A hematology surveillance study of petrochemical workers exposed to 1,3 butadiene

Abstract

Complete blood counts (CBC) have been recognized as an easy and readily available screen for hematotoxicity following occupational exposure to 1,3-butadiene. This study evaluated hematology data from employees who have ever participated in the Shell Butadiene Medical Surveillance Program (BMSP), compared with employees who have not participated. This study examined potential hematopoietic toxicity in relation to the occupational exposures at two Shell facilities. This study included 404 employees who participated in the BMSP, with mean butadiene exposure (TWA-8, TWA-10, and TWA-12 together) of 4.55 ppm from 1979-1996 and 0.25 ppm from 1997-2003, and 773 comparison employees. The comparison group included employees not participating in either the benzene or butadiene surveillance programs. Abnormality of six CBC parameters, including white blood cell count, red blood cell count, lymphocyte count, hemoglobin concentration, mean corpuscular volume and platelet count, and the adjusted mean values of these parameters in the exposed group were compared with those of the comparison group. We found no significantly increased abnormality for any hematology parameter among exposed employees. The adjusted mean values (adjusted for age, sex, race, length of time between first and last exam, current smoking status, and first exam value) of the exposed employees were similar to those in the comparison group. At current occupational exposure levels for 1,3-butadiene, there is no evidence of adverse hematological effects observed in this study. These findings are consistent with results of three similar studies in the literature.

Development of a Unit Risk Factor for 1,3‐Butadiene Based on an Updated Carcinogenic Toxicity Assessment

“…( 4 ) have a higher confidence than original exposure estimates. Dose‐response modeling was conducted based on the updated studies by Cheng et al ( 9 ) and Sielken et al ( 10 ) A review of the scientific literature indicated there were no other epidemiology studies ( 11,12 ) that would be appropriate to evaluate human cancer risk from BD exposure.…”

A Chronic Reference Value for 1,3-Butadiene Based on an Updated Noncancer Toxicity Assessment

“…Few adverse noncarcinogenic effects were observed other than reproductive and developmental effects, except for increases in organ weights in rats (U.S. EPA, 2002a) and hematological effects in mice exposed to higher concentrations (i.e., ≥65 ppm). Hematological effects in mice exposed to high BD concentrations may not be relevant for humans exposed to lower BD concentrations, as demonstrated by Tsai et al (2005). Tsai et al (2005) conducted a hematology surveillance study of petrochemical workers at two Shell facilities and reported there were no significantly increased abnormalities for any hematology parameter among 404 exposed employees versus 733 controls.…”

“…Hematological effects in mice exposed to high BD concentrations may not be relevant for humans exposed to lower BD concentrations, as demonstrated by Tsai et al (2005). Tsai et al (2005) conducted a hematology surveillance study of petrochemical workers at two Shell facilities and reported there were no significantly increased abnormalities for any hematology parameter among 404 exposed employees versus 733 controls. Workers were exposed to mean time-weighted average (TWA) BD concentrations of 4.55 ppm from 1979 to 1996 (TWA-8, TWA-10, and TWA-12 together) and 0.25 ppm from 1997 to 2003.…”