Four fluoroquinolone antibiotics (norfloxacin, ciprofloxacin, lomefloxacin, and enrofloxacin) in tap water in Guangzhou and Macao were analyzed using high performance liquid chromatography fluorescence detection. The results showed that all target antibiotics were detected in high rate both in Guangzhou (77.5%) and Macao (100%), ranging from 1.0 to 679.7 ng/L (SD ≤ 37.6) in Guangzhou, and from 2.0 to 37.0 ng/L (SD ≤ 2.5) in Macao. The fluoroquinolone antibiotics pollution in tap water widely distributes in Guangzhou and Macao. In addition, the effect of rainfall on concentration of fluoroquinolone antibiotics in south China was also investigated. Our result indicates that the antibiotic concentration in tap water in Guangzhou tends to obviously reduce at the beginning of rainy season, even decreases below the limit of quantification immediately. Thus, it was clarified that the heavy rain in south China has the function of reducing the fluoroquinolone antibiotics concentrations in tap water.

Earlier studies documented the loss of wood preservatives from new wood. The objective of this study was to evaluate losses from weathered treated wood under field conditions by collecting rainfall leachate from 5 different wood types, all with a surface area of 0.21 m2. Wood samples included weathered chromate copper arsenate (CCA) treated wood at low (2.7 kg/m3), medium (4.8 kg/m3) and high (35.4 kg/m3) retention levels, new alkaline copper quat (ACQ) treated wood (1.1 kg/m3 as CuO) and new untreated wood. Arsenic was found to leach at a higher rate (100 mg in 1 year for low retention) than chromium and copper (<40 mg) in all CCA-treated wood samples. Copper leached at the highest rate from the ACQ sample (670 mg). Overall results suggest that metals' leaching is a continuous process driven by rainfall, and that the mechanism of release from the wood matrix changes as wood weathers.

Evaluation of health impacts arising from inhalation of pollutant particles <10 μm (PM10) is an active research area. However, lack of exposure data at high spatial resolution impedes identification of causal associations between exposure and illness. Biomagnetic monitoring of PM10 deposited on tree leaves may provide a means of obtaining exposure data at high spatial resolution. To calculate ambient PM10 concentrations from leaf magnetic values, the relationship between the magnetic signal and total PM10 mass must be quantified, and the exposure time (via magnetic deposition velocity (MVd) calculations) known. Birches display higher MVd (∼5 cm−1) than lime trees (∼2 cm−1). Leaf saturation remanence values reached ‘equilibrium’ with ambient PM10 concentrations after ∼6 ‘dry’ days (<3 mm/day rainfall). Other co-located species displayed within-species consistency in MVd; robust inter-calibration can thus be achieved, enabling magnetic PM10 biomonitoring at unprecedented spatial resolution.

In urban cities in Southern China, the tissue S/N ratios of epilithic mosses (Haplocladium microphyllum), varied widely from 0.11 to 0.19, are strongly related to some atmospheric chemical parameters (e.g. rainwater SO42−/NH4+ ratios, each people SO2 emission). If tissue S/N ratios in the healthy moss species tend to maintain a constant ratio of 0.15 in unpolluted area, our study cities can be divided into two classes: class I (S/N > 0.15, S excess) and class II (S/N < 0.15, N excess), possibly indicative of stronger industrial activity and higher density of population, respectively. Mosses in all these cities obtained S and N from rainwater at a similar ratio. Sulphur and N isotope ratios in mosses are found significantly linearly correlated with local coal δ34S and NH4+–N wet deposition, respectively, indicating that local coal and animal NH3 are the major atmospheric S and N sources.

Pesticide transport models commonly assume first-order pesticide degradation kinetics for describing reactive transport in soil. This assumption was assessed in mini-column studies with associated batch degradation tests. Soil mini-columns were irrigated with atrazine in two intermittent steps of about 30 days separated by 161 days application of artificial rain water. Atrazine concentration in the effluent peaked to that of the influent concentration after initial break-through but sharply decreased while influx was sustained, suggesting a degradation lag phase. The same pattern was displayed in the second step but peak height and percentage of atrazine recovered in the effluent were lower. A Monod model with biomass decay was successfully calibrated to this data. The model was successfully evaluated against batch degradation data and mini-column experiments at lower flow rate. The study suggested that first-order degradation models may underestimate risk of pesticide leaching if the pesticide degradation potential needs amplification during degradation.

Long term trend analysis of bulk precipitation, throughfall and soil solution elemental fluxes from 12 years monitoring at 10 ICP Level II forest sites in the UK reveal coherent national chemical trends indicating recovery from sulphur deposition and acidification. Soil solution pH increased and sulphate and aluminium decreased at most sites. Trends in nitrogen were variable and dependant on its form. Dissolved organic nitrogen increased in bulk precipitation, throughfall and soil solution at most sites. Nitrate in soil solution declined at sites receiving high nitrogen deposition. Increase in soil dissolved organic carbon was detected - a response to pollution recovery, changes in soil temperature and/or increased microbial activity. An increase of sodium and chloride was evident - a possible result of more frequent storm events at exposed sites. The intensive and integrated nature of monitoring enables the relationships between climate/pollutant exposure and chemical/biological response in forestry to be explored.

