Residues of non-phthalate plasticizers in seawater and sediments from Osaka Bay, Japan.

NPPs (Non-phthalate plasticizers) are used as alternative plasticizers to phthalate esters, but there is limited knowledge on environmental residues, and they have not been reported in Japan. A method to analyze NPPs in seawater using solid-phase extraction was developed, and the residual burden of Diisobutyl adipate (DIBA), Acetyl tributyl citrate (ATBC), Di-(2-ethylhexyl) adipate (DEHA), Di-(2-ethylhexyl) sebacate (DEHS) and Trioctyl trimellitate (TOTM) in seawater and sediment from the Osaka Bay was measured. Using an Oasis Max column and acetone as the eluting solvent, the recovery of the target substances in seawater is >68 %. In Osaka Bay, no NPPs were detected in seawater. On the other hand, ATBC and TOTM were detected in the sediment at 36-69 ng/g and 47-131 ng/g, respectively, from about half of the 14 sites, while DEHA and DEHS were detected at 83 ng/g and 181 ng/g, respectively, from only one site.

Current Status of Antifouling Biocides Contamination in the Seto Inland Sea, Japan.

A monitoring survey of antifouling biocides was conducted in the Harima Nada Sea and Osaka Bay of the Seto Inland Sea, Japan to assess contamination by organotin (OT) compounds and alternative biocides. The concentrations of tributyltin (TBT) compounds in surface water ranged from 1.0 to 2.8 ng/L, and the detected TBT concentrations in the bottom water layer were higher than those in the surface water. The concentrations of TBT compounds in sediment samples ranged from 2.0 to 28 ng/g dry weight (dw), respectively. The concentrations of alternative biocides in the water and sediment were lower than those before the banning of TBT by the International Maritime Organization (IMO). Although triphenyltin (TPT) compounds were not detected in water samples, TPT compounds were detected in the range of < 0.1-2700 ng/g dw in sediment samples. Their concentrations in the water samples were as follows: diuron, < 1-53 ng/L; Sea-Nine 211, < 1-1.8 ng/L; Irgarol 1051, < 1-4.0 ng/L; dichlofluanid, < 1-343 ng/L; and chlorothalonil, < 1-1 ng/L, and the ranges of these alternative compounds in sediment samples were diuron, 32-488 ng/g dw; Sea-Nine 211, 47-591 ng/g dw; Irgarol, 33-128 ng/g dw; dichlofluanid, 67-8038 ng/g dw; and chlorothalonil, 31-2975 ng/g dw. Thus, the OTs and alternative biocides have still been detected in water and sediment samples from closed sea areas.

Effects of non-phthalate plasticizer bis(2-ethylhexyl) sebacate (DEHS) on the endocrine system in Japanese medaka (Oryzias latipes).

Water pollution due to plasticizers is one of the most severe environmental problems worldwide. Phthalate plasticizers can act as endocrine disruptors in vertebrates. In this study, we investigated whether the non-phthalate bis(2-ethylhexyl) sebacate (DEHS) plasticizer can act as an endocrine disruptor by evaluating changes in the expression levels of thyroid hormone-related, reproduction-related, and estrogen-responsive genes of Japanese medaka (Oryzias latipes) exposed to the plasticizer. Following the exposure, the gene expression levels of thyroid-stimulating hormone subunit beta (tshß), deiodinase 1 (dio1), and thyroid hormone receptor alpha (trα) did not change. Meanwhile, DEHS suppressed dio2 expression, did not induce swim bladder inflation, and eventually reduced the swimming performance of Japanese medaka. These findings indicate that DEHS can potentially disrupt the thyroid hormone-related gene expression and metabolism of these fish. However, exposure to DEHS did not induce changes in the gene expression levels of kisspeptin 1 (kiss1), gonadotropin-releasing hormone (gnrh), follicle-stimulating hormone beta (fshß), luteinizing hormone beta (lhß), choriogenin H (chgH), and vitellogenin (vtg) in a dose-dependent manner. This is the first report providing evidence that DEHS can disrupt thyroid hormone-related metabolism in fish.

Thyroid hormone disruption by bis-(2-ethylhexyl) phthalate (DEHP) and bis-(2-ethylhexyl) adipate (DEHA) in Japanese medaka Oryzias latipes.

