Contaminant trends in US National Estuarine Research Reserves

Inputs of toxic chemicals provide one of the major types of anthropogenic stress threatening our Nation's coastal and estuarine waters. To assess this threat, the National Oceanic and Atmospheric Administration's (NOAA’s) National Status and Trends (NS&T) Program Mussel Watch Project monitors the concentrations of more than 70 toxic chemicals in sediments and on the whole soft-parts of mussels and oysters at over 300 sites around the U.S. Twenty of the 25 designated areas that comprise NOAA's National Estuarine Research Reserve System (NERRS) have one or more Mussel Watch monitoring sites. Trace elements and organic contaminants were quantified including As, Ag, Cd, Cu, Hg, Ni, Pb, Zn, ΣPCBs, ΣPAHs, DDT and its metabolites, and butyltins. The Mussel Watch sites located in or near the 20 Reserves provide for both status and trends. Generally the Reserves have trace element and organic contaminant concentrations that are at or below the median concentration determined for all NS&T Mussel Watch monitoring data. Trends were derived using the Spearman-rank correlation coefficient. It was possible to determine if trends exist for sites at which six or more years of data are available. Generally no trends were found for trace elements but when trends were found they were usually decreasing. The same general conclusion holds for organic contaminants but more decreasing trends were found than for trace elements. The greatest number of decreasing trends were found for tributyltin and its metabolites. (PDF contains 203 pages)

Magnitude and extent of sediment toxicity in selected estuaries of South Carolina and Georgia

Toxic chemicals can enter the marine environment through numerous routes: stormwater runoff, industrial point source discharges, municipal wastewater discharges, atmospheric deposition, accidental spills, illegal dumping, pesticide applications and agricultural practices. Once they enter a receiving system, toxicants often become bound to suspended particles and increase in density sufficiently to sink to the bottom. Sediments are one of the major repositories of contaminants in aquatic envronments. Furthermore, if they become sufficiently contaminated sediments can act as sources of toxicants to important biota. Sediment quality data are direct indicators of the health of coastal aquatic habitats. Sediment quality investigations conducted by the National Oceanic and Atmospheric Administration (NOAA) and others have indicated that toxic chemicals are found in the sediments and biota of some estuaries in South Carolina and Georgia (NOAA, 1992). This report documents the toxicity of sediments collected within five selected estuaries: Savannah River, Winyah Bay, Charleston Harbor, St. Simons Sound, and Leadenwah Creek (Figure 1). (PDF contains 292 pages)

An assessment of two decades of contaminant monitoring in the Nation’s Coastal Zone.

Executive Summary: Information found in this report covers the years 1986 through 2005. Mussel Watch began monitoring a suite of trace metals and organic contaminants such as DDT, PCBs and PAHs. Through time additional chemicals were added, and today approximately 140 analytes are monitored. The Mussel Watch Program is the longest running estuarine and coastal pollutant monitoring effort conducted in the United States that is national in scope each year. Hundreds of scientific journal articles and technical reports based on Mussel Watch data have been written; however, this report is the first that presents local, regional and national findings across all years in a Quick Reference format, suitable for use by policy makers, scientists, resource managers and the general public. Pollution often starts at the local scale where high concentrations point to a specific source of contamination, yet some contaminants such as PCBs are atmospherically transported across regional and national scales, resulting in contamination far from their origin. Findings presented here showed few national trends for trace metals and decreasing trends for most organic contaminants; however, a wide variety of trends, both increasing and decreasing, emerge at regional and local levels. For most organic contaminants, trends have resulted from state and federal regulation. The highest concentrations for both metal and organic contaminants are found near urban and industrial areas. In addition to monitoring throughout the nation’s coastal shores and Great Lakes, Mussel Watch samples are stored in a specimen bank so that trends can be determined retrospectively for new and emerging contaminants of concern. For example, there is heightened awareness of a group of flame retardants that are finding their way into the marine environment. These compounds, known as polybrominated diphenyl ethers (PBDEs), are now being studied using historic samples from the specimen bank and current samples to determine their spatial distribution. We will continue to use this kind of investigation to assess new contaminant threats. We hope you find this document to be valuable, and that you continue to look towards the Mussel Watch Program for information on the condition of your coastal waters. (PDF contains 118 pages)

