Irritant solvents

A volume of 0.1 ml of the drug in a non-irritating solvent is inoculated into the conjunctival sack of each on rabbit out of six rabbits or directly on the cornea. The eye lid is kept close by using two fingers for some seconds to assure close contact with the cornea. Effects oc-... 

Clean air is also ranked in Figure 4 at an average eye response of 300 sec. Six solvents are as irritating or less irritating than clean air. Eye response is very subjective, and in my opinion response times over 200 sec indicate a low irritation factor. Because of this subjectivity, these six solvents might be considered non-eye-irritating solvents. 

Paint and varnish removers are especially noxious to the skin because they may contain, in addition to irritating solvents, many caustic chemicals, such as sodium phosphate, sodium silicate and caustic soda, as well as special chemicals such as dibutylthiourea. Solvents include, e.g., methylene chloride, methyl alcohol, ethyl alcohol and toluene (Kanerva et al. 1984 Fischer and Adams 1990 Vincent et al. 1994). 

ICD is common among rubber workers, in whom it is usually caused by irritant solvents and cleansers... 

Solvent-repellent cream protects against irritating solvents and oils. 

Full eye protection should be worn whenever handling acryhc monomers contact lenses must never be worn. Prolonged exposure to Hquid or vapor can result in permanent eye damage or blindness. Excessive exposure to vapors causes nose and throat irritation, headaches, nausea, vomiting, and dizziness or drowsiness (solvent narcosis). Overexposure may cause central nervous system depression. Both proper respiratory protection and good ventilation are necessary wherever the possibiHty of high vapor concentration arises. 

Toxicology. The nitroparaffins have minimal effects by way of actual contact. There were neither systemic effects nor irritation in dermal studies in rabbits. Human exposure of a prolonged or often-repeated nature has led to low grade irritation attributable to removal of oil from the skin, an effect produced by most organic solvents. Eye irritation potential of all four nitroparaffins has been deterrnined in rabbits. Other than a transient slight redness and some lachrymation, no effects were noted. The average Draize score was 0.0. The acute oral toxicity, LD q, of all four nitroparaffins has been deterrnined in the rat (Table 8). 

Extreme caution must be taken to prevent the possibility of fire when using flammable removers. Extra care must be taken when stripping on location to secure the area of ignition sources. When used on lacquer finishes, the dissolved finish and remover combined are extremely flammable. Natural mbber, neoprene, or other gloves suitable for use with the remover formula must be worn. The effect of skin contact with the remover is limited because there is immediate irritation and discomfort. Canister respirators are available for most petroleum and oxygenate remover solvents. Symptoms of long-term overexposure should be compared to symptoms of the major ingredients in the formula. 

Mineral oil and paraffins should not be used, because these are not metabolized and may irritate tissue. Various other additives are needed for stabiUty, stefihty, and isotonicity antimicrobial preservatives, antioxidants (qv), chelating agents (qv), and buffers. No parenteral container material is completely inert to parenteral solvent systems. 

Health and Safety Factors. Animal-feeding studies of DMPPO itself have shown it to be nontoxic on ingestion. The solvents, catalyst, and monomers that are used to prepare the polymers, however, should be handled with caution. Eor example, for the preparation of DMPPO, the amines used as part of the catalyst are flammable toxic on ingestion, absorption, and inhalation and are also severe skin and respiratory irritants (see Amines). Toluene, a solvent for DMPPO, is not a highly toxic material in inhalation testing the TLV (71) is set at 375 mg/m, and the lowest toxic concentration is reported to be 100—200 ppm (72). Toxicity of 2,6-dimethylphenol is typical of alkylphenols (qv), eg, for mice, the acute dermal toxicity is LD q, 4000 mg/kg, whereas the acute oral toxicity is LD q, 980 mg/kg (73). The Noryl blends of DMPPO and polystyrene have PDA approval for reuse food apphcations. 

Health and Safety Factors. l-Meth5l-2-pyrrobdinone is less toxic than many other dipolar aprotic solvents. The LD q for white rats is 4.2 mL/kg. Although it does not appear to be a sensitising agent, prolonged contact with skin should be avoided. It is a moderate eye irritant. 

