Common Poisons

Carbon monoxide, CO, is one of the most common poisons. Any carbon-containing substance will produce carbon dioxide CO as one of the ultimate products when burned. In our body as well, carbon dioxide is produced as the final product when we metabolize our food. It is exhaled from the lungs, and is not chemically toxic. A high concentration of carbon dioxide in the atmosphere can cause asphyxia, as carbon dioxide cannot support respiration. But this is not due to the chemical toxicity of carbon dioxide. 

Cyanide is another widely known poison. Cyanide (CN ) usually comes in the form of potassium cyanide (KCN), sodium cyanide (NaCN), or hydrogen cyanide (HCN). The first two are white solid, and hydrogen cyanide is a pungent-smelling gas. Cyanide binds very strongly with a metal ion such as Fe(II), Fe(III), Cu(II), Zn(II), and many others. These ions constitute important portions, that is, the active sites of many enzymes and proteins (Chap. 6). When a cyanide ion binds with a metal ion, the enzyme s function is disrupted. Cyanide that enters into our body almost indiscriminately binds to any metal ions and disrupts their functions, but an especially sensitive place is the last enzyme in the whole series of respiratory chain. The enzyme contains both iron (embedded in the porphyrin as in hemoglobin) and copper. Cyanide binds to both iron and copper in this enzyme, and stops its function, the last step of respiration. What is the result It stops respiration hence it stops the production of bodily energy (ATP). As we talked about in Chap. 3, we need to continuously produce ATP. Otherwise, we would die. 

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An efficient, low temperature oxidation catalyst was developed based on highly disperse metal catalyst on nanostructured Ti02 support. Addition of dopants inhibits metal sintering and prevents catalyst deactivation. The nanostructured catalyst was formulated to tolerate common poisons found in environments such as halogen- and sulfur-containing compounds. The nanocatalyst is capable of oxidizing carbon monoxide and common VOCs to carbon dioxide and water at near ambient temperatures (25-50 °C). 

The AAPCC is a United States based organization of poison centers and interested individuals that coordinates information on common poisons. 

Vipers, Cobras and Kraits are the common poisonous snakes and in India 40,000 to 50,000 deaths recorded per year due to snake bite. 

TMS catalysts fell into a special category due to their exceptional resistance to poisons. In fact, the presence of sulfur compounds, the most common poison of metallic and oxide catalysts, does not decrease their catalytic activity, but is needed to maintain high activity. Sulfide catalysts are also very resistant to carbon deposition, which is illustrated by their use for converting residual oils. Arsenic, as well as nickel and vanadium contained in heavy petroleum fractions, are some of the few substances that cause significant deactivation, and this only occurs by physical blockage of pore structure in supported catalysts. 

Organic substances are obvious poisons for hydrogen evolution (inhibitors) [154], but the most common poisons for industrial cathodes are the metallic species present in solution as a result of corrosion of the cell hardware and of other components of the electrochemical reactor. As a matter of fact, the most common impurity is Fe coming from the steel employed in manufacturing cells, which can be cathodically deposited on the active layer [34, 155]. Other impurities which have been considered are Cr, Ni, Hg and Cu [156, 157], In other cases, and under different conditions, S [158-160] and CO [161] have also been considered as poisons for Pt. 

In circumstances where impurities in the hydrogen cause poisoning, the hydride can be reactivated by heating and evacuation. Oxygen, CO, and H2O are common poisons. 

Group 4 poisons should be checked as a matter of routine if vomiting and diarrhoea are noted as symptoms, no matter what other poisons may be suggested by medical opinion or circumstantial evidence. Although the Reinsch Test (p. 57) will detect only seven of the twenty potentially toxic metals, it can be applied to almost any material (body fluids, slmried tissue, food Mid (hinks) without Miy elaborate prepM ation, and it is sensitive enou to detect toxic concentrations of tiie most common poisonous metals in a few minutes. However, it misses too many metals for it to be considered as a complete group exclusion test. 

Sulphur Poisoning. Sulphur is the most common poison for steam reforming catalysts. Sulphur is a natural component of all hydrocarbon feedstocks, but the sulphur contents of the feed is reduced to a few ppb by hydro-desulphurization followed by absorption over zinc oxide. The remaining sulphur, normally below the analytical detection limit, will slowly poison the catalyst (7). The mechanisms of sulphur poisoning are described in detail in the literature 2,8), The sulphur compounds are chemisorbed dissociatively on the nickel surface equation 4. 

The routes of exposure to cephalosporins are commonly oral, intravenous, or intramuscular. Accidental ingestion of oral dosage forms by children is the most common poisoning exposure. 

