Shellfish arsenic

Reinke, J., J.F. Uthe, H.C. Freeman, and J.R. Johnston. 1975. The determination of arsenite and arsenate ions in fish and shellfish by selective extraction and polarography. Environ. Lett. 8 371-380. 

Arsenic occurs naturally and is also used in insecticides. It is found in tobacco, shellfish, drinking water, and in the air in some locations. The standard allows for 0.05 mg of arsenic per liter of water. If persons drink water that continuously exceeds the standard by a substantial amount over a lifetime, they may suffer from fatigue and loss of energy. Extremely high levels can cause poisoning. 

Despite its availability and current use, coal is not as widely used today as the other fossil fuels. Coal s major weakness is that it does not burn cleanly. It often contains trace amounts of other elements, including mercury, arsenic, and sulfur, and when it burns, it releases these toxic substances into the air. Over time, coal pollution builds up in the environment. Mercury released during coal combustion, for example, settles in water and builds up in the bodies of fish and shellfish. When these fish and shellfish are eaten by humans and other animals, harmful amounts of mercury can be ingested. In 2008, bluefm tuna served in expensive New York restaurants was found to contain unacceptably high levels of mercury. These fish eat smaller organisms in the ocean, and when these small organisms contain mercury, the toxic element becomes concentrated in the body of the tuna. 

Fish are known to accumulate arsenic and a study carried out in 1998 found appreciable quantities of total arsenic in all samples analysed.15 The mean concentration of arsenic in samples of fresh marine fish landed in UK ports in 1995-1997 ranged between 1.9 mg/kg and 8.4 mg/kg. An earlier survey found that fish that live on or close to the sea bed, such as plaice, dabs, flounders and skate, tend to have higher levels of arsenic than other fish,24 and this was confirmed by the later work, where the highest level was found in plaice. Arsenic levels in shellfish show more variation, ranging from 1.3 mg/kg to 30 mg/kg. High levels are frequently found in crab, in which the white meat generally contains more arsenic than the brown meat. Lobsters contained similar levels of arsenic to crabs, with the highest levels found in pink shrimps. 

Although arsenic is very widely distributed in the environment, humans are exposed to low levels of this element. Although human exposure to arsenic can come through food, water, and air, the largest source of arsenic intake (approximately 25-50 11.g/clay) is from food. Some edible fish and shellfish do contain elevated levels of arsenic, but this is predominantly in an organic form ( fish arsenic ). Humans are exposed to levels of arsenic in different situations.22 For instance ... 

J. Brooke, W. H. Evans, Determination of total inorganic arsenic in fish, shellfish and fish products, Analyst, 106 (1981), 514-520. 

Arsenolipids such as 56-59 were detected in all of the extracted algae samples (1.5-33.8 pg/g dry wt) and fish samples (0.018-0.78 pg/g wet wt). Arsenobetaine 54 was detected in all of the extracted fish and shellfish samples (0.025-6.604 pg/g wet wt). A major share of arsenic components in seafood was organic arsenic with a low toxicity [146]. 

Contaminated water, food containing residue of arsenic pesticides, and veterinary drug fish and shellfish are the richest sources of organic compounds arsenobetaine and arsenocholine... 

Qcarashi, A., K. Sasaki, M. Toyoda, and Y. Saito. 1996. Annual d y intakes of Hg, PCB and arsenic from frsh and shellfish and comparative siuvey of their residue levels in fish by body weight, [in J )anese]. Eisei Shikenjo Hokoku (114) 43-47. 

Though the production of the poisoned dart gun created a sensation, other witnesses were to follow Colby who would describe many other devices. There were, it appeared, weapons which could be used to contaminate roads or railway tracks with biological agents, pens which would fire poison darts or spray gas into a room, umbrellas and walking sticks which would do the same. In fact the shellfish toxin represented only a tiny part of the arsenal which had been developed to wage clandestine chemical and biological warfare. 

Total arsenic levels in urine and blood reflect the metabolites As ", As", MMA and DMA accessible to direct analysis (see Section 6.3.2.3), as well as the chemically stable trimethylated forms, arsenobetaine and arsenocholine from fish or shellfish, which can increase after fish consumption... 

Topical application can provide local anesthesia and restrict bleeding The consumption of shellfish harvested during a red tide (due to a large population of a di-nollagellate species) is not recommended. This is because the shellfish are likely to contain (A) Arsenic... 

Most dietary arsenic originates from fish, shellfish, and seaweed products. On the basis of the U.S. Food and Drug Administtation (FDA) Total Diet Study for Market Baskets collected from 1990 through 1991, Adams et al. (54) estimated that food conttibuted 93% of the total daily intake of arsenic, with seafood accounting for 90%. The major arsenic species found in the fish and shellfish that are usually eaten is arsenobetaine (AB), a ubiquitous major arsenic species... 

Arsenic is abundant in seafood. Arsenobetaine is the major arsenic species present in fish and shellfish. Arsenosugars are the dominant arsenic species in seaweed. Both arsenobetaine and arsenosugars are present in mollusks (bivalves and gastropods) at comparable concentrations. Smaller amounts of arsenocholine, trimethylarsine oxide, tetramethylarsonium ion, DMA(V), MMA(V), inorganic arsenic, and unidentified arsenicals have also been found in seafood. Much less is known about the arsenic species in other food we eat. 

Fish and shellfish can accumulate arsenic, but the arsenic in fish is mostly in a form that is not harmful. 

Arsenic occurs naturally in small amounts in many foods. Shrimp, for example, contain about 19 parts per million (ppm) arsenic, and corn may contain 0.4 ppm arsenic. The amount of naturally occurring arsenic in foods depends on the surroundings where they are grown and the metabolism of the plant or animal. While many soils contain arsenic, which causes an accumulation of the element as a plant grows, some insecticides also contain arsenic, which causes an arsenic residue when the insecticide is applied. The U.S. Food and Drug Administration (FDA) has set a limit of 76 ppm for arsenic levels in shellfish. In its ionic forms, arsenic is much more toxic than in its covalently bound compounds. The typical toxic arsenic compounds contain ions such as arsenate (AsO ) or arsenite (AsOg). 

Speciation of compounds of environmental concern is another important application of coupled GC-ICP-MS and LC-ICP-MS. Arsenic compounds in shellfish are one example of the importance... 

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