Pollution of water bodies with plasticizers is a serious environmental problem worldwide. In this study, we investigated the effects of plasticizers bis-(2-ethylhexyl) phthalate (DEHP) and bis-(2-ethylhexyl) adipate (DEHA) in Japanese medaka (Oryzias latipes). DEHP significantly increased the expression of all the genes tested: thyroid stimulating hormone beta subunit (tshß-like), tshß, deiodinase 1 (dio1), deiodinase 2 (dio2), and thyroid hormone receptor alpha (trα) and beta (trß). However, DEHA only significantly increased tshß at 7.4 µg/L but significantly decreased dio2 expression at 25.8, 111.1, and 412.6 4 µg/L, while other genes were not significantly affected. Both chemicals reduced eye size and total body length, but did not affect embryo development, hatching time and rate, and swimming performance. DEHA alone affected swim bladder inflation and not DEHP. This is the first report that not only DEHP but also DEHA disrupt thyroid hormone activity in fish. DEHP contamination (13.2 µg/L) was detected in tap water from Kobe, Japan; thus, tap water itself may disrupt thyroid hormone activity in Japanese medaka. Importantly, the effective concentration of DEHP for thyroid hormone-related gene expression and growth was close to or lower than DEHP concentrations reported in surface water elsewhere, indicating that DEHP contamination is a serious aquatic pollution.

Environmental DNA preserved in marine sediment for detecting jellyfish blooms after a tsunami.

Environmental DNA (eDNA) can be a powerful tool for detecting the distribution and abundance of target species. This study aimed to test the longevity of eDNA in marine sediment through a tank experiment and to use this information to reconstruct past faunal occurrence. In the tank experiment, juvenile jack mackerel (Trachurus japonicus) were kept in flow-through tanks with marine sediment for two weeks. Water and sediment samples from the tanks were collected after the removal of fish. In the field trial, sediment cores were collected in Moune Bay, northeast Japan, where unusual blooms of jellyfish (Aurelia sp.) occurred after a tsunami. The samples were analyzed by layers to detect the eDNA of jellyfish. The tank experiment revealed that after fish were removed, eDNA was not present in the water the next day, or subsequently, whereas eDNA was detectable in the sediment for 12 months. In the sediment core samples, jellyfish eDNA was detected at high concentrations above the layer with the highest content of polycyclic aromatic hydrocarbons, reflecting tsunami-induced oil spills. Thus, marine sediment eDNA preserves a record of target species for at least one year and can be used to reconstruct past faunal occurrence.

Comparison of Toxicities of Metal Pyrithiones Including Their Degradation Compounds and Organotin Antifouling Biocides to the Japanese Killifish Oryzias latipes.

Japanese killifish Oryzias latipes were exposed to three levels (0, 1, and 10 µg l-1) of copper pyrithione (CuPT2), zinc pyrithione (ZnPT2), six of their degradation products, and the organotin compounds tributyltin (TBT) and triphenyltin (TPT) for 48 h at 20 °C. All individual fish exposed to 1 and 10 µg l-1 of CuPT2 or 10 µg l-1 of ZnPT2 were dead within 12 h, respectively, and at 24 h the survival rate of the fish exposed to 1 µg l-1 of ZnPT2 was 50%. All fish exposed to 10 µg l-1 of ZnPT2 showed morphological abnormalities in the form of vertebral deformity. None of the fish exposed to six of the degradation products of PTs, TBT, and TPT died during a 48-h exposure period, but various biological effects were observed in the fish exposed to these chemicals: abnormalities of respiration and swimming behavior, and decreased hatchability. Our findings suggest that O. latipes has a higher ecological risk of CuPT2 and ZnPT2 exposure than of TBT and TPT exposure during their life history. Because these antifouling biocides have been used in both freshwater and marine environments, our results highlight these biocides' deleterious effects on the freshwater fish as well as marine fish, and they indicate freshwater and marine pollution.

Study on a new mechanism of sterilization in imposex affected females of tropical marine neogastropod, Thais sp.

