Exceptionally high concentrations of the insect repellent N,N-diethyl-m-toluamide (DEET) in surface waters from Jakarta,Indonesia

Jakarta is a booming coastal megacity in Indonesia with over 10 million inhabitants. The rivers flowing through the city district receive enormous amounts of untreated wastewaters from households and industries and discharge high pollutant loads into Jakarta Bay. Applying a screening approach for the identification of characteristic site-specific and harmful organic contaminants, we frequently found the insect repellent N,N-diethyl-m-toluamide (DEET) in river water and seawater samples from Jakarta. The compound was previously reported as persistent aquatic contaminant in industrial countries, and we present here the first data set from a tropical megacity. Concentrations in river water and seawater from Jakarta were exceptionally high, up to 24,000 ng L^?1, and exceeded by far all published concentrations in surface waters worldwide. We explained this with massive usage of the compound, lack of wastewater treatment and low average river flow as compared to rivers in other tropical megacities. The usage and properties of DEET indicate its suitability as molecular marker of municipal wastewaters. Such markers are useful to trace emissions from specific pollution sources in aquatic systems as a basis for the investigation of related impacts. We show here that DEET is in particular useful to trace the long-range distribution of municipal wastewaters in tropical freshwater and coastal systems. This application is of great value for tracing such inputs in tropical coastal habitats which are sensitive to changing water quality like coral reefs. This assists to uncover whether specific conditions in these systems could be related to pollutant inputs from land.     

水体和沉积物中毒害污染物的生态风险评价方法体系研究进展

人类活动导致大量毒害污染物进入水体和沉积物,从而对水生生物产生诸多不利影响.开展毒害污染物的生态风险评价,筛选高风险毒害污染物,是毒害污染物风险管控和生态系统保护的基础.对美国和欧盟等发达国家和地区毒害污染物的生态风险评价方法进行了综述.水体和沉积物中毒害污染物风险评价的基本方法首先是采用预测或测定环境浓度(PEC或M...     

工业废水毒性鉴定评价方法体系的建议及其应用示例

工业废水是自然环境中毒害污染物的主要来源,对其进行毒性鉴定和评价,是废水毒性管控的基础。我国目前仍缺乏规范的工业废水毒性鉴定和评价体系,本文针对这一状况,综述了美国环保局颁布的废水毒性鉴定评价（TIE）指南和欧盟采用的效应导向分析（EDA）方法,提出了结合TIE方法和EDA方法的优点建立工业废水毒性鉴定评价方法体系的建议,并选取珠三角地区电镀废水作为该体系的应用示例,采用发光菌和重组基因酵母菌进行快速毒性测试,并结合化学分析方法,确定电镀行业废水毒性主要来源于金属Cu和壬基酚聚氧乙烯醚类有机物。     

Duckweeds for water remediation and toxicity testing

The presence of toxic substances in wastewaters and outdoor bodies of water is an important ecotoxicological issue. The aim of this review is to illustrate how duckweeds, which are small, simply constructed, floating aquatic plants, are well suited to addressing this concern. The ability of duckweeds to grow rapidly on nutrient-rich water and to facilitate the removal of many substances from aqueous solution comprises the potential of these macrophytes for the remediation of wastewater and polluted aqueous reservoirs, while producing usable biomass containing the unwanted substances having been taken up. Their ease of cultivation under controlled and even sterile conditions makes duckweeds excellent test organisms for determining the toxicity of water contaminants, and duckweeds are important as model aquatic plants in the assessment of ecotoxicity. Duckweeds are also valuable for establishing biomarkers for the toxic effects of water contaminants on aquatic higher plants, but the current usefulness of duckweed biomarkers for identifying toxicants is limited. The recent sequencing of a duckweed genome holds the promise of combining the determination of water contaminant toxicity with toxicant diagnostics by means of gene expression profiling via DNA microarrays.     

