COMPARISON OF EMPLOYEES WHITE BLOOD-CELL COUNTS IN A PETROCHEMICAL PLANT BY WORKSITE AND RACE

To determine, if employment within a petrochemical plant's quality con trol (QC) laboratory had any significant effect on the hematopoietic s ystem, and in specific, the white blood cell (WBC) counts, all employe es of the QC laboratory were evaluated retrospectively. Trend analysis , linear regression, and Student's t tests were performed on all emplo yees of the QC laboratory and on a simple random sample of the rest of this Caribbean petrochemical plant's male employees. Trend analyses r evealed a downward trend in 82.6% of the QC laboratory workers and 76. 7% in other plant workers. Linear regression and t tests revealed no s tatistically significant difference by worksite but a significant diff erence between blacks and whites. The result of the findings of the QC laboratory workers was consistent with that expected in both plant em ployees and the US general population. A recommendation is made that t he Occupational Safety and Health Administration (OSHA) reconsider its WBC cutoff level in the benzene standard.