GIS based interpolation method to urinary metal concentrations in Malaysia

Area of Science:

• Environmental Health
• Toxicology
• Public Health

Background:

• Environmental contamination by heavy metals like arsenic (As), cadmium (Cd), nickel (Ni), and lead (Pb) poses significant ecological and global public health risks.
• Understanding the spatial distribution of these toxic elements in human populations is crucial for targeted interventions.

Purpose of the Study:

• To visualize the geographical distribution of arsenic, cadmium, nickel, and lead concentrations in the urine of Malaysian adults.
• To identify regions with higher heavy metal exposure levels within Malaysia.

Main Methods:

• A cross-sectional study involving 817 Malaysian adults, with urine samples collected between October 2017 and March 2018.
• Spatial Inverse Distance Weighted (IDW) interpolation was employed to map metal concentrations.
• Moran's I Index was utilized to assess spatial autocorrelation of heavy metals.

Main Results:

• Highest mean concentrations of nickel (Ni) and cadmium (Cd) were observed in Perak.
• Arsenic (As) and lead (Pb) were predominantly found in the East Coast region (Terengganu and Kelantan).
• Significant spatial autocorrelation was detected for As, Cd, and Ni, but not for Pb.
• IDW mapping indicated elevated As and Cd levels in the North East and Western regions, with lower exposure in Central compared to North regions.

Conclusions:

• Geospatial analysis effectively visualizes heavy metal exposure patterns in a population.
• Identifying regional hotspots for specific heavy metals aids health authorities in predicting exposure and prioritizing control measures.
• The findings highlight the need for targeted public health strategies to mitigate heavy metal exposure in Malaysia.