Der Einsatz von Pflanzentests bei der Sedimentbewertung

Up to now, sediment studies have mainly used standardized aquatic bioassays with organisms of the three trophic levels. Among these, algae are the only representatives of the entire plant kingdom. Bioassays with higher plants have hardly been used for the assessment of sediments. The aim of the present study is to demonstrate that the use of higher plants in biotests for analyses of anthropogenically contaminated sediments yields valuable results, which may be included in a concept for the integrated assessment of waters. The contamination by environmental chemicals was determined in the River Elbe by means of samples taken at the Fahlberg-List industrial site at Magdeburg in combination with studies in a reference area on the Müritz-Elde Waterway (Eldenburger Kanal). Sediment extracts and pore waters were tested with the aquatic lemna test. For comparison, first sediment contact tests withLemna minor were tried out. The whole extract of the sediment from Fahlberg-List Magdeburg and one fraction F5 caused distinct damages of the plants. Obviously, the phytotoxic substances of the whole extract are preferentially concentrated in the highly polar fraction F5. A comparison with chemical analytical data proved that the whole fraction F0 and the fraction F5 were heavily contaminated with chemicals. Assays with pore water from this sediment and with the whole sediment also caused a strong inhibition of growth. These results confirm the high contamination of the sediment from Magdeburg. The tests with the reference sediment suggested only a moderate toxic contamination. The results of this study prove that the selected aquatic plant,Lemna minor, is basically able to indicate contamination. In the aquatic test of the sediment extracts, it showed weak, but very selective, responses to certain classes of contaminants. Fractionating of the sample and subsequent chemical analysis combined with toxicity tests allow to narrow down the groups of substances causing toxic effects. This toxicity was confirmed by analyses of the pore waters and whole sediment samples. Together with other toxicity tests (e.g. standardized bioassays) and combined with biological benthos examinations, an overall judgment can be given for the integrated assessment of waters.     

有机粘土矿物对污染环境修复的研究进展

本文综述了国外在有机粘土矿物对污染环境修复研究方面的最新进展，具体介绍了利用表面活性剂制备有机粘土矿物的方法，不同类型有机粘土矿物的特征，有机粘土矿物对各种有机污染物的吸附行为及机理，在地下水污染的现场修复，土地填埋防渗添加材料和去除工业废水有机污染物等方面的应用。     

Environmental effects of aluminium

Aluminium (Al), when present in high concentrations, has for long been recognised as a toxic agent to aquatic freshwater organisms,i.e. downstream industrial point sources of Al-rich process water. Today the environmental effects of aluminium are mainly a result of acidic precipitation; acidification of catchments leads to increased Al- concentrations in soil solution and freshwaters. Large parts of both the aquatic and terrestrial ecosystems are affected.In the aquatic environment, aluminium acts as a toxic agent on gill-breathing animals such as fish and invertebrates, by causing loss of plasma- and haemolymph ions leading to osmoregulatory failure. In fish, the inorganic (labile) monomeric species of aluminium reduce the activities of gill enzymes important in the active uptake of ions. Aluminium seems also to accumulate in freshwater invertebrates. Dietary organically complexed aluminium, maybe in synergistic effects with other contaminants, may easily be absorbed and interfere with important metabolic processes in mammals and birds.The mycorrhiza and fine root systems of terrestrial plants are adversely affected by high levels of inorganic monomeric aluminium. As in the animals, aluminium seems to have its primary effect on enzyme systems important for the uptake of nutrients. Aluminium can accumulate in plants. Aluminium contaminated invertebrates and plants might thus be a link for aluminium to enter into terrestrial food chains.     

Ökotoxikologische Untersuchung von Sedimenten und Schwebstoffen

The potential risk of ground-water contamination through the infiltration of contaminants originating from suspended matter and sediments deposited within flood retention areas in the Upper Rhine valley, as well as subsequent problems for drinking water production, were analyzed by means of the bacterial dehydrogenase activity (DHA; sediment contact test) assay with Arthrobacter globiformis and in a prolonged embryo toxicity assay using zebrafish (Danio rerio). Since the direct uptake of contaminants from particle-bound sources has usually been assumed to play only a minor role in bioaccumulation, the availability of organic extracts to biota has generally been regarded as being overestimated. In order to confirm or discard this hypothesis, organic (acetone) extracts of recently suspended, freeze-dried matter, as well as freeze-dried sediments collected from Rhine flood plains (i.e. soil samples) were compared to corresponding native samples in order to screen for the relative availability of particle-bound contaminants. Whereas a significantly higher ecotoxicological burden was observed for some native soil samples, organic extracts of suspended matter proved to be more toxic than corresponding native samples when compared to organic extracts using each test system. With respect to organic extracts, the suspended matter samples were more toxic than soil samples taken from a rarely flooded site. In contrast to the native samples, the rarely flooded soils revealed a higher toxicity than suspended matter. Therefore, organic extracts did not necessarily overestimate the toxicity of soil and suspended matter samples. Moreover, considerable toxicity of particle-bound contaminants to both bacteria and fish embryos, even in native samples, corroborate the hypothesis that particle-bound contaminants may be more readily available than is generally assumed.     

