Regressions of aluminum against potentially toxic elements in the sediments of freshwater aquatic systems in Louisiana were used to distinguish natural variability from anthropogenic pollution when elemental concentrations exceeded screening effects levels. The data were analyzed using geometric mean model II regression methods to minimize, insofar as possible, bias that would have resulted from the use of model I regression. Most cadmium concentrations exceeded the threshold effects level, but there was no evidence of an anthropogenic impact. In Bayou Trepagnier, high concentrations of Cr, Cu, Pb, Ni, and Zn appeared to reflect anthropogenic pollution from a petrochemical facility. In Capitol Lake, high Pb concentrations were clearly associated with anthropogenic impacts, presumably from street runoff. Concentrations of potentially toxic elements varied naturally by as much as two orders of magnitude; hence it was important to filter out natural variability in order to identify anthropogenic effects. The aluminum content of the sediment accounted for more than 50% of natural variability in most cases. Because model I regression systematically underestimates the magnitude of the slope of the regression line when the independent variable is not under the control of the investigator, use of model II regression methods in this application is necessary to facilitate hypothesis testing and to avoid incorrectly associating naturally high elemental concentrations with human impacts.

Cryptosporidium parvum oocysts may reach soil through direct deposition of human or animal fecal material, irrigation with raw wastewater or untreated effluents, and contaminated runoff. Examination of soil samples for oocyst presence is of primary importance in order to prevent secondary contamination of crops and groundwater. Several methods were proposed for oocyst recovery from soil samples; however, their efficiency was very low. In the present study, four known methods used to recover oocysts from water and fecal samples (sedimentation, sedimentation with reduced water content, sucrose floatation, water-ether separation) were compared to a method used in the past to recover bacterial spores from bottom sediments (two-phase separation). The two-phase separation technique proved to be the best method of choice resulting in a recovery average of 61.2 ± 15.6%. According to this method, the lowest and highest recoveries were 37% to 95%, respectively. Two other important outcomes were observed with the soil experimental set-up: (1) recovery efficiency is influenced by oocyst viability (high viability was directly correlated with increased recovery efficiency) and (2) high sand content of soil samples reduced oocyst recovery by its detrimental effect on oocyst viability.

This study was conducted to determine the metal (Ag, Al, As, Cd, Co, Cu, Fe, Mn, Ni, Pb, Sb, Zn) tolerance and uptake of Mitchell grasses when grown on waste rocks and tailings of a base metal mine, Australia. The objective of conducting such phytoremediation studies was to gain data relating to the implementation and effectiveness of capping and revegetation strategies for mine waste repositories in regions of native grasslands. Pot trials demonstrate that Mitchell grasses are metal tolerant and have the ability to accumulate significant concentrations of metals (Pb, Zn) into their above-ground biomass. Concentrations of metals in Mitchell grasses were evaluated in terms of maximum allowable dietary levels in livestock. The pot trial project revealed that if Mitchell grasses were to be used for mined land reclamation and were grown on tailings, the grasses could potentially accumulate large quantities of Zn in their tissue, potentially causing harmful effects on animals feeding on them. Hence, it is undesirable that Mitchell grasses are grown on and their root system come in contact with tailings with elevated level of Zn. Otherwise, the species may accumulate phyto- and zootoxic concentrations of Zn. The metal tolerance, the tendency to accumulate metals in the above-ground biomass and the significant root penetration depth of Mitchell grasses have implications for the design of tailings storage facilities. Capping of waste repositories, containing elevated metal concentrations and using a cover system without capillary breaks, clay layers or alternative strategies, may not be sustainable in the long term. The application of phosphate amendments to tailings may represent an alternative strategy to limit the uptake of metals by Mitchell grasses. The pot trials prove that the addition of phosphate to mine wastes decreases the bio-availability of metals in these materials and reduces the Pb and Zn concentration in Mitchell grasses growing on them. Thus, the addition of phosphate amendments to the top layers of metalliferous mine wastes may represent an alternative waste management strategy.

This study assessed the arsenic and heavy metal contaminations of agricultural soils around the tin and tungsten mining areas in Dai Tu district in northern Vietnam. Among the examined elements, high total contents of As and Cu were found in the agricultural fields at both tin and tungsten mining sites. Although the major part of the accumulated As and Cu were bound by various soil constituents such as Fe and Mn oxides, organic matter, and clay minerals, increases in water soluble As and Cu were observed, especially for the paddy fields. The results suggest that, in the studied area, As and Cu dispersion from their pollution sources into farmlands is mainly via fluvial transportation of mine waste through streams that cross the paddy fields around the tin mining area, and soil erosion at the tea fields located at lower positions of the slope in the tungsten mining area.

The paper presents results of a preliminary study on mercury concentration in the air carried out in the period of October 2006 to April 2007 at sampling sites located in the cities of Gliwice and Zabrze in the region of Upper Silesia--Poland's largest urban and industrial agglomeration. The study comprised physical (particulate matter-gaseous phase) and chemical speciation of gaseous mercury. Mercury concentration data related with two fractions of particulate matter: PM2.5 and PM10 are reported. The performed measurements indicated that the average monthly concentrations of the total mercury were in the range of 4.1 to 9.1 ng m⁻³. The highest mercury concentration was observed in winter, especially in periods of low precipitation. The investigation of ambient mercury distribution indicated that 4.6% to 9.8% of the total mercury present in the air was bound to particulate matter. It has been also observed that 77% of mercury in PM10 was bound to the respirable PM2.5 fraction. Chemical speciation analysis showed that elemental mercury presented 96.1% up to 99.3% of the total gaseous mercury concentration in the air.

