Butyltin compounds and their relation with organic matter in marine sediments from San Vicente Bay—Chile

Tributyltin and its degradation products, mono-and dibutyltin have been determined in sediments collected in some representative sites in San Vicente Bay, Chile. The organic matter contents of sediments and water collected simultaneously from the same sampling sites were also determined. High levels of total organic carbon were found in sediments, especially in those from the northern part of the bay (1.80-8.87%). Good correlations were found between total organic carbon and the oxidizable and refractory carbon fractions. Among the butyltin species determined, TBT presented the highest levels, ranging from 14 to 1,560 ng Sn g(-1) dry weight. Concentration ratios of TBT to DBT ranged between 1.33 and 3.10, showing a high degree of contamination in sediments of this Chilean bay. All data obtained were analysed by the chemometric method of principal components analysis. A strong correlation was found between TBT and DBT concentrations in sediments, the different organic matter contents in sediments and water. In marine organisms only TBT was detected, containing the filterer organism Semele solida higher level than Perumytilus purpuratus and Pyura chilensis (220, 150 and 120 ng Sn g(-1) dry weight, respectively). For the alga Rodoficea iridae the TBT concentration was 60 ng Sn g(-1) dw. Comparatively, these values are higher than those reported for the same kind of marine organisms worldwide. The different samples from San Vicente Bay were found to be contaminated by TBT. This contamination can be attributed to the different anthropogenic activities taking place in the bay.     

Spatial and temporal distribution of tributyltin (TBT) in seawater, sediments and bivalves from coastal areas of Korea during 2001–2005

Tributyltin (TBT) concentrations were determined in seawater, sediments and bivalve samples collected from Korean coastal areas during 2001-2005, to investigate the levels and temporal variation in TBT contamination in relation to the timing of the imposition of regulations on TBT use in Korea. TBT concentrations ranged from <5.0 to 164 ng/L in seawater, from <7.0 to 9,576 ng/g dry weight in sediments, and from <7.0 to 6,296 ng/g dry weight in bivalves. The highest concentrations of TBT were found at locations close to intensive shipping traffic and industrial complexes, and the contamination at some hot spot areas was high enough to cause harmful effects on marine organisms. TBT concentrations and their occurrence in Korean coastal waters have been decreasing annually. In particular, TBT concentrations in seawater have dramatically decreased. This result is consistent with regulations and bans on the use of TBT in Korea.     

Stability and storage problems in organotin speciation in environmental samples

The stability of both tributyltin (TBT) and triphenyltin (TPT) in water, sediment, oysters and cockles was studied over a period of 18 months using several storage conditions. Butyltins were stable in unacidified sea-water stored in polycarbonate bottles in the dark at 4 degrees C for 7 months, but half of the TBT concentration was lost after 540 d. A comparable preservation time was achieved for butyltins stored on C18 cartridges at room temperature. However, phenyltins extracted from sea-water were stable for only 60 d stored on cartridges and even more pronounced losses (about 90% after 540 d) occurred when they were stored in either polycarbonate or Pyrex glass bottles. Losses of organotins were observed in sediments after air drying and pasteurization treatments using a freeze-dried sediment as a comparator, whereas both butyltin and phenyltin species remained stable in sediments stored at -20 degrees C for the 18 months tested, irrespective of the treatment used for stabilization. Air drying followed by pasteurization was shown to be superior to other treatments for the stabilization of organotin compounds in sediments stored at higher temperatures, but 30% of TBT was lost after 540 d at 25 degrees C. Finally, butyltins were stable in both frozen cockles and oysters in the dark over a 7 month period and in freeze-dried samples stored at 4 degrees C for 5 months, but TBT losses of about 70% were observed after 540 d.     

Butyltin Compounds in Sediments of the Bahía Blanca Estuary, Argentina

Systematic measurements of both Tributyltin (TBT) and Dibutyltin (DBT) in sediments along different locations in the inner zone of Bahía Blanca estuary were done. Two samples were taken near the main dry dock facility, at Puerto Belgrano naval base, in Argentina. TBT concentrations from non-detected to 170.3 ng Sn g⁻¹ were measured in the inner region of the estuary, and higher one of 3,288 ng Sn g⁻¹ near the dry dock at Puerto Belgrano. DBT values ranging between non-detected and 75.2 ng Sn g⁻¹ were obtained along the principal channel, but extreme concentration of 1,645 ng Sn g⁻¹ was measured at Puerto Belgrano. These values show that this estuary is affected by organotin pollution, mainly in areas of heavy shipyard activities.     