The morphological expressions and histopathological analysis of the gonads of a tropical marine neogastropod species (Thais sp.) from East Malaysia revealed new evidence of mechanical sterility in the imposex affected females. The gradual development of imposex was classified into five stages (Stage 0 to Stage 4) with three types of sterility conditions; Type A caused prohibition of copulation and capsule formation; Type B prohibits the releasing process of eggs; and gonads in Type C are infertile. Further analysis is needed to confirm, if the gonad malformation in imposex affected snails is generated specifically by tributyltin (TBT) or by other possible factors. The levels of imposex incidence (stages and percentages) were greater in a marina and decreased with increasing distance from the marina. Organotin tissue burden across the sexes showed that dibutyltin (DBT) as well as TBT might be the elements inducing imposex in Thais sp. from Miri in East Malaysia.

Distribution of antifouling biocides and perfluoroalkyl compounds in sediments from selected locations in Indonesian coastal waters.

Coastal marine environments are considered to be the most sensitive areas for the accumulation of organotin (OT) compounds and other emerging new pollutants, such as perfluoroalkyl compounds. Contamination by these compounds is a matter of great concern due to their accumulation and possible negative impact on the coastal environment and organisms. The concentrations of tributyltin (TBT) compounds were greater in Indonesia, i.e., on the order of Bitung > Manado > Jakarta Bay > Gangga Island, and TBT in sediment from Bitung and Manado was the dominant species among butyltin (BT) compounds. Sea Nine 211, diuron, and irgarol 1051 were detected among alternative biocides in Bitung, Manado, and Gangga Island and irgarol 1051 was detected in Jakarta Bay. Perfluorooctanoic acid (PFOA) and perfluorosulfonic acid (PFOS) in Jakarta Bay were detected at 0.25 to 6.1 µg kg(-1) dry weight (dw) and 0.58 to 3.7 µg kg(-1) dw, respectively, and the concentrations of PFOS at most sampling sites were greater than those of PFOA. Thus, coastal waters from Indonesia have already been contaminated by antifouling biocides and perfluoroalkyl compounds.

Species sensitivity distribution approach to primary risk analysis of the metal pyrithione photodegradation product, 2,2'-dipyridyldisulfide in the Inland Sea and induction of notochord undulation in fish embryos.

To carry out a primary risk assessment in the Inland Sea of Japan for 2,2'-dipyridyldisulfide [(PS)(2)], a metal pyrithione photodegradation product, we used a methodology based on the species sensitivity distribution (SSD) estimated with a Bayesian statistical model. We first conducted growth inhibition tests with three marine phytoplankton species, Tetraselmis tetrathele, Chaetoceros calcitrans, and Dunaliella tertiolecta. We also performed acute and early life stage toxicity (ELS) tests with a teleost fish, the mummichog (Fundulus heteroclitus). The algal growth inhibition tests revealed that the 72-h EC(50) ranged from 62 to 1100 µg/L. Acute toxicity tests with larval mummichogs revealed that the 96-h LC(50) was approximately 500 µg/L based on the actual toxicant concentrations. ELS testing of (PS)(2) under continuous flow-through conditions for 50 days revealed that growth was the most sensitive endpoint, and both total length and body weight were significantly lower in the groups exposed to 27 µg/L (PS)(2) compared to the solvent control group. We determined a lowest observed effect concentration of 17 µg/L and a NOEC of 5.9 µg/L based on the actual toxicant concentrations. By using the ecotoxicity data (LC(50) and EC(50)) from this study and previous work, we calculated a hazardous concentration that should protect 95% and 99% of species (HC(5) and HC(1)) based on the SSD derived with a Bayesian statistical model. The medians with 90% confidence intervals (parentheses) of the HC(5) and HC(1) were 31.0 (3.2, 101.8) µg/L and 10.1 (0.5, 44.2) µg/L, respectively. In the ELS test, about 80% of hatched larvae exposed to 243-µg/L (PS)(2) displayed a notochord undulation. To elucidate the cause of the notochord undulation, we carried out embryo toxicity tests by exposing embryos at various developmental stages to (PS)(2). Exposure to (PS)(2) through the entire gastrulae stage was important to induction of the morphological abnormality. Lysyl oxidase activity was significantly decreased in these embryos compared to the control group, a suggestion that lysyl oxidase-mediated collagen fiber organization, which is essential for notochord formation, is disrupted because of (PS)(2) toxicity. We also investigated the occurrence of (PS)(2) in water from several coastal sites of the Inland Sea and detected (PS)(2) at concentrations of <0.1-0.4 ng/L. Comparison of environmental concentrations to the HC values suggests that the current ecological risk posed by (PS)(2) in the Inland Sea is low. This is the first report of the detection of a metal pyrithione degradation product in the natural marine environment.

