Determinants of blood lead and cadmium levels in sanitary landfill workers: a cross-sectional study in Greece

Background-aim Landfill workers face a range of occupational exposures that can adversely affect their health and overall quality of life. The aim of this study was to assess cadmium and lead concentrations in the blood of workers employed at sanitary landfill sites, while documenting additional health indicators. Another objective was to explore potential associations between exposure levels and demographic factors, occupational history, working conditions. Methods A cross-sectional study was conducted among employees working at four landfill sites in Northern Greece. Participants completed a questionnaire and underwent clinical examination. Blood samples were collected for hematological, biochemical analyses, and the determination of lead and cadmium concentrations. Statistical analyses were performed to identify differences in the examined parameters across occupational exposure groups and to identify predictors of lead and cadmium levels. Results A total of 147 employees were recruited (76.9% males, n = 113), with a mean age of 48 ± 7.6 years. Blood lead levels were significantly higher in males compared to females (2.26 μg/dL vs. 1.40 μg/dL, p = 0.001), while no sex differences were observed for cadmium ( p = 0.438). Increasing age was associated with higher lead levels ( p = 0.001), but not with cadmium ( p = 0.382). Cadmium levels increased with higher BMI, whereas lead levels decreased (normal weight: 2.24 ± 1.67 μg/dL and 1.25 ± 1.33 μg/L; overweight: 2.05 ± 1.33 μg/dL and 1.41 ± 1.97 μg/L; obese: 1.88 ± 1.15 μg/dL and 1.45 ± 1.89 μg/L, respectively). Smoking was a significant determinant of both metals, with higher levels observed among smokers (lead: 1.61 ± 0.98 μg/dL; cadmium: 0.50 ± 0.71 μg/L). Significant predictors of cadmium and lead levels included smoking, duration of employment, work position, occupational site and use of personal protective equipment (PPE). Highly exposed workers had significantly higher cadmium (2.12 ± 2.38 μg/L) and lead levels (2.69 ± 1.61 μg/dL) compared to moderate and low exposure groups ( p ≤ 0.016). Conclusion Blood cadmium and lead levels among landfill workers were associated with occupational exposure intensity and individual factors such as age, BMI, and smoking. Although overall concentrations were relatively low, cumulative exposure influenced by both workplace conditions and lifestyle factors is evident. These findings underscore the need for ongoing occupational health monitoring and targeted preventive measures to reduce exposure and protect worker health.