A new, peer-reviewed article in Cancer (paywall) proffers evidence suggesting material increased risks of non-Hodgkin lymphoma in persons leaving in proximity to Georgia refineries and manufacturing plants that release benzene. The Science Daily summary states the following:
"July 29, 2013 — The incidence of a particular type of blood cancer is significantly higher in regions near facilities that release the chemical benzene into the environment. That is the conclusion of a new study published early online in Cancer, a peer-reviewed journal of the American Cancer Society. This and other studies like it will be critical to identifying and enacting public health policies to decrease or prevent cancer.
Non-Hodgkin lymphoma has been on the rise over the past few decades as industrial production in the United States has expanded. Benzene is one chemical carcinogen linked to blood cancers. Working with Dr. Christopher Flowers and colleagues in the Lymphoma Program at Emory University in Atlanta, Catherine Bulka, MPH, used publicly available data from the Environmental Protection Agency and the US Census Bureau to analyse the geographic patterns of non-Hodgkin lymphoma cases in the state of Georgia between 1999 and 2008. This group examined the associations between new cases of lymphoma and the locations of facilities — such as petroleum refineries and manufacturing plants — that released benzene into the surrounding air or water.
The investigators found that the metro-Atlanta region, Augusta, and Savannah had the highest incidence of non-Hodgkin lymphoma even when controlling for population size as well as for age, sex, and race demographics of the local region. Also, the incidence of non-Hodgkin lymphoma was significantly greater than expected surrounding benzene release sites located in the metro-Atlanta area and surrounding one benzene release site in Savannah. For every mile the average distance to benzene release sites increased, there was a 0.31 percent decrease in the risk of non-Hodgkin lymphoma.
"Our study is the first to examine the relationship between passive benzene exposure and the incidence of non-Hodgkin lymphoma at the state population level," said Bulka. "Our findings are limited without similar studies to corroborate our results, but we hope that our research will inform readers of the potential risks of living near facilities that release carcinogens into the air, groundwater, or soil," she added."
The abstract to the article states:
"BACKGROUND
An increased risk of non-Hodgkin lymphoma (NHL) has been observed among individuals with occupational exposure to benzene, but the risk among those living near benzene release sites has not been well described.
METHODS
To investigate the spatial patterns of NHL incidence and the association between NHL incidence and distance to benzene release sites, the authors linked and geocoded data on benzene release sites in Georgia from 1988 to 1998 using the Environmental Protection Agency’s (EPA) Toxics Release Inventory (TRI), census tract level population statistics, and NHL incidence from the Georgia Comprehensive Cancer Registry (GCCR) from 1999 to 2008. Standardized incidence ratios were mapped by census tract, and a Poisson regression was performed on NHL and NHL subtype incidence data using the mean distance between the tract centroids and release sites as markers of exposure. Cluster analyses were conducted at the global, local, and focal levels.
RESULTS
Poisson regression indicated that, for every mile the average distance to benzene release sites increased, there was an expected 0.31% decrease in the risk of NHL. Similar results were observed for all NHL subtypes analyzed. Clusters of NHL were spatially associated with benzene release sites located in metropolitan areas, but not with release sites in other areas of the state.
CONCLUSIONS
NHL incidence was significantly higher in census tracts that were closer, on average, to benzene release sites. Additional studies are needed to examine spatial patterns of NHL incidence in other geographic regions and interactions between benzene and other exposures. Cancer 2013. © 2013 American Cancer Society."