Investigation of severe water problem in urban areas of a developing country: the case of Dhaka,Bangladesh

The present study evaluated water supply geochemistry in Dhaka City, Bangladesh, to provide detailed trace level (subppb) water quality data that include major ions, low dissolved oxygen (DO) and toxic trace metals for sustainable development. Dhaka Groundwater, which almost uniformly meets the World Health Organization guideline, has become the preferred source. Due to groundwater depletion and an ever-increasing need to meet water demands by city residents, Dhaka water supply and sewerage authority has initiated the treatment of river water, despite the fact that very little is known about the geochemical structure, and trace metal content in the Dhaka water supply. Major ion composition of water samples was determined, and the results used to generate Stiff diagrams. The diagrams served to visually compare water from different sources based on units of mass/volume. Hydrochemical facies analysis showed supply ground and surface waters are comprised predominately of Ca–Na–Mg–HCO₃ and Ca–Na–Mg–HCO₃–Cl types. Spatial distribution of ions, and Na/Cl and Na/SiO₂ molar ratio indicated that silicate weathering is the dominant geochemical process. Chemical data revealed that toxic Cr metal mobilization is associated with chemical hazards from the leather industry. The vulnerability of deep wells to contamination by As is governed by the geometry of induced groundwater flow paths and the geochemical conditions encountered between the shallow and deep regions of the aquifer. Quantifying total arsenic (As) and As from interlocking geochemical cycles (Fe, Mn) may assist in interpreting As dynamics in Dhaka well water. The surface source water was hypoxic to anoxic low DO associated with very high concentrations of biological oxygen demands, and electrical conductivity compared to industrial and non-industrial urban processes and standard activity guidelines. The results of this study should be applied to future research focused on the potential to improve water quality in urban and surrounding areas.     

Isolation of a new toxin from the sponge Latrunculia magnifica in the Gulf of Aquaba (Red Sea)

The sponge Latrunculia magnifica was found to be toxic for fish. A toxin has been isolated from this sponge by organic extraction-column chromatography and thin-layer chromatography. Several chemical properties of the toxin were determined by spectroscopic analysis. Toxicity tests were performed on the fish Gambusia affinis. In vitro experiments showed the toxin to be a cholinesterase inhibitor.     

四种污染物对大型蚤的毒性效应

硫氰酸钠，二甲基甲酰胺，乙腈和丙烯腈是化工生产中排放的有毒有害污染物，会造成水生生物的急性死亡和慢性中毒，破坏水生态系统的生物多样性和功能。为保护水生态系统，需研究这些污染物对水生物的毒性效应，制定其在水中的允许浓度和排旷标准。本文研究了这四种污染物大型蚤的急性和慢性毒性效应，结果表明硫氰酸钠，二甲基甲酰胺，乙腈和丙烯腈对大型蚤的急性毒性值（４８ｈ＝ＥＣ５０）分别为４．２２ｍｇ／Ｌ，３５６１ｍｇ／     

Low-level copper exposures increase visibility and vulnerability of juvenile coho salmon to cutthroat trout predators

Copper contamination in surface waters is common in watersheds with mining activities or agricultural, industrial, commercial, and residential human land uses. This widespread pollutant is neurotoxic to the chemosensory systems of fish and other aquatic species. Among Pacific salmonids (Oncorhynchus spp.), copper-induced olfactory impairment has previously been shown to disrupt behaviors reliant on a functioning sense of smell. For juvenile coho salmon (O. kisutch), this includes predator avoidance behaviors triggered by a chemical alarm cue (conspecific skin extract). However, the survival consequences of this sublethal neurobehavioral toxicity have not been explored. In the present study juvenile coho were exposed to low levels of dissolved copper (5-20 microg/L for 3 h) and then presented with cues signaling the proximity of a predator. Unexposed coho showed a sharp reduction in swimming activity in response to both conspecific skin extract and the upstream presence of a cutthroat trout predator (O. clarki clarki) previously fed juvenile coho. This alarm response was absent in prey fish that were exposed to copper. Moreover, cutthroat trout were more effective predators on copper-exposed coho during predation trials, as measured by attack latency, survival time, and capture success rate. The shift in predator-prey dynamics was similar when predators and prey were co-exposed to copper. Overall, we show that copper-exposed coho are unresponsive to their chemosensory environment, unprepared to evade nearby predators, and significantly less likely to survive an attack sequence. Our findings contribute to a growing understanding of how common environmental contaminants alter the chemical ecology of aquatic communities.     

