Photocatalytic methods were applied to remove the recalcitrant or toxic pollutants from the water. The two models of wastewater containing either non-ionic surfactant Triton X-100 or commercially available wash-up liquid were tested in a self-constructed band reactor during the laboratory studies. The photocatalyst, being typed TiO₂, was supported by porous Al₂O₃ and modified by the addition of Cu, Fe, Zn, Ni, Mo or Co. The photocatalysts were characterised by N₂ adsorption–desorption, XRF, XRD, SEM-EDX, Raman and UV–Vis spectroscopy. All catalysts were efficient in the photocatalytic oxidation of surfactants, and they enabled at least 85 % COD reduction. TiO₂/Al₂O₃ photocatalysts modified by the transition metals were efficient only for more complicated compositions of surfactants. The effect of H₂O₂ (0.01 vol.%) addition was also examined and compared with a type of compound and catalyst used—in this case a positive effect for Triton X-100 was only observed over the photocatalyst modified by Ni. When it comes to the wash-up liquid photoremoval, all studied photocatalysts seem to be slightly influenced by H₂O₂ addition. It was also observed that it is not economically justified to conduct such treatment for more than 2 h.

Atmospheric carbonyl sulfide (COS) mixing ratios measured over 24 h during five summer campaigns (2003–2007) in a forest at the foot of Mt. Fuji, Japan (35°21′ N, 138°43′ E; 1,300 m above sea level, a.s.l.) and at the summit (3,776 m a.s.l.) were compared. COS levels were lower at the foot than at the summit during four out of five summer campaigns. The ratios of COS mixing ratios at the foot of Mt. Fuji to those at the summit ranged from 0.7 to 0.9. These results provide evidence of biological consumption of COS in the East Asian atmospheric boundary layer. We also measured the vertical profile of ambient COS below the forest canopy. These data showed a clear gradient of COS mixing ratio: in the lowermost 1 m of the boundary layer, COS mixing ratios decreased markedly downward. Two of the different kinds of vertical distribution of COS presented here support the role of soil as a sink of atmospheric COS described by previous research using dynamic enclosure experiments.

The total concentration and size distribution of bioaerosols in three different types of housing (single room in shared accommodation [type I], single bedroom flat in three-storey building [type II] and two- or three-bedroom detached houses [type III]) was assessed during the winter. This research was an extension of a previous study carried out in the summer. The measurement campaign was undertaken in winter 2008 and 30 houses were sampled. Samples were taken from kitchens, living rooms, corridors (only in housing type I) and outdoors with an Anderson 6 stage viable impactor. In housing type I, the total geometric mean concentration was highest in the corridor for both bacteria and fungi (3,171 and 1,281 CFU/m³, respectively). In type II residences, both culturable bacteria and fungi were greatest in the living rooms (3,487 and 833 CFU/m³, respectively). The living rooms in type III residences had largest number of culturable bacteria (1,361 CFU/m³) while fungi were highest in kitchens (280 CFU/m³). The concentrations of culturable bacteria and fungi were greater in mouldy houses than non-mouldy houses. A considerable variation was seen in the size distribution of culturable bacteria in type I residences compared to types II and III. For all housing types more than half of culturable bacterial and fungal aerosol were respirable (<4.7 μm) and so have the potential to penetrate into lower respiratory system. Considerable variation in concentration and size distribution within different housing types in the same geographical region highlights the impact of differences in design, construction, use and management of residential built environment on bioaerosols levels and consequent varied risk of population exposure to airborne biological agents.

The effects of a five-pesticide mixture on pesticide accumulation, phytohormone levels (indole-3-acetic acid, gibberellic acid, jasmonic acid, and salicylic acid), pigment contents (total chlorophyll and carotenoid), antioxidant enzyme (catalase and guaiacol peroxidase) activities, lipid peroxidation product (malondialdehyde), and DNA profiles were investigated in the leaves of Veronica beccabunga. Laboratory-acclimatized plants were treated with a mix of five pesticides (atrazine, disulfoton, chlorpyrifos, metalaxyl, and ethion) in doses of 50 ppt, 1 ppb, 100 ppb, and 1 ppm for 1, 3, and 6 days. The accumulation of each pesticide, from highest to lowest, was as follows: chlorpyrifos, atrazine, metalaxyl, disulfoton, and ethion. The amounts of total chlorophyll and protein decreased with increased pesticide concentration. Antioxidant enzyme activities and malondialdehyde amount increased linearly with increasing pesticide exposure. However, the highest pesticide concentration caused decreases in guaiacol peroxidase (POD) activity and malondialdehyde (MDA) content at all treatment times. Both jasmonic and salicylic acid levels increased with pesticide exposure and decreased gradually after. It was also determined that application of the pesticide mixture affected the DNA profiles of V. beccabunga. The most band changes were detected on the sixth day of treatment.

Polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) are both classes of persistent organic pollutants with potential major health and environmental concerns. Many PBDE- and PFC-containing products are ultimately discarded in landfills. In samples from 28 landfills and dumpsites across Canada, PBDEs and PFCs were detected in almost all landfill leachate samples, with concentrations up to 1,020 and 21,300 ng/L, respectively. Mean concentrations were 166 ng/L for PBDEs and 2,950 ng/L for PFCs. Landfill leachates from southern Canada generally had greater concentrations of PBDEs and PFCs than those from northern Canada. The dominant compounds were decabromodiphenyl ether (BDE-209) (mean contribution 52 %) for the PBDEs and perfluorohexanoic acid (mean contribution 25 %) for the PFCs. There were strong correlations for some compounds within each contaminant class, such as the major congeners in the penta-BDE commercial mix (BDE-47, BDE-99, and BDE-100). Estimated average ∑PBDE and ∑PFC loadings from an urban landfill to the environment were calculated to be 3.5 and 62 tonnes/year, respectively.

The effectiveness of a novel and low-cost adsorbent, iron-modified bamboo charcoal (BC-Fe), for arsenic removal from aqueous systems was evaluated in this study. The BC-Fe was synthesized by loading iron onto bamboo charcoal via soaking in a ferric salt solution. The BC-Fe possessed a porous structure with a surface area of 277.895 m2/g. The adsorption characteristics of arsenic onto BC-Fe were further investigated at various pHs, contact times, arsenic concentrations, and adsorbent doses in batch tests. The corresponding optimum equilibrium pH ranges for As(III) and As(V) removal were 4–5 and 3–4, respectively. The equilibrium times for As(III) and As(V) adsorption were 30 and 35.5 h, respectively. The arsenic removal was strongly dependent on the initial adsorbate concentration and adsorbent dosage. The maximum arsenic removal capacities of BC-Fe under the experimental conditions were 7.237 and 19.771 mg/g for As(III) and As(V), respectively. The pseudo-second-order kinetic model and Freundlich isotherm explained the kinetic and equilibrium of both the As(III) and As(V) adsorbent processes, respectively. Based on these results, the BC-Fe developed in this study is a promising material for the treatment of arsenic-contaminated water.

A central wastewater treatment facility was built in 1997 for the town of Suwannee that eliminated 850 inadequately operating on-site sewage treatment and disposal systems. During a study in 1989–1990, Salmonella were detected in Suwannee River water samples upstream and downstream of the town of Suwannee. This study presents the findings of fecal coliform distribution between the years 1996 and 2009 in canals and the main stem of Suwannee River near the town of Suwannee, a coastal area in southeastern USA. Fecal coliforms were measured and assessed to evaluate the water quality before and after the installation of the central wastewater treatment facility. In the canals nearby the town of Suwannee, significant differences in fecal coliform concentrations were detected between the samples collected before and after the operation of the central wastewater treatment facility. Average fecal coliform of 537 most probable number (MPN)/100 ml in the canals in 1996 was reduced to 218 MPN/100 ml after the operation of wastewater treatment facility. The fecal coliform levels in canals decreased significantly in the last 13 years. Even though the average fecal coliform levels in the river was reduced from 170 to 86 MPN/100 ml before and after the installation of the wastewater treatment facility, respectively, the difference was not statistically significant.

