Background, aim, and scope Organoarsenical-containing animal feeds that promote growth and resistance to parasites are mostly excreted unchanged, ending up in nearby wastewater storage lagoons. Earlier work documented the partial transformation of organoarsenicals, such as, 3-nitro-4-hydroxyphenylarsonic acid (roxarsone) to the more toxic inorganic arsenate [As(V)] and 3-amino-4-hydroxyphenylarsonic acid (3-AHPAA). Unidentified roxarsone metabolites using liquid chromatography coupled to inductively coupled plasma mass spectrometry (LC/ICP-MS) were also inferred from the corresponding As mass balance. Earlier batch experiments in our laboratory suggested the presence of organometallic (Cu) complexes during relevant roxarsone degradation experiments. We hypothesized that organocopper compounds were complexed to roxarsone, mediating its degradation in field-collected swine wastewater samples from storage lagoons. The objective of this study was to investigate the role of organometallic (Cu) complexes during roxarsone degradation under aerobic conditions in swine wastewater suspensions, using electrospray ionization mass spectrometry (ES-MS). Materials and methods Two swine wastewater samples differing in % solids content and total recoverable Cu concentrations were reacted with 500 ppb of roxarsone under aerobic conditions for 16 days. LC/ICP-MS and ES-MS were used for As speciation analyses, and characterization of metal-organoarsenical complexes in swine wastewater subsamples, respectively. Results and discussion An organocopper roxarsone metabolite was found only in the high-Cu wastewater sample, suggesting the role of Cu in roxarsone degradation under aerobic conditions. The organocopper metabolite was not found in the low-Cu wastewater sample, because roxarsone did not undergo degradation under aerobic conditions even after 16 days. Conclusions Aerobic degradation of organoarsenicals (roxarsone) has not been documented before. Preliminary dataset from this study illustrates the direct and/or indirect association of particulate Cu in catalyzing roxarsone degradation under aerobic conditions in samples with high % solids content. Recommendations and perspectives Concerns regarding the degradation of roxarsone in wastewater to the more toxic inorganic As may be partially linked to the presence of particulate Cu. The presence of Cu in wastewater-suspended particle surfaces has never been coupled before to organoarsenicals degradation reactions, thus, further studies are needed to elucidate the related reaction mechanisms and pathways. Water depth-dependent solid particle distribution profiles in wastewater storage lagoons could provide empirical evidence towards the design of effective degradation practices for nitrophenol-containing compounds, such as, organoarsenical-containing antibiotics, or explosive munitions compounds.

Background, aim, and scope Concentration monitoring as a basis for risk assessment is a valid approach only if there is an unambiguous relation between concentration and effect. In many cases, no such unambiguous relation exists, since various substances can exert the same effect with differing potencies. If some or all of these substances contributing to a biological effect are unknown, effect-related monitoring becomes indispensable. Endocrine-disrupting substances in water bodies, including the groundwater, are a prominent example of such a case. The aim of the investigations described here was to detect hormonally active substances in the groundwater downstream of obsolete landfills by using the E-screen assay and to possibly assign the biological effect to individual chemical compounds by means of instrumental analyses carried out in parallel. Materials and methods Grab samples of the groundwater were collected downstream from abandoned landfills and prepared by liquid/liquid extraction. The total estrogenic activity in these samples was determined in vitro by applying the E-screen assay. The human breast cancer cells (MCF-7) used in the E-screen proliferate in response to the presence of estrogenically active compounds. Expressed in concentration units of the reference substance 17β-estradiol (E2), the test system allows the quantification of estrogenicity with a limit of detection (LOD) in the range of 0.1 ng/L. Aliquots of the samples were screened using gas chromatography/mass spectrometry (GC/MS) in order to quantify known estrogenically active substances and to identify unknown compounds. Estrogen-positive samples were extracted at different pH values, split into acidic, neutral, and basic fractions and analyzed by GC/MS, searching for individual components that display estrogenic activity. Results and discussion Estrogenic activity exceeding the LOD and the provisional