Irritant effect

The most important polyhydric alcohols are shown in Figure 1. Each is a white soHd, ranging from the crystalline pentaerythritols to the waxy trimethylol alkyls. The trihydric alcohols are very soluble in water, as is ditrimethylol-propane. Pentaerythritol is moderately soluble and dipentaerythritol and tripen taerythritol are less soluble. Table 1 Hsts the physical properties of these alcohols. Pentaerythritol and trimethyl olpropane have no known toxic or irritating effects (1,2). Finely powdered pentaerythritol, however, may form explosive dust clouds at concentrations above 30 g/m in air. The minimum ignition temperature is 450°C (3). 

Exposure to PTFE can arise from ingestion, skin contact, or inhalation. The polymer has no irritating effect to the skin, and test animals fed with the sintered polymer have not shown adverse reactions. Dust generated by grinding the resin also has no effect on test animals. Formation of toxic products is unlikely. Only the heated polymer is a source of a possible health hazard (120). 

A.lkyl Sulfosuccinate Half Asters. These detergents are prepared by reaction of maleic anhydride and a primary fatty alcohol, followed by sulfonation with sodium bisulfite. A typical member of this group is disodium lauryl sulfosucciaate [26838-05-1]. Although not known as effective foamers, these surfactants can boost foams and act as stabilizers when used ia combination with other anionic surfactants. In combination with alkyl sulfates, they are said to reduce the irritation effects of the latter (6). 

In any case, the OEL-STEL is not a separate, independent exposure limit rather, it supplements the OEL-TWA and is intended to be used in normal work situations, not for emergencies. However, the OEL-STEL needs to be complemented by other precautions for substances that may be lethal at very high concentrations and for substances whose toxic or irritant effects are pronounced upon exposure to high concentrations for very short periods. 

Note The dipping reagent is to be preferred because of the strongly irritating effects of formaldehyde on the respiratory tract. Detection limits of ca. 10—40 ng have been reported for alkaloids [4] and 50 ng — 1 pg for -blockers [2, 3]. 

Reizung,/. irritation, etc. (see reizen). Reiz-wirkung, /. irritating effect stimulating effect, -wurfel, m. Mil.) irritant capsule, rekapitulieren, v.t. recapitulate. 

Allyl chloride is a colorless liquid, insoluble in water but soluble in many organic solvents. It has a strong pungent odor and an irritating effect on the skin. As a chemical, allyl chloride is used to make allyl alcohol, glycerol, and epichlorohydrin. 

Preanesthetic drugs must be administered on time to produce their intended effects Failure to give the preanesthetic drug on time may result in events such as increased respiratory secretions caused by the irritating effect of anesthetic gasesand the need for an increased dose of the induction drug because the preanesthetic drug has not had time to sedate the patient. 

The emetic (a drug that induces vomiting) ipecac causes vomiting because of its local irritating effect on the stomach and by stimulation of the vomiting center in the medulla... 

In terms of local irritation effects, AOS are reported to result in marked irritation of the eyes at concentrations at or above 1.0%, with slight effects being observed at 0.1% [147,148,150]. Repeated application to rat skin over 15 days at concentrations of 20% or 30% did not result in any macroscopic changes. Microscopic examination, however, did show atrophy of the stratum... 

Hydroquinone is usually more effective when utilized in combination with other agents such as topical retinoids alone or topical retinoids and topical steroids (see Table 14.1). The addition of a weak topical steroid reduces the irritant effect of hydroquinone, but the treat-... 

Gaseous sulphur dioxide is highly irritant and practically irrespirable. Effects on the body are summarized in Table 4.3. It can be detected at about 3.5 ppm and the irritating effects would preclude anyone from suffering prolonged exposure at high concentrations unless unconscious, or trapped. 

Effect. Biomarkers of effects are not available for trichloroethylene. There is no clinical disease state that is unique to trichloroethylene exposure. Interpretation of the behavioral observations in humans is complicated by many factors, such as possible irritant effects of the odor and nonspecific effects on the nervous system (e.g., fatigue). Further studies in this area would be useful in determining the exposure levels that may be... 

Direct irritation of the mucosal lining by NSAIDs occurs because NSAIDs are weak acids. Topical irritation is therefore most pronounced with more acidic NSAIDs such as aspirin. While the direct irritant effects of NSAIDs play a contributory role in the development of NSAID-induced gastritis, this mechanism generally plays a minor role in the evolution of NSAID-induced PUD. 

