Asbestos and Lymphoma

Asbestos, long a popular building material thanks to its durability, insulation potential, and fireproof characteristics, has only recently been implicated in the development of various kinds of lymphoma. As scientists continue to piece together the exact causal links between asbestos and lymphoma, the continued presence of asbestos in older structures dictates that the average person learn as much as possible about the relationship between the two.

The History of Asbestos

Humans have been using asbestos as a fireproofing agent for over 4000 years. Its long, fibrous crystals made it easy to weave together into cloth or packed into building materials like bricks and adobe walls. For almost as long, however, humans have made a connection between proximity to worked asbestos and shortened lifespans. It was only in the early- to mid-twentieth century that scientists discovered that airborne asbestos particles can be inhaled, lodging in the lungs and causing inflammation—a condition we call asbestosis. It was only in the last two decades or so that the link was made between the scarring that occurs with asbestosis and the development of lymphoma.

The Search for a Causal Link

An exact causal relationship between asbestos and lymphoma has not yet been established, but studies reaching back to 1982 have indicated a correlation between lymphoma patients and those exposed to asbestos. In that year, the British journal Lancet reported that participants of a study who had been exposed to asbestos had a much higher likelihood of developing large cell lymphomas, especially in the oral cavity and gastrointestinal tract. In a followup study later in 1982, a team from Los Angeles found the likelihood to be twelve times greater. So began a three-decade search for a link that may or may not exist.

According to one analysis, published in 2001, 22 studies performed between 1999 and 2000 concluded that there is a relationship between asbestos and lymphoma formation, although no study could definitively say what that relationship was. Ultimately, the meta-analysis was only able to recommend additional research.

That additional research has continued to be largely inconclusive. One major study in 2003 attempted to map the incidence of lymphoma to the geographical distribution of mesothelioma. That form of cancer, affecting the lining of the lungs, has a strong and established correlation to asbestos exposure; indeed, asbestosis is the leading cause of mesothelioma. Unfortunately, the 2003 studies found no co-occurrence of the two cancers. The authors therefore were forced to conclude that their findings did not support the lymphoma-asbestos hypothesis, although they also remarked that they did not actively disprove the hypothesis, either.

Current Research

Further research is ongoing, ranging from meta-analyses of past studies, looking for a hidden link, to longitudinal studies of factory and other workers to isolate environmental causes. Ultimately, only time will tell whether a statistically significant link does exist between asbestos and lymphoma.