Differences in organotin accumulation in relation to life history in the white-spotted charr Salvelinus leucomaenis.

To examine the accumulation pattern of organotins (OTs) in relation to the migration of diadromous fish, tributyltin (TBT) and triphenyltin (TPT) and their derivatives were determined in the muscle tissue of both sea-run (anadromous) and freshwater-resident (nonanadromous) types of the white-spotted charr Salvelinus leucomaenis. Ontogenic changes in otolith strontium (Sr) and calcium (Ca) concentrations were examined along life history transect to discriminate migration type. Mean Sr:Ca ratio from the core to the edge of the otolith in sea-run individuals was significantly higher than those in freshwater-resident one. There were no significant correlations in S. leucomaenis between OT accumulation and various biological characteristics. It is noteworthy that TBT and TPT concentrations in sea-run type were significantly higher than those in freshwater-resident individuals, although they are both of the same species. These results suggest that sea-run S. leucomaenis have a higher ecological risk of OT exposure than freshwater-residents during their life histories.

Distribution of trace metals and methylmercury in soft tissues of the freshwater eel Anguilla marmorata in Vietnam.

This study investigated trace metals in water, sediment, and various organs of the mature eel Anguilla marmorata in the Ba River, Vietnam. The metal concentrations in water and sediment did not exceed the Vietnam water criteria and sediment background concentration, except for Mn and Pb in sediment. The results of metal analysis in eel specimens indicated that the liver and kidney were the dominant organs for almost all trace metals, whereas muscle tended to accumulate high levels of Hg and approximately 87.4-100% of Hg was methylmercury. A strong positive correlation between mercury levels in muscle and age were found, but there was no correlation between mercury and body size. Interestingly, a high concentration of Zn was found in the gonad and liver; this indicated that high levels of Zn in the liver might play a physiologically important role in the eel's biological mechanisms during gonadal maturation. Though almost none of the metal concentrations in the muscle exceeded the reference doses of the U.S. EPA, approximately 80% of eels from the river contained mercury exceeding the recommended levels (0.30 microg/g) of the U.S. EPA and might present a risk for human consumption.

Toxicity of metal pyrithione photodegradation products to marine organisms with indirect evidence for their presence in seawater.

We evaluated the acute toxicities of the metal pyrithiones (MePTs)--copper pyrithione (CuPT) and zinc pyrithione (ZnPT)--to four species of marine algae and a marine crustacean (Tigriopus japonicus). We also performed acute toxicity tests using six of the main MePT photodegradation products: pyridine-N-oxide (PO); 2-mercaptopyridine (HPS); pyridine-2-sulfonic-acid (PSA); 2-mercaptopyridine-N-oxide (HPT); 2,2'-dithio-bis-pyridine ([PS](2)); and 2,2'-dithio-bis-pyridine-N-oxide ([PT](2))-and three marine organisms representing three trophic levels: an alga (Skeletonema costatum), a crustacean (T. japonicus), and a fish (Pagrus major). The acute toxicity values (72-h EC(50)) of CuPT, ZnPT, HPT, (PT)(2), (PS)(2), HPS, PO, and PSA for S. costatum, which was the most sensitive of the test organisms to the chemicals tested, were 1.5, 1.6, 1.1, 3.4, 65, 730, >100,000, and >100,000 microg l(-1), respectively. CuPT was detected in the growth media used for S. costatum tests and in seawater containing HPT or (PT)(2); the concentration of CuPT in seawater containing HPT was highly dependent on the Cu(2+) concentration. These results indicate that in the presence of sufficient Cu(2+), the toxicities of HPT and (PT)(2) should be assessed as CuPT because in Japan MePTs are most frequently used as antifouling booster biocides in conjunction with cuprous oxide.

Assessment of antifouling biocides contaminations in Maizuru Bay, Japan.

