Contamination of the Coastal Waters of Gijón (North West Spain) by Butyltin Compounds

An innovative method for the determination of butyltin compounds in seawater samples based on the use of isotope dilution analysis has been applied to study the contamination of butyltin compounds in the Bay of Gijón (Spain) where no previous data existed. The sampling in this bay allowed the evaluation of mono-, di-and tributyltin (MBT, DBT and TBT, respectively) contamination in very different environmental compartments (harbour, marina, shipyards and enclosed and open beaches). The results showed clearly a strong influence of the type of location, the water renewal and the proximity to contaminated areas on the levels of butyltin compounds. It was found that in more than 75% of the samples the TBT values were found to be higher than the US-EPA water quality criteria of 7.4 ng L^?1 and that in 95% of the samples the concentration of TBT exceeded 1 ng L^?1 which has been reported to be a toxic level for many marine species.     

Occurrence of Organotin Compounds in the Aquatic Environment of Greece

The presence of organotin (OT) compounds was investigated in coastal areas (10 stations), wastewater treatment systems (six stations), rivers (19 stations) and lakes (12 stations) throughout Greece, in three sampling campaigns organized between October 1998 and September 1999. A screening method for the determination of toluene extractable organotins (TEOTs) by Electrothermal Atomic Absorption Spectrometry (ETAAS) was used during the first two sampling campaigns. TEOTs (sum of tributyltin, TBT, dibutyltin, DBT and triphenyltin, TPhT) were detected in most seawater and wastewater samples at concentrations up to 19.4 and 89.9 ng l^?1, respectively, while they were detected occasionally in surface water. During the third sampling campaign, OT compounds were extracted in selected stations using direct derivatization with NaBEt₄ in acidic medium and analysed by Gas Chromatography–Mass Spectrometry (GC–MS). In seawater, the levels of TBT, DBT and monobutyltin (MBT) were varied between < 2 and 70, 159 and 19 ng l^?1, respectively and tend to decrease with increasing distance from the coastline. TPhT was not detected in any of the samples. Significant concentrations of OT species were detected in influent wastewater, up to 384, 76.2 and 67.8 ng l^?1 for TBT, DBT and MBT, respectively. OTs were mainly associated with the suspended solids and were totally removed during wastewater treatment.     

A Survey of Organotin Compounds in the Northern Adriatic Sea

The extent of pollution with organotin compounds was investigated in water, sediment and bivalve mussels (Mytilus galloprovincialis) from the Northern Adriatic Sea. Butyl-, phenyl- and octyltin species were quantified after extraction and derivatisation by gas chromatography–mass spectrometry in a total of 99 samples from the period from 2000 to 2006. The accuracies of the analytical procedures were checked by spiking of unpolluted water samples and by the analysis of standard reference materials (harbour sediment PACS-2 and mussel tissue ERM-CE 477). Among organotin species analysed in samples butyltins were the predominant. Tributyltin was found to be present in the highest concentrations, suggesting its recent input into the marine environment. Butyltins were detected at all sites surveyed (sum of butyltins was up to 718 ng Sn L^?1, 3,552 ng Sn g^?1 d.w. and 9,991 ng Sn g^?1 d.w. in water, sediment and mussel samples, respectively), phenytins in much lower concentrations (up to 31 ng Sn L^?1, 326 ng Sn g^?1 d.w. and 442 ng Sn g^?1 d.w. in water, sediment and mussel samples) and to a much smaller extent, while octyltins were not detected at any location. The spatial distribution of tributyltin was closely related to boating, with the highest concentrations found in marinas (up to 586 ng Sn L^?1 for water samples, 1,995 ng Sn g^?1 d.w. for sediment and 6,434 ng Sn g^?1 d.w. for mussel samples). The temporal distribution clearly indicates a decrease of organotin pollution at all sites.     

Modelling of Pore Water Nutrient Distribution and Benthic Fluxes in Shallow Coastal Waters (Gulf of Trieste, Northern Adriatic)

