In toxicity

The alcohols are toxic orally, through skin absorption, and through inhalation. The secondary alcohols are more toxic than the tertiary. The glycols are relatively low in toxicity. 

The bicychc phosphite intermediate is highly neurotoxic, but, after the ring-opening step, the product is low in toxicity. Antiblaze 19 and 1045 are... 

In general, the PCTFE resins have been found to be low in toxicity and irritation potential under normal handling conditions. Specific toxicological information and safe handling procedures are provided by the manufacturer of specified PCTFE products upon request. 

Monoethan olamine and monoisopropan olamine may be moderately toxic by absorption through the skin. The other amines are low in toxicity by this route and are not likely to be absorbed in acutely toxic amounts. In the event of skin contact, clothing and shoes should be removed promptly, and the skin thoroughly washed with water. Contaminated clothing should be thoroughly cleaned before reuse shoes and leather products should be discarded. 

When sulfonic acids are neutralized to sulfonic acid salts, the materials become relatively innocuous and low in toxicity, as compared to the parent sulfonic acid (see Table 4). The neutralized materials cause considerably less eye and skin irritation. The most toxic route of entry for sulfonic acid salts is ingestion (39). The toxicity of neutralized sulfonic acids, especially detergent sulfonates, has been directiy related to the foaming capabiUty of the material. 

Antagonism is appHed to a situation where two chemicals, given together, interfere with each other s action or where one interferes with the action of the other. The result will usually be a decrease in toxic injury. A special case of antagonism is in studies on antidotal action. 

Fig. 3. Schematic representation showing the anatomical basis for differences in the quantitative supply of absorbed material to the Hver. By swallowing (oral route), the main fraction of the absorbed dose is transported direcdy to the Hver. FoUowing inhalation or dermal exposure, the material passes to the pulmonary circulation and thence to the systemic circulation, from which only a portion passes to the Hver. This discrepancy in the amount of absorbed material passing to the Hver may account for differences in toxicity of a material by inhalation and skin contact, compared with its toxicity by swallowing, if metaboHsm of the material in the Hver is significant in its detoxification or metaboHc activation.

In addition to the effect of biological variabihty in group response for a given exposure dose, the magnitude of the dose for any given individual also determines the severity of the toxic injury. In general, the considerations for dose—response relationship with respect to both the proportion of a population responding and the severity of the response are similar for local and systemic effects. However, if metabohc activation is a factor in toxicity, then a saturation level may be reached. 

The metabohtes of vitamin D are usually more toxic than the vitamin because the feedback mechanisms that regulate vitamin D concentrations are circumvented. 25-Hydroxycholecalciferol has a one-hundredfold increase in toxicity over vitamin D when fed to chicks (220) and 1 a,25-dihydroxy vitamin D is several times more toxic than the 25-hydroxy analogue. Vitamin D2 seems to have less toxicity than vitamin D, a circumstance which is beheved to be caused by the more efficient elimination of 25-hydroxy and the 1 a,25-dihydroxy vitamin D2 from the animals. Estimated safe upper dietary levels are given in Table 11. 

Although biphenyl and the terphenyls fall under the ha2ardous chemical criteria of the OSHA Ha2ard Communications Standard, the products themselves are fairly low in toxicity and do not constitute a serious industrial ha2ard. Some relevant exposure and toxicity data are summari2ed in Tables 5 and 6. 

Safety. Hydrogenated terphenyls are low in toxicity as the following data (78) indicate. Single exposure (acute) studies show ... 

Bismuth subsahcylate [14882-18-9] Pepto-Bismol, is a basic salt of varying composition, corresponding approximately to i9-H0CgH4C02(Bi0). Like a number of other insoluble bismuth preparations, it is not currentiy approved in the United States for the treatment of peptic ulcer disease but is under active investigation for this purpose (180). It does appear to be effective for the rehef of mild diarrhea and for the prevention of travelers diarrhea (181). The ready availabiUty of this dmg, however, may lead to its ovemse and result in toxic effects caused by both the saUcylate and bismuth components. It has been suggested that bismuth subsahcylate is somewhat effective in the symptomatic treatment of isosporiasis, a disease caused by the intracellular parasite Isospora belli (182). 

In general the lanthanides, including cerium, have a low toxicity rating (17), especially when they are present in material having low aqueous solubiUty. When orally adrninistered poor absorption from the gastrointestinal tract tends to result in the lanthanides generally having Httle effect. The anion is often an important deterrninant in toxicity. 

It is established by biotesting that complexation and adsor ption ar e the most important processes promoting transformation of metal compounds in biologically and the chemically inactive forms and essential decrease their toxicity. The kinetics data have shown the maximal decrease in toxicity was observed in natural water where the complexation occurred with participation of both DOM and added HS. 

M. H. Depledge, in Toxic Impacts of Wastes on the Aquatic Environment, ed. J. F. Tapp, S. M. Flunt... 

S. -Z. Yu, in Toxic Cyanobacteria Current Status of Research and Management, proeeedings of an... 

T. Kuiper-Goodman, S. Gupta, H. Combley and B. H. Thomas, in Toxic Cyanobacteria Current... 

I ositive seals have been used in flammable and some toxic services In toxic applications, an isolating seal must be included in the seal contigu-... 

Exposures to chemicals, resulting in toxic effects or oxygen-deficient atmospheres, may arise in a variety of industrial situations. A summary of common sources is given in Table 5.18 clearly this is not exhaustive since exposure may result whenever materials are mixed, machined, heated, dispersed or otherwise processed or used. 

Acrylonitrile (Vinyl cyanide) CH,CHCN Closely resembles HCN in toxic action Poisonous by inhalation, ingestion or skin absorption Emits cyanides when heated or contacted by acids or acid fumes Symptoms flushed face, irritation of eyes and nose, nausea etc. Colourless flammable liquid with mild, faintly pungent odour Elash point 0°C. Dilute water solutions also have low flash points... 

The variation in toxicity of common organophosphate insecticides is exemplified in Table 5.37. The range of chlorinated hydrocarbon insecticides (Table 5.38) have, with the exception of Endrin and Isodrin, somewhat lower oral and dermal toxicities. The toxicities of a range of oilier insecticides, fungicides, herbicides and rodenticides are summarized in Table 5.39. 

PR valves in toxic vapor services where discharge to the atmosphere would result in the calculated concentration at the property line or at any working area (either at grade or an elevated platform) exceeding the Threshold Limit Value (TLV). 

It is important to note that in some installations where local pollution regulations would not permit venting a condensible blowdown tank in toxic service to the atmosphere, a pressure drum or sphere, vented to a flare, may be necessary. 

Diamond, G. L. et al., 1988, A Portable Computing System for Use in Toxic Gas Emergencies, Ontario Ministry of the Environment, ARB-150-87, ISBN 0-7729-3448-7, revised. 

Kaufman, J. W. (1999). The role of upper airway heat and water vapor exchange in hygroscopic aerosol deposition iii the human airway. In Toxicity Assessment Alternatives Methods, Issues, Opportunities (H. Salem and S.A. Katz, Eds.), pp. 63-70. Humana Press Inc., Totow a, NJ. 

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