Seafood contaminated

Characteristics of human diseases and conditions caused by eating seafood contaminated with phycotoxins. 

Ahmed, F., Review assessing and managing risk due to consumption of seafood contaminated with microorganisms, parasites, and natural toxins in the US, Int. J. Food Sci. TechnoL, 27, 243, 1992. 

Spores may be transferred from soil and plants to the sea via rainwater, causing the prevalence in coastal waters of the same C. botulinum types as on the land. Such a correlation was observed in Great Britain, where the type B predominates both in soil and in bottom sediments. Similarly, 71% of fish and bottom-sediment samples collected in southern France were contaminated with type B, while C. botulinum type E was found only in 9.6% of samples (Each et al., 2002). However, it is commonly believed that non-proteolytic type E is characteristic for the marine environment. A distinguishing feature of type E strains is the ability to grow in low temperatures (about 3°C), which are typical for bottom layers of seas and oceans. Moreover, the bottom sediments provide anaerobic conditions for the outgrowth of Clostridium. Therefore, the marine environment promotes C. botulinum type E distribution. This has been further supported by the rate of fish and seafood contamination fish and seafood isolated in many countries are most frequently contaminated with C. botulinum type E (Dodds, 1993 a,b). Furthermore, epidemiological studies have shown that the majority of botulism cases linked to fish and seafood consumption reported between 1950 and 1996 in the U.S. were caused by C. botulinum type E (Centers for Disease Control and Prevention 1998). C. botulinum type F,... 

Kurland, L.T., Farro, S.N. and Siedler, H. (1960) Minamata disease. The outbreak of a neurologic order in Minamata, Japan and its relationship to the ingestion of seafood contaminated by mercuric compounds. World Neurol., I, 370-395. 

EXPOSURE ROUTES outdoor air soil food fish and other seafood contaminated water fanners and pesticide applicators exposed inhalation skin adsorption eye and skin contact... 

A number of human illnesses are caused by ingesting seafood contaminated with toxins produced by marine phytoplankton [9-11], The phytoplankton is the base of the marine food web, and the toxins it produces can accumulate and concentrate in higher organisms that can become lethal if ingested. Although mainly neurotoxins, these toxins can cause a wide range of acute and chronic health effects in humans and other species. They are tasteless, odorless, and heat and acid stable. Therefore, conventional food methods are unable to detect and destroy them in contaminated seafood. 

VOCs also can migrate from the atmosphere to water systems via precipitation, fallout, or absorption into surface waters. Aquatic VOCs taint seafood, contaminate drinking water, and can be toxic to aquatic life. Moreover, VOCs can penetrate into the soil, where they can injure plant life and inhibit microorganisms responsible for soil fertility (2). 

The toxicity of mercury was tragically illustrated in the Minamata Bay area of Japan during the period 1953-1960. A total of 111 cases of mercury poisoning and 43 deaths were reported among people who had consumed seafood from the bay that had been contaminated with mercury waste that drained into Minamata Bay from a chemical plant. Congenital defects were observed in 19 babies whose mothers had consumed seafood contaminated with mercury. The level of metal in the contaminated seafood was 5-20 parts per million. 

Kalaitzis, J.A., Chau, R., Kohli, G.S., Murray, S.A, and Neilan, BA (2010) Biosynthesis of toxic naturaDy-occurring seafood contaminants. Toxicon, 56, 244—258. 

Direct poiitt-source discharges To surface water No quantitative assessment available. Only ingestion of contaminated seafood was considered. 

Cholera, the first reportable disease, is endemic in South Asia, particularly in the Ganges delta region.2 The biotypes of Vibrio cholerae responsible for pandemics are serogroup 01 (El Tor) and serogroup 0139.16,17 Cholera can be transmitted by water or by food contaminated with contaminated water, particularly undercooked seafood. V. cholerae grows well in warm temperatures, causing marked seasonality in the incidence of cholera.2... 

INTEGRATED STUDIES Adriatic Sea mercury-contaminated area vs. reference site various seafood products of commerce edible portions ... 

In Hong Kong, limited to <6 mg As+3/kg FW for edible tissues of finfish and <10 mg As +3/kg for molluscs and crustaceans (Phillips etal. 1982 Edmonds and Francesconi 1993) in Yugoslavia, these values are 2 for fish and 4 for molluscs and crustaceans (Ozretic etal. 1990) in Australia, <1 mg inorganic As/kg FW and in New Zealand <2 mg inorganic As/kg FW — there is no limit on organoarsenicals (Edmonds and Francesconi 1993). In the UK, seafood products should contain <1 mg As/kg FW contributed as a result of contamination (Edmonds and Francesconi 1993)... 

The paralytic shellfish toxins (PSTs Fig. 5.2a) include saxitoxin (STX) as well as STX analogs such as neo-saxitoxin (neo-STX), gonyautoxin (GTX), and the decar-bamoyltoxins (Sivonen and Jones 1999). These molecules are of particular concern in marine systems, where they have been implicated in human deaths following the consumption of contaminated seafood (Van Dolah 2000). The causative agents in those cases are several genera of marine dinoflagellates that are common components of red tides (e.g., Alexandrium sp. Homer et al. 1997 Van Dolah 2000). 

These potent natural toxins are tasteless and odorless, and contaminated seafood appears to be completely normal. They are not destroyed by cooking or by food preservation (e.g., freezing, drying, or salting). In addition, these toxins are refractory to the action of human digestive enzymes, and there are no antidotes against their biological activity (Schantz, 1973). 

Some evidence exists that HABs are now occurring more frequently and over a wider geographic area than in the past (Epstein et ah, 1994 Halstead et ah, 1994 Tester, 1994 Todd, 1994 Viviani, 1992). Phycotoxin contamination of seafood is therefore a challenge for those people responsible for ensuring seafood quality and has important implications for public health (including nutrition and medical care). 

AZP, the most-recently characterized marine seafood poisoning, is associated with eating shellfish contaminated with azaspiracids. The first human intoxications attributed to AZP occurred in the Netherlands, and the symptoms included those similar to DSP (i.e., nausea, vomiting, severe diarrhea, and stomach cramps). However, although chemical analyses did not identify significant levels of the diarrhetic shellfish poisons, they identified a new class of toxins (James et ah, 2003a). 

In general, the clinical presentation of the human diseases associated with the ingestion of marine seafood toxins is similar to that of any other food poisoning disease. However, a number of clinical issues make these diseases particularly difficult to diagnose and treat. For example, the neurotoxic syndromes associated with CFP, PSP, and NSP represent points along a continuum of disease severity rather than clinically exclusive diseases. Even if fish or other seafood is the suspected source of a disease outbreak, diarrhea associated with the outbreak could be misdiagnosed as originating from bacterial rather than from phycotoxin contamination. 

Diseases associated with marine seafood toxins appear to have high attack rates. An attack rate is the proportion of a well-defined population that develops a disease over a specific period of time (where the numerator is the number of new cases during that period and the denominator is the size of the population at risk, e.g., the number of people who ate a contaminated food at the start of the time period of interest) (Goodman and Peavy, 1996). Physicians therefore need to ask about disease cases among people sharing the same seafood meal. 

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