In order to assess as to whether treated textile effluent could be safely used to irrigate some winter vegetables, growth room experiments were conducted. Varying levels of treated and untreated textile effluents were applied to germinating seeds of some winter vegetables and their effect was evaluated on germination and early growth stage using seed germination, growth, and biochemical attributes. From the results, it was obvious that textile effluent reduced seed germination and early growth of all vegetables. However, this effect was more pronounced at the highest concentration of textile effluent. Furthermore, treated textile effluent did not show any inhibitory effect on seed germination of all vegetables. Photosynthetic pigments such as chlorophyll a and b, and protein contents were higher in the leaves of all vegetable plants irrigated with treated textile effluent than those of supplied with untreated textile effluents. It has been observed that heavy metals were lower in concentration in treated textile effluent as compared with untreated textile effluent. However, germination and growth responses of all three vegetables were different to treated or untreated textile effluents. Furthermore, the Raphanus sativus ranked as tolerant followed by Brassica campastris and Brassica napus based on germination and growth responses. In conclusion, in view of shortage of water, textile effluent could safely be used for irrigation to vegetables after proper processing.

Silicon presents a close relationship with the amelioration of heavy metals phytotoxicity. However, mechanisms of Si-mediated alleviation of metal stress remains poorly understood. This work aimed at studying the relationship between the accumulation of Si, Cd, and Zn and the tolerance and structural alterations displayed by maize plants grown on a Cd and Zn enriched soil treated with doses of Si (0, 50, 100, 150, and 200mg kg⁻¹) as calcium silicate (CaSiO₃). The results showed that the maize plants treated with Si presented not only biomass increasing but also higher metal accumulation. Significant structural alterations on xylem diameter, mesophyll and epidermis thickness, and transversal area occupied by collenchyma and midvein were also observed as a result of Si application. The deposition of silica in the endodermis and pericycle of roots seems to play an important role on the maize tolerance to Cd and Zn stress.

This paper investigates the pollution load of selected trace elements in 32 soil samples collected around 21 different mining areas of the Iberian Pyrite Belt (Southwest Spain), integrating chemical data with soil parameters to help understand the partitioning and mobility of pollutants. The minesoils are depleted in acid neutralising minerals and show limiting physicochemical properties, including low pH values and very high anomalies of potentially hazardous metals. The total concentrations of As (up to 1,560 mg kg⁻¹) and certain heavy metals (up to 2,874 mg kg⁻¹ Cu, 6,500 mg kg⁻¹ Pb, 6,890 mg kg⁻¹ Zn, 62 mg kg⁻¹ Hg and 22 mg kg⁻¹ Cd) are two orders of magnitude above the soil background values. The close association of Cd and Zn with the carbonate content in lime-amended minesoils suggests metal immobilisation through adsorption and/or co-precipitation mechanisms, after acid neutralisation, whereas As and Pb are similarly partitioned into the soil and mostly associated with iron oxy-hydroxides.

Biomass cogeneration is widely used for district heating applications in central and northern Europe. Biomass trigeneration on the other hand, constitutes an innovative renewable energy application. In this work, an approved United Nations Framework Convention on Climate Change baseline methodology has been extended to allow the examination of biomass trigeneration applications. The methodology is applied to a case study in Greece to investigate various environmental and financial aspects of this type of applications. The results suggest that trigeneration may lead to significant emissions reduction compared to using fossil fuels or even biomass cogeneration and electricity generation. The emissions reduction achieved may be materialized into a considerable revenue stream for the project, if traded through a trading mechanism such as the European Union Greenhouse Gas Emission Trading Scheme. A sensitivity analysis has been performed to compensate for the high volatility of the emission allowances' value and the immaturity of the EU Trading Scheme, which prevent a reliable estimation of the related revenue. The work concludes that emission allowances trading may develop into one of the major revenue streams of biomass trigeneration projects, significantly increasing their financial yield and attractiveness. The impact on the yield is significant even for low future values of emission allowances and could become the main income revenue source of such projects, if emission allowances increase their value substantially. The application of trigeneration for district energy proves to lead to increased environmental and financial benefits compared to the cogeneration or electricity generation cases.

The effects of poor indoor air quality and mould growth in working environment are major problems in built environment, and there is a need to look for improvement of the health, comfort and productivity of the building occupants. Airborne mould sampling studies were conducted in a reference building located in Rockhampton, Central Queensland, Australia. Both indoor culturable and mould spore levels were observed. It was found through the indoor-outdoor ratios of the species that indoor concentrations are mostly related to the outdoor mould levels. The moulds differ in their relative humidity and temperature requirements to support surface growth. Indoor humidity has a significant effect on occupants comfort, perceived air quality, occupants' health, building durability, emissions and energy efficiency. Practical hygrothermal simulation models are employed to analyse the combined heat and moisture behaviour within the built environment. A review of the current modelling options available to predict building performance based on energy and mass transport simulation is presented, and then a case study is presented with the assessment of indoor built environment to avoid mould problem.