The concentrations of organotin compounds in the aquatic environment of Maizuru Bay and their spatial distribution are discussed. The concentrations of tributyltin (TBT) compounds in water samples ranged from 0.001 to 0.002 microg l(-1), and monobutyltin compounds were the dominant species among the butyltin compounds. TBT concentrations in Maizuru Bay are low compared with other coastal waters of Japan. Drastic differences in TBT concentrations were not observed among the Maizuru Bay sites. Phenyltin compounds were not detected in the water samples. Concentrations of TBT and triphenyltin (TPT) in sediment from Maizuru Bay ranged, respectively, from 0.9 to 11 microg kg(-1), from 0.2 to 17 microg kg(-1) dry weight (dw). TBT concentrations in Maizuru Bay were lower than those in other coastal areas of Japan. TPT concentrations were greater than TBT concentrations in the fishing port. The concentrations of TBT and TPT in blue mussels (M. galloprovincialis) from Maizuru Bay were in the range of 2.4 to 9.3 microg kg(-1) and 0.2-13 microg kg(-1) wet weight (ww), respectively. A tolerable average residue level (TARL) was estimated at 74.8 microg kg(-1) from a tolerable daily intake (TDI) of 0.25 bis(tributyltin)oxide microg kg(-1) body weight day(-1). TBT concentrations detected in blue mussel samples were lower than the TARL values. The acceptable concentration of TPT, which were calculated using acceptable daily intake instead of TDI, was 127 microg kg(-1). Concentrations of TPT in blue mussel samples were also lower than the TARL. TBT compounds in blue mussel samples were at similar levels among the various sampling sites, indicating that TBT is not currently being used in ship hull paints; the ratios of degradation products of TBT and TPT were greater than those of the parent compounds. Concentrations of alternative biocides in water samples were also investigated in the bay. Although Sea-Nine 211, M1, and Pyrithiones were not detected, Diuron and Irgarol 1051 were detected at 0.010-0.257 and at 0.002-0.018 microg l(-1), respectively. Concentrations of Diuron were great in the shipping route and near the shipyard, whereas the concentration of Irgarol 1051 was great at the fishing port. Concentrations of Diuron and Irgarol 1051 in sediment from Maizuru Bay ranged, respectively, from <0.08 to 12, from <0.08 to 9.8 microg kg(-1) dw, respectively. Despite being a semi-enclosed bay, we found that sediment in Maizuru Bay is not contaminated by alternative biocides to the degree found in other coastal areas. Copper concentrations of sediment were at ordinary levels, and those of blue mussels were slightly lower than those reported previously in other coastal areas of Japan. In both the sediment and blue mussels, there was no correlation between the presence of copper and antifouling biocides.

Occurrence of antifouling biocides and fluorinated alkyl compounds in sediment core from deep sea: Suruga Bay, Tosa Bay, and Nankai tough, Japan.

Contamination profiles of antifouling biocides were investigated in a deep-sea environment in Suruga Bay Japan. Significant differences in the tributyltin (TBT) and triphenyltin (TPT) concentrations in subsurface sediment between 850 and 800 m of water depth were not observed (p < 0.05). Organotin (OT) concentrations in sediment core of 0-30.5 cm from a water depth of 800 m were investigated. The butyltins (BTs) and phenyltins (PTs) concentrations were constant between 0 and 15 cm, and, subsequently, the concentration of these compounds increased. The peaks of the BTs and PTs concentrations were observed between 18 and 19 cm. The concentrations of Irgarol 1051 decreased until a core depth of 9 cm, and, the values then became near the detection limit under the 10 cm of core depth. Perfluorooctane sulfonate (PFOS) and perfluorooctanic acid (PFOA) were detected in the sediment core (0-30.5 cm) of Suruga Bay. The concentration of PFOS was high in the 0-5-cm core depth and then decreased. The concentrations of PFOA, however, were at the values near the detection limit throughout the sediment core. The BTs and PTs concentrations in surface sediment from Tosa Bay decreased with water depth. Although Irgarol 1051 was the only alternative compound detected, the value was near the detection limit. PFOS and PFOA were detected in sediment core from Tosa Bay. The concentrations of PFOS became low as the water depth became deeper. TBT, TPT, Sea Nine 211, Diuron and Irgarol 1051 were detected in sediment core (core depth: 10 cm) from the Nankai trough (water depth: 4010 m).

