Organic solvents toxicity

Disadvantages associated with some organic solvents include toxicity flammabiHty and explosion ha2ards sensitivity to moisture uptake, possibly leading to subsequent undesirable reactions with solutes low electrical conductivity relatively high cost and limited solubiHty of many solutes. In addition, the electrolyte system can degrade under the influence of an electric field, yielding undesirable materials such as polymers, chars, and products that interfere with deposition of the metal or alloy. 

AH volatile organic solvents are toxic to some degree. Excessive vapor inhalation of the volatile chloriaated solveats, and the central nervous system depression that results, is the greatest hazard for iadustrial use of these solvents. Proper protective equipment and operating procedures permit safe use of solvents such as methylene chloride, 1,1,1-trichloroethane, trichloroethylene, and tetrachloroethylene ia both cold and hot metal-cleaning operations. The toxicity of a solvent cannot be predicted from its chlorine content or chemical stmcture. For example, 1,1,1-trichloroethane is one of the least toxic metal-cleaning solvents and has a recommended threshold limit value (TLV) of 350 ppm. However, the 1,1,2-trichloroethane isomer is one of the more toxic chloriaated hydrocarboas, with a TLV of only 10 ppm. 

Poly(ethylene glycol) (PEG) is a polymer of considerable interest due to several properties, including solubility in both water and many organic solvents, non-toxicity and ability to induce cell fusion, and it has found many biological applications [59]. Despite its poor mechanical strength, attaching PEG chains onto mechanically strong materials, such as fibrils [60], is one way to harness its properties [61]. 

The results of the verification program showed that all organic toxic pollutants were reduced across biological treatment. Chloromethane, used as a solvent at plant 000005, was present at significant levels in treated effluent. 

In the traditional process, the dried and ground paprika is extracted by organic solvents (such as hexane, acetone, benzene, methylene chloride, or dichloroethane) which have low boiling points. These traditional processes have several disadvantages. Most organic solvents like benzene and the chlorinated solvents are toxic, and government food regulations dictate... 

MW 92.53 CAS [106-89-8] used to make epoxy resins, adhesives, surfactants, and plasticizers, and also as a solvent for gums, resins, and paints colorless liquid chloroform-like odor boils at 116°C solidifies at-57°C vapor pressure 12 torr at 20°C density 1.18 g/mL at 20°C moderately soluble in water (6.6% at 20°C), soluble in most organic solvents moderately toxic, carcinogenic, and a strong irritant (Patnaik, 1992). 

Synonyms isocyanic acid methyl ester, isocyanatomethane, MIC Formula CH3NCO MW 57.05 CAS [624-83-9] used in the manufacture of carbamate pesticides colorless liquid with an unpleasant odor boils at 39°C freezes at -80°C vapor pressure 400 torr at 20°C density 0.96 g/mL at 20°C vapor density 1.97 (air= 1) decomposes in water soluble in most organic solvents highly toxic and flammable. 

MW 174.16 CAS [584-84-9] used in the production of urethane foams, elastomers, and coatings also commercially available as a mixture of 2,4- and 2,6-isomers colorless liquid or solid turns dark on exposure to light pungent fruity odor boils at 238°C melts at 20.5°C (80 20 mixture of the isomers melts at 13°C) density 1.22 g/mL decomposes with water and alcohol soluble in most organic solvents highly toxic. 

In a fascinating chain of events, it is precisely these properties that also make organic solvents inherently toxic to humans. Upon exposure, there are primarily four factors that determine the substance s toxicity (Katzung 1995) ... 

Another very important green chemistry solvent is supercritical water (SCW) [14], Water under supercritical conditions is an extremely powerful oxidizing and cleansing agent that has been proven remarkably promising as a soil decontaminant by efficiently degrading persistent organic toxic wastes that are difficult to eliminate from polluted soils, and in the treatment of several types of industrial wastes such as textile and cellulose wastewater [2],... 

Organic solvents, which induce CYP2E1, are comprised of a few broad chemical classes, including hydrocarbons such as benzene and toluene, halogenated aliphatic compounds such as carbon tetrachloride and dichloroethane, aliphatic alcohols such as ethanol, and hydroxyethers such as 2-methoxyethanol. Industrial solvents are frequently mixtures of several compounds. The most frequent solvent-associated toxicity occurs from occupational exposure. A number of organic solvents have been examined for their effects on the immune system, and the requirement for their bioactivation to produce immunotoxicity has been well established. 

Different ion channels maintain the stability of excitable membranes that are necessary for normal functioning of the body. Saxitoxin, tetrodotoxin, and DDT all cause toxicity by blocking the sodium channel in excitable membranes. On the other hand, organic solvents cause toxicity by changing the membrane fluidity of the neurones in the central nervous system. 

Properties Crystalline solid. Almost insoluble in water soluble in common organic solvents. Hazard Toxic by ingestion, a cholinesterase inhibitor. 

Adamsit - crystal substance of yellow colour, weakly soluble in water, better soluble in organic solvents average toxic concentration -0,00038 mg/1. 

Problems Associated with the Preparation and Stabilization of a PAH-Water SRM. Preparation of aqueous PAH solutions of known concentration by gravimetric procedures is difficult because of the extremely low aqueous solubilities of PAH. As shown in Table IX many PAHs have aqueous solubilities of less than 500 /xg/kg (ppb). Preparation of aqueous solutions of known concentration by serial dilutions of a more concentrated organic solution is both hazardous and wasteful. After small aliquots are taken, large volumes of organic solvent containing toxic and expensive chemicals remain to be disposed of. 

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