A History of the Production and Use of Carbon Tetrachloride,Tetrachloroethylene, Trichloroethylene and 1,1,1-Trichloroethane in the United States: Part 2—Trichloroethylene and 1,1,1-Trichloroethane

Carbon tetrachloride (CTC), tetrachloroethylene (PCE), trichloroethylene (TCE) and 1,1,1-trichloroethane (TCA) were four of the most widely used cleaning and degreasing solvents in the United States. Part 2 of this article describes the history of TCE and TCA. TCE production in the United States began in the early 1920s. TCE was used as a replacement for petroleum distillates in the dry-cleaning industry, and became the solvent of choice for vapor degreasing in the 1930s. TCE’s use as a degreaser decreased in the 1960s due to toxicity concerns and the increasing popularity of TCA. Significant TCA use began in the 1950s with the development of suitable stabilizer formulations. In the 1990s, TCA was phased out under the Montreal Protocol due to its role in stratospheric ozone depletion.     

Use of the Light Absorption Coefficient to Monitor Elemental Carbon and PM2.5—Example of Santiago de Chile

Abstract

The optical absorption coefficient, particulate matter with an aerodynamic diameter <2.5 μm, and elemental carbon (EC) have been measured simultaneously during winter and spring of 2000 in the western part of Santiago, Chile (Pudahuel district). The optical measurements were carried out with a low-cost instrument recently developed at the University of Santiago. From the data, a site-specific mass absorption coefficient of 4.45 ± 0.01 m²/g has been found for EC. In addition, a mass absorption coefficient of 1.02 ± 0.03 m²/g has been obtained for PM_2.5. These coefficients can be used during the colder months (May-August) to obtain EC concentration or PM_2.5 from a measurement of the light absorption coefficient (σ_a). The high correlation that has been found between these variables indicates that σ_a is a good indicator of the degree of contamination of urbanized areas.

The data also show an increase in PM_2.5 and EC concentration during winter and an increase in the ratio of EC to PM_2.5. When the EC/PM_2.5 ratio is calculated during rush hour (7:00 a.m.-11:00 a.m.) and during part of the night (9:00 p.m.-2:00 a.m.), it is found that the increase is caused by higher concentration levels of EC at night. These results suggest that the rise in the EC concentration is caused by emissions from heating and air mass transport of pollution from other parts of the city, while traffic contribution remains approximately constant.     

Geological characterization and environmental implications of the placement of the Morelia Dump, Michoacán, Central Mexico

The landfill of Morelia, the capital city of the state of Michoacán in central-western Mexico, is located 12 km west of the city and has operated since 1997 without a structure engineered and designed to control the generation in situ of biogas and leachates. A geological evaluation of the landfill site is presented in this paper. The results indicate that the site lacks ideal impermeable subsurface strata. The subsurface strata consist of highly fractured basaltic lava flows (east-west fault and fracture system trend) and sand-size cineritic material with high permeability and porosity. Geochemical analysis of groundwater from Morelia's municipal aquifer shows a high concentration of heavy metals (Cd, Pb, As) exceeding the Mexican environmental regulations, along with the presence of some organic pollutants (phenols). Analyses of samples of the landfill's permanent leachate ponds show very high concentrations of the same contaminants. Samples were taken from the leachate pond and from nearby water-wells during the rainy season (summer 1997) and the dry season (spring 1997, 1998, and 1999). In all cases, the concentration of contaminants registered exceeded the standards for drinking water of the World Health Organization (American Public Health Association, American Water Works Association, and Water Pollution Control Federation, 2000). Some metal contaminants could be leaching directly from the landfill.     

Geological Characterization and Environmental Implications of the Placement of the Morelia Dump,Michoacán,Central Mexico

Abstract

The landfill of Morelia, the capital city of the state of Michoacán in central-western Mexico, is located 12 km west of the city and has operated since 1997 without a structure engineered and designed to control the generation in situ of biogas and leachates. A geological evaluation of the landfill site is presented in this paper. The results indicate that the site lacks ideal impermeable sub-surface strata. The subsurface strata consist of highly fractured basaltic lava flows (east-west fault and fracture system trend) and sand-size cineritic material with high permeability and porosity. Geochemical analysis of groundwater from Morelia’s municipal aquifer shows a high concentration of heavy metals (Cd, Pb, As) exceeding the Mexican environmental regulations, along with the presence of some organic pollutants (phenols). Analyses of samples of the landfill’s permanent leachate ponds show very high concentrations of the same contaminants. Samples were taken from the leachate pond and from nearby water-wells during the rainy season (summer 1997) and the dry season (spring 1997, 1998, and 1999). In all cases, the concentration of contaminants registered exceeded the standards for drinking water of the World Health Organization (American Public Health Association, American Water Works Association, and Water Pollution Control Federation, 2000). Some metal contaminants could be leaching directly from the landfill.     