Metals, Boron, and Selenium in Neosho Madtom Habitats in the Neosho River in Kansas, U.S.A.

In 1991 and 1992 we determined the levels of metals, arsenic, boron, and selenium in the Neosho River drainage in southeastern Kansas, the primary habitat for the threatened Neosho madtom (Noturus placidus). We evaluated concentrations in sediments, mussels (Quadrula pustulosa and Q. metanevra), and fish(Percina phoxocephala, Cyprinus carpio,and Ictiobus bubalus) from three sites on theNeosho River and one site on the Cottonwood River. We also evaluated contaminant concentrations in C. carpio composite samples collected by theKansas Department of Health and Environment (KDHE)at two additional locations on the Neosho River in1990–92. Sediments were contaminated by lead. Concentrations of selenium, boron, and most metalsin mussels were low to normal for biota. Arseniclevels in mussels and fish suggest low-levelcontamination of biota. Aluminum, barium, manganeseand strontium concentrations were much higher inmussels than in fish. Five fish composite sampleshad cadmium concentrations that indicate chronicdeleterious effects on biota. Lead concentrationsin six fish samples were elevated. Mercuryconcentrations in most large fish compositesexceeded concentration for protection of animalsthat might consume them. We believe that reductionsin cadmium, lead, and mercury contamination, inparticular, would benefit aquatic life in theriver.     

Trace Element Concentrations in Fish, Surficial Sediments and Water from Northern Part of the Persian Gulf

Concentrations of cadmium, lead, nickel and vanadium were determined in water, surficial sediments and the muscle of three demersal fish species (Epinephelus coioides, Psettodes erumei and Solea elongate) from 15 sampling sites in the northern part of Persian Gulf. Concentrations of the elements were determined using Inductively Coupled Plasma Mass Spectrometer. There were no significant differences among the sampling sites in Cd and Pb levels in the sediments. The highest concentrations of Ni and V in sediments were found near the southern coast of Qeshm Iland and Bandar Lengeh. Concentrations of Cd, Pb and Ni in the sediments were notably higher than global baseline values. Nearly in all cases the element concentrations in the sediments were considerably greater than RSA (ROPME Sea Area) and the ERL (Effects Range Low) guidelines. Significant differences among the sampling sites could be found for concentrations of all the four metals in water. The mean Ni, Pb and Cd levels in the water samples were relatively higher than those in some other regions of the Persian Gulf. Except few cases, the mean concentrations of the elements in muscle of the selected fish species were markedly below the international guidelines for human consumption.     

Butyltin levels in several Portuguese coastal areas

This work aimed to report present levels (2007–2008 sampling) of tri- (TBT), di- (DBT), and monobutyltin (MBT) in surface sediments from 11 Portuguese coastal sites and discuss the evolution of BTs contamination in the last two decades. All the samples revealed quantifiable values of TBT, DBT, and MBT with total butyltin concentrations between 1 and 565 ng/g (of Sn in dry sediment). Maximum level of TBT, 66 ng/g, was observed in Sado estuary, at Lisnave site, in the proximity of a big shipyard. MBT decreased site by site by the same order as DBT and TBT did, but its concentrations were much higher in many cases, denoting that TBT contamination was much higher in the past. A comparison with the available previous data confirmed a marked decrease of TBT contamination all over the last years, indicating that the main sources of TBT in Portuguese coastwise stopped effectively.     

Liver lesions in demersal fishes near a large ocean outfall on the San Pedro Shelf, California

