Chemical intermediaries

Thus, carbohydrates act as the chemical intermediaries by which solar energy is stored and used to support life. 

Neurotransmitter Chemical intermediary in the nervous system that facilitates transmission of impulses across synapses. 

Table 4-2 lists the facilities in each state that manufacture or process chloroform, the intended use, and the range of maximum amounts of chloroform that are stored on site. The data listed in Table 4-2 are derived from the Toxics Release Inventory (TRI93 1995). Only plants from 3 states (associated with the 4 plants noted above) actually generate chloroform as an end-product for sale or distribution. In most cases, chloroform is a chemical intermediary, impurity, or waste by-product at the 172 facilities included in the TRI survey. Only certain types of facilities were required to report therefore, this is not an exhaustive list. In some cases, facility names are not available or numeric values for amounts of chloroform produced, stored, transferred, or released are missing. This complicates making comparisons between the TRI listings and information from other information sources. 

Butane occurs naturally in natural gas, where it is present to the extent of about 1 percent, and in petroleum, where it exists only in very small amounts. Butane is used primarily as a fuel and as a chemical intermediary, a compound used to produce other chemical substances. 

As a chemical intermediary in the production of a number of organic compounds. 

In the early twenty-first century, more than 95 percent of the isoprene produced is used to make -polyisoprene synthetic rubber. The remaining 5 percent is used to make other types of synthetic rubber and other kinds of polymers. A small amount of the compound is used as a chemical intermediary, a substance from which other organic chemicals is made. 

Chlorobenzenes are persistent and bioacciunulative chemieals that have been used as solvents and biocides, in the manufacture of dyes and as chemical intermediaries. The effects of exposure depend on the type of ehlorobenzene however, they eommonly affeet the liver, thyroid and central nervous system. Hexachlorobenzene (HCB), the most toxic and persistent chemieal of this group, is also a hormone disrupter. 

Carbohydrates are the chemical intermediaries by which carbon atoms from CO2 are incorporated into growing organisms and by which solar energy is stored and used to support life. Thus, carbohydrates are the biological starting point, and their metabolism is intimately interconnected with the metabolism of all other biomolecules. The catabolism of glucose, in fact, has been called the backbone of all metabolic pathways. 

The increasing use and transportation of toxic industrial chemicals around the world following the Second World War has been accompanied by a rise in the number of small- and large-scale accidental releases causing toxic trauma in the civil setting. The most devastating of this was in Bhopal in India in 1984 where the accidental release of 40 tons of methyl isocyanate, a chemical intermediary in the production of pesticide and other compounds in a densely populated urban area, led to more than 5000 fatalities. The important medical lessons from this incident are considered in Chap. 10. 

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