Carbon Monoxide and Sulfur Dioxide Adsorption on— and Desorption from Glass,Plastic, and Metal Tubings

It was planned to install 305 m (1000 ft) of tubing on a television tower to transport ambient air samples from different height levels to pollutant monitoring instruments at ground level. A feasibility study was undertaken to determine the sorption characteristics of sulfur dioxide and carbon monoxide on various conduit materials. Sorption studies were completed on 30.5 m (100 ft) lengths of 1.3 cm (Y2 in) diam tubings of glass, Teflon, tygon, polypropylene, PVC piping, aluminum, and stainless steel. Final tests were completed on 305 m of 1.9 cm (3/4 in) diam stainless steel tubing. The following variables were investigated: tubing diameter, gas concentration, flowrate through the tubing, temperature, humidity, and the effect of sorption with sulfur dioxide and carbon monoxide alone or together. The parameter ranges studied approximated either atmospheric or air sampling conditions. For carbon monoxide, there was no significant difference between the mean inlet and outlet tubing concentrations under the conditions of the study. With sulfur dioxide, there was neither tubing adsorption nor desorption under the experimental parameters studied, except for tygon, PVC, and aluminum. After a conditioning period with sulfur dioxide, tygon, PVC, and aluminum could also be used as air inlet conduits; tygon is not recommended.     

Frequency of micronuclei and of other nuclear abnormalities in erythrocytes of the grey mullet from the Mondego,Douro and Ave estuaries—Portugal

Fish are bioindicators of water pollution, and an increased rate of their erythrocyte nuclear morphological abnormalities (ENMAs)—and particularly of erythrocyte micronuclei (EMN)—is used as a genotoxicity biomarker. Despite the potential value of ENMAs and MN, there is scarce information about fish captured in Iberian estuaries. This is the case of the Portuguese estuaries of the Mondego, Douro and Ave, suffering from different levels of environmental stress and where chemical surveys have been disclosing significant amounts of certain pollutants. So, the aim of this study was to evaluate genotoxicants impacts and infer about the exposure at those ecosystems, using the grey mullet (Mugil cephalus) as bioindicator and considering the type and frequency of nuclear abnormalities of erythrocytes as proxies of genotoxicity. Sampling of mullets was done throughout the year in the important Mondego, Douro and Ave River estuaries (centre and north-western Portugal). The fish (total n?=?242) were caught in campaigns made in spring–summer and autumn–winter, using nets or fishing rods. The sampled mullets were comparable between locations in terms of the basic biometric parameters. Blood smears were stained with Diff-Quik to assess the frequencies of six types of ENMAs and MN (given per 1,000 erythrocytes). Some basic water physicochemical parameters were recorded to search for fluctuations matching the ENMAs. Overall, the most frequent nucleus abnormality was the polymorphic type, sequentially followed by the blebbed/lobed/notched, segmented, kidney shaped, vacuolated, MN and binucleated. The total average frequency of the ENMAs ranged from 73?‰ in the Mondego to 108?‰ in the Ave. The polymorphic type was typically ≥50 % of the total ENMAs, averaging about 51?‰, when considering all three estuaries. The most serious lesion—the MN—in fish from Mondego and Douro had a similar frequency (≈0.38?‰), which was significantly lower than that in the Ave (0.75?‰). No significant seasonal differences existed as to the MN rates and seasonal differences existed almost only in the Douro, with the higher values in AW. In general, the pattern of ENMAs frequencies was unrelated with the water physicochemical parameters. Considering the data for both the total ENMAs and for each specific abnormality, and bearing in mind that values of MN in fish erythrocytes >0.3?‰ usually reflect pollution by genotoxicants, it is suggested that mullets were likely being chronically exposed to such compounds, even in the allegedly less polluted ecosystem (Mondego). Moreover, data supported the following pollution exposure gradient: Mondego?<?Douro?<?Ave. The scenario and inferences nicely agree with the published data from chemical monitoring.     

