A Study of the Relationships Between Proximity to an Industrial Complex and Blood Lead Levels and Urinary Cadmium Levels

Abstract

Background: Most people spend their time in their house, and live around their residence. So, we supposed that their exposure levels were associated with the location of residence. Aims: The goal of this study was to investigate the relationships between proximity to an industrial complex and blood lead levels and urinary cadmium levels. Methods: We conducted a questionnaire survey and analyzed blood lead and urinary cadmium levels using Atomic Absorption Spectrometry (AAs). Data was analyzed using logistic regression analysis. The distance between the residence and an industrial complex was calculated through a Geographical Information System (GIS). Results: A total of 967 residents living near a large petrochemical complex in Ulsan participated. The geometric mean levels of blood lead and urinary cadmium were 1.70 ?g/dl (male: 1.77 ?g/dl, female: 1.67 ?g/dl), and 0.72 ?g/g creatinine (male: 0.49 ?g/g cr. female: 0.89 ?g/g cr.), respectively. Blood lead and urinary cadmium levels both increased with age and were higher among smokers compared to never smokers.Results from multiple logistic regression analysis showed that urinary cadmium levels for subjects aged less than 20 years old were negatively associated with distance from the industrial area to the residence (OR=1.09[1.05-1.14]). The results, however, indicated that the blood lead levels were positively associated with the distance (OR=0.77[0.70-0.82]) Conclusions: The results of this study support that proximity to an industrial complex is related to urinary cadmium values for children. A positive finding with blood lead can be explained by the ambiguity of lead exposure sources in the general environment.