Pore waters, extracted monthly from short cores at two sedimentologically and biologically different locations (AA1 and F) in the Gulf of Trieste (Northern Adriatic), were analyzed for NH₄ ⁺, NO₃ ⁺, PO₄ ³⁺, Si(OH)₄, DIC and periodically for DOC, DON and DOP. Nutrient concentrations were used to model vertical profiles using a diffusion-reaction model which included the macrofaunal influence on sediment-water exchange rates. Winter nutrient profiles showed nearly an exponential increase, or decrease in the case of NO₃ ⁺, in nutrient concentrations with depth while the profiles from other seasons exhibited concentration maximum at 3–6 cm, a minimum around 8–10 cm, and then, except for NO₃ ⁺, a gradual increase or constant values. This vertical distribution is attributed to seasonal variations in the benthic infauna activity, mostly composed of polychaetes and bivalves and concentrated in the top 4–5 cm, being less active during the winter. The vertical profiles of DOC and DON showed the vertical distribution described above in all periods, while DOP was similar to that of PO₄ ³. The comparison of modelled fluxes of nutrients across the sediment-water interface at the location AA1 and those measured usingin situ benthic chamber showed quite good agreement for NH₄ ⁺ and PO₄ ³, fluxes but not for NO, and Si(OH)₄. Discrepancies could be caused by a topography effect and for Si(OH)₄ by an additional dissolution of the solid phase balancing the diffusive loss into burrows and lessening the effect of bioturbation.     

Fate and Transport of Organic Compounds in Municipal Solid Waste Compost

Four chemicals, polychlorinated biphenyls (PCB), benzo(a)pyrene (B(a)P), a-chlordane, and bisethylhexyl phthalate (BEHP), were chosen for investigation because of their range of physical/chemical properties and because they have been reported in municipal solid waste compost in the literature. Field studies were performed by applying amended compost, which was spiked with the four chosen organic chemicals, into corn, fescue, and poplar fields in Amana, Iowa.

The Pesticide Root Zone Model II (PRZM II), a U.S. EPA computer code (Dean, et al., 1989), was utilized to predict the potential fate and transport of four chemicals in the unsaturated zone. Model input consisted of meteorological records from nearby weather stations, soil data from the Amana site and laboratory results/literature values of chemical properties.

Results indicate that, due to their relatively low solubility and high hydrophobicity, the chemicals are quite sorptive to the soil/compost mixture and barely migrate vertically in the soil. In five year simulations, the chemicals remained within the rooting zone of the plants and slowly biodegraded. Plant uptakes were relatively small and essentially no leachate reached the groundwater table. Volatilization of PCB and chlordane was significant only for the top soil layer. A field study is being used to verify the modeling results.     

Organotin Compounds in Sediments from the Göta älv Estuary

Concentrations of organotin compounds in sediments from four sites in the Göta älv estuary, SW Sweden, rangefrom 17 to 366 ng/g dw for tributyltin (TBT) and from1.5 to 71 ng/g dw for triphenyltin (TPT), similar toresults from other harbours and marinas and from an earlier study in the Göteborg Harbour, which is located in the estuary. Also dibutyltin, monobutyltin, diphenyltin and monophenyltin, the degradation products of TBT and TPT, werefound. TBT concentrations are the highest in the inner harbour and in the upper sediment layer of ca. 10 cm, indicating the risk for mobilisation of TBT bound in surface sediments in thefrequently disturbed harbour environment.     

Biochemistry of TBT-Degrading Marine Pseudomonads Isolated from Indian Coastal Waters

Tributyltin (TBT) is a very effective biocide and an active ingredient in antifouling paints. Screening along the Indian coast yielded 49 bacterial isolates capable of TBT assimilation. The screening was done based on the ability of bacteria to grow in mineral salt medium (MSM) containing TBT as the sole source of carbon. All the isolates produced exopolysaccharides (biosurfactants) in the medium which aid in emulsification and thus ease bioavailability of TBT. Five isolates were identified as potent TBT degraders (namely, Pseudomonas pseudoalcaligenes, Pseudomonas stutzeri, Pseudomonas mendocina, Pseudomonas putida, and Pseudomonas balearica) based on their biomass production in MSM containing TBT as the sole source of carbon. In addition to evaluating the potential of individual bacterial strains, the study also focused on using a consortium of bacteria to explore their synergistic effect when grown on TBT. Further tests like growth profile, rhamnolipid secretion profile, extracellular protein secretion profile, and detection of siderophores were performed on these isolates when grown in MSM supplemented with 2 mM TBT concentration. Emulsification activity of the crude extracellular polysaccharides against kerosene was evaluated. It can be therefore inferred that TBT degradation by these marine pseudomonads is a two-step process: (a) dispersion of TBT in the aqueous phase and (b) tin–carbon bond cleavage by siderophores affecting debutylation of TBT. The consortium of bacteria may be effective in the treatment of TBT-contaminated waste water in dry docks.     