Thermodynamische Modelle für die Bioverfügbarkeit organischer Chemikalien

In aquatic systems, the bioavailability of chemical contaminants is determined via the physicochemical properties of the compounds and the organic matrices as well as through the milieu parameters of the water. The amount of substance freely dissolved in water yields an approximate characterization of the bioavailable fraction, which can be reduced substantially through the sorption of particulate or dissolved organic matter. For ionogenic compounds, a distinction must be made between the initial substance and dissociated or protonated species which, according to recent results, may also contribute to the bioconcentration found in organisms. The lipophilicity model to estimate bioconcentration factors initially refers only to an estimation of the freely dissolved compound concentration. Analysis of the bioaccumulation of sediment-borne contaminants shows that the uptake mainly occurs via the interstitial water and can be adequately described with the lipophilicity model.     

Brandkatastrophe in Schweizerhalle 1986 — Rückblick und Bilanz

Background

On November 1st 1986, a fire at a Sandoz Ltd. storehouse at Schweizerhalle, an industrial area near Basel, Switzerland, resulted in a chemical contamination of the environment. The storehouse, which was completely destroyed by the fire, contained pesticides, solvents, dyes, and various raw and intermediate materials. The majority of the approximately 1,250 tons of stored chemicals was destroyed in the fire, but large quantities were introduced into the atmosphere, into the Rhine river through runoff of the fire-fighting water and into the soil and groundwater at the site. The chemicals discharged into the Rhine caused massive kills of benthic organisms and fish, particularly eels and salmonides. The public and private reaction to the fire and the subsequent chemical spill was very strong. This catastrophe happened only a few months after the Chernobyl accident and destroyed the myth of the immunity of Switzerland.

Aim

This article reviews the damaging events of November 1986 and aims at striking the balance two decades later.

Results and Discussion

In the aftermath of this once-per-century accident, it was the aim was to gain increased knowledge and understanding in the environmental sciences and to achieve progress for water pollution control issues.The following themes are discussed: Mitigation measures by the chemical industry and by the governmental authorities, activities of environmental protection organisations, chemical and biological monitoring, alert organisation, ecological damages, ecotoxicological effect assessment, recovery and alteration of river biology, return of the salmon, drinking water supplies, research programs, education of environmental scientists and visions for the future.

Conclusions

The catastrophic pollution of the Rhine in November 1986, and the obvious damages of the river biology, triggered significant progress towards the prevention of such environmental catastrophes. The crucial risk reduction measures in the chemical industry, legal regulations and controls as well as chemical and biological monitoring of the river water quality were substantially improved. Politics and chemical industry learned their lectures and proceeded accordingly.

Recommendations

Such a drastic acute contamination, as happened at Schweizerhalle in 1986, is clearly recognizable by the toxic effects. This led to long-term mitigation activities. However, also the less obvious effects of chronic water pollution should receive more attention as well as the on-going alteration of the biocenosis. A high water quality must be demanded in terms of using the Rhine water for drinking water supply. In that context, micropollutants should also be considered, and particular attention should be paid to emerging contaminants.

Perspectives

The big chemical storehouse fire of 1986 induced the transboundary cooperation and improved the willingness for international cooperation. Overall, the effects of the fire catastrophe are positive in terms of a long-term perspective. The whole-basin approach is, on a global basis, an example for other, even more heavily polluted river systems.

     