benchmark of 0.5 ng E2/L was found at three out of seven abandoned waste disposal sites tested. The low concentrations of known xenoestrogens such as bisphenol-A, nonylphenols, or phthalic acid esters determined by GC/MS, however, were not sufficient to explain the detected activity. Neither natural nor synthetic hormones have caused the activity because these chemical structures are readily degradable and cannot persist in abandoned landfills for decades. The highest activity in the E-screen assay was found in the acidic fractions. Hydroxy-polychlorinated biphenyls (PCBs), hydroxylated polycyclic aromatic hydrocarbons (PAHs) and hetero-PAHs, as well as alkylphenols could be identified as further compounds with possible hormonal activity. Conclusions Estrogenically active substances may occur in the groundwater below obsolete landfills, especially those that contain PCBs or waste from gasworks. These substances are not part of analytical programs routinely applied to contaminated sites and may therefore escape detection and assessment. Analyses using the E-screen assay and GC/MS in parallel have shown that the total estrogenic activity found in groundwater samples is to be ascribed to a multitude of individual compounds, some of which cannot be quantified due to lack of standard substances or assessed due to lack of a standardized procedure for determination of their estrogenic potency. By comparison with provisional guide values for estradiol (0.5 ng/L) and ethynylestradiol (0.3 ng/L), the damaging potential of the total estrogenic activity in groundwater samples can in fact be assessed, but specific remediation measures are impossible unless the hormonal activity can be attributed to individual chemical substances. Recommendations and outlook On the one hand, further analyses of samples taken from possible pollution sources should be conducted in order to characterize the extent of groundwater pollution with xenoestrogens. On the other hand, the most potent individual compounds should be identified according to their estrogenic potency. To this end, bioassay-directed fractionation and structure elucidation should be carried out with concentrated samples.

Purpose The environmental issues caused by the municipal solid waste disposal are becoming a worldwide concern. Methods We studied the situations both domestically and abroad by the strategic environmental assessment (SEA) approach and also conducted comprehensive evaluations of garbage disposal in Changchun City. Results On the basis of this study, we found that SEA is of great importance in the municipal solid waste disposal. Moreover, with the rapid socioeconomic development of Changchun City, municipal solid waste production increases on an annual basis, and thus, good waste management planning is of great significance. Conclusions Considering the situation of the economic development of Changchun City, garbage disposal was handled mainly in the major sanitary landfills with appropriate use of incineration technology. This plan is environmentally friendly at a relatively high degree and has met the requirements of minimum investment. It also takes into account the requirements of the development of incineration technology. Regarding environmental pollution in terms of groundwater pollution and atmospheric pollution, this plan is a feasible one by meeting various requirements with low environmental impact among the three plans discussed in this study.

INTRODUCTION: In this work, we propose an innovative application of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) as a methodological approach for the chemical characterisation of black crusts on stone monuments, associated with traditional micro-morphological (optical and scanning electron microscopy) and infrared spectroscopic techniques (FTIR). METHODS: This new approach was tested on black crusts developing on two marble substrates, one, the columns of the San Cosimato cloister in Rome, and the other, a sculpture representing an angel, located in Pessano con Bornago, a small industrial town near Milan. DISCUSSION: The main aim of this study was to develop and test the reliability of the LA-ICP-MS analytical method on black crusts and to explore the idea that trace element concentrations in black crusts can be applied to investigate their origin and the relations between concentrations of polluting elements in black crusts and environmental conditions. CONCLUSION: The results obtained by applying traditional techniques find considerable support in the innovative method used here, which could determine the concentrations of a large number of trace elements (including heavy metals) in the black crusts examined, and thus could also be used as a reliable indicator of environmental pollution.

