Combustion, lead contamination

Lead contamination of soil is a result of introduction of trilead tetroxide, present in petrol and combustion gas. Lead may also be released from incorrectly enameled plates and old plumbing (Galal-Gorchev, 1993). Lead may accumulate in vegetables, fruit, and herbs. About 50% of the lead intake of children and 20% of intake by adults is absorbed from the gastrointestinal tract. It is distributed through the human body via the bloodstream and is... 

A large number of polycyclic aromatic hydrocarbons are known. Many have been synthesized in the laboratory, and several of the others are products of combustion. Benzo[a]pyrene, for example, is present in tobacco smoke, contaminates food cooked on barbecue grills, and collects in the soot of chimneys. Benzo[a]pyrene is a carcinogen (a cancer-causing substance). It is converted in the liver to an epoxy diol that can induce mutations leading to the uncontrolled growth of certain cells. 

The conditions imposed on oils by compressors - particularly by the piston type - are remarkably similar to those imposed by internal combustion engines. One major difference is, of course, that in a compressor no fuel or products of combustion are present to find their way into the oil. Other contaminants are broadly similar. Among these are moisture, airborne dirt, carbon and the products of the oil s oxidation. Unless steps are taken to combat them, all these pollutants have the effect of shortening the life of both the oil and the compressor, and may even lead to fires and explosions. 

Atmospheric contaminants from smelting works or combustion processes eventually enter the natural drainage system as fall out, and are carried into the rivers. It is probable that the deposition of sediments and the higher pH of marine water, which leads to precipitation, results in a build-up of the heavy metal pollutants in the river estuary. An assessment of this build-up is essentially an analytical problem. 

T. C. Ho and co-workers, "Metal Capture During Fluidized Bed Incineration of Wastes Contaminated with Lead Chloride," presented at the Second International Congress on Toxic Combustion By-Products Formation and Control, Salt Lake City, Utah, Mar. 26-29,1991. 

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