Spontaneous combustion, human

Consider the phenomenon referred to as spontaneous human combustion (SHC), as publicized from time to time (e.g., as was reported in Arthur C. Clarke s Mysterious Universe, shown on the Discovery Channel, for instance, on October 22,1996, and was mentioned in Charles Dickens Bleak House). If this weird phenomenon does indeed occur, it could instead be referred to as spontaneous ignition, followed by combustion. And if it is at least conceivable for aberrations to occur among the enzyme-catalyzed reactions involved in the metabolism of glucose or other carbohydrates to yield CO2 and H2O, then conceivably there may be a case. Ordinarily, body metabolism reaction rates are miniscule as compared to the direct combustion or combustive oxidation of conventional fuels. If enzyme promoters exist, however, there is the possibility that runaway metabolic processes occur, similar to those in the ignition and further combustion of carbonaceous materials. If so, ample air or oxygen supply would also be required for this extremely unlikely scenario. 

The discovery in 1993 that both phosphine and diphosphine could be produced in faeces by bioreduction processes offered a possible explanation of legendary spontaneous human combustion [15,15a]. (The fire from the mythological dragon could perhaps be explained on the same basis ) Some doubts have, however, been raised about earlier reports of bioreduction. Energy requirements for some processes, for example, PH3 formation from phosphite, may be unfavourable [17]. 

One of the more persistent urban myths of forensic science is the belief that the human body can somehow erupt into flame and rapidly burn down to ashes with no discernible ignition source and nearly no peripheral burning. The material discussed in Chapter 9 concerning heat and mass transfer, fuel-air ratios, flammability limits, and the conditions that must be met for successful ignition are sufficient to debunk any ideas of spontaneous human combustion, but the myth persists. 

Rain unaffected by human activity contains mostly weak acids and has a pH of 5.7. The primary acid present is carbonic acid, H2C03, a weak acid that results when atmospheric carbon dioxide dissolves in water. The major pollutants in acid rain are strong acids that arise from human activities. Atmospheric nitrogen and oxygen can react to form NO, but the endothermic reaction is spontaneous only at the high temperatures of automobile internal combustion engines and electrical power stations ... 

OSHA PEL TWA 0.5 mg(Ba)/m3 ACGIH TLV TWA 0.5 mg(Ba)/m3 Not Classifiable as a Human Carcinogen DFG MAK 0.5 mg(Ba)/m3 DOT CLASSIFICATION 6.1 Label KEEP AWAY FROM FOOD SAFETY PROFILE A poison via subcutaneous route. See also BARIUM COMPOUNDS (soluble). Combustible by spontaneous chemical reaction produces heat on contact with water or steam. Reacts with H2O, Ba(OH)2. Incompatible with H2S, hydroxylamine, N2O4, triuranium octaoxide, SO3. 

Human mutation data reported. Questionable carcinogen with experimental tumorigenic data. Moderate fire hazard by spontaneous chemical reaction in contact with reducing agents. It ignites readily and burns rapidly. A powerful oxidizer. Dangerous explosion hazard may explode spontaneously when heated to above melting point, or when overheated under confinement. It is moderately sensitive to heat, shock, friction, or contact with combustible materials. Explosive decomposition above the mp (103°) forms flammable products. 

SAFETY PROFILE An allergen. A human skin and eye irritant. Combustible when exposed to heat. Spontaneous heating may occur. To fight fire, use CO2, dry chemical, fog, mist. See also CASTOR BEAN. 

Caution. Fluorine presents some, though not an extreme, hazard because of its toxicity. It ignites combustible materials spontaneously and may start laboratory fires. Wa.ste fluorine from the reaction should be discharged into a hood, and the waste vent should not be close to materials which will burn. Fluorine in high concentration burns human skin. The burn seems to be caused at least as much by heat as by the hydrogen fluoride produced by the reaction. 

The human body is a remarkably efficient organism that is able to reduce the amount of waste and ensure that energy liberated in one part of a biochemical reaction is actually used up, or stored, in another part of such a reaction. This means that we exist more or less at steady state giving out very little surplus energy. In fact, the amount of heat that we lose is equivalent to less than that of an electric light bulb. Less efficient organisms lose a great deal of heat and, hence, one sees spontaneous combustion of farmers haystacks because of bacterial inefficiency en masse. 

Notwithstanding its deficiencies as an incendiary, phosphorus has a certain tactical value because of the power of obscuration caused by the volatility of its final combustion product, phosphorus pentoxide (PgOs), the spontaneous re-ignitibility of doused, unburned residues, and the severity of the wounds caused by burning phosphorus when it comes in contact with human skin. Its burning properties can be improved by mixing it with synthetic (GRS) rubber, a mixture called plasticized white phosphorus (PWP). ... 

Properties Wh. to yish.-wh. amorphous waxy solid, tallow-like odor and taste very si. sol. in water sol. in alcohol, ether, acetone, CCI, m.w. 284.47 dens. 0.847 (70 C) m.p. 69.3 C b.p. 383 C acid no. 195-200 iodine no. 4 max. flash pt. (CC) 385 F ref. index 1.4299 (80 C) Toxicology LD50 (IV, rat) 21.5 1.8 mg/kg poison by IV route human skin irritant possible sensitizer for allergic persons questionable carcinogen exjKrimental tumorigen by implant TSCA listed Precaution Combustible when exposed to heat or flame heals spontaneously... 

Some apparently authentic cases of the spontaneous combustion of living human bodies (particularly females addicted to alcohol) were described. Some genuine causes of spontaneous combustion of non-living materials were described by Bartholdi. Liebig attacked the belief in the spontaneous combustion of persons addicted to alcohol, a case of which was reported in Darmstadt. 

Applying the Science 10.1 Spontaneous Combustion Human Candles... 

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