Sulfur dioxide (SO₂) is basically resulted from emission of fossil fuel. The ammonia washing is of methods used to remove SO₂ from fuel gas. Several wastewaters contain high ammonia concentrations causing the various problems at wastewater treatment or receiving environment. The synthetic wastewater containing NH₃ was sprayed down as flue gas moved up in the scrubber so that it could be a reaction between SO₂ and NH₃. The effect of NH₃ concentration and pH on SO₂ removal was determined. SO₂ was decreased from about 1,000 to 0, 36, 49 and 66 ppm at NH₃ concentrations of 328, 88, 32 and 9 mg l⁻¹, respectively. While SO₂ of 1,000 ppm was completely treated at 328 mg NH₃ l⁻¹, pH was around 7.16 at the end of process. Consequently, it was recognized that this process could be used for both the SO₂ removal and the wastewater neutralization.

As global water resources decline, reuse of domestic greywater for the irrigation of home gardens is quickly becoming widespread in many parts of the world. However, the sanitary implications of reusing greywater to water edible crops remain uncertain. This study examined the benefits and risks associated with domestic greywater reuse for the purposes of vegetable garden irrigation. Untreated (settled only) and treated (settling and slow sand filtration) greywater collected from a family home was analyzed for basic water quality parameters over a period of 8 weeks. During that time, both greywaters were used to irrigate individually potted plots of lettuce, carrots, and peppers in a greenhouse. Tap water was used as control. Upon maturity, plants were harvested and the edible portions tested for fecal coliforms and fecal streptococci, common indicators for the presence of pathogenic microorganisms. Heavy metals were not detected in the greywater, but both fecal coliforms and fecal streptococci were present in high levels, averaging 4 x 10⁵/100 mL and 2,000/100 mL of greywater, respectively. Despite these high counts, no significant difference in contamination levels was observed between crops irrigated with tap water, untreated greywater, and treated greywater. Fecal coliform levels were highest in carrots and fecal streptococcus levels were highest on lettuce leaves. However, contamination levels for all crops were low and do not represent a significant health risk. Plant growth and productivity were unaffected by water quality, owing to the low N, P, and K levels of the greywater. These results reinforce the potential of domestic greywater as an alternative irrigation source.

Cloudwater samples have been collected for the first time at a high-elevation site in the US interior Southwest. Cloud samples were collected at the summit of Mt. Elden near Flagstaff, Arizona. The samples were analyzed for pH, ionic composition, trace metals, organic carbon content, and volatile organic compounds. All of the samples showed high pH values (5.12-6.66), which appear to be the result of soil/crustal acid-neutralizing components. Ammonium and nitrate were the dominant ionic species. Organic carbon concentrations ranged from 3 to 18 mg/l. Volatile aromatic compounds (toluene, ethylbenzene, and xylenes) were detected, although they did not contribute significantly to the dissolved organic matter (<1% of dissolved organic carbon). Still, their aqueous-phase concentrations were substantially higher than equilibrium partitioning from the gas phase would suggest. Metal concentrations were high when compared to other cloud studies in remote areas. Overall, with the exception of pH, the cloud chemistry showed marked inter-event variability. The source of the variability was investigated using NOAA HYSPLIT dispersion calculations. Like the cloud composition, the air mass back trajectories differed widely from event to event, and consistently, air masses that passed over highly urbanized areas had higher trace metal, organic, and ion concentrations than more pristine air masses.

The potential of almond shells was assessed for adsorption of heavy metal ions such as Pb²⁺ and Cd²⁺ from aqueous solution. Almond shells were pretreated separately with 0.4 mol/L NaOH, 0.4 mol/L HNO₃, and distilled water and their adsorption abilities were compared. Batch adsorption experiments were carried out as a function of the initial ion concentration, pH, and adsorbent dosage. Adsorption isotherms of metal ions on adsorbents were determined and correlated with common isotherm equations such as Langmuir, Freundlich, and BET models. The alkali-modified almond shells had adsorption capacities for Pb²⁺ from 2 to 9 mg/g and for Cd²⁺ from 2 to 7 mg/g, which was much higher than acid- and water-pretreated adsorbents. Experimental results showed that the best pH for adsorption was 5-6 and the adsorption values decreased with lowering pH. Isotherm models indicated the best fit for Langmuir model for alkali-modified almond shells. In comparing the parameters of the models, it was observed that the affinity of almond shells for adsorption of lead is stronger than affinity for adsorption of cadmium.

