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PubMed1996

First report of pectenotoxin-2 (PTX-2) in algae (Dinophysis fortii) related to seafood poisoning in Europe.

Pectenotoxin-2 (PTX-2), a polyether-lactone included in the neutral class of diarrhoetic shellfish poisoning (DSP) toxins, has been unambiguously detected in Dinophysis fortii collected in the northern Adriatic Sea (Emilia Romagna coasts). This is the first report of such a toxin in Europe. This lipid soluble toxin was identified both in crude methanolic phytoplankton extract and in the neutral fraction obtained by extract chromatography on a basic alumina column. The techniques used were reversed phase high-performance liquid chromatography followed either by UV diode-array detection (LC-UV-DAD) or by mass spectrometry (LC-MS) and tandem mass spectrometry (LC-MS-MS) using an atmospheric-pressure ionization source and an ionspray interface. Okadaic acid (OA) was also found in the D. fortii specimens and quantified as 15 pg/cell. Although quantitation of PTX-2 was not possible due to the lack of pure toxin, the high PTX-2:OA ratio suggested PTX-2 was significant in the D. fortii specimens. The presence of PTX-2 in a region with no previous report of DSP neutral toxic compounds may indicate a risk of human poisoning. Serious efforts should therefore be made to develop suitable routine methods capable of detecting the presence of PTXs in biological materials of marine origin, in order to assure the wholesomeness of seafood products.

Chromatography, Liquid↗

PubMed1994

Screening for planar chlorobiphenyl congeners in tissues of marine biota by high-performance liquid chromatography with photodiode array detection.

A rapid method has been developed to screen for planar chlorobiphenyl (CB) congeners, as well as certain other CBs and DDTs, in tissue samples from marine biota. The analytes were extracted from tissue matrices with 1:1 hexane/pentane (v/v) and interfering compounds were separated from the CBs on a gravity-flow column packed with acidic, basic and neutral silica gel eluted with 1:1 hexane/methylene chloride (v/v). Subsequently, the planar CB congeners were resolved from the DDTs and other CBs by HPLC on Cosmosil PYE analytical columns cooled to 9 degrees C and were measured by an ultraviolet (UV) photodiode array (PDA) detector. Two important advantages of PDA over conventional UV detection were the ability to identify individual analytes by comparing their UV spectra to those of reference standards and the ability to establish the spectral homogeneity (purity) of the analytes by comparing spectra within a peak to the apex spectrum. The HPLC/PDA method was tested with tissue samples from fish, shellfish and marine mammals; concentrations of certain CBs and DDTs in samples determined by screening compared favorably with those in the same samples analyzed by a comprehensive method (e.g., gas chromatography/high resolution mass spectrometry). However, the HPLC/PDA method was about an order of magnitude less sensitive than determinations by comprehensive methods.

Adipose Tissue↗

PubMed1983

Polychlorinated terphenyls (PCTs) use, levels and biological effects.

Polychlorinated terphenyls (PCTs) have almost identical characteristics to high chlorinated PCBs: extremely stable, bioaccumulable and biomagnification through food webs might take place. PCT is especially used in investment casting waxes and as a substitute for PCB. In spite of the limited use until now, PCT has been detected in a great variety of environmental samples such as soil, water, shellfish, fish, seals, birds and terrestrial animals. Furthermore, it has been found in paper products and foodstuffs. PCT residues in human tissues--blood, liver, fat and milk--have been detected in some countries. Animal experiments have shown that long-term toxic effects of PCT are of most importance. PCT has a marked inductive effect on the microsomal enzymes in the liver in vertebrates and may cause liver-damage--including tumours. Disturbance of the hormonal--and immunological--systems have also been reported. The most important ecological hazard of PCT--as well as PCB--is the possible disturbance of the reproduction system of the organisms. Many countries do not regulate the use of PCT. In some countries the use of PCT is regulated to closed systems, but the expansion of usage is under consideration in the EEC.

Adipose Tissue↗

PubMed1986

Seasonal variation of copper and zinc concentrations in the oyster Saccostrea cuccullata from the Dampier Archipelago, Western Australia: implications for pollution monitoring.

