Effects on the Eyes

The effects of SM on human eyes were extensively described in casualties from WWI. Although the original reports of these casualties have not been located, they are described in the seientific literature of the time. Warthin  

A large number of injuries occurred in the production of SM between the World Wars. A summary of all injuries in the UK showed that 10.4% of the 939 eye casualties showed improvement of corneal injuries with time and only 1% had severe corneal lesions similar casualty rates for liquid and vapour exposure have been reported from the USA. Unfortunately, there were no long term follow-up studies of these patients to determine their ocular status years after exposure. 

The British reported many thousands of eye casualties during WWI and SM was responsible for 77% of these. Analysis of the total figures reveals that 75% of cases were relatively mild, amounting to conjunctival irritation requiring an average stay in hospital of 2 weeks. Another 15% were described as moderate, with incapacitation for 4-6 weeks. Finally, 10% were described as severe requiring periods of up to 6 months in hospital for symptoms to stabilise. A total of 51 British soldiers were reported as blinded and there were 180 vision related pensions.  

Acute severe injury of the eye with SM might result in recurrent corneal ulcerative disease for the remainder of the patient s life, with a maximum incidence occurring 15-20 years after the initial injury. Based on extensive data, there is a causal relationship between severe exposure to SM and the development of delayed recurrent keratitis. 

1 Immediate damage to the corneal epithelium with oedematous clouding and necrosis of the stroma  

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Ammonia is a strong local irritant which also has a corrosive effect on the eyes and the membranes of the pulmonary system. Vapor concentrations of 10,000 ppm are mildly irritating to the skin, whereas 30,000 ppm may cause bums. The physiological effects from inhalation are described in Table 16. Prolonged, intentional exposure to high levels of ammonia is unlikely because its characteristic odor can be detected at levels as low as 1 —5 ppm (94). The real danger occurs when escape is impossible, or the exposure victim has lost consciousness. 

Hydroxychloroquine administration may result in irritability, nervousness, anorexia, nausea, vomiting, and diarrhea This drug also may have adverse effects on the eye, including blurred vision, comeal edema, halos around lights, and retinal damage. Hematologic effects, such as aplastic anemia and leukopenia, may also be seen. 

The effect on the eyes was more noticeable. A single application of the solution mentioned above produced moderate redness and short and minor swelling of conjunctiva. Radiotracer studies with Hostapur SAS [102] revealed that after oral (up to 50 mg/kg) and dermal application on rats, the product and its metabolites were very quickly excreted either in completely oxidized form as carbon dioxide or in the urine and feces. Residues in organs and tissues after 7 days were well below 1 ppm. 

There were no treatment-related effects on retinal function and no morphological effects on the eyes of dogs that were exposed to 0.03, 0.30, or 3.00 mg/kg/day methyl parathion for 13 weeks and allowed 4 weeks of no exposure to recover (Daly 1989). 

HN-3 is similar to HN-1 and HN-2, in that it is a cumulative poison that is highly irritating to the eyes and throat. Permanent corneal damage can occur from vapor exposure alone at concentrations around 200 mg/min/m3. HN-3 does not create sufficient vapor density to cause rash and blistering from a single exposure. Blistering may result from contact with the liquid form, multiple or persistent vapor exposure, or vapor condensation in sweat. A rash will develop from contact with liquid within approximately 1 hour, followed by blistering 6 to 12 hours later. Toxic effects on the eyes are immediate. 

We do not know how mirex directly affects the health of people. However, animal studies have shown that eating mirex can cause harmful effects on the stomach, intestines, liver, and kidneys. Eating mirex can also cause harmful effects on the eyes, thyroid, nervous system, and reproductive system. Since these effects occur in animals, they may also occur in people. 

Effect on the eye. Leopold and Comroe4 recorded the actions of D.F.P. on the normal eye, expanding the earlier British work (pp. 2, 43). They confirmed the prolonged myosis lasting up to 3 weeks with a spasm of the ciliary muscle for 3-7 days. There is usually a decrease in the intra-ocular tension, although occasionally there may be a slight rise before a fall in pressure. The action outlasts that of common myotics, and a 0-1 per... 

Ocular Effects. No studies were located regarding ocular effects in humans after exposure to 3,3 -dichlorobenzidine by any route. No adverse effects on the eye were noted when dichlorobenzidine (isomer unspecified, free base) was directly placed in the conjunctival sac of the eye of rabbits (Gerarde and Gerarde 1974). However, 0.1 mL 3,3 -dichlorobenzidine dihydrochloride (dihydro salt of 3,3 -dichloro-benzidine) in a 20% com oil suspension produced erythema, pus, and comeal opacity, giving a 76% score in the Draize test within an hour when placed in the conjunctival sac of the eye of the rabbit (Gerarde and Gerarde 1974). Apparently, the irritant effects of hydrochloric acid Ifom the salt-compoimd contributed... 

