Distribution of Hematologic Parameters of Complete Blood Count in Anemic and Nonanemic Children in a Mining-Exposed Highland Peruvian Community

Exposure to heavy metals from mining activities has been consistently associated with disruptions in hematologic homeostasis, adversely affecting children's overall development. We aimed to determine population-specific distributions of hematological markers and to compare anemic and nonanemic children in a mining-exposed highland community. A cross-sectional study was conducted with 156 children aged 3 to 7 years from the Peruvian highlands, using non-probability sampling and following CLSI C28-A3 guidelines for this population. Inclusion criteria were children with complete blood count results and residency in mining-contaminated areas. Blood samples were collected via venipuncture and analyzed with a 3-part Sysmex differential hematology analyzer. The mean WBC count was 10.42 ± 1.76 × 10³/µL, with no significant differences between males and females (<i>p</i> = 0.770). Hematological indices, including RBC, hemoglobin, and hematocrit levels, were consistent between sexes. However, significant differences were noted between anemic and nonanemic 3-4-year-old children for RBC (5.56 ± 0.47 vs. 7.06 ± 0.96 × 10⁶/µL) and HCT (33.97 ± 6.89 vs. 35.64 ± 5%) (each <i>p</i> < 0.00001), with lower values in anemic subjects. Also, anemic and nonanemic 5-7-year-old children had significant differences in RBC (5.87 ± 1.02 vs. 7.36 ± 0.79 × 10⁶/µL) and HCT (31.13 ± 1.73 vs. 36.54 ± 4) (each <i>p</i> < 0.00001). Our findings reveal variations in hematological parameter distributions, emphasizing the importance of personalized blood assessments for mining-exposed populations. This approach could enable earlier diagnosis and intervention for anemia among vulnerable pediatric groups.