The intertidal rock oyster Saccostrea cuccullata, sampled at eight sites on eight occasions over a 1-year period, contained mean Cu and Zn concentrations ranging between 34 and 267 and 206 and 4078 mg kg-1 dry weight, respectively. In the study area, Cu and Zn emanate from sewage and boat slips (antifouling paints), while Zn probably also originates from coolant water from an electricity power generating station and iron ore exporting facilities. Highest oyster wet weight, Cu and Zn concentrations and loads occurred in January (spawning period), indicating that metal variation was not reciprocating wet weight. Lowest metal concentrations and loads occurred in October (period of onset of gametogenesis), while lowest wet weight occurred in April (post-spawning period). No significant (P less than 0.001) variation in the wet to dry weight ratio was noted temporally. However, significant, though slight, variation was noted between polluted and unpolluted oysters. Results of this study indicate that pollution control monitoring programs should consider: seasonal variation of metal concentrations; portion of the year during which standards are exceeded; oyster size and availability for human consumption; suitability of standards where shellfish are not consumed as a staple diet; appropriate size indicies which can be used for selecting specimens for intersite comparisons; wet to dry weight calculations: techniques, spatial and temporal variations; and the physical dynamics of sites used.

Animals↗

PubMed1996

Uptake of mercury species by transplanted mussels Mytilus galloprovincialis under estuarine conditions (Krka river estuary).

Biometric features and physico-chemical conditions are responsible for many of the variables for metal concentrations in indigenous populations of mussels. In order to reduce variations and promote the utility of mussels as bioindicator organisms for environmental mercury concentration levels, individuals of approximately uniform biometric characteristics, selected from a culture of 1-year-old mussels (Mytilus galloprovincialis, Lmk., were transplanted to four locations in the Krka river estuary and nearby coastal area (Eastern Adriatic coast). Biometric parameters of mussels and their total and methylmercury content were analysed four times over a period of 270 days in 1988/89. It was found that total and methylmercury concentrations were significantly correlated with shell weight, wet weight and dry weight of mussels. The estimate of minimal methylmercury concentration in the water of the Krka River Estuary (approximately 20 pg/l), derived from the mussels data, is in a good agreement with recently determined concentration levels of methylmercury (between 50 and 100 pg/l) in waters of the same area. The accumulation efficiency for methylmercury is about 20-50 times higher than for total mercury. Only 1% of the total mercury content, and 20-50% of the methylmercury content in water filtered by the mussels, is accumulated in the shellfish tissues.

Animals↗

PubMed1985

Evaluation of immediate adverse reactions to foods in adult patients. I. Correlation of demographic, laboratory, and prick skin test data with response to controlled oral food challenge.

Forty-five adult patients, referred to here as the index population, with a history of immediate adverse reactions after food ingestion were evaluated by history, physical examination, laboratory studies, and skin testing. Fifty-six percent of these patients reported adverse reactions to only one food, whereas 84% of the patients reported up to three foods as being capable of eliciting reactions. The average age obtained by history at which adverse reactions began to occur was 19 4/5 yr. The occurrence of these reactions persisted over an average of 14 4/5 yr. Most reactions involved the gastrointestinal tract alone or in combination with the skin or respiratory tract. The most frequently involved foods were shellfish, peanuts, eggs, fish, tomatoes, and walnuts. Twenty-five of the patients participated in oral challenge with the suspected food. The food challenge was positive in 10 patients. Comparison of information obtained by history including personal or family history of any other allergic disease, age of onset of sensitivity, the length of time of suspected sensitivity in years, and the number of foods to which the sensitivity was believed to exist revealed no significant differences between food challenge-positive (FC+) and food challenge-negative (FC-) patients. However, a significant difference in the reaction patterns reported by history in the FC+ and FC- patients was noted in that FC+ patients more often described reactions in which a combination of gastrointestinal, respiratory, and dermatologic symptoms occurred. The complete blood count with differential, blood chemistries, and serum immunoglobulin levels were similar in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

PubMed1991

Food-dependent, exercise-induced anaphylaxis: a study on 11 Japanese cases.

