Haematological, renal, and hepatic function changes among Rayong oil spill clean-up workers: a longitudinal study

The Rayong oil spill incident of 2013 leaked over 50,000 barrels of crude oil into the Gulf of Thailand. This study assessed trends and changes in the haematological, renal, and hepatic indices among the Rayong oil spill clean-up workers 5 years after the spill.

Haematological, renal, and hepatic indices measured for 570 oil spill clean-up workers at baseline and annually during 5-year follow-ups were analysed. Haemoglobin (Hb), haematocrit (Hct), white blood cell (WBC) count, red blood cell (RBC) count, and platelet count for haematological function, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) for hepatic function, and creatinine (Cr) and blood urea nitrogen (BUN) for renal function were assessed. The longitudinal measures of haematological, renal and hepatic indices were analysed using analysis of variance for repeated measures. The generalised estimating equations (GEE) were used to assess trends of these indices and associated factors, including exposure level.

Increasing trends were observed per year for WBC (0.52 ± 0.03 × 10³ cells/μL), Cr (0.01 ± 0.00 mg/dL), platelet (0.31 × 10³ μL per year), and BUN (0.24 ± 0.03 mg/dL). Decreasing trends of aspartate aminotransferase (AST) were observed (1.54 ± 0.21 IU/L per year). Clean-up workers with high exposure to the oil spill had a significantly higher average of WBC and lower average of BUN than low-exposure and unknown-exposure workers. Gender and age were significantly associated with creatinine changes.

Results of this study show the differences between baseline and follow-up haematological, renal, and hepatic indices and trends of these indices. The long-term changes in the indices in this study show worsening renal functions after oil spill and possibility of cardiovascular effects. These findings contribute to expanding knowledge on the long-term health effects of oil spills.