Anwendung differenzierter Untersuchungsmethoden zur Sedimentbewertung

The aquatic sediments have special significance as habitats of species-rich biocoenoses and as the place where manifold transformation processes occur. Because of their high potential for accumulation of contaminants, sediments are particularly sensitive to anthropogenic impacts, which may disturb the natural state of sediments. In order to protect the aquatic life community, such impacts must be identified, assessed, and the chemical causes of toxic effects must be found. Since the end of the 1980s, the interest for a possibly comprehensive assessment of sediments has increased. This problem can be tackled only by an integrated approach, which combines the detection of toxicity under standardized laboratory conditions with chemical data and biologicalin situ studies into a holistic view. The information value of the results depends essentially on the selection of a diversity of test methods, which are able to indicate contaminant effects differentially. This paper presents results from a comprehensive test approach, which integrates standardized methods (DIN) with pore waters and eluates, as well as tests using the whole sediment. To cover a wider variety of contaminants in the sediment, solvent extracts and fractions thereof were also examined by different bioassays. Chemical analyses examined the structural parameters and identified priority contaminants. Non-target screening could detect a variety of further substances and substance classes. The model organisms of the bioassays responded very differentially and sometimes very intensively to the contaminants in the various investigation media. Especially in sediment extracts, some fractions, and consequently also substances and groups of substances, proved to be particularly toxic. It could be shown that the selected chemical, ecotoxicological, and biological study methods contribute to a holistic assessment. Further, possibly very sensitive bioassays and benthos-biological parameters should be examined aiming to optimize the very wide battery of tests.     

Large-scale spatial variation in epilithic algal matrix cryptofaunal assemblages on the Great Barrier Reef

Spatial variation in the epilithic algal matrix (EAM) cryptofauna was investigated at three locations on the Great Barrier Reef: two inner shelf—Orpheus Island and the Turtle Island group—and a mid-shelf location, Lizard Island. Although the EAM appears to be a relatively simple and consistent habitat, significant differences in cryptofaunal assemblages were found between locations. EAM assemblages from Orpheus Island were markedly different. This appears to be a function of the sediment profile characteristics (grain size >60 µm) at Orpheus Island, as many cryptofaunal taxa displayed positive relationships with sediment volume. However, sediment volumes did not differ significantly between the three locations, highlighting the possibility of cyclonic activity affecting the sediment profile at Orpheus Island in the months preceding the study, in addition to the nutrient input from major terrigenous sources. The results of this study show that EAM cryptofaunal assemblages are not uniform across the Great Barrier Reef and suggest that dissolved nutrients, sediment loads and distance from river systems may be significant drivers of cryptobenthic faunal compositions.     

污染水体中河蚬的生物毒性响应研究进展

河蚬作为广泛分布于世界各国的典型底栖生物,由于其活动性低、滤食性等特征被广泛用作指示生物研究多种水体污染物的生物有效性。但迄今为止,尚没有系统论述污染水体中河蚬生物毒性响应的研究进展。为此,本文从污染物种类、测试指标、试验参数等角度探讨了过去30多年间河蚬在氨、重金属、有机污染物生物富集及生物毒性效应等方面的研究过程及主要成果。以往研究主要以河蚬生物体内累积、形态学及行为学观察、生化指标、代谢组学、基因完整性等指标表征污染水体的生物毒性效应,并随着分子生物学的发展已逐步由多指标全面表征代替单一指标测试。此外,现有研究多偏重于重金属和持久性有机污染物,对氨、新型污染物及纳米材料的河蚬生物毒性效应探讨尚处于起步阶段。河蚬在自然水体污染状况评估、污染水体的生物修复、水体毒性预测等方面具有较高适用性,但河蚬在沉积物毒性鉴定评估(TIE,Toxicity Identification and Evaluation)中的应用研究依然较为缺乏,有待进一步开展。     

Dimethyl disulfide and dimethyl trisulfide: so similar yet so different in evoking biological responses in saprophilous flies

Dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS) are used by saprophilous insects to locate breeding sites (decaying organic matter), and by brood-site deceptive flowers to attract such insects. However, little is known about the relative importance of these two compounds in eliciting electrophysiological and behavioral responses in the insects. Here, we compared the relative attractiveness of DMDS and DMTS to saprophilous flies in field choice experiments and tested whether potential differences in field responses can be explained by differences in electrophysiological antennal responses to these compounds. Field experiments revealed that the attractiveness of a mixture of these compounds is due to DMTS alone. This result was confirmed by electroantennographic recordings in which flies of four tested species of Calliphoridae (Lucilia sericata, L. caesar, Calliphora vicina, Protocalliphora azurea) and one Muscidae (Musca domestica) respond clearly to DMTS, but not to DMDS. In house flies, however, DMTS elicited electrophysiological responses only, not reflected in behavioral assays. Despite the fact that DMTS and DMDS exhibit similar chemical structures, both the electroantennographic and field responses from saprophilous flies to these two compounds strongly differed. Our study suggests that oligosulfide-responsive saprophilous flies rely on DMTS and not DMDS for finding appropriate breeding sites and that DMTS and not DMDS could act as a key mediator for pollinator attraction in brood-site deceptive plants.