Eleven patients with food-dependent, exercise-induced anaphylaxis were studied. Seven patients experienced anaphylactic symptoms only after eating certain foods, such as shellfish, wheat, and grape before exercise. In the remaining four patients, no specific food could be identified, but the act of eating itself predisposed to anaphylaxis. Their anaphylactic symptoms were all clearly distinguished from cholinergic urticaria by history. Patients who developed anaphylactic symptoms before 20 years of age (N = 7) were atopic themselves or had atopic first-degree relatives. Six patients had increased serum IgE levels, and IgE antibodies against the causative food allergens were detected by the skin prick test or RAST in four cases. In contrast, patients who developed the symptoms after 30 years of age (N = 4) appeared to have a less atopic background, and IgE levels were within normal range except in one case. Three of four patients in the latter group developed symptoms after ingesting food made of wheat followed by exercise. All patients were sensitive to wheat as determined by the skin prick test. In six of 11 patients, a considerable rise in plasma histamine concentration was observed after exercise challenge with treadmill alone, and food intake followed by exercise induced a further increase in one patient.

Adolescent↗

PubMed1977

Chlorinated benzenes in the environment.

Chlorinated benzenes are composed of twelve chemical species: one mono-, three di-, three tri-, three tetra-, one penta-, and one hexachlorobenzene. Most of these are not only important intermediates for various kinds of chemicals but are also extensively employed for various applications singly or in combination. For example, 1,4-dichlorobenzene is used chiefly against termites in soil; trichlorobenzenes are used as solvents for pesticides and also as heat transfer agents with PCBs; the mixture of trichlorobenzene and tetrachlorobenzene is applied in controlling shellfish predators; and hexachlorobenzene is applied to wheat as a fungicide in some countries and as an additive to rubber products. The annual production (1973) of monochlorobenzene, 1,2-dichlorobenzene, and 1,4-dichlorobenzene in Japan was about 23,000, 9000, and 20,000, tons, respectively. Production volumes of other chlorinated benzenes are not well known but are assumed to be smaller than those of the above three compounds. The total annual production of chlorinated benzenes far surpasses the peak production of PCBs (7000 tons/year) which are known as a ubiquitous pollutant in this country. Since chlorinated benzenes have a chemical structure and properties similar to those of PCBs and PCTs, it seemed necessary to direct our attention to environmental contamination by these materials. The present paper describes only the occurrence and the fate of these materials. Toxicity and biological impact are not referred to here.

Air Pollution↗

PubMed1992

Mercury concentration correlates with the nitrogen stable isotope ratio in the animal food of Papuans.

The relationships among element concentrations (Na, Mg, Al, P, K, Ca, Cr, Fe, Mn, Cu, Zn, Sr, total Hg, organic Hg, inorganic Hg, Pb) and stable carbon and nitrogen isotope ratios (13C/12C and 15N/14N) in animals consumed by the people called Gidra, who inhabit the lowland of Papua New Guinea, were examined. Animals analyzed included mammal, bird, fish, shellfish, reptile, crustacean, and insect. Highly significantly positive correlations were observed between total Hg concentrations and 15N/14N (r = 0.796), between organic Hg concentrations and 15N/14N (r = 0.781), and between inorganic Hg concentrations and 15N/14N (r = 0.739). This was interpreted to indicate that Hg was an element which accumulates in animals along the food chain. Based on the regression function of Hg on delta 15N, the bioconcentration factor for total, organic, and inorganic Hg was estimated to be 5.

Diet↗

PubMed1994

Detection of potential virulence markers of Vibrio vulnificus strains isolated from fish in Sweden.

