Steelmaking is an anthropogenic activity contributing to the emission of lead into the environment. Lead, a non-essential and bioaccumulative metal, can cause adverse effects on human health. This study aimed to assess the biomarkers of exposure (lead concentration in blood, plasma, and urine), effect (delta-aminolevulinic acid dehydratase (ALAD) activity), and susceptibility (polymorphism rs1800435) to lead in residents exposed to steel industry waste in a condominium in the city of Volta Redonda, Rio de Janeiro, Brazil. Lead levels were measured in blood (BPb), plasma (PPb), and urine (UPb) using a graphite furnace atomic absorption spectrometer (GFAAS), while ALAD activity, and genotyping by spectrophotometry and RT-PCR, respectively. Twenty-seven individuals were assessed who showed a mean blood lead of 2.13±0.80 µg dL^-1, plasma lead equal to 2.80±2.61 µg L^-1, urinary lead of 4.35±4.31 µg g^-1 creatinine, and an ALAD activity of 24.45±8.28 U L^-1. The genotypical frequencies for the polymorphism rs1800435 were ALAD 1-1 (92.52%), ALAD 1-2 (7.40%), ALAD 2-2 (0.00%), while their allelic frequencies were 96.30% for the wild-type allele c, and 0.0370% for the polymorphous allele g. The results suggest that those individuals were environmentally exposed to lead.