Investigation of unusual mortalities of bottlenose dolphins along the mid-Texas coastal bay ecosystem during 1992

An investigation was conducted into the deaths of more than 220 bottlenose dolphins (Tursiops truncatus) that occurred within the coastal bay ecosystem of mid-Texas between January and May 1992. The high mortality rate was unusual in that it was limited to a relatively small geographical area, occurred primarily within an inshore bay system separated from the Gulf of Mexico by barrier islands, and coincided with deaths of other taxa including birds and fish. Factors examined to determine the potential causes of the dolphin mortalities included microbial pathogens, natural biotoxins, industrial pollutants, other environmental contaminants, and direct human interactions. Emphasis was placed on nonpoint source pesticide runoff from agricultural areas, which had resulted from record rainfall that occurred during the period of increased mortality. Analytical results from sediment, water, and biota indicated that biotoxins, trace metals, and industrial chemical contamination were not likely causative factors in this mortality event. Elevated concentrations of pesticides (atrazine and aldicarb) were detected in surface water samples from bays within the region, and bay salinities were reduced to <10 ppt from December 1991 through April 1992 due to record rainfall and freshwater runoff exceeding any levels since 1939. Prolonged exposure to low salinity could have played a significant role in the unusual mortalities because low salinity exposure may cause disruption of the permeability barrier in dolphin skin. The lack of established toxicity data for marine mammals, particularly dermal absorption and bioaccumulation, precludes accurate toxicological interpretation of results beyond a simple comparison to terrestrial mammalian models. Results clearly indicated that significant periods of agricultural runoff and accompanying low salinities co-occurred with the unusual mortality event in Texas, but no definitive cause of the mortalities was determined. (PDF file contains 25 pages.)

Der PAH-Metabolit 1-Hydroxypyren in der Galle von Klieschen (Limanda limanda) aus Nord- und Ostsee

Due to their carcinogenic properties, polycyclic aromatic hydrocarbons (PAH) are important environmental contaminants which may lead to increased levels of neoplastic aberrations in fish liver. To measure the PAH contamination of fish, concentrations of PAH metabolites were determined in the bile. The main metabolite 1-hydroxypyrene was determined in concentrations from < 0.8 to 189 ng/ml in bile of dab caught in the North Sea and the Baltic Sea re-spectively. The concentrations are comparable to levels of 1-hydroxypyrene measured in cod and herring from the Baltic Sea. The highest concentrations in dab bile were measured in fish from the inner German Bight and the Kiel Bight.

Der Fischei-Test: Ein Toxizitätstest für ökotoxikologische Untersuchungen

Zebrafish (Danio rerio) embryos have been used to quantify the teratogenic potential of environmental samples and harmful substances respectively. The short spawning interval renders this species a good test organism in toxicological research. Due to the transparency of the eggs several lethal and non-lethal endpoints can be detected in parallel after 48 h of embryonic development. Zebrafishembryos have been shown to be sensitive to a number of environmental relevant contaminants, as well as to ex-tracts from polluted sediments

Untersuchungen zu biologischen Schadstoffeffekten bei Nordseefischen: Langzeitdaten zum Auftreten von Lebertumoren bei der Kliesche (Limanda limanda)

Data are presented on the spatial distribution and long-term temporal trends in the occurrence of neoplastic liver lesions of North Sea dab (Limanda limanda) in the period 1988 to 2001, obtained in the framework of the regular fish disease monitoring programme carried out by the German Federal Research Centre for Fishery. Highest prevalences consistently recorded in the first part of the period occurred in the German Bight, at the Dogger Bank and at sampling sites off Humber and Wash. In contrast, stations in the northern North Sea (e.g. in the Firth of Forth area) were always characterised by low prevalences. Particularly during the first years of observation, a clear and general decrease in prevalence could be observed, that was most pronounced in the hot spot areas German Bight and Dogger Bank compared to the Firth of Forth. Current data reveal that, due to the decrease, spatial differences between sampling sites are now much less obvious than at the beginning of the studies. Limited chemical data available suggest that the temporal decrease in prevalence of liver tumours and their precursor stages generally correspond with the decrease in organic contaminants in dab livers as well as in water and sediments. However, the spatial variation in prevalence recorded can not entirely be explained by contaminant levels. For instance, the prevalence was continuously low in the Firth of Forth area wheras the contaminant levels in dab were comparatively high. The opposite feature was observed at the Dogger Bank. Future studies will therefore address the role of other host- and site-specific factors potentially involved in the aetiology of the disease.

