Hydrogen sulfide (H 2S) and sour gas effects on the eye. A historical perspective

The toxicology of hydrogen sulfide (H 2S) and sour gas on the eye has a long history beginning at least with Ramazzini's observations [Ramazzini B. Diseases of Workers—De Morbis Artificum Diatriba—1713. Wright WC (trans). New York, C. Hafner Publishing Co Inc.; 1964. 98–99 pp.]. In contrast, a recent review by Alberta Health and Wellness (AHW Report) concluded that there is little evidence of eye irritation following short-term exposures to H 2S at concentrations up to 100 ppm and that the H 2S literature on the eye is a series of unsubstantiated claims reproduced in review articles dating back to the 1930s [Alberta Health and Wellness (AHW report). Health effects associated with short-term exposure to low levels of hydrogen sulfide: a technical review, Alberta Health and Wellness, October 2002, 81pp.]. In this paper, we evaluated this claim through a historical review of the toxicology of the eye. Ramazzini noted the effects of sewer gas on the eye [Ramazzini B. Diseases of Workers—De Morbis Artificum Diatriba—1713. Wright WC (trans). New York, C. Hafner Publishing Co Inc. 1964. 98–99 pp.]. Lehmann experimentally showed eye effects in men at 70–90 ppm H 2S and also in animals [Lehmann K. Experimentalle Studien uber den Einfluss technisch und hygienisch wichtiger Gase und Dampfe auf den Organismus. Arch Hyg 1892;14:135–189]. In 1923, Sayers, Mitchell and Yant reported eye effects in animals and men at 50 ppm H 2S. Barthelemy showed eye effects in animals and men at 20 ppm H 2S [Barthelemy HL. Ten years' experience with industrial hygiene in connection with the manufacture of viscose rayon. J Ind Hyg Toxicol 1939;21:141–51]. Masure experimentally showed that H 2S is the causative agent of eye impacts in animals and men [Masure R. La Keratoconjunctivite des filatures de viscose; etude clinique and experiementale. Rev Belge Pathol 1950;20:297–341]. Michal upon microscopic examination of the rat's cornea, found nuclear pyknosis, edema and separation of cells in the eye following exposures for 3 h at 36 ppm H 2S [Michal FV. Eye lesions caused by hydrogen sulfide. Cesk Ophthalmol 1950;6;5–8]. In 1975, in Alberta, irreversible eye damage and photophobia were experimentally produced in calves exposed to 20 ppm H 2S for 1 week [Nordstrom GA. A study of calf response of ammonia and hydrogen sulfide gases. Thesis, University of Alberta, Department of Agricultural Engineering, Edmonton Alberta; 1975, 218 pp.]. Alberta Environmental Centre documented clinical irritatio