Dichloroethane is one of the more toxic chlorinated solvents by inhalation (49). The highest nontoxic vapor concentrations in chronic exposure studies with various animals range from 100 to 200 ppm (50,51). 1,2-Dichloroethane exhibits a low single-dose oral toxicity in rats LD q is 680 mg/kg (49). Repeated skin contact should be avoided since the solvent can cause defatting of the skin, severe irritation, and moderate edema. Eye contact may have slight to severe effects. 

Entry into a tank that has contained any chlorinated or any easily evaporated solvent requires special procedures to ensure worker safety. The heavier vapors tend to concentrate in unventilated spaces. The proper tank entry procedure requires positive ventilation, testing for residue solvent vapor and oxygen levels, and the use of respiratory equipment and rescue harness. Monitoring the tank from outside is also important. The use of an appropriate gas mask is permissible in vapor concentrations of less than 2% and when there is no deficiency of atmospheric oxygen, but not for exposures exceeding one-half hour. Skin exposure to 1,1,1-trichloroethane can cause irritation, pain, bHsters, and even burning. Eye exposure may produce irritation, but should... 

Benzyl chloride [(chloromethyl)henzene, a-chlorotoluene], CgH CH2Cl, is a colorless Hquid with a very pungent odor. Its vapors are irritating to the eyes and mucous membranes, and it is classified as a powerfljl lacrimator. The physical properties of pure benzyl chloride are given in Table 2 (2—7). Benzyl chloride is insoluble in cold water, but decomposes slowly in hot water to benzyl alcohol. It is miscible in all proportions at room temperature with most organic solvents. The flash point of benzyl chloride is 67°C (closed cup) 74°C (open cup) autoignition temperature is 585°C lower flammability limit 1.1% by volume in air. Its volume coefficient of expansion is 9.72 x. ... 

Alcohols Used as a solvent in coatings Surface coatings, printing Sensory and respiratory irritation... 

Chlorophenyl isothiocyanate [2131-55-7] M 169.6, m 44 , 43-45 , 45 , 46 , 47 , b 110-115 /4mm, 135-136 /24mm. Check the IR first. Triturate with pet ether (b 30-60°) and decant the solvent. Repeat 5 times. The combined extracts are evap under reduced press to give almost pure compound as a readily crystallisable oil with a pleasant anise odour. It can be recrystd from the minimum vol of EtOH at 50° (do not boil too long in case it reacts). It can be purified by vac distn. IRRITANT. [Org Synth Coll Vol V 223 7 975.1... 

Diethyl pyrocarbonate (DEP) [1609-47-8] M 162.1, b 38-40°/12mm, 160-163 /atm, d 1.119, Op 1.398. Dissolve in Et20, wash with dilute HCl, H2O, dry over Na2S04. filter, evaporate and distil the residue first in vacuo then at atmospheric pressure. It is soluble in alcohols, esters, ketones and hydrocarbon solvents. A 50% w/w soln is usually prepared for general use. Treat with great CAUTION as DEP irritates the eyes, mucous membranes and skin. [Boehm and Mehta Chem Ber 71 1797 1938 Thoma and Rinke Justus Liebigs Ann Chem 624 30 1959.]... 

Nitrobenzyl bromide [100-11-8] M 216.0, m 98.5-99.0 . Recrystd four times from abs EtOH, then twice from cyclohexane/hexane/ benzene (1 1 1), followed by vac sublimation at 0.1mm and a final recrystn from the same solvent mixture. [Lichtin and Rao J Am Chem Soc 83 2417 1961.] Has also been crystd from pet ether (b 80-100°, lOmL/g, charcoal). It slowly decomposes even when stored in a desiccator in the dark. IRRITANT. 

Modified liquid epoxy resins liquid epoxy resins with added reactive diluents or solvents mild to moderate irritants moderate to strong sensitizers low volatility, exposure unlikely unless heated, sprayed, or spread over large unventilated surfaces low toxicity... 

Solvents acetone, methyl ethyl ketone (MEK), toluene, xylene, glycol, ethers, alcohol defats and dries skin some may be absorbed may carry other components through skin high volatility, exposure possible irritation central nervous system depression (e.g. dizziness, loss of coordination) low to high toxicity, longterm effects... 

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