Abstract
Objective: There is a paucity of evidence on the lead exposure and blood pressure association in Nigeria where lead exposure is still prevalent and poorly regulated. The objective of this study was to evaluate the association between lead exposure using blood lead level and blood pressure in Port Harcourt Nigeria. Methodology: A prospective cross sectional comparative study of adult subjects with occupational lead exposure and controls, performed in Port Harcourt, South-south Nigeria. Blood lead measured by atomic absorption spectrophotometry was used as the biomarker of lead exposure while systolic and diastolic blood pressures and other relevant variables were measured and analysed. Results: The mean systolic blood pressure was significantly higher in lead exposed subjects 118.49 (14.67) mmHg compared to controls 113.62 (11.31) mmHg (p = 0.008). No difference was observed in the mean diastolic blood pressure. A higher proportion of subjects had systolic and diastolic pressure > 140 mmHg and >90 mmHg compared to controls 9.47% vs. 1.25% and 10.51% vs. 2.54%, with (p = 0.016), OR = 8.27 , RR = 1.38 and (p = 0.028), OR = 4.59 , RR = 1.33 respectively. There was no significant statistical correlation between blood lead and blood pressure. Conclusion: The results of this study indicate a significant systolic blood pressure elevation and prevalence of hypertension among lead exposed workers in Port Harcourt Nigeria. Lager longitudinal research is needed to evaluate lead exposure and elevated blood pressure association in Nigeria. The findings call for better regulation of occupational lead exposure in Nigeria.
Highlights
Occupational and environmental lead exposure has been associated with blood pressure elevation [1]
This study which evaluated the relationship of blood lead and blood pressure among lead exposed workers established a significantly higher degree of lead exposure in the study subjects compared to controls as demonstrated by significantly higher mean blood lead levels (BLL) in study subjects compared to controls 50.3 ± 24.5 ug/dl vs. 41.40 ± 26.85 ug/dl
This finding is consistent with reports from other Nigerian studies reporting higher mean BLL in occupationally exposed populations compared to controls of 56.3 ± 0.95 ug/dl vs 30.47 ± 1.4 ug/dl [47], 48.09 ± 9.08 ug/dl vs 33.65 ± 10.09 ug/dl [48] and 46.0 ± 0.19 ug/dl vs 31.0 ± 0.10 ug/dl [38] respectively
Summary
Occupational and environmental lead exposure has been associated with blood pressure elevation [1]. Several epidemiologic studies [5] [6] [7] [8] [9] have shown that relatively low level of lead exposure is associated with a significant increase in blood pressure. This epidemiological association of lead exposure and elevated blood pressure has been shown to contribute largely to the disease burden attributable to lead, as a result of its associated cardiovascular risk [10] [11]. The NHANES III survey showed that lead level remains significantly and positively related to elevated BP and hypertension among blacks, who had higher blood lead concentrations compared with whites [16]. The positive correlation between increasing lead exposure biomarkers and hypertension has been demonstrated in many studies globally as shown in reports from the NHANES II survey [17] [18] and other studies in Spain [19], China [20], Kenya [21], Nigeria [22] Japan [23] and Saudi Arabia [24]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call