The prevalence of toxicopathic liver lesions in demersal fish on the San Pedro Shelf, California was determined for a 15-year period (1988–2003). Fish livers were sampled at fixed locations as part of the Orange County Sanitation Districts (OCSD) ocean monitoring program. Histopathological examination of selected fish liver tissues was studied to determine whether the wastewater discharge had affected fish health. The prevalence of toxicopathic lesion classes neoplasms (NEO), preneoplastic foci of cellular alteration (FCA), and hydropic vacuolation (HYDVAC) varied among species and locations. For all species sampled, severe lesions occurred in 6.2% of the fish examined (n = 7,694). HYDVAC (4.1%) was the most common toxicopathic lesion type followed by FCA (1.4%) and NEO (0.7%). HYDVAC occurred only in white croaker (Genyonemus lineatus), accounting for 84.8% of the toxicopathic lesions for this species. Prevalence of HYDVAC, NEO, and FCA in white croaker was 15.2, 2.0, and 0.7%, respectively. The prevalence of HYDVAC and NEO in white croaker increased with age and size but there was no sexual difference. A linear regression model was used for hypothesis testing to account for significant differences in fish size (and age for croakers) at the different sampling locations. This analysis showed that for HYDVAC there was no spatial or location effect for lesion rate or size/age of onset. For NEO, the model predicted that white croaker near the wastewater outfall may acquire these lesions at a smaller size/younger age, and at a higher rate, than at other sites. However, this result may be biased due to the unequal size frequency distributions and the low prevalence of NEO in white croaker at the different sampling sites. Bigmouth sole (Hippoglossina stomata) had a prevalence of FCA and NEO of 1.3 and 0.35%, respectively, but the prevalence and distribution of lesions was too few for statistical testing. There was no sexual difference for lesion prevalence in hornyhead turbot (Pleuronichthys verticalis) and the prevalence of FCA and NEO was 3.4 and 0.37%, respectively. FCA prevalence increased with size in hornyhead turbot and there were no significant spatial differences for lesion rates and fish size at lesion onset. Overall, consistent spatial differences for lesion prevalence were not demonstrated and highlight the analytical difficulties of detecting a possible point source impact when the effect is rare, correlated with the size/age structure of the population, and may be caused by exposure to unknown multiple sources. Thus, the usefulness of liver histopathology as a point-source monitoring tool is best applied to where the spatial scale of impact generally exceeds the home range of the target species.     

Cadmium and Lead Levels in Fish (Tilapia Nilotica) Tissues as Biological Indicator for Lake Water Pollution

Cadmium and lead were determined in different tissues (muscle,gill, stomach, intestine, liver, vertebral column and scales) of Tilapia nilotica from the High Dam Lake, Aswan (Egypt) to assess the lake water pollution with those toxic metals. Fish samples were chosen from different ages and weights to be analyzed along with samples of the aquatic plant(Najas armeta), sediment and lake water.The results showed that cadmium and lead concentrations were higher in fish scales and vertebral column than in the other parts of the fish. Cadmium and lead levels in High Dam lake water and fish (Tilapia nilotica) were a result of the pollution which uptakes from aquatic plants, sediments andgasoline containing lead that leaks from fishery boats. Tilapia nilotica fish was used as a good bio-assay indicator for the lake pollution with cadmium and lead. The fish musclesin this study were in the safety baseline levels for man consumption.     

Factors affecting food chain transfer of mercury in the vicinity of the Nyanza Site,Sudbury River,Massachusetts

The influence of the Nyanza Chemical Waste Dump Superfund Site on the Sudbury River, Massachusetts, was assessed by analysis of sediment, fish prey organisms, and predator fish from four locations in the river system. Whitehall Reservoir is an impoundment upstream of the site, and Reservoir #2 is an impoundment downstream of the site. Cedar Street is a flowing reach upstream of the site, and Sherman Bridge is a flowing reach downstream of the site. Collections of material for analysis were made three times, in May, July, and October. Sediment was analyzed for acid-volatile sulfide (AVS), simultaneously-extracted (SEM) metals (As, Cd, Cr, Hg, Pb, Sb, Zn), and total recoverable Hg. The dominant predatory fish species collected at all sites, largemouth bass (Micropterussalmoides), was analyzed for the same suite of metals as sediment. Analysis of stomach contents of bass identified smallfish (yellow perch Perca flavescens, bluegill Lepomismacrochirus, and pumpkinseed Lepomis gibbosus), crayfish,and dragonfly larvae as the dominant prey organisms. Samples of the prey were collected from the same locations and at the sametimes as predator fish, and were analyzed for total and methyl mercury. Results of AVS and SEM analyses indicated that sediments were not toxic to aquatic invertebrates at any site. The SEM concentrations of As, Cd, and Cr were significantly higher at Reservoir #2 than at the reference sites, and SEM As and Cdwere significantly higher at Sherman Bridge than at Cedar St. Sediment total Hg was elevated only at Reservoir #2. Hg washigher at site-influenced locations in all fish speciesexcept brown bullhead (Ameiurus nebulosus). Cd washigher in bluegill, black crappie (Pomoxis nigromaculatus),and brown bullhead, and Cr was higher in largemouth bass filletsamples but not in whole-body samples. There were no seasonal differences in sediment or prey organism metals, but some metalsin some fish species did vary over time in an inconsistent manner. Predator fish Hg concentration was significantly linearlyrelated to weighted prey organism methyl Hg concentration. Largemouth bass Hg was significantly lower at Reservoir #2 in our study than in previous investigations in 1989 and 1990. High concentrations of inorganic Hg remain in river sediment asa result of operation of the Nyanza site, and fish Hg concentrations in river reaches downstream of the site areelevated compared to upstream reference sites. However, thedifferences are relatively small and Hg concentrations inlargemouth bass from the site-influenced locations are nohigher than those from some other, nearby uncontaminatedsites. We hypothesize that this results from burial ofcontaminated sediment with cleaner material, which reducesbioavailability of contaminants and possibly reducesmethylation of mercury.     

