Renal Function Assessment in Adults with Occupational Heavy Metal Exposure in Yenagoa, Bayelsa State, Nigeria

Abstract

BACKGROUND: Heavy metal exposure has been associated with numerous health effects including renal involvement. The exposure to heavy metals is still notably prevalent, and possibly on the rise particularly in some occupations. Crude oil exploration and other related industrial activities could be a contributory factor in some regions.

OBJECTIVES: The study aimed to determine the level of blood heavy metals and associated renal function of occupationally exposed persons in Yenagoa.

METHOD: Three hundred and ten (310) adults (157 study participants and 153 controls of similar age and sex) aged 18 years and above were recruited for the study via simple random sampling. The participants included smelters, auto-mechanics, vulcanizers, artisan refinery workers and petrol station attendants with each occupation categorized as clusters and non-proportionate allocation of participants for each cluster who met the inclusion criteria. The control group consisted of individuals in other occupations with less probable risk of exposure.  The participants were evaluated for Urinalysis, Serum Creatinine, Haemoglobin, blood lead and cadmium. The outcome was analyzed via descriptive statistics using version 25.0 of Statistical Package for Social Sciences (SPSS) software.

RESULTS: A total of 310 participants took part in the study with 235 (75.8%) males and 75 (24.2%) females with a male to female ratio of 3.1:1. The mean age of the study population was 35.6 ± 10.7 years with most of them between 18 to 30 years (35%). The mean level for lead and Cadmium was 48.29 ± 26.29µg/dl and 4.56 ± 3.07µg/l respectively which was higher than that of control (Pb - 27.42 ± 11.17µg/dl, Cd - 2.65 ± 1.62 µg/l). The mean eGFR was significantly lower in the exposed population, 77.39mls/min/m² as compared with control (82.57mls/min/m²). The mean Haemoglobin level was also significantly lower in the exposed populations as compared with the controls.

CONCLUSION: This study shows elevated levels of serum heavy metals in the occupationally exposed individuals with probable impact on their renal function in the Niger Delta region of Nigeria. The level of environmental exposure was also high in the control. There is a need for occupational health education to help in the prevention of excessive heavy metal exposure and curb its impact on health of all involved.