Profile of Haematological Parameters among Radiographers Exposed to Low-Dose X-Rays in Selected Port Harcourt Healthcare Facilities

Abstract

X-rays are electromagnetic waves that can traverse the human body due to high energies (≥1.24 keV) and ultra-short wavelengths (≤10-10m). Acute exposures are harmful to human health, affecting hematopoietic systems among others. Workers experience these effects despite use of occupational exposure controls such as Personal Protective Equipment (PPEs). This study spanned May 2018 to February 2019, and was aimed at determining the effects of exposure to low-dose x-rays on haematological parameters of radiographers in Port-Harcourt. Delimitation was to a target population of radiographers who work for ≥ 6-hours daily and ≥ 5-days weekly, over ≥ 12-months, and a corresponding number of control subjects in five healthcare facilities. The cross-sectional retrospective comparative research design method was employed, and consisted of administered Questionnaire with a 100% response rate. Two sets of blood samples, collected 120 days apart, underwent clinical laboratory examinations.  30 exposed (case) and 30 unexposed (control) subjects, aged 25-54 years, participated in this study at a ratio of 1:1. Mean annual background x-ray room radiation level was 0.7724mSv (i.e. 0.6088mSv-0.8392mSv), and workers recorded 100% usage of PPEs and 86.7% (n=26) knowledge/awareness to adverse x-ray effects. Mean values for hematocrit, platelet, and mean cell volume, were higher, but White Blood Cells (WBCs) (P=0.025, 0.044), Neutrophils (P=0.018, 0.042), Lymphocytes (P=0.026, 0.025) were significantly lower, in the case vis-à-vis control groups. Haematological parameters showed no statistical differences between values for 1st and 2nd sample sets within each subject group. Normal blood cell morphologies predominated in the unexposed group (76.6% & 86.7%), when compared to the exposed group (53.3% & 50.0%), except for codocytes (z = -1.000, P=0.317). WBC values in radiographers inversely correlated with their duration of x-ray exposures (r = -0.431, P˂0.05).This study showed that chronic exposures to low-dose x-rays affect whole leucocyte parameters, despite implementation of PPEs.