Many management strategies to improve the health of Chesapeake Bay focus on reducing losses of sediments and nutrients from agricultural land. Plot-scale studies have suggested that Best Management Practices (BMPs) reduce these losses, and natural resource managers have since supported implementation of a variety of BMPs on farms in the Chesapeake Bay watershed over the last two decades. As a test of the efficiency of these BMPs at the watershed scale, all farms within German Branch watershed had BMPs implemented in the early 1990s. Using water quality from two past monitoring programs (i.e., in 1986 and 1991-1995) and current water quality monitoring (i.e., collected 2003-2006), we detected a 28% decrease in baseflow P concentrations a decade after BMP implementation. There were no significant changes in nitrate or total nitrogen concentrations between BMP implementation and the most recent sampling. However, the significant rate of increase (~0.08 mg N L⁻¹ year⁻¹) from 1986 to the 1990s did not continue to 2003-2006 baseflow conditions, which suggests that BMPs may have suppressed the rate of increase in nitrogen observed earlier in German. These data suggest that other management practices that increase agricultural N losses and natural processes that attenuate N losses at the watershed scale may obscure significant N reductions by current BMPs in the watershed.

We tested the hypothesis that there would be measurable losses of phosphorus (P) from surficial sediments of Upper Klamath Lake (UKL), Oregon, if sediments were a source of P during an algal bloom. We compared concentrations of total and forms of P at various depths in cores collected before and after the onset of a large Aphanizomenon flos-aquae bloom. Concentrations of inorganic P were determined in extraction solutions of MgCl₂ (1 M, pH 8), citrate-dithionite-bicarbonate, and 1 M HCl. Sediments below 2 cm were dominated by residual P which is defined as total P minus inorganic P. During the study period, data from the top 2-cm of sediment indicated (a) significant decrease in total P concentration, primarily associated with iron oxyhydroxides at one site, and (b) significant increase in total P concentration associated with residual P at a second site. Data from two other sites indicated no net changes in concentrations of total P.

The paper presents the results of a study in the region Dübener Heide (Central Germany) testing the suitability of field measurements of magnetic susceptibility for the detection of historical fly-ash deposition. The measurements supported the verification of historically documented deposition zones along an emission gradient. Mean values, standard deviation, and coefficient of variation can be used to characterize the former deposition zones, although the study revealed several problems, which will be the subject of future work: (1) the volume susceptibility measurements used in the study do not allow the calculation of the actual fly-ash amount stored in the soil and thus must be calibrated with correction factors from laboratory measurements; and (2) measurements in regions with similar conditions but without fly-ash deposition are needed to obtain reference values for the natural range of magnetic susceptibility.

The DNA damage and cytotoxicity induced by CdCl₂ solutions and soils anthropogenically contaminated with heavy metals were studied using the micronucleus (MN) test. Vicia faba, a plant model widely used in liquid exposure assays, was adapted for direct exposure to a solid phase. In addition, the MN assay was adapted to a new wild plant system, the white clover (Trifolium repens). The results obtained after exposure to CdCl₂ solutions confirmed that V. faba root cells were a sensitive model and revealed that T. repens root cells were not appropriate for the detection of micronuclei (although they were highly sensitive to the cytotoxic effect of CdCl₂). Concerning the results observed after direct exposure to contaminated soils (solid-phase exposure), the MN frequency scores in V. faba root cells were increased in a statistically significant and dose-related manner compared to the control plants. Regarding T. repens root cells, this solid phase exposure confirmed that this model is not appropriate for use in the micronucleus assay.

The chemical characteristics of the Urauchi River water in Iriomote Island National park, Okinawa, Japan have been studied. Concentrations of PO₄ ³⁻, NO₂ ⁻, and NH₄ ⁺ were barely detectable. We compared the concentration ratios of Mg²⁺/Na⁺, HCO₃ ⁻/Na⁺, and Ca²⁺/Na⁺ in the Urauchi River to those of 60 large rivers in the world and indicated that the chemical composition of the river is most likely formed by the binary mixing of sea salt components and silicate rock weathering components. Although rock weathering in the catchments area is driven by both H₂CO₃ and H₂SO₄, the role of H₂CO₃ is dominant. The percentages of the concentration of each cation in the river water are almost the same as those of other rivers with drainage areas consisting of silicate rock and sandstone. Thus, the Urauchi River shows the typical chemical characteristics of a river in a silicate rock area that includes sandstone.

Current-year, 1-year-old, and 2-year-old needles were collected separately on 37 black spruce (Picea mariana Mill. B.S.P.) trees located on a heavy metal contamination gradient around the smelter in Murdochville, Québec (Canada). Needles were analyzed separately by year for the concentrations of Pb and Cu, a nonessential and an essential metal, respectively. Lead concentrations increased significantly with needle age in the highly contaminated area near the smelter. In contrast, Cu concentrations decreased with needle age in the same area. Our results support the hypothesis that the passive sequestration of toxic metals in the senescing foliage is a detoxification process contrasting with the active translocation of essential metals in the nonsenescent part of the foliage.