Levels and Distribution of Petroleum Hydrocarbons in the Coastal Waters and Sediments of the United Arab Emirates in the Arabian Gulf and the Gulf of Oman

The levels and distributions of petroleum hydrocarbons incoastal waters and sediments of the United Arab Emirates (U. A. E.) along theArabian Gulf and the Gulf of Oman were investigated. Oil concentrations in the waters ofthe U. A. E. were below the 15 μg L^-1 and ranged from 1.6 to 13 μg L^-1.Petroleum hydrocarbons showed different pattern of distribution in the Arabian Gulf and the Gulf of Oman withmore or less similar values. Horizontal distribution of petroleum hydrocarbons atthe Arabian Gulf showed significant differences between most sites. At the Gulf ofOman, similar oil concentrations were measured at different sites. Meanwhile,vertical distributions of petroleum hydrocarbons indicated higher concentrations atsurface layers of the Arabian Gulf compared to bottom layers. Whereas, more or less similarconcentrations were measured at the Gulf of Oman. The concentration of petroleum hydrocarbons in marinesediments varied from 2.5 to 8.2 μg g^-1 (dry sediment weight), with higher concentrations at theArabian Gulf compared to the Gulf of Oman. The pattern of distribution for petroleumhydrocarbons in marine sediments resembled to some extent the distribution of organiccarbon in marine sediments. The study revealed that the concentrations ofpetroleum hydrocarbons in waters and sediments of the investigated area are not highcompared to other areas of the world.     

Occurrence of Organotin Compounds in Water, Sediments and Mollusca in Estuarine Systems in the Southwest of Spain

Six organotin species – tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT), triphenyltin (TPT), diphenyltin (DPT) andmonophenyltin (MPT) – have been determined in seawater (255 samples), sediments (85 samples) and bivalves (558 samples) collected at seventeen locations in the southwest of Spain in five occasions between May 1992 and August 1994. No phenyltinspecies were found but butyltin species were present in all the stations. The TBT concentrations ranged between 23 and 1500 ng g^-1 Sn in biota, from less than 0.6 to 160 ng g^-1 Sn in sediments and from less than 0.5 to 31 ng L^-1 Sn in water, with the highest values closely related with boating activity and decreasing according to the distance from the potential sources. For biota and water, a consistent seasonal pattern of fluctuation of TBT concentrations was evident, with the highest values found in spring and summer except for a fishing harbour. A slow decreaseof TBT concentration was observed between 1992 and 1994. Percentages of DBT and MBT in biota (22±7 and 13±6,respectively) were lower than those in water (33±10 and 31±15, respectively) and sediments (48±16 and 25±16, respectively). Sediment-water partition coefficients for TBT were 240–65 000 and bioconcentration factors 17 000–350 000. This article discusses the significance of the pollution in our study area in comparison with other world coastal areas.     

Quantifying Water Retention Time in Non-tidal Coastal Waters Using Statistical and Mass Balance Models

Elements uptake, histological distributions as well as mycorrhizal and physiological statuses of Atriplex halimus were determined on trace metal and metalloid polluted soils from the surrounding spray zones of a former lead smelter in the South-East coast of Marseille (France). Analyses of heavy metal and arsenic distribution in soil and plant organs showed that A. halimus tolerance is largely due to exclusion mechanisms. No specific heavy metal concentration in leaf or root tissues was observed. However, accumulation of salts (NaCl, KCl, Mg and Ca salts) on leaf bladders and peripheral tissues of roots was observed and may compete with metal element absorption. Occurrence of endomycorrhizal structures was detected in roots and may contribute to lower element transfer from root into the aerial parts of plants. The non-destructive measurements of leaf epidermal chlorophylls, flavonols and phenols showed a healthy state of the A. halimus population on the metal and metalloid polluted sites. Considering the low metal bioaccumulation and translocation factors along with a reduced metal stress diagnosis, A. halimus appeared as a good candidate for phytostabilization of trace metals and metalloids and notably arsenic in contaminated soils of the Mediterranean spray zone. However, its invasive potential has to be determined before an intensive in situ use.     

Possibility of Reductive Deactivation of S-Triazines and Parent Compounds on Waters and Sediments

