Alkaline irritation

Toxicoiogy LD50 (rat) 1000-3000 mg/kg alkaline irritant, desiccant to eyes desiccant to skin on prolonged contact with cone, form mild purgative when ingested Environmentai Readily biodeg. LC50 (fish) 3-20 mg/l, (daphnia, 24 h) 10-50 mg/l ... 

Potassium biduoride crystals may break down to a fine white powder that is readily airborne. In this form, the salt is quite irritating to the nasal passages, eyes, and skin. Therefore, the hands and eyes should be protected and acid dust masks should be worn while handling, as an acid duoride KHF2 can cause superficial hydroduoric acid-type bums. Areas of skin that have been in contact with potassium biduoride should be washed as soon as possible with mildly alkaline soaps or borax-containing hand cleaners. If there has been contact with the eyes, they should be washed well with water and a physician should be consulted. 

Health and Safety. The dermal toxicology of alkaline solutions of thioglycolic acid has been reviewed extensively (63—65). The reagent has been found harmless to normal skin when used under conditions adopted for cold waving. Some irritation is observed on abraded skin but this appears to be associated with the alkaline component of the waving solution (65). Hand protection is recommended for the professional hairdressers who routinely handle these products. 

The eyes are particularly susceptible to Hquids, gases, and some soHds. The conjunctival membrane surrounding the eye is easily irritated. Alkaline materials, eg, hydroxides and amines, destroy the eye tissues rapidly, frequently causiug partial or complete loss of vision. 

Skin Irritation. Monoethan olamine and monoisopropan olamine, being strongly alkaline, are skin irritants, capable of producing serious injury in concentrations of 10% or higher upon repeated or prolonged contact. Occasional short contact, assurning the material is thoroughly washed off, should have httle adverse effect. 

Undiluted DMAMP, AMP-95, and AB cause eye bums and permanent damage, if not washed out immediately. They are also severely irritating to the skin, causing bums by prolonged or repeated contact. Of these three aLkanolarnines, only AMP has been studied in subchronic and chronic oral studies. The principal effect noted was the action of AMP on the stomach as a result of its alkalinity. The no-observed-effect level (NOEL) in a one-year feeding study in dogs was 110 ppm in the diet. In general, the low volatility and appHcations for which these products are used preclude the likelihood of exposure by inhalation. 

Sodium metaborate hydrates are more alkaline than borax and greater care is required in handling. The metaborate material is harm fill to the eyes and can cause skin irritation. Gloves, goggles, and a simple dust mask should be used when handling sodium metaborate powder. 

Ammonium hydroxide (NH4OH) (aqueous ammonia solution) Weakly alkaline. Emits ammonia gas. Severe eye irritant... 

Acetone cyanohydrin (Oxyisobutyric nitrile) (CH3)2C(0H)CN Highly toxic by inhalation or ingestion Irritating and moderately toxic upon skin contact Readily decomposes to HCN and acetone at 1 20°C, or at lower temperatures when exposed to alkaline conditions Colourless combustible liquid Elash point 73°C Ignition temperature 68.7°C Completely soluble in water... 

It is important to stress that neither sodium silicate nor silico fluoride will improve the performance of a poor, low-strength, dusty concrete floor and if the surface is too porous, there is no way that all the material applied can react with the relatively small quantity of free lime in the concrete surface. All that will happen is that the pores will be filled with non-reacted powder, producing a most unpleasant alkaline dust, which can be very irritating to the skin and eyes when the floor is put into service. 

TSPP is slightly alkaline and has a bitter taste, requiring additional flavorings to mask it. Also, additional detergents must be added to keep it in solution. All of these factors can irritate oral membranes and cause sensitivity. 

Sodium hydroxide (NaOH) (caustic soda) Potassium hydroxide (KOH) (caustic potash) Calcium hydroxide (Ca(OH)2) (slaked lime) Ammonium hydroxide (NH4OH) (aqueous ammonia solution) White deliquescent solid. Sticks, flakes, pellets. Dissolution in water is highly exothermic. Strongly basic. Severe hazard to skin tissue White deliquescent solid. Sticks, flakes, pellets. Dissolution In water is highly exothermic. Strongly basic. Severe hazard to skin tissue White powder soluble in water yielding lime water. Alkaline Weakly alkaline. Emits ammonia gas. Severe eye irritant... 

