Abstract Objective: To correlate the levels of bladder tumour antigen (BTA) with aflatoxin M1 (AFM) in a human population in Nigeria. 23 24 Subjects and methods: A pilot, observational study was conducted with 22 human subjects randomly recruited from a Nigerian rural community. Serum and first morning urine of participants were analysed for human BTA and AFM1, respectively, using quantitative ELISA assays. 25 26 27 Results: All the subjects were positive to AFM1 (mean = 0.235 ± 0.072 ng/mL) while 19 were positive to BTA (mean = 2.340 ± 1.741 ng/mL). A negative relationship occurred between human BTA and AFM level (r = ?0.239; P = 0.285). Human BTA (2.86 ± 2.43 ng/mL; P = 0.306) and AFM1 (0.258 ± 0.065 ng/mL; P = 0.643) were higher in subjects 1–20 years. The two biomarkers were not also associated with sexes of the participants (P>0.05), although they were higher in the female subjects.