Electrochemistry can be a valuable instrument to preserve the aquatic environment, first, by elucidating the oxidation-reduction mechanisms of substances having toxicological potential at laboratory scale; second, by aiding through extrapolation to comprise the evolution and fate in the environment of these pollutants and, finally, by establishing the basis of some electrochemical deactivation processes at industrial scale. In this way, this paper deals on studies of a type of highly pollutant substances for the aquatic media such as the S-triazines. The first part of the paper is focused to show the electrochemical reduction behavior of some S-triazines (eleven compounds have been studied). Later, the probable consequences at natural scale of these electroreductive processes are evaluated. Thus, the electrochemical reduction of diluted solutions of s-triazine herbicides and parent compounds takes place at potentials of ?0.90 to ?1.20 V, at very acidic pH values. The electroreduction products generated in all cases have loss the aromaticity and, depending on the compound, the chlorine atom or the –SCH₃ group. So, the resulting molecules present lower toxicity than the original compounds. For this reason, the electroreductive way can be an efficient option for the detoxification of S-triazine polluted waters. On the other hand, the natural deactivation of the s-triazines present in natural waters, in addition to the conventional photooxidative route taking place in well illuminated and oxygenated waters, could take place through the reductive process when the waters are essentially anoxic, acidic, and rich in suspended materials. This natural reduction, moreover, could favour the later oxidation or metabolization of the byproducts emanating of the original plaguicides. Finally, the reduction of S-triazines, both forced (industrial water depuration via electrochemical reduction) and no forced (natural aquatic media) requires more negative redox potentials, that is, more reductive environments as the molecules become more complex.     

Evaluation of Water Quality Impacts of On-site Treatment and Disposal Systems on Urban Coastal Waters

Questions have been raised about the impact of onsite sewage treatment and disposal systems (OSTDS) on adjacent water bodies, particularly in coastal areas. If OSTDS are not properly sited and maintained, they pose a potential risk to public health and may contribute toward degradation of the receiving water body. To quantify the pollutant loading contributions from OSTDS located adjacent to coastal canals, two similar single-family residential neighborhoods were evaluated. One was connected to the sanitary sewer network (Hollywood, FL) and the other was served exclusively by septic tanks (Dania Beach, FL). Water quality sampling, focusing on nutrient and pathogen indicators, was conducted at the paired sites during the seasonal high water table (SHWT) and seasonal low water table (SLWT) events. During the SHWT, measured canal water quality, in terms of nutrient (i.e. nitrate) and microbial pathogen indicators in the adjacent areas appeared to be impacted by OSTDS. However, during the SLWT, no obvious impacts attributable to the septic tanks were detected. This suggests that the OSTDS may operate properly when the water table is low, but that the contributions by OSTDS to coastal pollutant loading may be quantifiable during certain portions of the calendar year when the ground water table elevation is relatively high, although the impact on the downstream marine environment is uncertain as a result of tidal dilution and lack of offshore study.     

海南岛沿岸牡蛎体内六六六的时空变化特征分析及风险评价

于2006—2011年间每年的3月份,在海南岛沿岸选取的4个重要港湾（马袅港、东寨港、八所港、榆林港）采集近江牡蛎（Crassostrea rivularis Gould）成体30只,用气相色谱法测定其六六六（HCHs,包括α-、β-、γ-、δ-HCH）含量。结果显示,2006—2011年近江牡蛎体中HCHs含量范围是未检出～1.16 ng.g-1,平均含量是0.15 ng·g-1,与1985年海南岛贝类体内的HCHs残留量相比,20多年间浓度降低至原来的1/45。在这6年中HCHs含量于2006—2008年先略微下降,之后小范围上下波动,但总体上呈平稳的趋势;样品中HCHs区域平均含量由高到低依次为马袅港〉东寨港〉八所港〉榆林港。通过对HCHs的组分特征分析,认为海南岛采样海域周围近年没有新的HCHs污染源输入。与世界其他海域贝类体内HCHs含量比较,海南岛沿岸牡蛎体内HCHs残留量较低,符合中国《海洋生物质量》一类质量标准。通过计算安全消费量,认为海南岛沿岸海域牡蛎体内HCHs致癌风险和暴露风险均在可接受的范围之内。     

Influence of Acidification and Liming on the Distribution of Trace Elements in Surface Waters

Metals in water have been monitored for up to 18 years in acidified regions of Sweden. The concentrations of metals (Al, Cd, Cu, Fe, Mn, Mo, Pb, Zn) were determined by AAS and ICP-MS, the dissolved fractions after separation by in-situ dialysis. Elements showing negative pH-correlation were primarily Al, Zn, Cd, Mn, and Pb, while Mo was positively correlated to pH, indicating a predominance of negatively charged ionic forms. Zn, Cd, and Mn occurred primarily in the dissolved fractions, especially at the lower pH levels. Fe, Al, Pb and Mn were further enriched in humic waters. During the study period, some of the sites were subject to lime treatment, which had a marked influence on most elements, causing the mean levels and the seasonal fluctuations to decrease. Treatment on the lake surface was less effective than wetland liming to reduce seasonal fluctuations, especially for metals mainly originating from the catchments, as Fe and Al.     

