize contaminants in the environment. For some phytoremediation strategies, it must first be possible to translocate hydrophobic chemicals across the root and through the shoot via an aqueous transpiration stream. The objective of this study was to compare the ability of five plant varieties (zucchini, tall fescue, alfalfa, rye grass, and pumpkin) to mobilize and translocate DDT. Plants were grown in the greenhouse in soil contaminated with DDT and its metabolites, DDD and DDE (sigmaDDT refers to all of DDT, DDD, and DDE) at two concentrations (high approximately 3700 ng/g, and low approximately 150 ng/g). All trays were covered with laboratory Parafilm to limit volatilization. Cucurbita pepo species (pumpkin and zucchini) achieved the highest translocation and bioaccumulation factors, and also extracted the highest absolute amounts of sigmaDDT from both the high and low sigmaDDT soils. In the high sigmaDDT soil treatment, pumpkin accumulated 1519 ng of sigmaDDT in the roots and 57,536 ng of sigmaDDT in the shoots, and zucchini accumulated 2043 ng of sigmaDDT in the roots and 35,277 ng of sigmaDDT in the shoots. With the exception of alfalfa and pumpkin, principal component analysis detected no preferential translocation or transformation of sigmaDDT compounds within the plant. The success of the Cucurbita pepo species in this study to extract and translocate such hydrophobic molecules may be related to their high transpiration volume, large above-ground biomass, and composition of root exudates. This suggests potential for their application in phytoremediation.

Biodegradation, Environmental↗
PubMed2003

Effect of simulated rainfall and weathering on release of preservative elements from CCA treated wood.

The release of arsenic from wood pressure-treated with chromated copper arsenate (CCA) can be decreased by application of wood finishes, but little is known about the types of finishes that are best suited for this purpose. This study evaluated the effects of finish water repellent content and ultraviolet (UV) radiation on the release of arsenic, copper, and chromium from CCA-treated wood exposed to simulated rainfall. Deck boards treated with CCA were either left unfinished or dipped in a finish prepared with 1%, 3%, or 5% water repellent. All specimens were exposed to leaching from simulated rainfall, and a subset of specimens was also exposed to UV radiation. The rainfall was collected and analyzed for total elemental arsenic, copper, and chromium. The water repellent significantly decreased the amounts of these elements in the runoff, but for the short duration of this study there was no difference among the three water repellent concentrations. It is possible that water repellent content would have a greater effect over a longer exposure period. Exposure to UV radiation caused a significant increase in leaching from both finished and unfinished specimens. This effect may be a result of increased surface area during weathering as well as loss of fibers caused by UV-induced surface erosion.

Arsenates↗
PubMed2005

Characterization, weathering, and application of sesquiterpanes to source identification of spilled lighter petroleum products.

Biomarkers have become increasingly important for identifying the source of spilled oil, due to their specificity and high resistance to biodegradation. The biomarkers most commonly used in forensic investigations are the high molecular weight (MW) tri- and pentacyclic terpanes and steranes. For lighter petroleum products such as jet fuels and diesels, the refining processes remove most high MW biomarkers from the original crude oil feedstock. The smaller bicyclic sesquiterpanes, however, are concentrated in these products. Sesquiterpanes are ubiquitous components of crude oils and ancient sediments. Examination of GC-MS chromatograms of these bicyclic biomarkers using their characteristic fragment ions (m/z 123, 179, 193, and 207) provides a highly diagnostic means for identifying spilled oil, particularly for lighter refined product samples that are difficult to identify by current techniques. In this work, sesquiterpanes in crude oils and petroleum products are identified and characterized, distributions of sesquiterpanes in oils and refined products are compared, the effects of evaporative weathering on sesquiterpane distributions are examined, and a methodology using diagnostic indices of sesquiterpanes is developed for oil correlation and differentiation. Finally, two case studies are presented to illustrate the unique utility of sesquiterpanes for fingerprinting and identifying unknown diesel spills.

Chromatography, Gas↗