In humans, inhalation of the gas at fractions of a part per million produced intractable headache. Although there are no reports of effects on the eyes or skin of humans, it would be expected that the gas under pressure impinging upon the eyes or skin would produce serious burns. ... 

In workers engaged in the manufacture of aryl phosphates (including up to 20% TOCP) and exposed to concentrations of aryl phosphates at 0.2-3.4mg/m , there was some inhibition of plasma cholinesterase but no correlation of this effect with degree of exposure or with minor gastrointestinal or neuromuscular symptoms. No effects on the eyes or skin have been reported TOCP is readily absorbed through the skin without local irritant effects. 

Ephedrine increases systolic and diastolic blood pressure heart rate is generally not increased. Contractile force of the heart and cardiac output are both increased. Ephedrine produces bronchial smooth muscle relaxation of prolonged duration when administered orally. Aside from pupillary dilation, ephedrine has little effect on the eye. 

From the outset, their hypothesis caused worldwide concern because UV-B can damage DNA, cause skin cancer, including malignant melanoma in humans, and have long-term effects on the eye, in addition to its impact on a variety of ecosystems. 

On contact with moist membranes, S02 forms sulfurous acid, which is responsible for its severe irritant effects on the eyes, mucous membranes, and skin. Approximately 90% of inhaled S02 is absorbed in the upper respiratory tract, the site of its principal effect. The inhalation of S02 causes bronchial constriction parasympathetic reflexes and altered smooth muscle tone appear to be involved. Exposure to 5 ppm S02 for 10 minutes leads to increased resistance to airflow in most humans. Exposures of 5-10 ppm are reported to cause severe bronchospasm 10-20% of the healthy young adult population is estimated to be reactive to even lower concentrations. The phenomenon of adaptation to irritating concentrations has been reported in workers. However, current studies have not confirmed this phenomenon. Asthmatic individuals are especially sensitive to S02. 

Nasal budesonide or beclomethasone 100 micrograms bd for 3-9 months had no effect on the eyes in 26 patients who had undergone endoscopic sinus surgery (440). Ophthalmologic examination, tonometry, visual field testing, and biomicroscopic studies showed no evidence of ocular hypertension or posterior subcapsular cataract. 

A number of toxic effects on the blood have been documented, including agranulocytosis caused by chlorpromazine, hemolytic anemia caused by methyldopa, and megaloblastic anemia caused by methotrexate. Toxic effects on the eye have been noted and range from retinotoxicity caused by thioridazine to glaucoma caused by systemic corticosteroids. 

The tertiary members of these classes (Figure 8-2) are often used for their effects on the eye or the central nervous system. Many antihistaminic (see Chapter 16 Histamine, Serotonin, the Ergot Alkaloids), antipsychotic (see Chapter 29 Antipsychotic Agents Lithium), and antidepressant (see Chapter 30 Antidepressant Agents) drugs have similar structures and, predictably, significant antimuscarinic effects. 

The prostaglandins and thromboxanes have major effects on four types of smooth muscle airway, gastrointestinal, reproductive, and vascular. Other important targets include platelets and monocytes, kidneys, the central nervous system, autonomic presynaptic nerve terminals, sensory nerve endings, endocrine organs, adipose tissue, and the eye (the effects on the eye may involve smooth muscle). 

Chloroquine is a 4-aminoquinoline used in the treatment and prophylaxis of malaria and hepatic amebiasis, as well as rheumatoid arthritis. Adverse effects are generally less common and less severe. Frequent effects include headache, GI disturbances, and diarrhea. Large doses may cause blurred vision and difficulty focusing. A common adverse effect on the eye is retinopathy. Parenteral therapy with chloroquine can be hazardous, and rapid intravenous injections may result in cardiovascular toxicity. Acute overdose is extremely dangerous death may occur within a few hours. Chloroquine should be used cautiously in patients with liver and kidney impairment. Chloroquine may aggravate the condition of myasthenia... 

In the evaluation of a chemical s toxic characteristics, determination of the irritant/corrosive effects on the eyes of mammals is an important parameter. Data obtained from this test indicate hazards likely to arise from exposure of the eyes and associated mucous membranes to the toxic chemical under test. 

Ocular Effects. Effects on the eyes due to direct contact of the eyes with airborne mists, dusts, or aerosols or chromium compounds are described in Section 2.2.3.2. An extensive epidemiological survey was conducted of housewives who lived in an area of Tokyo, Japan, in which contamination from chromium slag at a construction site was discovered in 1973. The housewives included in the study were those who lived in the area from 1978 to 1988, and controls included housewives who lived in uncontaminated areas. Questionnaires, physical examinations, and clinical tests were conducted annually. Higher incidences of subjective complaints of eye irritation were reported by the exposed population than the control population in the early years of the survey, but in later years the difference between the two groups became progressively less (Greater Tokyo Bureau of Hygiene 1989). 

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