Economic,ecological, and health aspects of β-diketonate application in the process of water purification

Environmental Science and Pollution Research - Water pollution is a constant challenge for humanity. Sustainable economic development and environmental protection through a green economy structure...     

Identification and assessment of ship emissions and their effects in the harbour of Göteborg,Sweden

The effect of ship emissions in the urban environment of Göteborg has been studied by multivariate analysis. The simultaneous measurements of relevant gases and sub-micron particles make identification of ship plumes possible. Increased concentrations of these species due to ship emissions are quantified for ships entering the inner part of the harbour. Annual depositions of SO₂ and NO₂ are estimated to be 220 and 115 kg km⁻² yr⁻¹, respectively. Exposure of transient particles (less than 0.1 μm in diameter) to this part of the harbour increased by a factor of 3 in number concentration when a ship plume was recorded. Ni, Pb, V and Zn are shown to have positive correlation with NO emissions from ships.     

Concentrations,atmospheric partitioning,and air–water/soil surface exchange of polychlorinated dibenzo-p-dioxin and dibenzofuran along the upper reaches of the Haihe River basin,North China

Polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/PCDF) were overall measured and compared in ambient air, water, soils, and sediments along the upper reaches of the Haihe River of North China, so as to evaluate their concentrations, profiles, and to understand the processes of gas–particle partitioning and air–water/soil exchange. The following results were obtained: (1) The average concentrations (toxic equivalents, TEQs) of 2,3,7,8-PCDD/PCDF in air, water, sediment, and soil samples were 4,855 fg/m³, 9.5 pg/L, 99.2 pg/g dry weight (dw), and 56.4 pg/g (203 fg TEQ/m³, 0.46 pg TEQ/L, 2.2 pg TEQ/g dw, and 1.3 pg TEQ/g, respectively), respectively. (2) Although OCDF, 1,2,3,4,6,7,8-HpCDF, OCDD, and 1,2,3,4,6,7,8-HpCDD were the dominant congeners among four environmental sinks, obvious discrepancies of these congener and homologue patterns of PCDD/PCDF were observed still. (3) Significant linear correlations for PCDD/PCDF were observed between the gas–particle partition coefficient (K _p) and the subcooled liquid vapor pressure (P _L ⁰) and octanol–air partition coefficient (K _oa). (4) Fugacity fraction values of air–water exchange indicated that most of PCDD/PCDF homologues were dominated by net volatilization from water into air. The low-chlorinated PCDD/PCDF (tetra- to hexa-) presented a strong net volatilization from the soil into air, while high-chlorinated PCDD/PCDF (hepta- to octa-) were mainly close to equilibrium for air–soil exchange.     

Stratospheric ozone,global warming,and the principle of unintended consequences—An ongoing science and policy story

Supplemental Materials: Supplemental materials are available for this paper. Go to the publisher's online edition of the Journal of the Air & Waste Management Association.      

Distribution,persistence, and fate of mexacarbate in the aquatic environment of a mixed‐wood boreal forest

Abstract

The distribution and persistence of aerially applied mexacarbate were studied in a New Brunswick aquatic forest environment after spraying twice at a dosage of 70 g A.l./ha using a fixed‐wing aircraft. Average droplet density (drops/cm²) and ground deposition (g A.1./ha) between the two applications differed considerably. The values for the first and second applications were 1.7 and 0.73, and 5.2 and 2.0, respectively; but the average NMD (20 μm) and VMD (36 μm) for both applications were nearly the same. The maximum 1‐h postspray concentrations of mexacarbate in the stream and pond waters were 0.73 and 18.74 ppb, respectively. Concentrations fell rapidly to below detection limits within 12 h in stream and within 3 d in pond water. Cattails (Typha latifolia), manna grass (Glyceria borealis) and bog moss (Sphagnum sp.) collected from the pond contained peak 1‐h postspray concentrations of 720, 482 and 81 ppb, respectively. The concentration levels decreased rapidly and the average half‐lives of the chemical in them were about 3.9, 8.5 and 2.0 h. Bog moss, stream moss (Fontinalis sp.), watercress (Nasturtium officinalis), buttercup (Ranunculus aquatilis) and green alga (Drapamaldia sp.) sampled from the stream sites did not contain measurable levels of mexacarbate. Also, caged and wild tadpoles (Rana clamitans melanota) from the pond, and brook trout (Salvelinus fontinalis) (caged and wild), Atlantic salmon (Salmo salar) (wild) and mayfly nymphs (Ephemeralla sp.) collected from the stream did not contain any of the material. Mexacarbate was not detected in stream and pond sediments. The demethylated products, 4‐methylamino and 4‐amino‐3,5‐xylyl methylcarbamates and the phenol, 4‐dimethylamino‐3,5‐xylenol, were frequently detected as metabolites in water and in the aquatic plants. The presence of these compounds showed that demethylation and hydrolytic routes are the major metabolic pathways for the dissipation of mexacarbate from these substrates.     

