Cornea, injury

Toxicoiogy Causes eye irritation, cornea injury may cause respiratory tract irritation, si. skin Irritation prolonged overexposure may cause difficulty breathing ing. may cause abdominal discomfort, nausea, diarrhea TSCA listed Environmentai Biodeg. 

Properties Wh. waxy solid mild odor sol. > 10% in water sp.gr. 1.001-1.004 (65.5/ 25 C) vise. 75 cSt (37.8 C) m.p. 34 C flash pt. (PMCC) 221 C pH 5.5-8 Toxicology Causes eye irritation, cornea injury may cause respiratory tract irritation, skin irritation inh. may cause nose/throat discomfort, nasal discharge, coughing ing, may cause abdominal discomfort, nausea, diarrhea may contain < 100 ppm EO TSCA listed... 

Acrolein vapor is highly irritating to the eyes, causing pain or discomfort in the eye, profuse lacrimation, involuntary blinking, and marked reddening of the conjunctiva. Splashes of Hquid acrolein will produce a severe injury to the eyeHds and conjunctiva and chemical bums of the cornea. 

In humans, cases of dermatitis have been described after contact with DHBs. Combined exposure to hydroquinone and quinone airborne concentrations causes eye irritation, sensitivity to light, injury of the corneal epithelium, and visual disturbances (126). Cases with an appreciable loss of vision have occurred (127). Long-term exposure causes staining due to irritation or allergy of the conjunctiva and cornea and also opacities. Resorcinol and catechol are also irritants for eyes. 

These drugp possess anti-inflammatory activity and are used for inflammatory conditions, such as allergic conjunctivitis, keratitis, herpes zoster keratitis, and inflammation of the iris. Corticosteroids also may be used after injury to the cornea or after corneal transplants to prevent rejection. 

Cornea Replacement for corneal opacity due to congenital diseases, injury, etc. 

Injury (either physical or chemical) to the comeal endothelial cells has a marked efiect on occular function as these cells are responsible for maintaining the thickness and clarity of the cornea, yet they cannot be replaced if damaged. Immunohistochemical studies have revealed that enzymatic antioxidant defences, SOD, CAT and GSHPx, are similarly distributed in the corneal epithelium and endothelium (Rao etal., 1985 Attala et d., 1987, 1988). Other antioxidants include ascorbate, carotenoids and vitamin E (Fleath, 1962). 

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). ... 

Calcium hydroxide is one of the most common causes of severe chemical eye burns. In almost all cases there is a semisolid particulate paste in contact with the cornea and conjunctiva, tending to adhere and to dissolve slowly. Strongly alkaline calcium hydroxide solution is formed and causes severe injury if not removed promptly. 

The liquid is only slightly irritating to the skin, but dropped into the eye it causes moderate injury to the cornea. ... 

Application of the liquid to animal skin caused moderate irritation. Chronic topical administration of a 5% solution to mice did not cause skin tumors or any visible skin reaction. In the eyes, glycidol produced severe irritation despite the severity of primary injury, no blindness or permanent defects in the cornea, lens, or iris resulted from the applications. 

When methyl 2-cyanoacrylate was applied as an adhesive to rabbit or human eyes, some reports described corneal haze and inflammation other reports with highly purified material indicated less toxicity. Mistaken use in the eyes as eyedrops has caused immediate brief smarting and firm gluing of the eyelids together. Acetone on a swab can be used to unglue the lids and remove the glue from the cornea with minimal, if any, injury to the corneal epithelium. ... 

The vapor causes eye irritation at 15 ppm eye contact with the solid may result in conjunctivitis, superficial injury to the cornea, chorioretinitis, scotoma, and diminished visual... 

A solution of rhodium trichloride in the eye of a rabbit gave a delayed injurious reaction 0.1 mg of solution adjusted to pH 7.2 with ammonium hydroxide was placed for 10 minutes in a rabbit eye after the corneal epithelium had been removed an orange coloration of the cornea occurred that faded to faint yellow within 8 weeks. During the first 2-3 weeks, the cornea was slightly hazy in the third week, white opacities gradually developed and, finally, there was extensive opacification and vascularization. 

Repeated application of 95% xylene to rabbit skin caused erythema and slight necrosis. Instilled in rabbit eyes, it produced conjunctival irritation and temporary corneal injury. Exposure to the vapors produced reversible vacuoles in the corneas of cats. 

Application of a 0.1M solution of yttrium chloride to the eyes of rabbits caused no injury similar exposure of eyes from which the corneal epithelium had been removed resulted in immediate slight haziness of the cornea, which subsequently became opaque and vascularized. The 2003 ACGIH threshold limit value-time-weighted average (TLV-TWA) for yttrium and compounds is 1 mg/m as Y. 

The acute pathologic effects of H on the eye include edematous clouding of the cornea and necrosis of corneal stroma. About 5 h later, infiltration by segmented leukocytes is noted at the sclero-comeal junction and in the corneal stroma. Healing usually occurs in several weeks, but the Injury may result in persistent or recurrent corneal ulceration and blindness. 

Acute injuries of the eyes, primarily from effects of blast and missiles, may occur from tear-gas weapons, such as pen guns. The lnmeulate effects of these Injuries include swelling and edema of the lids, with penetration of skin, conjunctiva, cornea, sclera, or globe by gunpowder and CN conjunctival ischemia and chemosls corneal edema, erosion, Inflammation, or ulceration and focal hemorrhage. 13,20... 

HDI has been demonstrated to be an ocular irritant in laboratory animals in several studies. HDI (0.1 mL, undiluted) was instilled into both eyes of a male albino rabbit. One eye was washed 20 seconds later with large amounts of water, whereas the other eye was not washed. The animal was sacrificed 8 days after treatment. Initially, the exposure caused severe conjunctival inflammation accompanied by serous and hemorrhagic exudates of both eyes, with severe (unwashed eye) or moderate (washed eye) corneal injury. When the rabbit was sacrificed 8 days after treatment, the corneas of both eyes appeared dull and the eyelids were inflamed and still showed the hemorrhagic and serous exudates. Healed eomeal lesions... 

Burns, F.R., Paterson, C.A. Chemical injuries Mechanisms of corneal damage and repair. In Beuerman, R.W., Crosson, C.E., Kaufman, H.E. (eds.) Healing Processes in the Cornea. Advances in Applied Biotechnology Series, vol. 1, pp. 45-58. Gulf, Houston (1989)... 

Ucakhan, 0.0., Koklu, G., Firat, E. Nonpreserved human amniotic membrane transplantation in acute and chronic chemical eye injuries. Cornea 21, 169-172 (2002)... 

Fogla, R., Padmanabhan, R Deep anterior lamellar keratoplasty combined with autologous limbal stem cell transplantation in unilateral severe chemical injury. Cornea 24, 421-425 (2005)... 

Application of 1,4-benzoquinone causes local skin changes including discoloration, erythema and the appearance of papules necrosis can occur. Exposure to vapours induces serious vision disturbances injury extends through the entire conjunctiva and cornea (lARC, 1977). 

---