BECPELAG: Ein internationaler Workshop über biologische Schadstoffeffekte in pelagischen Ökosystemen

Im Februar 2001 begann unter der Schirmherrschaft des Internationalen Rates für Meeresforschung (ICES) und der Ozeanographie Kommission der UNESCO (IOC) der internationale Workshop Biological Effects of Contaminants in Pelagic Ecosystems, BECPELAG mit folgenden Zielen: • Untersuchungen über das Auftreten biologischer Effekte von Umweltschadstoffen auf Meeresorganismen in der Freiwasserzone (Pelagial) der Nordsee • Überprüfung von Methoden zur Erkennung von biologischen Schadstoffeffekten in pelagischen Organismen auf ihre Eignung für zukünftige Überwachungsprogramme

Ostseehering (Clupea harengus) - eine Rohwarenressource für die deutsche Fischwirtschaft?

Baltic Sea herring is a traditional raw material for the German fish processing industry and the fresh fish market. This applies also for the spring herring of the spawning population of the waters around the island of Rügen. Reduction of the fat content to about 5 % during the spawning cycle limits the processing possibilities of mature herring from this area. Failures in taste and odour (tainting), a common problem of the past have not been detected in the last 3 years. Infestation by nematodes are comparable to other herring stocks and contamination levels of organic and inorganic contaminants are well below allowable limits. The annual German fishing quota of about 85000 t of Baltic Sea herring is now utilised only to 10 %. For a stronger utilization of this stock as in the 70th and 80th , there are scarcely prerequisites. The project of a central processing plant on the island Rügen for about 50000 t of herring as raw material is not realistic. The answer to the question asked at the beginning of this article, whether Baltic Sea herring represents a raw material for the German fish processing industry, is YES, dispite some restrictions.

Lipophile organische Rückstände im Nahrungsmittel Fisch. Eine aktuelle Bestandsaufnahme

Lipophilic organic substances in the environment are nearly exclusive of anthropogenic origin. Input of contaminants to sea and fresh water lakes arise via rivers, the atmosphere, direct intake and disposals. Intake by fish occurs via diet or directly from the water. The contamination level in fish is influenced by the fishing ground, fat content, biological cycle and age of the fish. But the effect for fish as food is very limited. Levels of lipophilic organic contaminants in the edible part of fish important for human consumption are far below the German maximum allowable evels of residues and pollutants.

Sustainable management of water bodies for small-scale fisheries resorces research and development

Abstract The rapid growth of both formal and informal high density urban settlements around major water resources has led to increased pollution of streams, rivers, lakes and estuaries, due to contaminated runoff from these developments. The paper identified major contaminants to be : organic waste (sewage), industrial effluent, pesticides and litter. Pollutant loads vary depending on the hydrology of the urban area, local topography and soil conditions. In some instances, severe pollution of neighbouring and downstream water courses has been observed. The management of catchment land uses, riparian zones, in stream habitat, as well as in stream water flow patterns and quality are necessary in order to sustain the integrity and "health" of water resources, for fisheries and other developments. As such, attempts to ensure a certain level of water quality without attention to other aspects will not automatically ensure a "healthy" ecosystem even as fish habitat. Proper management leads to better water quality and conducive environment for increased fish production

Entgiftungsstoffwechsel der Nordsee-Kliesche (Limanda limanda)

