Assessment of Haematological Parameters in Students Residing Near a Steel Rolling Mill in Ajaokuta, Kogi State, North Central Nigeria

This study assesses haematological parameters in secondary school students residing in communities adjacent to the Ajaokuta Steel Rolling Mill, Kogi State, North Central Nigeria, evaluating the potential haematological impact of heavy metal pollution from steel manufacturing. Industrial emissions from steel rolling mills, including lead, cadmium, and particulate matter, can impair erythropoiesis and blood cell function. A cross-sectional study compared haematological parameters of 150 students living within two kilometres of the mill with 75 students from a non-industrial control community 15 kilometres away, matched by age, sex, and socioeconomic status. Full blood count, blood lead levels (by atomic absorption spectrophotometry), and zinc protoporphyrin were assessed as markers of lead exposure and iron utilisation impairment. Results showed significantly lower haemoglobin, red blood cell count, and MCV in mill-adjacent students compared to controls. Blood lead levels were significantly elevated in the exposed group (mean 18.4 micrograms per decilitre vs 6.2 micrograms per decilitre in controls), exceeding the reference threshold of 5 micrograms per decilitre. Zinc protoporphyrin was correspondingly elevated in the exposed group. The study recommends environmental remediation around the mill, provision of protective measures for nearby residents, and regular haematological and blood lead screening for communities around industrial sites in Kogi State. Keywords: steel mill, heavy metal pollution, lead exposure, haematological parameters, Ajaokuta.