Bio- and toxic elements in mushrooms from the city of Umeå and outskirts,Sweden

Edible mushrooms (Albatrellus ovinus, Boletus edulis, Clitocybe odora, Gomphidius glutinosus, Leccinum scabrum, Leccinum versipelle, Lycoperdon perlatum, Suillus bovinus, Suillus luteus, and Xerocomus subtomentosus) collected from unpolluted areas of the city of Umeå and its outskirts in the northern part of Sweden were examined for contents of toxic metallic elements (Cd, Pb, and Ag) and essential macro- and microelements (K, Na, Ca, Mg, Cu, Fe, Mn, and Zn) using a validated method and a final measurement by flame atomic absorption spectroscopy (F-AAS). The median values of the toxic metallic element concentrations (in mg kg^?1 dry biomass, db) ranged from: 0.12–3.9, 0.46–5.1, and 0.91–6.2 for Ag, Cd and Pb, respectively. For the essential metallic elements, the median values of concentrations ranged from: 24000–58000, 15–2000, 59–610, 520–1900, 2.0–97, 16–150, 15–120, and 4.3–26 mg kg^?1 db for K, Na, Ca, Mg, Cu, Zn, Fe, and Mn, respectively. The baseline concentrations of the metallic elements determined in mushrooms were mainly affected by the fungal species. The assessed probable maximal dietary intake of Cd (0.002 mg kg^?1 body mass) solely from a mushroom meal was only slightly below a revised value of the tolerable weekly intake for this element, while for Pb (0.003 mg kg^?1 body mass) it was tenfold below the provisionally tolerable weekly intake.     

Is Gray Water the Key to Unlocking Water for Resource-Poor Areas of the Middle East,North Africa,and Other Arid Regions of the World?

Support for the use of treated gray water as an alternative water resource in the Middle East and North Africa is high, especially given the lack of religious restrictions against its use, but several obstacles have kept application of treated gray water near 1 % in some areas. The largest of obstacles include the cost of treatment and the ambiguity surrounding the health safety of gray water and treated gray water. This paper aims to provide an overview of current gray water practices globally, with specific focus on household-level gray water practices in the Middle East and North Africa region, and highlight the need for cost reduction strategies and epidemiological evidence on the use of household-level gray water and treated gray water. Such actions are likely to increase the application of treated gray water in water-deprived areas of the Middle East and North Africa.     

A Statistical Analysis of the Los Angeles Ambient Carbon Monoxide Data 1955–1972

This paper presents a statistical analysis of some aspects of the ambient carbon monoxide data from 1955 to 1972 recorded at seven appropriately distributed locations in the Los Angeles Basin. Using modern time series methods and graphical techniques, an overall trend analysis of the movement of CO is given. Of special interest is a detailed study of the effect on the observed concentration level of CO due to (i) a change in the method of calibration of the measuring instrument In April 1968 and (ii) various control measures introduced since 1966. Also presented is an analysis of the seasonal variation of CO and the diurnal variation in weekdays and weekends. A major purpose of this study is to assess the influence of meteorological variables on the concentration level of the pollutant. Appropriate mathematical models are developed which relate CO to inversion base height, maximum mixing height, wind speed and direction, and traffic pattern. In addition, an analysis of the meteorological conditions during the days in which hourly concentration level of CO exceeded the Federal Air Quality Standard is given.     

