Benzena merupakan senyawa hidrokarbon aromatik volatil yang banyak ditemukan pada industri minyak dan gas bumi serta telah diklasifikasikan sebagai karsinogen Grup 1 oleh International Agency for Research on Cancer (IARC). Pajanan benzena pada pekerja sektor hulu migas berpotensi menimbulkan gangguan kesehatan, terutama pada sistem hematopoietik, serta meningkatkan risiko leukemia akibat pajanan kronis. Penilaian risiko pajanan benzena umumnya masih berfokus pada pemantauan lingkungan kerja sehingga belum sepenuhnya menggambarkan dosis internal yang diterima pekerja. Oleh karena itu, diperlukan pendekatan yang mengintegrasikan pemantauan lingkungan kerja dan biomonitoring untuk memperoleh gambaran risiko yang lebih komprehensif. Penelitian ini bertujuan menganalisis risiko pajanan benzena pada pekerja sektor hulu minyak dan gas bumi menggunakan pendekatan Chemical Health Risk Assessment (CHRA) yang terintegrasi dengan area monitoring, personal monitoring, dan biomonitoring. Penelitian ini menggunakan desain observasional retrospektif berbasis data sekunder yang diperoleh dari program pemantauan lingkungan kerja dan biomonitoring perusahaan. Analisis dilakukan pada pekerja yang dikelompokkan berdasarkan Similar Exposure Group (SEG), yaitu Proses, IPAL, Laboratorium, dan Support. Biomonitoring dilakukan menggunakan biomarker S-Phenylmercapturic Acid (S-PMA) urin, sedangkan penilaian risiko dilakukan melalui penentuan Hazard Rating (HR), Exposure Rating (ER), dan Risk Rating (RR). Hasil penelitian menunjukkan bahwa SEG IPAL memiliki rerata konsentrasi benzena tertinggi pada area monitoring sebesar 0,53 ppm dan personal monitoring sebesar 0,42 ppm. Hasil biomonitoring menunjukkan rerata kadar S-PMA tertinggi ditemukan pada SEG Proses sebesar 1,08 µg/g kreatinin, diikuti SEG IPAL sebesar 0,85 µg/g kreatinin dan SEG Laboratorium sebesar 0,42 µg/g kreatinin. Seluruh hasil biomonitoring masih berada di bawah nilai Biological Exposure Index (BEI) sebesar 25 µg/g kreatinin. Penilaian CHRA menunjukkan bahwa SEG IPAL memiliki nilai ER tertinggi sebesar 5, diikuti SEG Proses sebesar 4, SEG Laboratorium sebesar 2, dan SEG Support sebesar 1. Hasil RR menunjukkan bahwa SEG IPAL dengan RR sebesar 25 dan SEG Proses dengan RR sebesar 20 termasuk kategori risiko tinggi, sedangkan SEG Laboratorium dengan RR sebesar 10 dan SEG Support dengan RR sebesar 5 termasuk kategori risiko moderat. Penelitian ini juga menunjukkan bahwa hubungan antara hasil pemantauan lingkungan kerja dan biomonitoring tidak selalu linear karena dapat dipengaruhi oleh penggunaan APD, variasi metabolisme individu, durasi pajanan, kemungkinan pajanan dermal, serta kebiasaan merokok sebagai faktor confounding. Penelitian ini menyimpulkan bahwa integrasi area monitoring, personal monitoring, biomonitoring, dan pendekatan CHRA mampu memberikan gambaran risiko pajanan benzena yang lebih komprehensif dibandingkan penggunaan satu parameter pemantauan saja. SEG IPAL dan SEG Proses merupakan kelompok prioritas utama dalam pengendalian pajanan benzena pada industri hulu minyak dan gas bumi. Pendekatan terpadu ini dapat digunakan sebagai dasar pengendalian pajanan benzena berbasis risiko untuk mendukung perlindungan kesehatan pekerja secara lebih efektif.

Benzene is a volatile aromatic hydrocarbon commonly found in the oil and gas industry and has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC). Benzene exposure among upstream oil and gas workers may cause adverse health effects, particularly hematopoietic disorders, and may increase the risk of leukemia due to chronic exposure. Risk assessment of benzene exposure is commonly based on workplace environmental monitoring; however, this approach may not fully represent the internal dose absorbed by workers. Therefore, an integrated approach combining workplace environmental monitoring and biomonitoring is needed to provide a more comprehensive risk assessment. This study aimed to analyze benzene exposure risk among upstream oil and gas workers using a Chemical Health Risk Assessment (CHRA) approach integrated with area monitoring, personal monitoring, and biomonitoring. This study used a retrospective observational design based on secondary data obtained from the company’s workplace monitoring and biomonitoring programs. The analysis was conducted among workers classified into Similar Exposure Groups (SEGs), namely Process, Wastewater Treatment Plant (WWTP/IPAL), Laboratory, and Support. Biomonitoring was performed using urinary S-Phenylmercapturic Acid (S-PMA) as a biomarker of benzene exposure, while risk assessment was conducted through the determination of Hazard Rating (HR), Exposure Rating (ER), and Risk Rating (RR). The results showed that the WWTP (IPAL) SEG had the highest mean benzene concentration in both area monitoring at 0.53 ppm and personal monitoring at 0.42 ppm. Biomonitoring results showed that the highest mean urinary S-PMA level was observed in the Process SEG at 1.08 µg/g creatinine, followed by the WWTP SEG at 0.85 µg/g creatinine and the Laboratory SEG at 0.42 µg/g creatinine. All biomonitoring results remained below the Biological Exposure Index (BEI) of 25 µg/g creatinine. The CHRA assessment showed that the WWTP SEG had the highest ER value of 5, followed by the Process SEG with an ER of 4, the Laboratory SEG with an ER of 2, and the Support SEG with an ER of 1. The RR results showed that the WWTP SEG with an RR of 25 and the Process SEG with an RR of 20 were classified as high risk, whereas the Laboratory SEG with an RR of 10 and the Support SEG with an RR of 5 were classified as moderate risk. This study also found that the relationship between workplace monitoring and biomonitoring results was not always linear, as it may be influenced by personal protective equipment use, individual metabolic variability, exposure duration, possible dermal exposure, and smoking habits as confounding factors. This study concludes that the integration of area monitoring, personal monitoring, biomonitoring, and the CHRA approach provides a more comprehensive evaluation of benzene exposure risk than relying on a single monitoring parameter alone. The WWTP and Process SEGs are the main priority groups for benzene exposure control in the upstream oil and gas industry. This integrated approach can serve as a basis for risk-based benzene exposure control to support more effective worker health protection.