Penicillin is available in tablet and suspension form for oral use and in injectable form for intravenous and intramuscular use. Ingestion of tablets and the suspension forms are the most common poisoning exposures. 

Dogs and cats are commonly poisoned by pesticides, herbicides, household products such as antifreeze, and drugs such as acetaminophen applied by humans to their pets. By far the most common toxicities in these small animals involve various insecticides and the overzealous use of these products by owners attempting to control fleas and ticks on their pets. 

An illustrated guide to some common poisonous plants in Nova Scotia including algae, fungi, and leafy plants. 

Poisons and raw materials for poison are rarely sold in stores, so an assassin who wants to be assured of pure ingredients must often go looking for them at the source. This can be as simple as a walk to the local greenhouse or a difficult break-ing-and- entering. It takes about 10 minutes per DC point of the poison to find a large enough amount of common poisonous materials to use, be it animal, vegetable, or mineral. 

Common catalyst poisons, such as H2S and HgClj, also decrease disproportionately the reduction rate of alkenes and the working electrode potential under potentiometric operation 34). Although CO is a common poison of noble metal catalysts, its effect is associated with a one-to-one exclusion of H atoms from the surface 12, p. 115) and not with extensive blockage of neighboring sites, usual with strong poisons. Other catalyst poisons, such as traces of metals Al, Zn, Ti, Cu, Mo, and Co 248), that can exist in reactants or arise from gas lines and cell housings, have received only sporadic attention to date. 

Kingsbury, J. M. (date ). Deadly Harvest — a Guide to Common Poisonous Plants, Holt, Rine-hart and Winston, NY, p. 58. 

The TPPTS catalyst system is not sensitive toward sulfur and most of the other common poisons for hydroformylation catalysts. One reason is the continuous withdrawal of organic and other by-products with the product phase and the vent stream from the decanter (see Figure 2), avoiding the accumulation of poisons in the catalyst solution. 

Kingsbury, J.M. 1965. Deadly Harvest A Guide to Common Poisonous Plants. New York Holt, Rinehart and Winston. 

During the evolution of European society, aspiring enemies or family routinely killed nobility with poisons. In order to avoid this demise, many nobles instituted two general procedures one, tasters who consumed some of the food prior to the nobility, and two, the gradual consumption of the common poisons of their time in an increasing dosage to build up tolerance and avoid death by poison. 

Another mode of deactivation is termed poisoning (see Figure 4), which results from a chemical reaction of a gaseous species with the active metal (or, alternatively, a strong chemisoiption bond). For example, under certain conditions sulfur can fonn a compound with some metals. Phosphorous, halogens, and lead are common poisons for noble metal catalysts. 

Mankind encountered the effects of carbon monoxide as far back as prehistoric times. It is the most common poison with a suffocation action. It is second to carbon dioxide with respect to the amounts of industrial emissions. Carbon monoxide toxicity is due to its affinity to haemoglobin. This affinity is higher by a factor of 200 than that of oxygen. Haemoglobin... 

Carbon monoxide is a colorless, odorless, tasteless, toxic gas. It is one of the most common poisons in the environment and is responsible for thousands of deaths and hospital emergency room visits each year in the United States. Carbon monoxide is produced from fuel-burning appliances, such as space heaters, furnaces, stoves, and vehicles. It is also a component of cigarette smoke. Carbon monoxide is flammable and capable of forming an explosive mixture with air. 

Tomer, N.J. and A.F. Szczawinski 1991. Common Poisonous Plants and Mushrooms of Mirth America. Timber Press, Portland, or. 

Mixed-metal Catalysts. Because an apparently small and inappreciable amount of substance might impair or poison the activity of a catalyst, strenuous efforts must be made to prepare the catalyst as nearly chemically pure as possible. It will usually be found that, in this state, activity is either nil or veiy low. The solution to this dilemma is to recognize more clearly the class of substances to which poisons and promoters belong. Catalyst poisons are usually substances that can react chemically with the catalyst or else, because of their volatility, can condense onto and blot out the active areas of the catalyst. The common poisons are halogens, sulfur, arsenic, and sometimes metals of low melting point such as mercuty, lead, and tin. 

In those cases where some of the more common poisons, such as sulfur, have to be tolerated, it is possible to utilize catalysts that contain sulfur. The molybdenum sulfides are examples of catalysts of this t3q)e. Under proper temperature and pressure conditions, these materials are effective hydrogenation catalysts. 

Verdcourt B, Trump E C (1969). Common Poisonous Plants of East Africa. Collins, London, p. 62. 

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