EFFECT OF PB TOXIN ON ALZHEIMER'S INCIDENCE IN SURABAYA, INDONESIA

Abstract

Background: Alzheimer's disease represents a significant public health challenge globally, with environmental factors increasingly recognized as important contributors to its pathogenesis. Lead (Pb) exposure has been identified as a potential risk factor through multiple mechanisms, including oxidative stress induction. Surabaya, as Indonesia's second-largest city with substantial industrial and transportation activities, presents environmental conditions conducive to Pb pollution.

Objective: This study aimed to analyze the relationship between environmental Pb exposure, malondialdehyde (MDA) levels as an oxidative stress biomarker, and Alzheimer's incidence among residents of Surabaya.

Methods: A cross-sectional study was conducted with 100 participants selected from 150 eligible residents of Surabaya aged 60-80 years. Environmental Pb samples were collected from particulate matter (PM2.5 and PM10), while blood Pb and MDA levels were measured using atomic absorption spectrometry and the thiobarbituric acid reactive substances (TBARS) method, respectively. Alzheimer's diagnosis was confirmed using standardized cognitive assessment tools. Multiple linear regression analysis was employed with statistical significance set at p < 0.05.

Results: The study revealed significant variability in environmental Pb concentrations across Surabaya, with the highest levels detected in industrial areas (1.8 ± 0.3 μg/m³). Blood Pb levels showed a strong positive correlation with MDA concentrations (r = 0.72, p < 0.001). Participants with Alzheimer's disease exhibited significantly higher blood Pb levels (6.8 ± 1.2 μg/dL) and MDA concentrations (4.1 ± 0.8 nmol/mL) compared to healthy controls (2.1 ± 0.7 μg/dL and 1.9 ± 0.5 nmol/mL, respectively). Multiple regression analysis indicated that blood Pb levels significantly predicted both MDA levels (β = 0.61, p < 0.001) and Alzheimer's incidence (β = 0.53, p < 0.001), after adjusting for age, education, and genetic factors.

Conclusion: Environmental Pb exposure is significantly associated with increased oxidative stress and higher Alzheimer's incidence among Surabaya residents. These findings underscore the importance of implementing comprehensive environmental protection policies and public health interventions to reduce Pb exposure in urban settings.