International Agency for Research on Cancer (IARC) review has shown proof of increased risk of cancer among residents and staff who live near petroleum facilities.
The IARC is the cancer research arm of the World Health Organization (WHO).
For the review, scientists incorporated a recent systematic review and meta-analysis including studies published up to 2012.
Results from the study are based on data from 36 cohort studies which assessed the meta-relative risk of 11 cancers among petroleum refinery workers.
Scientists in the Environment and Lifestyle Epidemiology Branch of the IARC conducted the new review published online on April 20, 2021.
Lead authors in the review are listed as Professors Onyije FM, Hosseini, Togawa, Schüz and Olsson.
The study is entitled : Cancer incidence and mortality among petroleum industry workers and residents living in oil producing communities: a systematic review and meta-analysis.
It is published in the International Journal of Environmental Research and Public Health.
Study findings indicate that petroleum industry workers and residents living near petroleum facilities are at an increased risk of developing several types of cancer.
Researchers carried out a systematic review and meta-analysis of 41 cohort studies, 14 case–control studies, and two cross-sectional studies before publishing the results.
This study will be another important plank in the growing body of evidence of the adverse effects living with air pollution that is a by-product of petroleum extraction and refining.
It paints a disturbing picture of workers and residents living near petroleum facilities as being at greater risk of several cancers.
The review also recognized that working in petroleum industries is associated with an increased risk of multiple myeloma, cancers of the prostate and urinary bladder, mesothelioma and skin melanoma.
Jobs in the sector are also associated with a decreased risk of cancers of the rectum, pancreas, oesophagus, colon, and stomach.
Review results indicated a higher cancer risk or meta-relative risks of acute lymphoid leukemia, mesothelioma and malignant skin melanoma.
Data reviewed did not show increased risks of lung and kidney cancers, non-Hodgkin’s lymphoma (NHL), chronic lymphocytic leukemia, total leukemia, acute non-lymphocytic leukemia, , chronic myeloid leukemia, and multiple myeloma.
Despite the fact that the review only focused on hematological disease or malignancy, the most recent review of people living near petroleum industry locations has also found higher risks for developing leukemia.
Stratified analysis of available data showed that working on off-shore petroleum sites was associated with an increased risk of lung cancer and leukaemia.
An increased risk of childhood leukaemia was noted in closeness or residential proximity to petroleum facilities.
Many of the associations, however, appear to be due
to factors other than those directly emerging from petroleum production.
This applies to asbestos for mesothelioma, which is a rare cancer, so that the number of cases directly attributable to air pollution is not significant enough to raise concern.
The review has also spotlighted the need for targeted studies in areas of high petroleum production that could report higher levels of exposure to petroleum.
One possible area of study that could bring interesting results is a comprehensive, large cross sectional study in Africa, the Middle East, and Asia, to harmonize study protocols and exposure assessments.
One drawback of the review is that it did not include studies on petroleum workers and residents living in oil producing communities in Africa.
This is despite the fact that Nigeria and Angola are among some of the top global oil producers.
In the Niger Delta region of Nigeria, for instance, there have been frequent oil spills that have polluted the ground water in addition to contaminating the landscape and polluting water in the soil.
The spills have also resulted in constant emission of hydrocarbons and other toxic chemicals in the petroleum production sites .
Residential houses in such areas are often built next to petroleum oil wells with pipelines running across the settlements.
In a distressing trend noted by previous research, residents in such areas sometimes use crude oil for dermal care or orally administer it to children as treatment for childhood convulsions among other illnesses.
In the Ogoniland, Niger Delta region of Nigeria, the United Nations Environment Programme (UNEP) reported that benzene level was 900 times above recommended WHO guidelines in some spots , as a result of petroleum pollution.
Significant oil pollution levels have similarly been reported in other petroleum producing regions of the world including the Russian Federation and the Middle East.
To boost efforts to expand available knowledge on the link between petroleum exposure and cancer, such a study should cover the regions.
Kenya has already begun oil drilling and exploration operations in Turkana County with possible offshore sites lined up along the country’s Atlantic coastline.
It could also gain vital insights and crucial data from participating in a national or continental study on risk of the cancer among residents and staff in petroleum production sites.
To assure on quality and secure multisectoral support, the effort could be handled by an international team of scientists drawn from the public and private sector in the participating countries.
After carrying out a methodological quality of studies evaluated on petroleum workers, the review recorded an average score of 74 percent for the cohort studies and 84 percent for case control studies.
On average, residents living near petroleum facilities registered an average score of 41 percent for cohort studies,
With 61 percent seen in cross-sectional studies, with 70 percent for case-control studies.
Research authors have stated that further studies are needed to describe the different ways people can get exposed to exposure of petroleum and its closest by-products or derivatives like benzene.
This is necessary, says the scientists, to identify what affects or shapes the various cancer risks.