Watts (1979), while agreeing that bacterial contamination plays an important role in causing irritation to tissues, showed that a silicate cement even under germ-free conditions produced tissue damage. Of course, the acidic dental silicate cement does not possess the antiseptic action of the alkaline cements. 

Secretion of the large intestine. The large intestine produces an alkaline mucus secretion, the function of which is to protect the mucosa from mechanical or chemical injury. Mucus provides lubrication to facilitate the movement of the contents of the lumen. Bicarbonate ion neutralizes the irritating acids produced by local bacterial fermentation colonic secretion increases in... 

Hepatic Effects. Liver function tests (serum bilirubin, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transferase) completed in 11 hexachloroethane workers were within the normal range (Selden et al. 1994). Plasma hexachloroethane levels in these workers, who wore protective equipment, were 7.3 + 6.04 pg/L at the time of the tests (Selden et al. 1993). Mild skin and mucous membrane irritation were reported in the exposed group, suggesting that exposure may have been through either the inhalation or dermal routes of exposure. 

Liquid anhydrous ammonia in contact with the eyes may cause serious injury to the cornea and deeper structures and sometimes blindness on the skin it causes first- and second-degree burns that are often severe and, if extensive, may be fatal. Vapor concentrations of 10,000 ppm are mildly irritating to the moist skin, whereas 3 0,000 ppm or greater causes a stinging sensation and may produce skin burns and vesiculation. With skin and mucous membrane contact, burns are of three types cryogenic (from the liquid ammonia), thermal (from the exothermic dissociation of ammonium hydroxide), and chemical (alkaline). ... 

Barium hydroxide and barium oxide are strongly alkaline in aqueous solution, causing severe burns of the eye and irritation of the skin. ... 

The irritant effects are probably due primarily to its alkalinity, but dehydrating and thermal effects also may be contributing factors. Strong nasal irritation was observed from exposure to a mixture of dusts containing calcium oxide in the range of 25mg/m but levels of 9-lOmg/m produced no observable irritation. Inflammation of the respiratory tract, ulceration and perforation of the nasal septum, and pneumonia have been attributed to inhalation of calcium oxide dust severe irritation of the upper respiratory tract ordinarily causes persons to avoid serious inhalation exposure. ... 

Cyanide solutions or cyanide aerosols generated in humid atmospheres have been reported to cause irritation of the upper respiratory tract (primarily nasal irritation) and skin. Skin contact with solutions of cyanide salts can cause itching, discoloration, or corrosion, most likely due to the alkalinity of the solutions. Skin irritation and mild systemic symptoms (e.g., headache, dizziness) have been caused by solutions as dilute as 0.5% potassium cyanide. ... 

The liquid applied to the skin of rabbits under semiocclusion for 24 hours on 10 consecutive days caused only minor irritation. With long contact time, DEA is irritating to rabbit eyes at concentrations of 50% and above. Ttxicity resulting from direct contact may be in part due to irritation associated with the alkalinity of this chemical. ... 

In guinea pigs, 5% diisopropylamine caused dermal irritation with repeated exposures, but it was not a sensitizer. The irritative properties of diisopropylamine have been attributed to its alkaline pH, which is neutralized in some formulations. 

Ballantyne B, Myers RC, Blaszcak DL Influence of alkalinization of glutaraldehyde biocidal solutions on acute toxicity, primary irritancy, and skin sensitization. Vet Hum Toxicol 39(6) 340-346, 1997... 

No systemic effects have been reported from industrial exposure. Some inorganic tin compounds can cause skin or eye irritation because of acid or alkaline reaction produced with water. Tin tetrachloride, stannous chloride, and stannous sulfate are strong acids sodium and potassium stannate are strong... 

---