A variety of potential virulence markers such as the production of cytotoxin, haemolysin, exoenzymes, bactericidal action of sera, presence of capsule and adhesion to human intestinal cells were investigated on Vibrio vulnificus strains isolated from eels in Sweden. The strains had the capacity of producing all or some of the above-mentioned virulence markers, to varying degrees though none of the strains produced any capsule. The strains also bound specifically to human intestinal cells in vitro with maximum adhesion levels of 30 bacteria/cell. The results on binding of V. vulnificus cytotoxin to HeLa cells, showed that a very short exposure time (30 min) was required for inducing the cytotoxic effects. V. vulnificus is a relatively new addition to the list of bacteria pathogenic for humans, and since there are increasing reports on its isolation from aquatic environments and seafood (e.g. raw oysters, crabs and shellfish), the results on virulence profiles of V. vulnificus strains presented above emphasize the importance of these organisms in public health and epidemiological studies.

Animals↗

PubMed1990

Reports of clinical hepatitis A from Public Health and hospital microbiology laboratories to the PHLS Communicable Disease Surveillance Centre during the period 1980-1988.

Clinical hepatitis, diagnosed as being caused by virus type A by tests for specific immunoglobulin M, has been reported from laboratories in England, Wales and Ireland since 1980. There were 25541 reports in the following 9 years, a yearly average of 2838. A 7-year cycle is suggested by peaks in the numbers of reports of 4502 in 1982 and 4167 in 1988 with a continuing rise in 1989. Contact with other cases of acute hepatitis was recorded for 3899 patients (15%) of which 2497 (64%) were in families, 258 (7%) were in schools, 94 (2%) were in institutions/hospitals, 197 (5%) were in the neighbourhood, while 140 (4%) were contacts at work or socially. A possible food source was recorded for 122 (3%) with shellfish being specified in 56 cases. Recent travel abroad was reported for 3692 patients (15%) of whom 3027 (82%) had visited areas of high prevalence for hepatitis A. About half of them had been to the Indian sub-continent, in strong contrast to visits abroad by the general population each year of which only 7% of the 22 million visits are to areas of high prevalence for hepatitis A. Association with the Indian sub-continent was particularly high for children.

Disease Outbreaks↗

PubMed1982

Techniques for virus detection in aquatic sediments.

Laboratory experiments have been undertaken to study the adsorption-desorption of poliovirus to and from marine and freshwater sediments. It was observed that marine sediments retained 99% of added virus, whereas, freshwater sediments adsorbed approximately 40% of the added virus. Ten eluents were investigated for their ability to desorb viruses from a marine sediment. It was found that virus elution from the marine sediment was relatively low and ranged from less than 1% to 44%. Two eluents, urea-lysine and TCA-glycine at pH 9.0, were found to be the most efficient among the eluents tested. Viruses were more easily released from freshwater than from marine sediments. When urea-lysine, beef extract and purified casein were used as eluents, the overall virus recovery ranged from 8% to 22% for the marine sediment and from 23% to 59% for the freshwater sediments. The urea-lysine methods was used for the detection of indigenous enteroviruses in sediments from a closed shellfish bed. Enteroviruses were recovered with concentrations up to 708 TCID50/50 g of sediment.

Adsorption↗

PubMed1988

A simple planimetric method to quantify cytotoxicity in cell culture monolayers.

Planimetry was shown to be a rapid, simple and reproducible method to quantify gross cytotoxicity in cell culture monolayers. A shellfish extract prepared from blue mussels (Mytilus edulis) was cytotoxic to Buffalo green monkey kidney cells. Exposure of cells to mussel extracts for 1, 2 and greater than or equal to 4 h followed by agar (plaque assay) overlays produced 34, 87, and 100% destruction of the monolayers, respectively, within 72 h. Planigraphs, prepared from tracing areas of cytotoxicity onto sheets of paper, served as permanent records of toxicity which were easily measured by planimeter experienced and nonexperienced scientists. Planimetric procedures may have utility in measuring biological and chemical toxicity as well as physiological stress in cell monolayers.

Animals↗

PubMed1993

A new method of RNA preparation for detection of hepatitis A virus in environmental samples by the polymerase chain reaction.

A new method based on RNA preparation from shellfish by polyethylene glycol (PEG) precipitation and trichloroacetic acid (TCA) extraction was developed for the detection of hepatitis A virus (HAV) by the polymerase chain reaction (PCR). The extraction provides high yield and the extracted RNA is undegraded. This method proved to be particularly useful for detection of RNA viruses from environmental samples by PCR.

