lewisite and Lung-Neoplasms

The vesicant agents of the unitary chemical munitions stockpile include various formulations of sulfur mustard [bis-(2-chloroethyl) sulfide; agents H, HD, and HT] and small quantities of the organic arsenical Lewisite [dichloro(2-chlorovinyl) arsine; agent L]. These agents can be dispersed in liquid, aerosol, or vapor form and are capable of producing severe chemical burns upon direct contact with tissue. Moist tissues such as the eyes, respiratory tract, and axillary areas are particularly affected. Available data summarizing acute dose response in humans and laboratory animals are summarized. Vesicant agents are also capable of generating delayed effects such as chronic bronchitis, carcinogenesis, or keratitis/keratopathy of the eye under appropriate conditions of exposure and dose. These effects may not become manifest until years following exposure. Risk analysis derived from carcinogenesis data indicates that sulfur mustard possesses a carcinogenic potency similar to that of benzo[a]pyrene. Because mustard agents are alkylating compounds, they destroy individual cells by reaction with cellular proteins, enzymes, RNA, and DNA. Once begun, tissue reaction is irreversible. Mustard agents are mutagenic; data for cellular and laboratory animal assays are presented. Reproductive effects have not been demonstrated in the offspring of laboratory rats. Acute Lewisite exposure has been implicated in cases of Bowen's disease, an intraepidermal squamous cell carcinoma. Lewisite is not known to generate reproductive or teratogenic effects.

Topics: Animals; Arsenic Poisoning; Arsenicals; Cell Membrane Permeability; Chemical Warfare; Dermatitis, Irritant; DNA Damage; Female; Humans; Irritants; Keratitis; Lethal Dose 50; Lung Neoplasms; Male; Mustard Gas; Mutation; Pregnancy; Reproduction; Respiratory Tract Diseases

Sulfur mustard, an agent used in chemical warfare, is an alkylating substance with carcinogenic potential. However, the precise long-term carcinogenic effects of mustard gas are unclear. Since 1952, the authors have conducted health surveys of former workers who were employed from 1929 to 1945 in a poisonous gas factory in Okuno-jima, Hiroshima, Japan. This prospective study was undertaken from 1952 to 2005 to examine the incidence of lung cancer among the workers who were exposed to mustard gas (n=480), lewisite (n=55), and/or diphenylcyanarsine (n=178), as well as the incidence among unexposed workers (n=969). The stochastic relation between exposure and lung cancer was explored on the basis of multistage carcinogenesis by using an accelerated hazard model with a transformed age scale. Mustard gas exposure was found to transform the age scale for developing lung cancer. One year of exposure in subjects ≤18 or >18 years old at first exposure shifted the age scale down by 4.9 years and 3.3 years, respectively. On the basis of the long-term follow-up of former workers in the poisonous gas factory, the authors concluded that sulfur mustard decreased the age at which people were at risk of developing lung cancer and that the effect declined with aging.

Topics: Age Factors; Arsenicals; Chemical Industry; Humans; Incidence; Japan; Longitudinal Studies; Lung Neoplasms; Male; Mustard Gas; Occupational Exposure; Odds Ratio; Smoking; Surveys and Questionnaires; Time Factors; Young Adult

Topics: Adenocarcinoma; Arsenicals; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Chemical Industry; Follow-Up Studies; Humans; Japan; Lung Neoplasms; Male; Mustard Gas; Occupational Diseases; Respiratory Tract Neoplasms; Smoking