The occupation or industry in which one works may either increase or decrease risk for non-Hodgkin's lymphoma, an immune system cancer often found in middle-aged adults.

An analysis of newly diagnosed non-Hodgkin's lymphoma (NHL) cases diagnosed between July 1998 and June 2000 confirms previous reports of increased risk for NHL among farmers, printers, leather workers, medical professionals, and some electronic workers, researchers report in the journal Occupational and Environmental Medicine.

However, "it is not the job title or industry that causes the increased risk, but rather the specific exposures to chemical and biologic agents in the work place that may increase the risk of NHL," Dr. Maryjean Schenk told Reuters Health.

Schenk, of Wayne State University in Detroit, Michigan and colleagues compared the types of jobs reported by 1189 men and women who were between 20 and 74 years old when diagnosed with NHL, and the jobs of 982 men and women of similar age who did not have NHL.

Overall, the investigators analyzed NHL risk in 86 occupations and 97 industries.

Besides those mentioned above, the investigators report an increased risk for NHL among religious workers, physical therapists, information clerks, purchasing agents and buyers, as well as workers in service, nursing/personal care, specialty outpatient care, and air transportation occupations.

They also found increased NHL risk among launderers/ironers, roofers and siders, hand packers and packagers, and food/beverage preparation supervisors.

By contrast, Schenk's group identified decreased risk among industrial production managers, post-secondary teachers, editors, reporters, and those working in public relations, financial records, administrative support, security and commodities, accident and health insurance, and medical and personal supply jobs.

They also found decreased risk of NHL among general merchandise, chemical and allied products industries, and jobs dealing with non-computer related electronics, and household appliances and hardware.

Schenk and colleagues say it is important to identify occupations and industries associated with increased risk for NHL. The information "can be utilized to further investigate these occupations and industries for specific exposures that may increase the risk of NHL," Schenk said.