Association Between Self-Reported Symptoms and Biological Measures of Heavy Metal Exposure

Purpose. The objective of this study was to evaluate the relationship between self-reported symptoms and biomarkers of lead and cadmium in urine and blood of people exposed to these heavy metals. Methodology. Blood and urine measures of lead and cadmium were grouped into quartiles. A correlation matrix was created to assess the linear relationship between urine and blood levels of metals and a scatter plot was used to visualize this relationship. A chi-square test was then used to assess independence between the frequencies of self-reported symptoms by quartiles of biological measures. Logistic regression was used to analyze the relationship between symptoms in the lowest quartile compared with those in higher quartiles. Results.There was a significant (p Conclusion. This study shows that there is a positive relationship between self-reported symptoms and biological measures of heavy metal exposure, where those with higher exposures to heavy metals experienced more symptoms. There is also a significant association between lead levels in urine and blood.