Soybean production and conversion of tropical forest in the Brazilian Amazon: the case of Vilhena, Rondônia

The recent rise in Brazilian soybean production has generated concern among the environmental community and some authors that natural tropical environments of the Amazon Basin are being converted to soybean fields. Proponents of soybean production counter that soybeans represent a viable agricultural commodity for the region; environmental concern is unwarranted, because new soybean fields are replacing already deforested or otherwise transformed lands. Both arguments have been made without comprehensive study and measure of land-use/land-cover (LULC) in areas undergoing expansion of soybean production. This case study, conducted in the municipality of Vilhena, Rond?nia, Brazil, in the southwestern Amazon Basin, uses remote sensing to evaluate the LULC accompanying this municipality's large growth in soybean production from 1996 to 2001. Forests are being converted for soybean production, but most of the production increase appears attributable to slight expansion of already existing fields, conversion of already deforested land, and higher yields.     

Poland’s environment - past,present and future state of the environment in the vistula and odra river basins

In the middle of the last century in the case of many river basins, it became obvious that the targets of the Helsinki-Commission (HELCOM) concerning a 50% reduction of nitrogen and phosphorus inputs to the Baltic Sea had not been reached. Such conclusions could be derived from the observed loads. But the measurements regarding the analysis were not sufficient to determine what the reasons for this report were, what has to be done to fulfil this agreement and to evaluate the time at which the targets can be reached. This contribution presents the current state of Polish surface water quality as well as results of modelling nutrient and heavy metal emissions into the two biggest Polish river basins: Vistula and Odra, which both cover approximately 90% of Poland's territory.     

Influence of usage and chemical–physical properties on the atmospheric transport and deposition of pesticides to agricultural regions of Manitoba,Canada

This study quantified the masses of 14 pesticides deposited as wet (precipitation) versus dry (gaseous and particle) atmospheric deposition at a research farm in southwestern Manitoba, Canada. The concentration in air of these pesticides was also measured. Total bulk deposition amounts (wet + dry) ranged from 0.009 to 2.3 μg m^?2 for the 12 pesticides detected, and for the six pesticides with both wet and dry deposition detections, dry deposition contributed 12–51% of the total deposition over the crop growing season. Although not applied at the site, eight herbicides registered for use in Canada, as well as lindane (γ-HCH), were all frequently detected (92–100%) in the 12 air samples analyzed during the crop growing season, with by-product isomer α-HCH (75%), clopyralid (50%) and atrazine (8%) detected to a lesser extent. The chemical’s physicochemical properties and the relative mean mass of each agricultural pesticide applied in the province of Manitoba and in a 13 km radius were significant parameters in explaining the trends in the concentrations of pesticides detected in our samples. The important contribution of dry deposition to total pesticide deposition warrants greater attention in arid and semi-arid areas such as the Prairie Region of Canada, also because under a changing climate this region is estimated to experience more severe droughts while the more favorable conditions predicted for pest infestations could lead to increased pesticide applications in agricultural and urban areas.     

Do tailings from the Mariana,MG (Brazil), disaster affect the initial development of millet,maize, and sorghum?

Environmental Science and Pollution Research - The collapse of the Fundão dam in Mariana, MG, in 2015 resulted in the overflow of more than 50 million m3 of mud containing mine tailings,...     

Effect of phenobarbital and polychlorinated biphenyls on the toxicity and disposition of 1,2,4,5‐tetrachlorobenzene in the rat

Soil avoidance by earthworms has been generally considered a relevant and sensitive endpoint for assessing soil contamination by xenobiotics. However, when pesticide ecotoxicological assessment is concerned, the sensitivity of the recently standardized avoidance assay has been questioned. We hypothesized that this controversy may be due to the specific pesticide mode of action of the chemicals used rather than reveal inconsistencies in the test feasibility, i.e. provided that no pesticides interfering with neuronal pathways are tested, this bioassay should keep expected high levels of sensitivity. In this study, the avoidance behaviour of the earthworm Eisenia andrei under exposure to the carbamate insecticide methomyl [S-methyl N-(methylcarbamoyloxy)thioacetimidate] was linked to the corresponding acetylcholinesterase (AChE) inhibition. Significant AChE inhibition occurred at lower concentrations (from 0.86 mg Kg^?1 onwards) than significant avoidance of spiked soil (from 5.62 mg Kg^?1 onwards). This indicates that assessments regarding pesticides that have neurotoxic activity may be biased if behavioral endpoints are selected. Despite theoretical hypothesis that have been raised, this should be the first study providing preliminary experimental evidence on such a link between avoidance behavior and neuronal impairment levels in earthworms. Further studies are ongoing that should refine conclusions of this study.