Cumulative poisons

Care must be used in handling lead as it is a cumulative poison. Environmental concerns with lead poisoning has resulted in a national program to eliminate the lead in gasoline. 

Lead and its compounds are cumulative poisons and should be handled with recommended precautions. These materials should not be used in contact with food and other substances that may be ingested (see also Lead compounds). 

Mercury is used in the manufacture of thermometers, barometers and switchgear, and in the production of amalgams with copper, tin, silver and gold, and of solders. A major use in the chemical industry is in the production of a host of mercury compounds and in mercury cells for the generation of chlorine. Mercury has a significant vapour pressure at ambient temperature and is a cumulative poison. 

Lead pipes The corrosion resistance of lead is generally excellent, but it is attacked by certain waters. This is usually of little significance so far as deterioration of the pipe is concerned, but is important because of danger to health, since lead is a cumulative poison even very small doses taken over long periods can produce lead poisoning. It is for this reason that its use for carrying potable water has been discontinued. 

CAUTION. Mercury vapour is a cumulative poison. All vessels containing mercury should be stoppered. Any spilled mercury should be immediately collected and placed in a flask containing water, and the bench (floor) dusted with powdered sulphur. Employ a tray under all vessels containing mercury and for all operations involving the transfer of mercury. 

Methanol is a dangerous fire hazard when exposed to heat or flame, and a moderate expl hazard when exposed to flame. It is a dangerous disaster hazard upon exposure to heat or flame, and can react vigorously with oxidizing materials. Methanol possesses distinct narcotic props, and is also a slight irritant to the mucous membranes. Its main toxic effect is exerted upon the nervous system, particularly the optic nerves and possibly the retinae. In the body the products formed by its oxidn are formaldehyde and formic acid, both of which are toxic. Because of the slowness with which it is eliminated, methanol should be regarded as a cumulative poison (Ref 5)... 

Symptoms appear much more slowly from skin absorption. Skin absorption great enough to cause death may occur in 1-2 h. Respiratory lethal dosages kill in 1-10 min, and liquid in the eye kills nearly as rapidly. Very small skin dosages sometimes cause local sweating and tremors but little other effects. Nerve agents are cumulative poisons. Repeated exposure to low concentrations, if not too far apart, will produce symptoms. 

Biological half times of cadmium in humans is lengthy. Based on body burden and excretion data, cadmium may remain in the human body for 13 to 47 years. Although cadmium is excreted primarily in urine and feces, it tends to increase in concentration with the age of the organism and eventually acts as a cumulative poison (Hammons et al. 1978). These phenomena have not been documented adequately in wildlife species. 

HN-3 is similar to HN-1 and HN-2, in that it is a cumulative poison that is highly irritating to the eyes and throat. Permanent corneal damage can occur from vapor exposure alone at concentrations around 200 mg/min/m3. HN-3 does not create sufficient vapor density to cause rash and blistering from a single exposure. Blistering may result from contact with the liquid form, multiple or persistent vapor exposure, or vapor condensation in sweat. A rash will develop from contact with liquid within approximately 1 hour, followed by blistering 6 to 12 hours later. Toxic effects on the eyes are immediate. 

Cumulative poison Highly irritating to eyes and throat Skin rash followed by blistering Degradation of blood oxidase function Lesions in small intestine Degenerative changes to mucous membranes... 

Arsine (SA) Inhalation Cumulative poison No known antidotes... 

The official compendia lay a great deal of emphasis on the control of physiologically dangerous, cumulative poisonous and harmful impurities, such as lead, arsenic and iron present in a host of pharmaceutical chemicals. These impurities very often creep into the final product through a number of means stated below, namely ... 

Mercury can be a cumulative poison, which means that minor amounts absorbed over long periods of time build up until damage to internal organs occurs. Years ago, a mercury compound was used in the manufacturing process of felt hats. Workers who came in contact with the mercury developed a variety of medical problems, including the loss of hair and teeth and loss of memory along with general deterioration of the nervous and other systems. This became known as the mad as a hatter syndrome because of the afflicted individuals odd behavior. 

Pb is highly toxic by inhalation of dust or fumes. Tolerance 0.2mg/cc in air. A cumulative poison, FDA regulations require zero Pb content in foods (Refs 3 4)... 

Very toxic to most plants cumulative poison in mammals. Inhibits 6-aimnolevulinate dehydra se and thus hemoglobin synthesis in mammals (see Al). One of the symptoms of lead poisoning is anemia. Toxic to central nervous system. 

Cadmium Weak evidence for ultratrace essentiality in rats.7 Moderately toxic to all organisms a cumulative poison in mammals, causing renal failure possibly linked with hypertension in man. Has caused serous disease f ita] itai") in Japan from pollution. May also pose pollution problem associated with industrial use of zinc, e.g., galvanization. 

Mercury None known. Very toxic to fungi and green plants, and to mammals if in sulubie form a cumulative poison in mammals. Serious pollution problems from use of orgartomer-curials as fungicides and from industrial uses of mer-... 

Lead compounds. These are powerful cumulative poisons and ingestion of even small amounts must be guarded against. Organic lead compounds (e.g. lead tetra-ethyl) are volatile and inhalation of their vapours must be avoided they are also dangerous by skin absorption. 

Cadmium is a highly cumulative poison with a biologic half-life estimated at about 20 to 30 years in humans. About half of the body burden of cadmium is found in the liver and kidneys. The total body burden reaches a plateau in humans around age 50. Cigarette smoke is a source of cadmium, and the body burden of cadmium is about 1.5 to 2 times greater in smokers than in nonsmokers of the same age. 

What is a cumulative poison In what sense is cadmium a cumulative poison What might be a metabolic explanation for why a poison is cumulative ... 

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