In the framework of monitoring programmes organized under several sea protection conventions (HELSINKI Conv., OSPAR Conv.) the contracting parties are requested to develop appropriate techniques for Biological-Effect- Monitoring. In following these recommendations the Institut for Fisheries Ecology studies the 7-ethoxyresorufin- O-deethylase (EROD) activity in the liver of dab. EROD represents one enzyme of the cytochrome P-450 species, also called mixed function oxygenases (MFO), which is induced by certain organic contaminants, e.g. PCBs. On the other hand, an influence of natural factors like season, temperature or spawning on the EROD activity may be possible. The present study represents an insight into the status of the EROD activity in North Sea dab. Ultimately, we intend to decide if EROD activity is an appropriate tool to detect effects of contaminants. The EROD activity in the liver of 687 dabs, caught in the North Sea at different seasons in 1995 and 1996 with the fishery research vessel “Walther Herwig III”, has been determined and the data obtained have been statistically evaluated. The logarithmically transformed values of the EROD activity are following approximately a normal distribution. Due to the wide variation of the enzyme activities and due to the small number of samples minor differences between samples are not detectable. Nevertheless, comparing the enzyme activities at different sites of the North Sea, some significant differences have been identified. A model for the discription of seasonal variations of EROD activity, developed at the Biologische Anstalt Helgoland, could be helpful for interpretation.

Wetlands and coastal water quality: Should wetland size matter?

Generally, wetlands are thought to perform water purification functions, removing contaminants as water flows through sediment and vegetation. This paradigm was challenged when Grant et al. (2001) reported that Talbert Salt Marsh (Figure 1.) increased fecal indicator bacteria (FIB) output to coastal waters, contributing to poor coastal water quality. Like most southern California wetlands, Talbert Salt Marsh has been severely degraded. It is a small (10 ha), restored wetland, only 1/100th its original size, and located at the base of a highly urbanized watershed. Is it reasonable to expect that this or any severely altered wetland will perform the same water purification benefits as a natural wetland? To determine how a more pristine southern California coastal wetland attenuated bacterial contaminants, we investigated FIB concentrations entering and exiting Carpinteria Salt Marsh (Figure 2.), a 93 ha, moderate-sized, relatively natural wetland.(PDF contains 4 pages)

Some potential occupational and environmental hazards associated with fish pond production in Nigeria

The paper highlights the concept of information and the significance of environmental and occupational hazards associated with pond fish production in Nigeria and discuss the possible options for the ways forward. The major raw material used in fish production system is the organic manure (cow dung, poultry droppings, porcine manure etc) that serves as substrate for heterotrophic production of bacteria and protozoa, which act as food for zooplankton and the fish. The pathogenic organisms (viruses, bacteria, protozoa's, and parasites), are noted for the potential hazard to the fish handlers and consumers. Nine species from seven genera of bacteria associated with fish diseases are found to have association with diseases of human such as typhoid fever, bacillary dysentery and other gastrointestinal tract related problems. Also the environmental contaminants in pond fish production become important because of its significance to consumers' acceptance of the fish products

Management of Biesboch reservoirs for quality control with special reference to eutrophication

The three Biesbosch Reservoirs are pumped storage reservoirs, fed with rather polluted and highly eutrophic water from the River Meuse. Air injection at the bottom of the reservoirs prevents thermal stratification, which would otherwise result in serious water quality deterioration. Reservoir mixing also serves as an economic algal control measure; mixing over sufficient depth causes light to play the role of limiting factor and this, combined with zooplankton grazing, keeps the biomass of phytoplankton at acceptable levels. Special problems are caused by benthic, geosmin-producing Oscillatoria species growing on the inner embankment. Rooting up the bottom with a harrow is used as the method of control, based on underwater observations by biological staff trained as SCUBA-divers. With regard to pollutant behaviour the three reservoirs act as a series of fully mixed reactors. This enables the application of kinetic models to describe their behaviour and allows the use of a selective intake policy, e.g. for suspended solids with associated contaminants, ammonia and polynuclear aromatic hydrocarbons. A combination of selective intake and self- purification processes - enhanced by the compartmentalisation of the storage volume in three reservoirs - leads to a striking improvement for many water-quality parameters.