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Health consequences of involuntary exposure to benzene following a flaring incident at British Petroleum refinery in Texas City

Mark A. D’Andrea, MD, FACRO, Omesh Singh, DO, G. Kesava Reddy, PhD, MHA


Objective: Environmental exposure to benzene can lead to deleterious effects on many biological systems including blood-forming organs, liver, and kidneys. The authors sought to investigate the health consequences of benzene exposure following a flaring incident that occurred at the British Petroleum (BP) refinery in Texas City, TX.
Subjects and participants: A cohort of subjects who were exposed to a daily sustained release of toxic chemicals including more than 7,711 kg (17,000 lb) of benzene for a total duration of 40 days due to BP’s flaring incident.
Interventions: Not applicable to an observational study.
Methods: Subjects who underwent physical and clinical evaluation between June 2010 and October 2012 were included. Demographic and clinical laboratory data were collected and analyzed. Hematologic data such as white blood cell (WBC) counts, platelet counts, hemoglobin, hematocrit, blood urea nitrogen (BUN), and creatinine levels in the serum were evaluated. In addition, data on alkaline phosphatase (ALP), aspartate amino transferase (AST), and alanine amino transferase (ALT) levels in the serum were examined. Urinary phenol was evaluated as a benzene metabolite. The outcomes were compared between exposed and unexposed patients.
Results: A total of 200 subjects (benzene exposed, n = 100 and unexposed, n = 100) were included. Benzene exposed subjects showed significantly higher levels of WBC (×103 per μL) count (8.6 ± 5.4 vs 6.5 ± 2.0, p = 0.0003) and platelet (×103 per μL) count (291.3 ± 82.7 vs 264.1 ± 74.0, p = 0.0076) compared with the unexposed subjects. ALP (IU/L) was significantly elevated in the benzene exposed subjects compared with the unexposed subjects (121.2 ± 73.7 vs 65.4 ± 23.6, p = 0.000). Similarly, benzene exposed subjects had significantly higher levels of AST (IU/L) compared with unexposed subjects (23.4 ± 11.8 vs 19.5 ± 8.9, p = 0.0089).
Conclusion: This retrospective pilot study found that environmental benzene exposure from the BP’s flaring incident appears to pose significant health risks including specific alteration of blood cells and liver enzymes, indicating that subjects exposed to benzene may be at a higher risk of developing hepatic or blood related disorders.


benzene poisoning, blood disorders, chemical exposure, health impact, hematologic toxicity, hepatotoxicity, petroleum refinery, urinary metabolites of benzene

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