Background, aim, and scope To stimulate the national economy, a so-called “gold week” comprising May Day and National Day has been put in force by the government, and the first golden-week holiday began on October 1, 1999. Statistical data show that about 15,000 visitors were received each day by Emperor Qin's Terra-Cotta Museum during just such a gold week period. To evaluate the effects of tourism on indoor air, airborne samples were collected by the sedimentation plate method for 5 min during the “Oct. 1” gold week period of 2006, and both composition and changes of airborne bacteria and fungi in indoor/outdoor air in the museums were investigated. Materials and methods Airborne microbes were simultaneously collected by means of gravitational sedimentation on open Petri dishes. Three parallel samples were collected at the same time each day, and samples were subsequently incubated in the lab. Microbiology media were prepared before each experiment by a professional laboratory. Concentrations were calculated and presented as average data of colony-forming units per cubic meter of air (CFU/m³). Results The results show that (1) 13 bacterial genera and eight genera of fungi were identified from indoor and outdoor air at Emperor Qin's Terra-Cotta Museum during “Oct. 1” gold week in 2006. The bacterial groups occupied 61%, the fungi groups occupied 36%, and others occupied 3% of the total number of isolated microorganism genera. (2) As for the comparison of indoor and outdoor samples, the average concentrations of fungi were higher during the afternoon (13:00) than for the morning (09:00). The average concentrations of bacteria in indoor air were higher during the afternoon (13:00) than for the morning (9:00), and in outdoor air, they were lower during the afternoon (13:00) than for the morning (9:00). (3) The average concentrations of five dominant groups of bacteria and three dominant groups of fungi were higher during the afternoon (13:00) than for the morning (9:00) in the indoor air, but the average concentrations of fungi were higher and those of bacteria were lower during the afternoon than for the morning, for outdoor air. (4) As for the comparison of indoor samples, the bacterial daily concentrations and fungal daily concentrations were higher during the afternoon (13:00) than those for the mornings (9:00) over the 10 days. For the comparison of outdoor samples, the bacterial concentration was lower, and the fungal concentrations were higher during the afternoon (13:00) than those for the morning (9:00) over the 10 days. Discussion The results also show that the numbers of airborne bacteria and fungi had a daily character in indoor air and were higher in the afternoon. The airborne microbe concentrations were found to be similar to residential indoor values from other reports; the indoor museum maximum of microbial concentrations was 90 CFU/m³ and did not exceed the Chinese indoor bioaerosol guideline. However, microorganisms may fall on the surface of display items as a result of particle sedimentation and would, as such, be capable of degrading objects by way of their secretions, e.g., enzymes and organic acids. Therefore, the right steps should be taken to prevent any deterioration in the quality of displayed artifacts. Conclusions The results show that museum air was affected by human activity; therefore, it is imperative that the number of visitors be strictly limited and that windows be opened regularly to avoid air pollution. Recommendations and perspectives The data provide a significant scientific basis for indoor air quality control and museum scientific management. It is recommended that the number of visitors be strictly limited.

Purposes Very few data for polybrominated diphenyl ethers (PBDEs) were available in the Yangtze River Delta (YRD), one of the most developed and urbanized region in China. In this study, Chongming Island, located at the estuary of the Yangtze River, was selected as background area to investigate the occurrence, sources, and inventory of PBDEs. Methods Forty-two PBDE congeners were determined in surface soils from farmland, woodland, grassland, tideland, and road collected in Chongming Island. Results The mean concentrations of Σ₂₆PBDE (not including BDE-209) and BDE-209 in soils were 0.76 and 12 ng/g dry weight, respectively. BDE-209 contributed more than 90% of the total of 27 frequently detected BDE congeners, followed by BDE-99 and BDE-47. Weak correlations were found between total organic carbon content and PBDE congeners concentrations in surface soils. PBDE levels varied with land use. Farmland and woodland soils contained higher Σ₂₆PBDE concentrations. BDE-209 levels were the highest in road soils. The mass inventories of PBDEs in soils of Chongming Island were estimated at 3.1 and 310 kg for Σ₂₆PBDEs and BDE-209, respectively. Conclusions The PBDE levels in Chongming Island were similar to those in European background soils, suggesting minimum influence of pollutants from the YRD via air, and wastewater inputs or few PBDE products were used herein. From the standpoint of eco-inland, more studies are needed to explore the reasons of PBDE difference by land use and to assess people intake PBDEs via agriculture products consumption in this region.

