Hematological and hepatic alterations in nonsmoking residents exposed to benzene following a flaring incident at the British petroleum plant in Texas City

Abstract

Objective: Human exposure to benzene is associated with multiple adverse health effects with an increased risk of developing carcinogenesis. Benzene exposure is known to affect many critical organs including the hematological, hepatic, renal, lung, and cardiac functions. The purpose of this study is to examine the health effects of benzene exposure among nonsmoking subjects from a prolonged flaring incident that occurred at the British petroleum (BP) refinery in the Texas City, Texas.

Methods: The study included nonsmoking subjects who had been exposed and unexposed to benzene. Using medical charts, clinical data including white blood cell (WBC) counts, platelet counts, hemoglobin, hematocrit, blood urea nitrogen (BUN), creatinine, alkaline phosphatase (ALP), aspartate amino transferase (AST), and alanine amino transferase (ALT) in nonsmoking subjects exposed to benzene were reviewed and analyzed and compared with unexposed adults.

Results: A total of 1422 nonsmoking subjects (benzene exposed, n=1093 and unexposed, n=329) were included. Benzene exposed subjects had significantly higher levels of WBC (×10(3) per μL) counts (7.7±2.2 versus 6.8±1.7, P=0.001) and platelet (×10(3) per μL) counts (288.8±59.0 versus 245.3±54.4, P=0.001) compared with the unexposed subjects. The mean serum creatinine (mg/dL) levels were also significantly increased in the benzene exposed group compared with the unexposed group (1.1±0.4 versus 0.8±0.2, P=0.001). Serum levels of ALP (IU/L) was significantly elevated in the benzene exposed subjects compared with the unexposed subjects (87.3±22.6 versus 69.6±16.5, P=0.001). Similarly, benzene exposed subjects had significantly higher levels of AST and ALT compared with those unexposed subjects.

Conclusion: Benzene exposure from the prolonged BP flaring incident caused significant alterations in hematological and liver markers indicating that these nonsmoking residents exposed to refinery chemicals may be at a higher risk of developing hepatic or blood related disorders.

Figure 1

Map showing the location of the incident of British petroleum (BP) refinery that spewed hundreds of thousands of pounds of toxic chemicals including benzene and carbon monoxide into the skies of Texas City, Texas for 40 days from April 6 to May 16, 2010. During the incident, the wind originated from south to north and dispersed the discharged benzene impacting the people residing in the northern parts of the Texas City. A. Location of Texas City, Texas. B. Depicted intensity of benzene exposure from BP incident surrounding neighborhoods of Texas City, Texas. The red, orange, and yellow colors depict the higher (red) to reduced (orange) to low (yellow) intensity of benzene exposure. C. Scattered dots represent the location/address of the study participants who were exposed to benzene following a flaring incident at the BP refinery and surrounding areas. D. A closer look at the affected area by the benzene exposure and the location of study participants (scattered dots).