Assessment of Pollution Load Index and Possible Ecological Risks of Heavy Metal Pollution on Petroleum Products Workers

Occupational workers handling cooking gas and heating kerosene in open yards may be exposed to various heavy metal ions emitted from these petroleum products. This study aimed to assess the blood concentrations of lead (Pb), copper (Cu), and zinc (Zn) among workers from 8 randomly selected petroleum product yards in Baghdad Province, Iraq, between January and May 2024. A total of 30 workers, with varying durations of employment, were included in the study, alongside a control group of 20 individuals., Additionally, soil samples from all sites were collected to evaluate heavy metal contamination and determine the Pollution Load Index (PLI) using a flame atomic absorption spectrophotometer. The obtained results indicated that the soil at all study sites was classified as having deteriorated on-site quality due to heavy metal contamination. No significant correlation was observed between age and blood heavy metal concentrations. However, there were highly significant differences (P≤0.001) in the concentrations of all examined heavy metals between occupational workers and the control group. The mean blood concentrations in the control sample were 15.335±3.299 µg.dL-1 of Pb, 125.55±22.377 µg.dL-1 of Cu and 99.1± 13.824 µg.dL-1 of Zn, while in workers, they were 52.4±5.516 µg.dL-1 of Pb, 157.3± 22.569 µg.dL-1 of Cu and 114.93±12.686 µg.dL-1 of Zn. This also identified a significant association (P≤0.01) between smoking and increased blood heavy metal concentrations. Smoking workers exhibited significantly higher heavy metal levels (P≤0.05) compared to nonsmokers. The duration of employment had a clear and significant (P≤0.01) impact on blood heavy metal levels. Yet, significant differences were found in some hematological parameters of workers via complete blood count. In conclusion, the findings confirm that soil at all study sites was polluted with heavy metals, which posed health risks to workers who came into direct contact with petroleum products, as reflected in their altered blood parameters.