Doenças Cardiovasculares e Diagnóstico

Effects of Quarry Dusts on the Electrocardiogram of Quarry Workers in Abakaliki Metropolis

Abstract

Ottah-Umahi G, Ezeja GU , Okorocha  AE, Anwara C , Agwu UM , Onwudiwe CU , Nwodo DO, Ugwu O, Okike PO

Associations between high level of occupational dust and cardiovascular diseases have been known for more than half a century. This study aims to evaluate the effects of quarry dusts on the electrocardiogram of quarry workers in Abakaliki metropolis. 100 workers from quarry industry (test group) and 100 civil servants (control group) participated in this study. They were within the age of 18 to 65 years. A questionnaire was issued to obtain some vital medical and workplace information. Signed consents forms were obtained. An electrocardiogram machine was used to examine the electrical activities of their hearts. Data were presented as Mean ± SEM, analyzed using a 2- way ANOVA, and a multiple comparison test using Tukey's Post Hoc Test. Level of significance was set at p<0.05. All statistical analyses were carried out using Graph Pad prism 7 software. The result showed no significant difference in the QRS duration, QT interval, QTC interval, RV5 and SV1 amplitudes of quarry workers when compared with control. Significant increase was observed in the PR- intervals of quarry machine operators (p= 0.0219), quarry stone carriers (p=0.0316) and quarry stone crushers (p=0.0259) when compared with the control. Furthermore, significant decrease in the p value- axis of quarry machine operators (p=0.0001), quarry stone carriers (p=0.0001) and quarry stone crushers (p=0.0001) when compared with the control was detected. The result also showed a significant increase in the QRS- axis of quarry machine operators (p=0.0258), quarry stone carriers (p=0.0346) and quarry stone crushers (p=0.0467) when compared with the control. Additionally, among the different groups of quarry workers, quarry machine operators recorded prolonged PR intervals and a significant decrease in T-axis when compared with other quarry workers. In conclusion, quarry workers have inadequate PR – Interval, QRS axis and P axis than non-quarry workers thus have compromised electrical activities of their hearts. Also, prolonged PR- interval recorded by the quarry machine operators when compared with other groups of quarry workers is an indication that greater exposure to quarry dust may cause greater damage to the heart. Quarry workers need to be encouraged to adopt cardiovascular health safety strategies and also, be educated on quarry dusts hazards.