Inhibition of acetylcholinesterase by metabolites of copper pyrithione (CuPT) and its possible involvement in vertebral deformity of a CuPT-exposed marine teleostean fish.

In a previous study, we demonstrated that exposure to an antifouling biocide, copper pyrithione (CuPT), early during life induced vertebral deformity in the larvae of a marine fish, the mummichog (Fundulus heteroclitus). Skeletal deformities may be caused by inhibition by of acetylcholiensterase (AChE) activity, and to elucidate the mechanism underlying the CuPT-associated vertebral deformity, we first examined whether CuPT, zinc pyrithione (ZnPT), and their degradation products could inhibit AChE activity in the fish. Two of the degradation products, 2,2'-dipyridyldisulfide [(PS)(2)] and 2,2'-dithiobispyridine-N-oxide [(PT)(2)], but neither CuPT nor ZnPT, exhibited prominent AChE-inhibiting activity. Secondly, thin-layer chromatography revealed that mummichog hepatic microsomes metabolized CuPT to produce (PS)(2) in a microsome-dependent manner. The AChE inhibition induced in CuPT-exposed fish is likely due to (PS)(2) that was produced through metabolism of acquired CuPT. (PS)(2) may cause therefore skeletal deformity in CuPT-exposed fish by means of its neuromuscular blocking properties, through a mechanism similar to that proposed for animals exposed to organophosphorous pesticides.

Contamination profiles of antifouling biocides in selected coastal regions of Malaysia.

The concentrations of butyltins (BTs) in sediment from Peninsular Malaysia along the Strait of Malacca and their spatial distribution are discussed. The concentrations of BTs were high in the southern part of Peninsular Malaysia where there is a lot of ship traffic, because trade is prosperous. The concentrations of monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT) in sediment from the coastal waters of Peninsular Malaysia were in the range 4.1-242 microg/kg dry weight (dw), 1.1-186 microg/kg dw, and 0.7-228 microg/kg dw, respectively. A higher percentage of TBT was observed in the area where TBT concentrations were high. The concentrations of monophenyltin (MPT), diphenyltin (DPT), and triphenyltin (TPT) were in the range <0.1-121 microg/kg dw, 0.4-27 microg/kg dw, and 0.1-34 microg/kg dw in sediment from Peninsular Malaysia, respectively. MPT was the dominant phenyltin species. MBT, DBT, and TBT in green mussel (Perna viridis) samples were detected in the range 41-102 microg/kg, 3-5 microg/kg, and 8-32 microg/kg, respectively. A tolerable average residue level (TARL) was estimated at 20.4 microg/kg from a tolerable daily intake (TDI) of 0.25 microg TBTO/kg body weight/day. The maximum value of TBT detected in green mussel samples was the value near the TARL. TPTs were not detected in green mussel samples. The concentrations of Diuron and Irgarol 1051 in sediment from Peninsular Malaysia were in the range <0.1-5 microg/kg dw and <0.1-14 microg/kg dw, respectively. High concentrations of these compounds were observed in locations where the concentrations of TBT were high. Sea Nine 211, Dichlofluanid, and Pyrithiones were not detected in sediment. The concentrations of antifouling biocides in Melaka and the Strait of Johor were investigated in detail. BTs were found in similar concentrations among all sampling sites from Melaka, indicating that BT contamination spread off the coast. However, Sea Nine 211, Diuron, and Irgarol 1051 in the sediment from Melaka were high at the mouth of the river. BT concentrations at the Strait of Johor were higher than those in Peninsular Malaysia and Melaka and were high at the narrowest locations with poor flushing of water. The concentrations of antifouling biocides were compared among Malaysia, Thailand, and Vietnam. A higher concentration and wide variations of TBT and TPT in sediment from Malaysia were observed among these countries. The Irgarol 1051 concentrations in sediment from Malaysia were higher than those in Thailand and Vietnam.

Monitoring the organotin contamination in the Taihu Lake of China by bivalve mussel Anodonta woodiana.

