Hazardous organic matter

Hazardous Organic Matter in Municipal Sewage Sludge. 115... 

Cheng HF, Chen SY, Lin JG (2001) Hazardous organic matters in municipal sewage sludge in Taiwan. Water Sci Technol 44 65-70... 

Bromates represent a potential fire and explosion hazard if heated, subjected to shock, or acidified. They should not be allowed to contact reactive organic matter, including paper and wood. Industrial quantities are packed in fiber dmms with polyethylene liners or in metal dmms. Laboratory quantities are supphed in glass bottles. For shipment, a yellow oxidizer label is required under DOT regulations. 

Hydrogen sulfide is a commonly occurring decomposition product of organic matter. It is relatively water soluble at higher pHs where it is predominantly dissociated as and S ions. As the pH is decreased below 7, undissociated gas HjS begins to predominate and is released. Since its vapor density is > 1.0, HjS gas tends to settle in low places and creates a toxicity hazard. H S is readily oxidizable by a number of means to less toxic SO3" or 804 forms. 

The remaining processes, although they occur under near-surface and deep-well conditions, are less applicable to the latter. Distinct differences between the two environments, however, can lead to significant differences in how the processes affect a specific hazardous substance. Compared with the near-surface environment, the deep-well environment is characterized by higher temperatures, pressures, and salinity, and lower organic matter content and Eh (oxidation-reduction potential). 

Caution Chromates, including potassium and sodium dichromate, are hazardous materials, as are sulfuric and phosphoric acid used in the oxidation of soil organic matter. Great care must be exercised in using these chemicals and in disposing of the waste generated. 

In response to a statement [1] that alloys of 2 alkali-metals (Li-Na, K-Na) can be prepared in small amounts by beating the solid components together, without heating in the latter case, it was emphasised that the real hazard arises not from reaction of the surface coating of potassium superoxide with potassium, but with residues of oil or organic matter on the potassium which will explode under impaction with the superoxide [2] - [4]. 

The effect of humidity on combustibility of various mixtures of organic matter and sodium chlorate was studied. Addition of a proportion of hygroscopic material (calcium or magnesium chlorides) effectively reduces the hazard. Similar effects were found for sodium dichromate and barium chlorate. 

Incorporating allelopathy into agricultural management may reduce the use of herbicides, cause less pollution, and diminish autotoxic hazards. Authentic inhibitors isolated from plant material have been subjects for examination in, vitro, but attempts to compare their effects in soils are limited. Soils contain a heterogeneous collection of organic matter of various origins. 

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