Multichemical Exposure Assessment Using Silicone Wristbands in Central American Adolescents

Area of Science:

• Environmental Health
• Toxicology
• Nephrology

Background:

• Chronic kidney disease of uncertain etiology (CKDu) is a major health concern in Central America.
• Early-life chemical exposures are understudied, particularly in adolescents residing in CKDu high-risk areas.
• Understanding the link between environmental chemical exposure and kidney function in vulnerable populations is critical.

Purpose of the Study:

• To characterize chemical exposures in Nicaraguan adolescents living in CKDu high-risk communities.
• To identify exposure profiles and their association with kidney function, measured by estimated glomerular filtration rate (eGFR).
• To determine the contribution of individual chemicals to kidney function using machine learning.

Main Methods:

• Utilized silicone wristband passive samplers to measure exposure to over 1,500 chemicals in 80 adolescents.
• Employed k-means clustering to identify distinct exposure profiles.
• Applied LASSO logistic regression and SHAP values to analyze associations between chemical exposures and eGFR.

Main Results:

• Detected 130 chemicals, with 21 being pesticides. Pyrethroids, phthalates (DEHP, DnBP), musks (galaxolide), esters, organophosphate (TPP), and PAHs were frequently detected.
• Identified four distinct exposure profiles, with two dominated by household/personal care products.
• No single chemical showed a significant association with eGFR, but SHAP analysis highlighted phthalates, esters, organophosphates, and phenols as influential predictors of kidney function.

Conclusions:

• Nicaraguan adolescents experience varied chemical exposures, including compounds with known nephrotoxic potential.
• Phthalates, esters, organophosphates, and phenols are key predictors of kidney function in this population.
• Targeted investigation of frequently detected nephrotoxic chemicals like pyrethroids, PAHs, phenols, and phthalates is warranted.