Cataract In Workers Research Articles

Cataract Formation by Near-infrared Radiation in Rabbits.

Surveys and epidemiological studies have shown an increased prevalence of cataracts in workers in the glass and steel industries. These cataracts are associated with exposure to intense infrared radiation (IR) emitted from heated materials and industrial furnaces. Thermal model calculations predicted that near and far IR would cause cataract with different mechanisms. The present study investigated cataract formation by near IR. Eyes of pigmented rabbits were exposed to IR at a wavelength of 808nm. Morphological changes in the anterior segment of the eye were assessed by slit-lamp microscopy, and temperature distributions in the anterior chamber of the eye were observed during IR exposure using microencapsulated thermochromic liquid crystals. Cortical cataract appeared below the exposed area of the iris in eyes that had been exposed for 6min to an irradiance of 1.27Wcm-2 or higher. The monitored temperature in the anterior chamber began to increase in the region adjacent to the exposed area of the iris with the onset of IR exposure. These results demonstrate that 808-nm IR is absorbed and converted to heat within the iris, which is then conducted to the lens and produce a cataract, as Goldmann theory states.

Not as Simple as It Looks

An epidemiological study was conducted in 55 subjects (mean age: 41) in hospitals to determine the prevalence of lens opacities and cataracts in workers exposed to ethylene oxide in six sterilisation units. The 21 exposed subjects over 45 were then compared with 16 non-exposed subjects, matched for age and sex. The relation between occupational exposure to ethylene oxide and white blood cell concentrations was also investigated. Lens opacities (independently of visual acuity) were observed in 19 of the 55 exposed. Among both exposed and non-exposed aged over 45, there were no significant differences with regard to the characteristics of lens opacities--prevalence (19 in the 21 exposed; 10 in the 16 non-exposed), distribution of the location, and importance and type (opalescence or discontinuous opacities). No link was found between the characteristics of the lens opacities and the characteristics of exposure: habitual exposure, measured between 0.06 and 39 ppm (cumulated in ppm-number of weekly hours-years) and accidental over-exposures (regular and irregular). For cataracts, defined by the association of lens opacities and a visual acuity less than 20/25 (this loss not being attributable to another cause), their prevalence differed significantly (p less than 0.05) between the exposed (six of 21) and the non-exposed (0 of 16); there was no relation between their existence and overexposures (the analysis for habitual exposure was not possible because of the small size of the sample). The risk of lens opacifications by ethylene oxide in cases of massive exposures as previously described could also exist during chronic exposure to low concentrations. It could be explained by saturation of protective mechanisms against alkylating action of this product. Linear relations were found between the logarithms of blood concentrations of polymorphoneutrophils (R=-0.54; p<0.005) and of lymphocytes (R=-0.45;p<0.05).

La cataracte radio-induite professionnelle chez cinq radiographes industriels

The industrial uses of ionizing radiation in Tunisia are expanding, especially in industry and most particularly in the nondestructive testing of welds. Thus workers operating in the non-destructive testing of welds may develop a radiation-induced cataract varying in time to onset depending on the dose. To describe the characteristics of the radiation-induced cataract in patients exposed to ionizing radiation, determine the risk factors of radiation-induced cataracts. This was an anamnestic, clinical, and environmental study of five cases of radiation-induced cataract in workers employed in non-destructive testing of welds. This series of five cases had a mean age of 30.2 years and 5.53 years of work experience, ranging from 14 months to 15 years. All the patients were male and industrial radiographers specialized in nondestructive testing of welds. The average duration of exposure to ionizing radiation was 5.53 years. None of the patients had worn protective gear such as eye goggles. The ophthalmic check-up for the five special industrial radiographers showed punctuate opacities in three cases, punctiform opacities in one eye in one case, and phacosclerosis with bilateral lens multiple crystalline stromal opacities in a case of micro-lens opacities in both eyes with opalescence of both eyes in one case. These cataracts had been declared as occupational diseases. The value of a specialized ophthalmologic surveillance among these workers and the early diagnosis of lens opacities must be emphasized.