Current non-invasive biomonitoring techniques to measure heavy metal exposure in free ranging birds using eggs, feathers and guano are problematic because essential metals copper (Cu) and zinc (Zn) deposited in eggs and feathers are under physiological control, feathers accumulate metals from surface contamination and guano may contain faecal metals of mixed bioavailability. This paper reports a new technique of measuring lead (Pb), Cu and Zn in avian urate spheres (AUS), the solid component of avian urine. These metal levels in AUS (theoretically representing the level of metal taken into the bloodstream, i.e. bioavailable to birds) were compared with levels in eggs (yolk and shell), feathers and whole guano from chickens (Gallus gallus domesticus) exposed to a heavy metal-contaminated soil (an allotment soil containing Pb 555 mg kg⁻¹ dry mass (dm), Cu 273 mg kg⁻¹ dm and Zn 827 mg kg⁻¹ dm). The median metal levels (n = 2) in AUS from chickens exposed to this contaminated soil were Pb 208 μg g⁻¹ uric acid, Cu 66 μg g⁻¹ uric acid and Zn: 526 μg g⁻¹ uric acid. Lead concentrations in egg yolk and shell samples (n = 3) were below the limit of detection (<2 mg kg⁻¹), while Cu and Zn were only consistently detected in the yolk, with median values of 3 and 70 mg kg⁻¹ (dm), respectively, restricting the usefulness of eggs as a biomonitor. Feathers (n = 4) had median Pb, Cu and Zn levels respectively of 15, 10 and 140 mg kg⁻¹ (dm), while whole guano samples (n = 6) were 140, 70 and 230 mg kg⁻¹ (dm). Control samples were collected from another chicken flock; however, because they had no access to soil and their diet was significantly higher in Cu and Zn, no meaningful comparison was possible. Six months after site remediation, by top soil replacement, the exposed chickens had median Pb, Cu and Zn levels respectively in whole guano (n = 6) of 30, 20 and 103 mg kg⁻¹ (dm) and in AUS (n = 4) of 147, 16 and 85 μg g⁻¹ uric acid. We suggest the persistent high Pb level in AUS was a consequence of bone mobilised for egg production, releasing chronically sequestered Pb deposits into the bloodstream. In contrast, AUS levels of Cu and Zn (metals under homeostatic control and sparingly stored) had declined, reflecting the lower current exposure. However because pre- and post-remediation samples were measured using different methods carried out at different laboratories, such comparisons should be guarded. The present study showed that metals can be measured in AUS, but no assessment could be made of availability or uptake to the birds because tissue and blood samples were not concomitantly analysed. A major short coming of the study was the inappropriate control group, having no access to uncontaminated soil and being fed a different diet to the exposed birds. Furthermore guano and urine analysis should have been carried out on samples from individual birds, so biological (rather than just technical) variation of metal levels could have been determined. Future studies into using AUS for biomonitoring environmental heavy metals must resolve such experimental design issues.

The performance of the magnetic anion exchange resin, MIEX®, in the pretreatment of reclaimed water for managed aquifer recharge (MAR) was investigated. MIEX® can effectively remove aromatic organic substances with molecular weights above 10 kDa and between 1 and 5 kDa, which are always present recalcitrant during soil infiltration. The removal of organic substances is accompanied by the elimination of other undesirable components in MAR, such as nitrogen and phosphorus. The optimal process parameters are at resin doses of 5–10 mL L⁻¹ and contact time of 10–15 min, as determined via jar tests. The efficiency of the MAR pilot system was consistent throughout the long running time, during which the MIEX® treatment significantly contributed (30 to 60 %) to the removal of both organic and inorganic materials (i.e., dissolved organic carbon, ultraviolet absorbance at 254 nm, color, nitrate, ammonia, phosphorus, and sulfate). The quality of the MAR final effluent is lower than the groundwater standard for drinking sources (type III in GB/T 14848-93). Based on this study, MIEX® treatment is a suitable and efficient pretreatment method for the removal of extra dissolved organic matters and nitrates in reclaimed water for MAR.

Phosphate removal from water is crucial to the prevention of eutrophication. The phosphate adsorption performance from aqueous solutions by using lanthanum-doped activated carbon fiber (ACF-La) was developed by batch and continuous column adsorption method. The batch sorption condition with respect to interfering ions was tested, and the pseudo second-order and intraparticle diffusion models were used to evaluate the adsorption kinetics of phosphate onto ACF-La in the presence of interfering ions, with the second-order model to fit the experimental data better. Moreover, three factors (phosphate concentration, flow rate, and interfering ions) were examined at column run method to evaluate the practical application of ACF-La to the continuous removal phosphate from solution. Furthermore, how the factors (eluted solution concentration, eluted time, and regeneration number) affect the regeneration efficiency of ACF-La was also investigated. These findings suggest that ACF-La has a considerable potential for the application of phosphate removal from contaminated waters.