Counterirritants are categorized by the Food and Drug Administration (FDA) into four groups (groups A-D) based on their primary actions (Table 57-2). They produce a feeling of warmth, cooling, or irritation that diverts sensation from the primary source of pain. Because these irritant effects are central to the beneficial actions, counterirritants should not be combined with topical anesthetics or topical analgesics. 

Recommend appropriate pharmacologic therapy and educate on proper use. If a counterirritant is recommended, counsel patients on the irritant effect of the product and recommend washing hands immediately after use and to avoid heating pads. For patients using a capsaicin product, emphasize that adherence to regular application is required for effectiveness. 

Rate of action Irritating effect on nose and throat is tolerable after 1 min at... 

Dermal Effects. Peeling of the facial skin was reported in one patient following probable exposure to 8-16 ppm of hydrogen sulfide, which was believed to be due to the irritant effect of the gas (Tvedt et al. 1991a, 1991b). ATSDR (1994) indicates that direct contact with liquefied hydrogen sulfide gas can cause frostbite. 

Only a few in vivo dermal toxicity studies have been reported so far. Huczko and Lange [50] evaluated the potential of raw CNTs to induce skin irritation by conducting two routine dermatological tests (patch test on 40 volunteers with allergy susceptibilities and Draize rabbit eye test on four albino rabbits). Koyama etal. [51] showed the biological responses to four different types of carbon nanotubes (SWNTs, two types of MWNTs with different diameters, and cup-stacked carbon nanotubes) after their subcutaneous implantation in mice. Both tests [50, 51] showed no or poor irritation effects. However, the in vitro studies in epidermal cell lines exposed to CNTs, and also a more recent report on the toxic outcomes of topical exposure of mice to SWNTs [46], have raised concerns over these assessments. Clearly, this is an area requiring further scientific evaluation. 

Workers exposed to acrylonitrile vapors at 16 to 100 ppm for 20 to 45 minutes complained of intolerable itching of the skin, but no dermatitis was observed (Wilson et al. 1948). This is presumably a direct irritant effect of acrylonitrile on the skin. 

The precise mechanism of monomethylhydrazine toxicity is uncertain. In addition to the contact irritant effects, the acute toxicity of dimethylhydrazine exposure probably involves the central nervous system as exemplified by tremors and convulsions (Shaffer and Wands 1973) and behavioral changes at sublethal doses (Streman et al. 1969). Additionally, renal and hepatic toxicity and hemolytic effects imply alternate mechanisms of toxicity. 

The precise mechanism of dimethylhydrazine toxicity is uncertain. In addition to the contact irritant effects, the acute effects of dimethylhydrazine exposure may involve the central nervous system as exemplified by tremors and convulsions (Shaffer and Wands 1973) and behavioral changes at sublethal doses (Streman et al. 1969). Back and Thomas (1963) noted that the deaths probably involve respiratory arrest and cardiovascular collapse. The central nervous system as a target is consistent with the delayed latency in response reported for dimethylhydrazine (Back and Thomas 1963). There is some evidence that 1,1-dimethylhydrazine may act as an inhibitor of glutamic acid decarboxylase, thereby adversely affecting the aminobutyric acid shunt, and could explain the latency of central-nervous-system effects (Back and Thomas 1963). Furthermore, vitamin B6 analogues that act as coenzymes in the aminobutyric acid shunt have been shown to be effective antagonists to 1,1-dimethylhydrazine toxicity (reviewed in Back and Thomas 1963). 

The largest number of studies of the toxicity of acrolein in animals was conducted by way of inhalation, probably because acrolein has an appreciable vapor pressure under ambient conditions and inhalation is the principal exposure for humans (Beauchamp et al. 1985). Because of their intolerance to sharp and offensive odor and to intense irritation of conjunctiva and upper respiratory tract, humans have not suffered serious intoxication from acrolein. The strong lacrimatory effect of acrolein is usually a warning to occupational workers. Physiological perception of acrolein by humans begins at about 500 to 1000 pg/L air with eye and nasal irritation. The irritating effects compel afflicted individuals to immediately leave the polluted area (Beauchamp etal. 1985). Laboratory animals died from inhalation of 8000 to 11,000 pg/L after 4 to 6 h, mice from 875,000 pg/L after 1 min, and rats from 660 pg/L for 24 days (Table 10.4). Animals dying from... 

Avoid foods that have a direct irritant effect on the esophageal mucosa (spicy foods, orange juice, tomato juice, and coffee). 

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