Chronic oiling in North Sea is “grossly underestimated”

The steady release of oil into the sea threatens marine life, accumulating in animals and acting as carcinogens as well as entering the human food system

A new report from international ocean conservation organisation, Oceana in the UK claims that the true extent of frequent, small-scale ‘chronic oiling’ in the North Sea has been “grossly underestimated” due to a combination of the oil industry’s failure to provide data and an opaque and misleading reporting system.

Oil companies must report both accidental oil spills and intentional discharges of so-called ‘produced water’ — a byproduct containing oil and other toxic chemicals — which can be released under permit. However, breaches of these permits, despite representing considerable oil contamination, have typically been excluded from external analysis and scrutiny.

As a result, levels of oil pollution have typically been significantly underestimated. When ‘permit breaches’ are added to ‘accidental spills’, the total volume of oil spilt into UK waters since 2014 increases by 43%, and more than doubles the volume between 2021-2024. 

Findings from Sea Slick: The true scale and impact of chronic oil pollution in UK seas also show that oil corporations are failing to accurately report, as nearly a third (32%) of the reports of permit breaches for ‘produced water’ failed to include the volume of oil discharged – meaning the true level of pollution is likely to be even higher.

Dr Rosie Williams, Postdoctoral Researcher at the Zoological Society of London (ZSL) says: “A growing body of research now recognises that the steady release of oil and other toxins into marine environments poses a huge threat to marine life.

“Substances such as PAHs and heavy metals can accumulate in animals and act as carcinogens and negatively impact the immune and reproductive systems. This bioaccumulation of chemicals is also a major concern from a human health perspective, as they enter our own food system.”

Williams added that the government needs to do more to hold oil companies to account. “The underreporting from the industry on what toxins are being released into our ocean is an issue that must be urgently addressed.”

Poor enforcement and regulation exacerbate the problem. Since 2014, less than 2% of all oil discharge permit applications have been rejected. Of the permit breaches reported between January 2011 and May 2024, less than 1% were investigated. 

Spills are self-reported by oil companies, and in 2023, the Offshore Petroleum Regulator for Environment and Decommissioning (OPRED) only inspected 15% of oil and gas infrastructure, down from 25% in 2022.

“Our investigation reveals a shambles of opaque and incomplete reporting that is concealing the true scale of the toxic oil pollution causing devastation for UK seas...”

The Department for Energy Security and Net Zero (DESNZ) states that applications for oil discharge permits are ‘subject to scrutiny by inspectors where the operator must demonstrate that Best Available Techniques are applied to prevent or minimise discharges to the marine environment’. 

A DESNZ spokesperson said, “We have a comprehensive framework of environmental protection measures for offshore oil and gas activities.

“Every oil spill, and discharge non-conformance is investigated by OPRED proportionately, which can take enforcement action against operators if needed, including the use of fines or referral for criminal prosecution. We review and update guidance as required.”

Hugo Tagholm, Executive Director of Oceana in the UK countered: “Our investigation reveals a shambles of opaque and incomplete reporting that is concealing the true scale of the toxic oil pollution causing devastation for UK seas and marine wildlife.

“The oil industry has so far been allowed to mark its own homework on this with barely any oversight. The government can and must now chart a new course, holding the industry accountable and ensuring that our seas get the protection they deserve.”