Butyltin contamination in sediments and seawater from Kaohsiung Harbor, Taiwan

The distribution of butyltin (BT) compounds in the sediments and seawater, at the river outfalls, fishing ports, shipyards, and industrial zone docks of Kaohsiung Harbor, Taiwan were investigated. Twenty sediment and seawater samples were collected from various locations in the Harbor in 2006 and analyzed for monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT). Results showed that the concentration of total BTs varied from 1.5 to 151 ng/g in sediment samples, with TBT being the major component of the sediment samples. This suggests that sediments could be the most possible sink of TBT brought by the sorption mechanism. The concentrations of BTs ranged from 9.7 to 270 ng/L in seawater samples, whereas DBT and MBT, the degradation byproducts of TBT, were mainly the most abundant BT compounds of the seawater samples. This indicates that the abiotic or biotic degradation potential of TBT was significant. Spatially, the highest concentrations of BTs were observed in both water and sediment samples collected from the shipyard and fishing port areas. This indicates that the shipping-related activities (e.g., navigation, ship repair, and ship building) would contribute most of BTs in the environment. Results show that the concentrations of degradation products (DBT and MBT) were related closely to temperature, salinity, dissolved oxygen (DO), and chlorophyll-a of the seawater. This implies that seasonal changes of the water parameters controlled the degradation of TBT in seawater. The observed levels of BT compounds in both seawater and sediments were much higher than those required to induce toxic effects on marine organisms, suggesting that appropriate TBT control strategies should be taken in Kaohsiung Harbor.     

Fractionation of butyltin species during sample extraction and preparation for analysis

Solvent extraction and evaporative concentration steps are often used in procedures for the measurement of butyltins in environmental samples. As part of a larger study utilizing radiolabeled butyltins, the loss and fractionation of butyltins during sample preparation was investigated. TBT, DBT, and MBT were extracted from acidified seawater by hexane with efficiencies of about 95–99, 50–60 and 11% respectively. In addition, losses of about 70% of DBT were found during evaporative concentration of hexane. A variety of sediment extraction procedures were tested and none were found to be highly efficient for total butyltin extraction.     

Depositional profiles and relationships between organotin compounds in freshwater and estuarine sediment cores

A range of organotin compounds including tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) were measured in sediment cores collected from contaminated freshwater and estuarine sites in Essex and Suffolk, U.K. Butyltin compounds were found in significant quantities at depths of up to 60 cm within the sediments of marina and boatyard complexes with TBT concentrations ranging from <3 ng g^–1 (the detection limit) to >3000 ng g^–1. In general sediment TBT concentrations decreased with depth, but maximum enrichment tended to occur just below the surface. It was evident from these core profiles that the accumulation of organotins in surface deposits was on the decline and coincided approximately, with the implementation in 1987 of the UK retail ban on the sale of TBT based antifouling paints for application on vessels <25 m in length. The degradation rate for TBT in sediments was found to exhibit first order kinetics with half lives ranging from 0.9–5.2 years between different sites. Estimated degradation rates have also been determined for DBT and MBT. These ranged from 1.5–3.0 years for DBT and 1.8–3.7 years for MBT.     