Trinitrotoluene (TNT)‐induced cataract in Danish arms factory workers

To compare the prevalence of cataract in workers exposed to trinitrotoluene (TNT) to the prevalence in a group of unexposed workers, matched on age and sex, using Tiukina's description and grading of TNT-induced cataract. A total of 23 TNT-exposed and 44 unexposed workers underwent an eye examination performed by an ophthalmologist who did not know the exposure status of the subjects. All lens opacities matching Tiukina's description were classified as TNT cataract and graded on Tiukina's scale of stages 1-4. Four cases of TNT-induced cataract were identified among the 23 TNT-exposed workers and none in the unexposed group (p < 0.01). Exposure to TNT may cause a unique type of cataract, which a general ophthalmologist, using Tiukina's description and grading scale, will be able to distinguish from other cataracts.

Toxicity of ethylene oxide on the lens and on leukocytes: an epidemiological study in hospital sterilisation installations.

An epidemiological study was conducted in 55 subjects (mean age: 41) in hospitals to determine the prevalence of lens opacities and cataracts in workers exposed to ethylene oxide in six sterilisation units. The 21 exposed subjects over 45 were then compared with 16 non-exposed subjects, matched for age and sex. The relation between occupational exposure to ethylene oxide and white blood cell concentrations was also investigated. Lens opacities (independently of visual acuity) were observed in 19 of the 55 exposed. Among both exposed and non-exposed aged over 45, there were no significant differences with regard to the characteristics of lens opacities--prevalence (19 in the 21 exposed; 10 in the 16 non-exposed), distribution of the location, and importance and type (opalescence or discontinuous opacities). No link was found between the characteristics of the lens opacities and the characteristics of exposure: habitual exposure, measured between 0.06 and 39 ppm (cumulated in ppm-number of weekly hours-years) and accidental over-exposures (regular and irregular). For cataracts, defined by the association of lens opacities and a visual acuity less than 20/25 (this loss not being attributable to another cause), their prevalence differed significantly (p less than 0.05) between the exposed (six of 21) and the non-exposed (0 of 16); there was no relation between their existence and overexposures (the analysis for habitual exposure was not possible because of the small size of the sample). The risk of lens opacifications by ethylene oxide in cases of massive exposures as previously described could also exist during chronic exposure to low concentrations. It could be explained by saturation of protective mechanisms against alkylating action of this product. Linear relations were found between the logarithms of blood concentrations of polymorphoneutrophils (R=-0.54; p<0.005) and of lymphocytes (R=-0.45;p<0.05).

Early Equatorial Cataracts in Workers Exposed to Trinitrotoluene

Twelve workers (nine men and three women with a mean age of 39.5 +/- 8.9 years) with occupational exposure to trinitrotoluene had a mean duration of exposure of 6.8 +/- 4.7 years. The general physical findings were minimal, but ophthalmologic examinations showed bilateral peripheral cataracts in six of the 12 workers. Cataracts were visible only with maximal mydriasis and were continuous or annular opacities at the equator. The cataracts did not interfere with visual acuity or visual fields. Only one worker with and one without cataracts had increased serum alanine aminotransferase and bilirubin levels, possibly associated with trinitrotoluene exposure.

Die entschadigungspflichtigen Berufskrankheiten des Auges.

This is a copy of the laws adopted in Germany on April 1, 1937 on accident insurance for occupational diseases. Every physician in Germany is compelled to report each case of occupational disease that he encounters in his practice. The form in which this report should be made out is given, and the occupational diseases are described which particularly interest the ophthalmologist, such as diseases caused by lead, benzene, roentgen rays and radium, cataract in workers in glass, iron foundries and metal-smelting processes and infectious diseases occurring in persons employed in hospitals, laboratories, etc. This is an instructive article which deals with a subject that will undoubtedly be taken up more fully in this country.