Purpose China's freshwater subtropical shallow lakes are increasingly eutrophic and susceptible to production of heavy growths or water blooms of cyanobacteria. One example was the heavy water bloom that occurred for the first time in Lake Xuanwu, in 2005, an urban lake located in Nanjing city. The aim of the present study was to determine dynamics of water bloom dominating Microcystis in this lake. Meanwhile, the relationship between environmental factors and Microcystis populations was also analyzed. Materials and methods Molecular detection, using quantitative polymerase chain reaction, was used in this lake to study the dynamics of the cyanobacterial community, its Microcystis populations, and the microcystin-producing Microcystis genotypes from August 2005 to November 2006. Results It was shown that Microcystis wesenbergii and Microcystis aeruginosa were the main components of the cyanobacterial blooms in Lake Xuanwu, and they coexisted with species of the filamentous cyanobacterial genera Anabaena, Planktothrix, and Anabaenopsis. Microcystis cells were detected during the entire survey period and in all sample sites. The cell abundance of Microcystis ranged from 3.6 × 10² cells ml⁻¹ to a peak of 3.8 × 10⁶ cells ml⁻¹. The ratio of mcyB-containing Microcystis subpopulations to the total Microcystis varied, ranging from 0.1% to 12.8%. The abundance of Microcystis containing the mcyB microcystin gene was shown to be significantly correlated with concentrations of total phosphorus and phosphate. Conclusions Water temperature was the primary factor affecting Microcystis abundance in the lake, and phosphorus loading was shown to be a main factor in governing the growth of both microcystin-producing genotype and total Microcystis population. Higher Microcystis cell counts at the bottom of the water column before and after appearance of water blooms in Lake Xuanwu suggested that Microcystis numbers in the water column, especially at the bottom of the water column, play an important role in forming the next water bloom.

Background, aim, and scope Impacts on the reproductive health of wild fish are thought to be suitable early-warning tools indicating contamination of surface waters with endocrine-disrupting compounds. Ecotoxicological assessment of these field observations depends on the availability of reliable biomarkers to enable a discrimination of natural variations of reproductive functions from anthropogenic impacts. Materials and methods Roach and perch were caught at eight sampling sites by electrofishing twice a year in summer (July-September) and late autumn/winter (November-December) over a 2-year period. The sites are characterized by different degrees of anthropogenic impact and are situated within the greater Upper Rhine catchment. Age growths, parasitization and gonadal histology of more than 3,000 fish were examined. Results The two dominant fish species in German surface waters perch (Perca fluviatilis L.) and roach (Rutilus rutilus L.) differ considerably regarding their suitability for biomonitoring. Even in pristine habitats, perch show several variants of sex differentiation in terms of (1) the time of first sexual maturation, (2) the course of seasonal gonadal recrudescence, and (3) the occurrence of heterologous germ cells (testes ova). A statistically significant elevated proportion of males were observed in fish obtained from a TBT-contaminated marina and suppression of gonadal ripening was observed in females caught in a sewage-contaminated brook. Both effects appear to be due to chemical contamination. The only “natural” alteration of sex differentiation in roach was related to parasitization with Ligula intestinalis (Eucestoda, Pseudophyllidea). Other deviations from the normal pattern of sex differentiation were (1) suppression of ovarian ripening and (2) asynchronic seasonal gonadal recrudescence. These are strong indicators of an anthropogenically induced impact on reproductive health. Feminization phenomena were not observed at either the individual or the population level. Discussion Interpretation of field monitoring results concerning reproductive health requires large numbers of samples and detailed knowledge of the natural plasticity of sex differentiation in the species under investigation. A better understanding of the mechanisms underlying the plasticity of sex differentiation in perch is indispensable to enable perch to be used as a bioindicator. Conclusions Deviation from the strict and probably endogenous control of sex differentiation in roach is a strong and unequivocal warning signal. Recommendations and perspectives The subject of fish monitoring should be addressed in the context of a broader spectrum of potential risks. Seasonal and ontogenetic integrity of gonadal development and recrudescence are potent biomarkers, provided the natural process is well documented for the species under investigation.