Butyltin and copper monitoring in a Northern Chesapeake Bay marina and river system in 1989: An assessment of tributyltin legislation

This study was designed to: (1) evaluate dibutyltin (DBT) and tributyltin (TBT) bi-weekly in the water column for four months during the peak boating season (June–September, 1989) at seven stations in the Back Creek and Severn River area of Maryland waters of Chesapeake Bay; (2) compare butyltin values from the 1989 study with values obtained from a similar butyltin monitoring study conducted in 1988 (after Maryland TBT legislation) and 1986 (before Maryland TBT legislation); (3) determine the extent of TBT paint use in the Back Creek area by surveying boat owners; (4) determine dissolved copper concentrations from three of the seven stations bi-weekly during the four-month study; and (5) compare dissolved copper concentrations at these stations with previous copper data collected in 1988.Mean four-month DBT concentrations ranged from 10 to 73 ng/L at the seven stations. Highest DBT concentrations occurred at Station 1 in a marina; lowest concentrations occurred at Station 7 in the Severn River. Mean four-month TBT concentrations ranged from 177 ng/L at Station 1 (marina) to 21 ng/L at Station 7 (Severn River). Maximum TBT concentrations of 361 and 570 ng/L occurred at marina SDtations 1 and 3, respectively. Temporal trends in both DBT and TBT (station mean concentrations by date) showed that peak concentrations occurred during the early part of the boating season followed by reductions in late summer and early fall. Spike concentrations of both DBT (117 and 62 ng/L) and TBT (308 and 366 ng/L) were reported on two sampling dates near a boat maintenance facility in Back Creek.There was a significant reduction in DBT concentrations from 1986 to 1989 when date was treated as a fixed effect. However, TBT concentrations were not significantly reduced between 1986 and 1989 when mean concentrations of TBT were averaged across stations and dates for each year. A significant reduction was reported at Station 1 (marina station) when each station was examined for differences between years. TBT was also reported to significantly decrease (p=0.0442) at Station 7 between 1988 and 1989. A boat owner survey in the study area showed that 6% of the recreational boats that were surveyed were painted with TBT paint in 1989. This was a significant decrease in TBT paint use from the previous year when 31% of recreational boat owners surveyed used TBT paints.An evaluation of dissolved copper concentrations at three stations in the study area in 1989 showed that mean concentrations from bi-weekly sampling for four months was 10 g/L at Station 1, 7.8 g/L at Station 4 and 2.7 g/L at Station 7. Copper concentrations decreased with distance away from the Back Creek marinas. Copper concentrations at all three stations were significantly lower in 1989 than in 1988.     

Assessment of the exposure of two fish species to metals pollution in the Ogun river catchments, Ketu, Lagos, Nigeria

The concentrations of metals (Ca, Cd, Fe, Mn, Pb and Zn) were determined by flame atomic absorption spectrophotometry in water, sediments and fish samples in the Ogun river catchments, Ketu, Lagos, which is an important bird nesting, fishing and drinking water source. The results show that the southern tip bothering the Lagos lagoon is where the highest metal concentrations are found in the fish species (Tilapia sp. and Chrysichthys sp.), whereas the Agboyi creek segment near the lagoon with higher surrounding human population density recorded higher levels of metals in sediments and water samples. The two fish species accumulated different amounts of metals. However, the differences were not statistically different at p < 0.05. There is a significant correlation (p < 0.05) for Cd concentration in water. The concentrations of Pb in sampling points 3 and 4 as well as Cd, Mn and Fe in all six sampling points exceeds the World Health Organization (WHO) limits for drinking water. Levels of metals obtained for sediments are within the range reported for Nigeria’s river sediments. Based on this study, the human risks for heavy metals in the harvested fish species from the Ogun river catchments, Ketu, are low for now as the concentrations were below the recommended Food and Agriculture Organization (FAO) maximum limits for Pb (0.5 mg/Kg), Cd (0.5 mg/Kg), and Zn (30 mg/Kg) in fish.     

Spatial and temporal distribution of butyltin compounds in a Northern Chesapeake Bay Marina and river system

This study was designed to: determine dibutyltin (DBT), tributyltin (TBT) and tetrabutyltin (TTBT) bi-weekly for a four month period (June-September 1986) in the Port Annapolis Marina, Mears Marina, Back Creek and Severn River area of Northern Chesapeake Bay; measure DBT, TBT and TTBT for five successive days (Thursday-Monday) to determine possible daily effects (weekday versus weekend) and determine DBT, TBT and TTBT every two hours for one full tidal cycle in the study area. Maximum concentrations of TBT were reported at both Port Annapolis Marina (1801 ng L^–1) and Mears Marina (1171 ng L^–1) during early June followed by significant reductions in TBT during late summer and early fall. All 4 Back Creek Stations also had highest concentrations of TBT in early June; significant reductions occurred during the next three months. The highest concentration of TBT reported in the Severn River (48 ng L^–1) occurred in September. The lowest TBT value (5 ng L^-1) at this station occurred in June. TTBT was not detected in any of the samples. The day of week sampled (Thursday-Monday) during the daily experiments was not found to significantly affect TBT concentrations. TBT evaluations every two hours during the tidal cycle demonstrated that values peaked at 1400 and 1600 hr time intervals. Peak concentrations of TBT occurred during a rising tide. The possible consequence of the measured TBT concentrations for aquatic biota are discussed.     