江苏省沿海滩涂资源特征及其优化配置

本文分析了江苏省沿海滩涂资源特征及土地资源利用特点，重点讨论并阐述了江苏省沿海滩涂土地资源的优化配置和农业资源综合利用及开发途径　。     

基于N-SPECT模型的胶东半岛土壤侵蚀及泥沙入海通量研究

[目的]探讨土壤侵蚀与土地利用的关系,为胶东半岛海岸带水环境保护和治理以及流域综合管理提供必要的技术支持和参考依据。[方法]在RS-GIS技术支持下,基于N-SPECT模型,对胶东半岛2006—2010年土壤侵蚀量及泥沙入海通量进行模拟。[结果]土壤侵蚀高值区集中于半岛东部和南部,低值区主要分布于半岛中部和中南部。大沽河流域、五龙河流域和大沽夹河流域3大流域对整个胶东半岛的土壤侵蚀贡献最大。针对3大流域之外的其他半岛区域,按照汇水区划分岸段,各岸段单位长度泥沙入海通量的空间差异显著,青岛市城阳区海岸、青岛南端(胶南)海岸、莱州湾东部海岸和威海西南端海岸泥沙通量最大。[结论]土壤侵蚀和产沙与源区土地利用结构密切相关。总体而言,耕地主导型区域是土壤侵蚀严重的区域,而林地和草地具有减轻土壤侵蚀的作用。     

江苏沿海耕地资源量空间分布态势评价

首先采用农用地分等中自然质量分值的计算方法对江苏沿海耕地自然质量进行测算,然后在此基础上结合各乡镇耕地面积和人口数量计算人均耕地量,对江苏沿海地区耕地资源量的空间分布态势进行评价。结果表明:研究区北部、中西部和南部除少数地区外耕地质量总体较好,中东部耕地质量较差;耕地质量优良的地区人均耕地量水平较低,耕地质量较差的地区人均耕地量水平反而较高。根据评价结果,从提高土地整体利用效率、合理占用耕地、合理开发土地后备资源、污染排放源头控制与生产过程中治理相结合等几个方面提出了沿海地区耕地资源可持续利用的有效途径。     

滨海苹果园土壤碳氮空间分布及动态变化研究

土壤有机碳(SOC)和土壤全氮(STN)是土壤肥力和土壤质量的重要组成部分,对维持农田和果园生产力至关重要。以我国典型温带滨海果园—胶东苹果园为对象,采集了不同种植年限果园的488件表层土壤样品,探讨滨海果园SOC、STN含量和密度(SOCD、STND)及碳氮比(C/N)的空间分布、动态变化及其影响因素,为滨海地区及我国苹果园的生产、管理提供基础数据和科学依据。结果表明:胶东苹果园SOC和STN平均含量为10.78和1.42 g kg~(-1),平均密度为2.81和0.37 kg m~(-2),平均C/N为7.70;苹果园SOC、STN、SOCD、STND和C/N块基比分别为0.432、0.340、0.420、0.387和0.391,均表现出中等强度的空间异质性。苹果园SOC、STN和C/N的时空分布受种植年限影响显著。随种植年限延长,SOC呈先增加、再下降的趋势,而STN持续增加,相应地C/N呈先降、后增加再降的趋势。土壤类型、地形条件和土壤酸化对胶东果园碳氮均有不同程度的影响。相对于内陆地区的辽宁西部、北京郊区、陕西渭北和新疆伊犁等地果园,山东胶东滨海苹果园SOC、STN含量和密度较高,C/N偏低,具有较快的周转速度和自身的时空变化特征。     

滨海盐土盐分空间分布的条件模拟和不确定性研究

以海涂围垦区为例,利用普通克立格插值法和序贯高斯条件模拟方法对土壤盐分的空间分布进行估值和模拟,并利用序贯指示条件模拟进行不确定性评价。结果表明,样区东南区域土壤盐分含量较高而北部区域盐分含量低。由普通克立格法得到的土壤盐分的空间分布整体比较连续,具有明显的平滑效应,估值结果数据的分布频率趋于平缓。序贯高斯条件模拟结果整体分布相对离散,突出了原始数据分布的波动性,其模拟结果数据的分布频率相对集中。预测精度上,序贯高斯条件模拟的预测结果精度相对较高。以评价标准204mSm-1作为土壤盐分含量的阈值进行的序贯指示条件模拟结果显示,在土壤盐分含量较高的东南部地区,超过阈值的概率超过75%,而北部很多盐分相对含量低的地区,超过阈值的概率值都低于25%。以超阈值概率为0.9、0.85和0.8三个值来选取盐分的高值风险区进行空间不确定评价,结果表明,联合概率比单点统计的概率更为严格,在划分较大范围高盐风险区域时,最好同时采用联合概率来进行信度评价。