As a part of the pilot study on "Freshwater Mussel Watch", butyltin (monobutyltin, MBT; dibutyltin, DB; tributyltin, TBT), and phenyltins (monophenyltin, MPT; diphenyltin DPT; triphenyltin TPT) were analyzed in soft tissues of 15 bivalve mussels Anodonta woodiana sampled from five separate sites (Huzhou, Xueyan, Dapu, Sansandao, and Wulihu) around the Taihu Lake of China in 2004. The residue of total butyltins and total phenyltins in the all mussels ranged 142-1693 and 3.0-90 ng Sn g(-1) dry weight, respectively. Except for the mussels from Xueyan, DBT and MBT accounted more than 60% of total butyltins in those from other four sites. In contrast, TPT were usually almost 100% of the mussels studied. The present study provides most recent information about the organotin contamination in the Taihu Lake, and suggests Anodonta woodiana can be used as a suitable bioindicator.

Early life-stage toxicity test for copper pyrithione and induction of skeletal anomaly in a teleost, the mummichog (Fundulus heteroclitus).

We used a teleost fish, the mummichog (Fundulus heteroclitus), to conduct early life-stage toxicity testing for copper pyrithione (CuPT). Fertilized mummichog eggs were exposed to CuPT at various concentrations for 50 d under continuous flow-through conditions. Hatchability, survival, growth, and morphologic abnormalities were measured. Hatchability did not differ significantly between any experimental group and control groups. Survival and growth were significantly reduced at 50 d in the groups exposed to 2 or 4 microg/L CuPT. During the test, morphologic abnormalities, such as vertebral deformity and formation of inflammatory masses in the lateral muscles, occurred in fish exposed to CuPT. Light and electron microscopic studies indicated that muscle dysfunction played a role in the vertebral deformity and revealed that the inflammatory mass was composed mainly of macrophages and necrotic myocytes. We consider that macrophages infiltrated and phagocytized necrotic cells, thus forming the inflammatory mass. In addition, acetylcholinesterase activity was markedly decreased in the 2- and 4-microg/L exposure groups, suggesting the skeletal deformity was due to mechanisms similar to those proposed for organophosphorous pesticide exposure.

Concentrations of organotin compounds in the stranded killer whales from Rausu, Hokkaido, Japan.

We measured the concentrations of butyltin (BT) and phenyltin (PT) compounds in blubber, liver, lung, and muscle of seven stranded killer whales (Orcinus orca) collected from Rausu, Hokkaido, Japan. BTs in blubber (n = 6), liver (n = 4), lung (n = 1), and muscle (n = 4) of adult whale were in the range of 37-90, 385-676, 15, and 26-53 microg kg(-1) wet weight, respectively. Concentrations of PTs in blubber, liver, lung, and muscle were <1 to 58, <1 to 14, 7 and <1 to 4 microg kg(-1) wet weight, respectively. Detected frequencies of PTs were low in all tissues. Higher percentages of monobutyltin (MBT) in blubber, lung, and muscle were observed, while the percentage of dibutyltin (DBT) was high in liver. Detected frequencies of triphenyltin (TPT) were highest among tissues. Total BT concentrations in blubber and liver of a whale calf were lower than those in adult whales. MBT and DBT in the liver of the calf were the same (42%). MBT in blubber was the dominant compound among BTs.

Accumulation of organotin compounds in tissues and organs of dolphins from the coasts of Thailand.

The concentration of organotin (OT) in seven species of dolphin (bottlenose dolphin, finless porpoise, Indo-Pacific humpbacked dolphin, long-beaked common dolphin, Pantropical spotted dolphin, spinner dolphin, and striped dolphin), which were stranded on the coasts of Thailand, were measured. Butyltin (BT) and phenyltin (PT) compounds in tissues and organs of the dolphins were in the range of 16-1,152 microg kg(-1) and <1-62 microg kg(-1), respectively. The highest concentration of tributyltin (TBT) was generally observed in the liver. Because of the lower concentration of TPT, a trend in body distribution was not observed. Monobutyltin (MBT) among all the BTs was the dominant species in tissues and most organs except the liver. However, dibutyltin (DBT) was predominant in the liver. Monophenyltin (MPT) was not detected in all dolphins in the study. The higher concentration of BTs was observed with the increase in body length of dolphins. On the other hand, no significant difference in the concentration of OTs between genders was observed. The concentrations of OTs in tissues and organs were compared among dolphin, whales, and dugongs stranded on the coasts of Thailand. The concentrations of BTs were high and in the order of whales > dugongs > dolphins and the concentrations of PTs in whales were higher than those in dolphins and dugongs.