Organotins in marine mammals and seabirds from Norwegian territory

An increasing number of studies indicate that marine mammals and some seabirds are exposed to organotins. However, results from northern and Arctic areas are few. Here results from analysis of tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT), triphenyltin (TPhT), diphenyltin (DPhT) and monophenyltin (MPhT) in harbour porpoise (Phocoena phocoena), common seal (Phoca vitulina), ringed seal (Phoca hispida) and glaucous gull (Larus hyperboreus) from Norwegian territory are presented. Relatively high concentrations of DBT, TBT and MBT were observed in muscle, kidney and liver from harbour porpoises caught in northern Norway in 1988, just before restrictions on the use of tributyltin (TBT)(mainly on small boats) were introduced in several European countries. The concentrations in harbour porpoise muscle tissue were reduced significantly 11 years later, possibly as a result of the introduced restrictions. Considerably lower concentrations of butyltins were observed in the seals compared to porpoises. The lowest levels of organotins were found in ringed seals from Spitsbergen, where only traces of dibutyltin (DBT) and monobutyltin (MBT) were observed. Traces of DBT and MBT were also found in some individual glaucous gulls from Bear Island. The sum of the degradation products MBT and DBT in liver samples from all analysed species were generally higher than TBT itself. Triphenyltin (TPhT) was observed in all porpoise samples and in livers of common seals. Also the sum of the degradation products MPhT and DPhT in liver samples from porpoise and common seals were higher than TPhT. No traces of phenyltins were found in ringed seals from Spitsbergen or in glaucous gulls from Bear Island. The limited data available indicate low to moderate exposure to organotins in northern areas (Spitsbergen and Bear Island). Marine mammals are however more exposed further south along the Norwegian Coast.     

Distribution characteristics of polycyclic aromatic hydrocarbons in sediments and biota from the Zha Long Wetland, China

In this paper, the concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured in biota (reed, grass, mussel, fish, and red-crowned crane) and sediments collected from seven locations in the Zha Long Wetland. PAHs were recovered from the sediments and biota by ultrasonic extraction and then analyzed by means of gas chromatography-mass spectrometry. The total PAH concentrations were 244–713 ng/g dw in sediments, 82.8–415 ng/g dw in plants and 207–4,780 ng/g dw in animals. The total sediment PAH concentrations were categorized as lower to moderate contamination compared with other regions of China and the world. In the plant samples, the accumulation abilities of reed roots and stems for PAHs were higher than those of grass roots. In addition, the concentration of individual PAHs in mussel muscles was the highest in all of the animal samples, followed by fish, feeding crane fetuses, and wild crane fetuses. Compositional analysis suggests that the PAHs in the sediments from the Zha Long Wetland were derived from incomplete biomass combustion. Risk assessment shows that the levels of PAHs in sediments are mostly lower than the effects range mean value (effects range mean), whereas only naphthalene in all sample sites was higher than the effects range low value. It is worthwhile to note that benzo(b)fluoranthene, benzo(k)fluoranthene, indeno(1,2,3-cd)pyrene and benzo(ghi)perylene were detected in crane fetal, which have potential carcinogenicity for organisms from the Zha Long Wetland.     

Results from the NOAA National Status and Trends Program on distribution and effects of chemical contamination in the coastal and estuarine United States

The NOAA National Status and Trends (NS&T) Program has been monitoring chemical contamination in fish livers, and surface sediments since 1984 and in molluscan tissue and sediments since 1986. Data from fine-grained sediment at 175 sites are used to describe the spatial distribution of contamination throughout the coastal and estuarine United States. Highest levels are generally found in, and considered representative of, urban areas. It should be noted, however, that these levels are not as high as have been found near discharge pipes or in isolated industrial areas through other monitoring efforts. Dramatic biological responses, such as liver tumors in fish or apparently toxic contaminant levels in sediment, are found infrequently. Subtle biological changes, especially those that affect reproductive ability, are being sought. Data from three annual collections of mollusks have been used to identify early signals of temporal trends in contamination at NS&T sites.