Exposure to endocrine disrupting chemicals (EDCs) or heavy metals are synthetic compounds that can lead to negative effects on health, including immune and endocrine system disruption, respiratory problems, metabolic issues, diabetes, obesity, cardiovascular problems, growth impairment, neurological and learning disabilities, and cancer. 

Petrochemical industry drilling wastes, which contain varying levels of EDCs, are known to pose a significant risk to human health. This DCU research collaboration aimed to investigate the levels of toxic elements in biological samples of individuals working in the petrochemical drilling sites. Biological samples, including scalp hair and whole blood, were collected from petrochemical drilling workers, individuals residing in the same residential area, and control age-matched persons from nonindustrial areas. 

The samples were oxidized by an acid mixture before analysis using atomic absorption spectrophotometry. The accuracy and validity of the methodology were verified through certified reference materials from scalp hair and whole blood. The results showed that the concentrations of toxic elements, such as cadmium and lead, were higher in biological samples of petrochemical drilling employees, while lower essential element levels (iron and zinc) were detected in their samples.