Background, aim, and scope Soil contamination with heavy metals occurs as a result of both anthropogenic and natural activities. Heavy metals could have long-term hazardous impacts on the health of soil ecosystems and adverse influences on soil biological processes. Soil enzymatic activities are recognized as sensors towards any natural and anthropogenic disturbance occurring in the soil ecosystem. Similarly, microbial biomass carbon (MBC) is also considered as one of the important soil biological activities frequently influenced by heavy metal contamination. The polymerase chain reaction-denaturing gradient gel electrophoresis (DGGE) has recently been used to investigate changes in soil microbial community composition in response to environmental stresses. Soil microbial community structure and activities are difficult to elucidate using single monitoring approach; therefore, for a better insight and complete depiction of the soil microbial situation, different approaches need to be used. This study was conducted in a greenhouse for a period of 12 weeks to evaluate the changes in indigenous microbial community structure and activities in the soil amended with different application rates of Cd, Pb, and Cd/Pb mix. In a field environment, soil is contaminated with single or mixed heavy metals; so that, in this research, we used the selected metals in both single and mixed forms at different application rates and investigated their toxic effects on microbial community structure and activities, using soil enzyme assays, plate counting, and advanced molecular DGGE technique. Soil microbial activities, including acid phosphatase (ACP), urease (URE), and MBC, and microbial community structure were studied. Materials and methods A soil sample (0-20 cm) with an unknown history of heavy metal contamination was collected and amended with Cd, Pb, and Cd/Pb mix using the CdSO₄ and Pb(NO₃)₂ solutions at different application rates. The amended soils were incubated in the greenhouse at 25 ± 4°C and 60% water-holding capacity for 12 weeks. During the incubation period, samples were collected from each pot at 0, 2, 9, and 12 weeks for enzyme assays, MBC, numeration of microbes, and DNA extraction. Fumigation-extraction method was used to measure the MBC, while plate counting techniques were used to numerate viable heterotrophic bacteria, fungi, and actinomycetes. Soil DNAs were extracted from the samples and used for DGGE analysis. Results ACP, URE, and MBC activities of microbial community were significantly lower (p < 0.05) in the metal-amended samples than those in the control. The enzyme inhibition extent was obvious between different incubation periods and varied as the incubation proceeded, and the highest rate was detected in the samples after 2 weeks. However, the lowest values of ACP and URE activities (35.6% and 36.6% of the control, respectively) were found in the Cd₃/Pb₃-treated sample after 2 weeks. Similarly, MBC was strongly decreased in both Cd/Pb-amended samples and highest reduction (52.4%) was detected for Cd₃/Pb₃ treatment. The number of bacteria and actinomycetes were significantly decreased in the heavy metal-amended samples compared to the control, while fungal cells were not significantly different (from 2.3% to 23.87%). In this study, the DGGE profile indicated that the high dose of metal amendment caused a greater change in the number of bands. DGGE banding patterns confirmed that the addition of metals had a significant impact on microbial community structure. Discussion In soil ecosystem, heavy metals exhibit toxicological effects on soil microbes which may lead to the decrease of their numbers and activities. This study demonstrated that toxicological effects of heavy metals on soil microbial community structure and activities depend largely on the type and concentration of metal and incubation time. The inhibition extent varied widely among different incubation periods for these enzymes. Furthermore, the rapid inhibition in microbial activities such as ACP, URE, and MBC were observed in the 2 weeks, which should be related to the fact that the microbes were suddenly exposed to heavy metals. The increased inhibition of soil microbial activities is likely to be related to tolerance and adaptation of the microbial community, concentration of pollutants, and mechanisms of heavy metals. The DGGE profile has shown that the structure of the bacterial community changed in amended heavy metal samples. In this research, the microbial community structure was highly affected, consistent with the lower microbial activities in different levels of heavy metals. Furthermore, a great community change in this study, particularly at a high level of contamination, was probably a result of metal toxicity and also unavailability of nutrients because no nutrients were supplied during the whole incubation period. Conclusions The added concentrations of heavy metals have changed the soil microbial community structure and activities. The highest inhibitory effects on soil microbial activities were observed at 2 weeks of incubation. The bacteria were more sensitive than actinomycetes and fungi. The DGGE profile indicated that bacterial community structure was changed in the Cd/Pb-amended samples, particularly at high concentrations. Recommendations and perspectives The investigation of soil microbial community structure and activities together could give more reliable and accurate information about the toxic effects of heavy metals on soil health.