To clarify nitrogen (N) sources, the overall N budget in a forested watershed in Kanagawa Prefecture, Central Japan was estimated by measuring dissolved inorganic N (DIN; NH₄ ⁺ + NO₃ ⁻ + NO₂ ⁻) from Nov 2004 through Oct 2005. The estimated N budget (-1.43 kg N ha⁻¹ year⁻¹) showed that the N output rate (stream water N) was higher than the N input rate (bulk deposition N) in the watershed. The annual NO₂ ⁻ and NO₃ ⁻ input rates were 0.02 and 1.99 kg N ha⁻¹ year⁻¹, respectively. NH₄ ⁺ was the predominant source in this forested watershed, accounting for 71% (4.99 kg N ha⁻¹ year⁻¹) of DIN input rate. In addition, this study estimated rainfall pH, air temperature, and wind direction, which were considered as controlling factors related to the atmospheric deposition rate of NH₄ ⁺. This study showed that the rainfall NH₄ ⁺ was inversely proportional to the initial pH of the rainfall, which was calculated by adding the amount of H⁺ consumed by the dissociation process of NH₃₍aq₎ to the measured rainfall pH. This result implies that acid rain can elevate the solubility of NH₃₍g₎ and the dissociation capacity of NH₄ ⁺ throughout the process of precipitation. Also, this study provides strong evidence that the high NH₄ ⁺ deposition rate is mainly derived from NH₃₍g₎ emitted from livestock wastes under the NH₃ transport condition of warm summer and favorable wind direction.

In this work, the determination of moving averages is proposed as a method for quantifying metal, arsenic, and sulfate discharges into a water course undergoing acid mine drainage processes which flows into a public water supply dam in the Iberian Pyrite Belt. The analysis of the results obtained by applying moving averages shows that the highest metal and sulfate concentrations occur in October, coinciding with the first rainfall and the sponging of mine dumps, with November and December being the months when the highest contributions to the Andevalo Dam take place. The discharge of acid mine waters with its corresponding metal load into the Andevalo Dam means, for a single hydrological year, more than 6,000 t of sulfates, almost 600 t of iron, and 1 t of As, of special relevance for the hydrochemical quality of the stored waters. When they arrive at the dam, these metals precipitate, since the water pH is near 7, and remain latent in the bottom sediment as long as the chemical makeup of the dam water does not change.

Occurrence and distribution of three typical endocrine-disrupting chemicals (EDCs), nonylphenol mixture (NPs), bisphenol A (BPA), and 17α-ethynilestradiol (EE2), were investigated in the seawater, suspended solid, and sediment around the coastline of Shenzhen city. Field surveys were conducted in both dry season and rainy season to access the influence of rainfall and basic water quality parameters on the distribution of target EDCs. In the seawater, NPs, BPA, and EE2 ranged from 31 to 1,777 ng/l, from 11 to 777 ng/l, and from 10 to 269 ng/l, respectively. In the suspended solid, NPs, BPA, and EE2 were in the range from 3 to 289 ng/l, from 1 to 75 ng/l, and from 1 to 29 ng/l, respectively. In the sediment, NPs, BPA, and EE2 varied from 9 to 355 ng/g dry weight (dw), from 3 to 156 ng/g dw, and from 7 to 144 ng/g dw, respectively. With the increasing rainfall, the concentrations of target EDCs decreased in seawater and sediment and increased in suspended solid at all the sampling locations. Among the six measured basic water quality parameters, the volatile suspended solid value was positively related with the partition property of target EDCs between suspended solid and seawater. Based on the results of principal component analysis, dissolved organic carbon, total nitrogen, and total phosphorous had close relationships with the distribution of target EDCs in the seawater. Temperature and dissolved oxygen had little relationship with the distribution of target EDCs in the coastal area.

The upper Great Egg Harbor River watershed in New Jersey's Coastal Plain is urbanized but extensive freshwater wetlands are present downstream. In 2006-2007, studies to assess levels of total mercury (THg) found concentrations in unfiltered streamwater to range as high as 187 ng/L in urbanized areas. THg concentrations were <20 ng/L in streamwater in forested/wetlands areas where both THg and dissolved organic carbon concentrations tended to increase while pH and concentrations of dissolved oxygen and nitrate decreased with flushing of soils after rain. Most of the river's flow comes from groundwater seepage; unfiltered groundwater samples contained up to 177 ng/L of THg in urban areas where there is a history of well water with THg that exceeds the drinking water standard (2,000 ng/L). THg concentrations were lower (<25 ng/L) in unfiltered groundwater from downstream wetland areas. In addition to higher THg concentrations (mostly particulate), concentrations of chloride were higher in streamwater and groundwater from urban areas than in those from downstream wetland areas. Methylmercury (MeHg) concentrations in unfiltered streamwater ranged from 0.17 ng/L at a forest/wetlands site to 2.94 ng/L at an urban site. The percentage of THg present as MeHg increased as the percentage of forest + wetlands increased, but also was high in some urban areas. MeHg was detected only in groundwater <1 m below the water/sediment interface. Atmospheric deposition is presumed to be the main source of Hg to the wetlands and also may be a source to groundwater, where wastewater inputs in urban areas are hypothesized to mobilize Hg deposited to soils.