Inhalation toxicant, difficulty

Most general-purpose release agents have been developed for this market in part because of their low toxicity and chemical inertness and do not usually present health and safety problems. Some of the solvent dispersions require appropriate care in handling volatile solvents, and many supphers are offering water-based alternatives. Some of the sohds, particularly finely divided hydrophobic sohds, can also present inhalation problems. Some of the metallic soaps are toxic, although there is a trend away from the heavier, more toxic metals such as lead. The reactive type of release coating with monomers, prepolymers, and catalysts often presents specific handling difficulties. The potential user with health and safety questions is advised to consult the manufacturer directly. 

The toxic symptoms from inhalation of nickel carbonyl are beUeved to be caused by both nickel metal and carbon monoxide. In many acute cases the symptoms ate headache, di22iQess, nausea, vomiting, fever, and difficulty in breathing. If exposure is continued, unconsciousness follows with subsequent damage to vital organs and death. Iron pentacarbonyl produces symptoms similar to nickel carbonyl but is considered less toxic than nickel carbonyl. 

Another difficulty comes from the consideration of the route of entry (sf the contaminant, as chemicals can enter the body by various routes and the human body responds to the action of a toxic agent primarily on the basis of the rate and route of exposure. Without any doubt, the most important route of exposure at the workplace is inhalation, and this should be the route used to set OELs. However, if there is a threat of significant exposure by other routes, such as cutaneously (including mucous membranes and the eyes), either by contact with vapors or by direct skin contact w ith the substance, additional recommendations may be necessary. 

As is needed for all potential risks for chemical substances, an index of toxicity enables quantification of risk. Nevertheless, it only applies to risk by inhalation, which is yet the most common as well as insidious risk under normal working conditions with chemical substances. However, this approach should be treated with caution because of the difficulties inherent in toxicological risks. At this stage of the analysis it is essential to work in collaboration with the company doctor, whose total agreement is necessary. 

In summary, intratracheal instillation of CNTs has shown that their potential in eliciting adverse pulmonary effects is influenced by exposure time, CNT dose, CNT biopersistence, surface defects, and metal contamination [71, 72]. Despite the use of surfactants, all studies showed that intratracheal instillation caused major difficulties due to the agglomerative nature of CNTs in a biological environment. More realistic exposure methods, namely inhalation rather than intratracheal administration, are therefore needed for determining the pulmonary toxicity [59, 65, 73]. Several investigations have been performed by using administration different from intra-... 

Absorption intestine (50% children, 10% adults), inhalation Sensitive individuals fetus, children, and women of childbearing age Toxicity/symptoms developmental and nervous system, lowered IQ, memory and learning difficulties, behavioral problems Regulatory facts air - 0.5 mg/m3, drinking water 15 jo.g/1, not allowed in paint or automobile gasoline... 

Few neurological toxicities after inhalation exposures to HDl could be identified in laboratory animals. In an acute-duration study, groups of 4 male albino ChR-CD rats were exposed to various concentrations of HDl for 4 or 8 hours. When rats were exposed to 370 ppm from a bubbler of HDl warmed to 40-50 °C, they died after 2-3 hours of exposure, with irritation and convulsions observed prior to death. However, mechanical difficulties with the exposure apparatus may have contributed other factors that might have been responsible for the convulsions and eventual death of these animals (Haskell Laboratory 1961). 

This strong mineral is a severe eye, skin, and mucous membrane irritant, and is highly toxic if inhaled. Inhalation of vapors may cause severe irritation of the respiratory system, coughing, and difficulty breathing. Its systemic effects are unknown. 

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