Exposure to Potentially Toxic Elements in Maternal and Umbilical Cord Blood at Ishaka Adventist Hospital, Uganda

Prenatal exposure to potentially toxic elements (PTEs), including heavy metals and metalloids, represents a significant public health concern in low- and middle-income countries where environmental monitoring is often limited. A recent study conducted at Ishaka Adventist Hospital in Bushenyi District, Uganda, assessed maternal and fetal exposure to PTEs in maternal and umbilical cord blood samples. The findings reveal important insights into exposure levels, placental transfer, and associated health risks for both mothers and newborns in this agricultural region with known environmental contamination.

Study Design and Participant Characteristics

The study analyzed maternal and umbilical cord blood samples from 32 mother-infant pairs collected at Ishaka Adventist Hospital. Researchers quantified concentrations of arsenic (As), lead (Pb), chromium (Cr), nickel (Ni), copper (Cu), iron (Fe), and zinc (Zn) using Microwave Plasma Atomic Emission Spectroscopy. Cadmium was not detected in any samples.

Maternal-Fetal Transfer of Potentially Toxic Elements

Maternal blood samples showed significantly higher imply concentrations of PTEs compared to cord blood (p < 0.05), indicating partial placental filtration. Despite this barrier, maternal-fetal transfer occurred, with transfer ratios ranging from 10.0% for zinc to 50.5% for lead. These findings demonstrate that while the placenta provides some protection, substantial fetal exposure to certain elements still occurs.

Risk Assessment and Health Implications

Weighted Risk Score modeling indicated that 68.75% of neonates and 71.88% of mothers fell into the high-risk category, primarily due to elevated levels of arsenic, lead, and chromium. Statistical analyses revealed significant associations between maternal and cord blood PTE concentrations and self-reported health issues. Notably, hypertension, respiratory allergies, gastrointestinal upsets, and gestational diabetes were correlated with higher maternal blood metal(loid) levels.

Additional factors linked to increased exposure included passive smoking, geophagia (the practice of eating soil), repeated use of mosquito coils, and use of biomass fuel such as firewood. Stratified analysis showed significantly higher chromium and lead levels among mothers reporting geophagia. Infants of older mothers and those whose mothers practiced geophagy had significantly lower birth weight, a finding also associated with elevated cord blood metal(loid) levels.

Environmental Sources and Public Health Implications

The study identified several potential environmental sources of PTE exposure in this Ugandan agricultural setting. Strong correlations between lead-copper (r = 0.75) and chromium-nickel (r = 0.52) suggest shared environmental origins for these elements. These findings underscore the need for targeted interventions to reduce exposure, particularly among vulnerable populations such as pregnant women and developing fetuses.

As environmental surveillance remains limited in many low- and middle-income countries, studies like this one provide critical data for understanding the scope of prenatal exposure to toxic elements. The results highlight the importance of addressing modifiable risk factors such as geophagia, biomass fuel use, and mosquito coil exposure to protect maternal and infant health.

Continued monitoring and public health efforts are essential to mitigate the risks associated with prenatal exposure to potentially toxic elements in similar settings worldwide.