Background, aim, and scope The Lower Mississippi River is a major transportation route for commercial goods and petroleum products produced and refined locally. Oil spills caused by vessel accidents and equipment failure at refineries are a serious threat to the drinking water supply of Southern Louisiana, as well as to the many natural, economic, and social resources supported by the river. Providing accurate trajectory modeling to contingency planners is critical to protecting the local environment. The majority of trajectory model results, assuming a uniform shoreline, show 60-70% of spilled oil can be retained. This study examines the impact of detailed shoreline mapping that captures spatial and temporal changes in shoreline type on oil spill trajectory modeling. Materials and methods Detailed shoreline maps based on recent remote sensing imagery were generated to identify spatial changes in shoreline. A hydrodynamic model of the 78 mile reach from Convent, Louisiana to West Pointe a la Hache was developed to obtain the stage levels and velocity fields of four river discharges. Based on river stage level, another layer was added to the shoreline maps, so that shoreline type was accurately represented at each river discharge, a feature not included in previous mapping. An oil spill trajectory model was then used to investigate the effect of implementing different re-floatation half-lives that correlate to the shoreline maps developed for this study at four river discharges. Results Detailed shoreline mapping showed the Lower Mississippi River has four major shoreline types each with different oil re-floatation half-lives: muddy clay, sand, low vegetation, and high vegetation. As flow rate changed, the shoreline spatial variability also changed, from 84% mud/sand and 16% vegetation at low flow rates to 4% mud and 96% vegetation at higher flow rates. At flow rates with large variability in shoreline type, the distribution of oil attached to the shore was significantly different from results of simulations that used a constant shoreline type and re-floatation half-life. Discussion At low flow rates, simulations with the detailed delineation of shoreline type predicted that ~30% of the oil would be beached/retained because the oil was able to travel further down the reach and interact with the shoreline in multiple locations. Simulations at the low flow rates with the existing shoreline mapping predicted approximately 65% of the oil would be retained as did all the simulations at the highest flow rates. At high flow rates, the oil interacted mostly with vegetation and results were very similar to those obtained with a single re-floatation half-life of 1 year. In addition to shoreline type, river geometry and the hydrodynamics were major factors influencing the distribution of oil along the river reach. Conclusions Shoreline re-floatation half-lives have a major impact on simulating the distribution of oil along the shore after a spill, especially in areas with a high variability of shoreline type as in the lower Mississippi River. Assigning the correct re-floatation half-life and retention capacity is only possible when shoreline types have been correctly identified. The maps developed for this study provided an important level of detail and incorporated the change in shoreline type with flow rate, resulting in more detailed trajectory modeling of the study reach. Recommendations and perspectives Shoreline maps should include as much detail about shoreline type as possible. When developing shoreline maps or environmental sensitivity assessments, the focus should include specific characteristics of the study area; using standardized maps or methods of assessment may leave out detail that could negatively impact modeling efforts. Finally, shoreline sensitivity to oiling is an important area of research that will benefit from an improved understanding of oil retention by vegetation.