Animals↗

PubMed1991

Behavior of Aeromonas species at refrigeration temperatures.

The ability of many strains of Aeromonas hydrophila and A. sobria to produce several types of virulence factors has been documented. The presence of Aeromonas in drinking water, as well as in river and saline waters and on various finfish and shellfish taken from them, has caused some concern relative to the role this bacterium plays as a causative agent of human gastroenteritis. The fairly common occurrence of Aeromonas on red meats, poultry and fresh produce and its ability to grow at 4 degrees C gives rise to further concern over public health risks which may be associated with consumption of these foods. A brief overview of the behavior of Aeromonas species at refrigeration temperatures is presented.

Aeromonas↗

PubMed1991

Campylobacter: pathogenicity and significance in foods.

In the last 10 years Campylobacter jejuni has emerged as the most frequent cause of bacterial gastroenteritis in man. Acute enterocolitis, the most common presentation of C. jejuni infection, can affect persons of all ages. C. jejuni has been found in virtually every country where investigations have been carried out. The frequent finding of dysenteric stools suggests that mucosal damage due to an invasive process analogous to that seen in shigellosis is important in the pathogenesis. Campylobacteriosis in man is mainly a foodborne infection in which foods of animal origin, particularly poultry, play an important role. Epidemiological investigations have demonstrated a significant correlation between the handling and consumption of poultry meat and the occurrence of Campylobacter enteritis. Barbecues appear to present special hazards for infection, because they permit easy transfer of bacteria from raw meats to hands and other foods and from these to the mouth. Milk is sometimes found to be contaminated and consumption of raw milk has caused several outbreaks of campylobacteriosis. Campylobacter can remain viable in fresh cheese for only a short period of time. The organism is also found in shellfish, such as clams. Campylobacter is probably very vulnerable to factors such as high temperatures and dry environments, and also to the presence of oxygen in atmospheric concentrations. Therefore, it is assumed that the organism does not persist in products like pelleted feed, meals, egg powder and spices, which are often contaminated by Salmonella. A number of preventive measures on different levels, taken simultaneously, are needed to reduce the incidence of campylobacteriosis in man.

Animals↗

PubMed1993

Survey of butyltin contamination in Portuguese coastal environments.

Butyltin compounds (MBT, DBT and TBT) in intertidal sediments collected in four different Portuguese coastal environments have been measured in order to evaluate the extent of contamination. The sites chosen were the Rias of Aveiro and Faro, and the Sado and Tejo estuaries. These zones were traditional areas for shellfish production in the recent past, but the effects of industrial development have caused a deterioration of the environment. Specific contaminations were derived from the harbour (commercial and/or fisheries) and shipyard activities, resulting in a release of TBT and causing the oyster populations of the above mentioned estuaries to almost disappear. Results presented in this study give a survey of TBT contamination levels found in the four areas. The paper discusses the importance of the pollution in comparison with other European coastal areas.

Journal Article↗

PubMed1996

Variability of cadmium, copper and zinc levels in molluscs and associated sediments from Chile.

The concentrations of cadmium, copper and zinc in mussel and sediment samples collected together from eight different geographical coastal areas of Chile were determined. The mussels studied were 'Chorito Maico', 'Almejas' and 'Navajuelas Chilenas' (Perumytilus purpuratus, Semelle solida and Tagellus dombeii, respectively). Sampling was carried out in July and September 1992 and January and April 1993 (winter, spring, summer and autumn seasons in Chile, respectively). The metal levels in these mussels varied among species; there were several sites where the metal concentrations in molluscs approached or exceeded the criteria levels for Cd, Cu and Zn in shellfish products: 1, 10 and 50 ppm ww respectively, which are regarded as safe levels for human consumption. The results of metal levels in sediments showed two areas clearly polluted with Cu. Strong relationships between Cu concentrations in the three molluscs and sediments were found; weak correlations were observed for Zn in S. solida.

Journal Article↗