The number of deaths related to nitazenes have ‘likely been underestimated by up to a third’, according to researchers at King’s College London.
The National Crime Agency (NCA) reported just over 330 deaths linked to nitazenes in 2024. However the King’s College researchers believe that the substances’ stability in postmortem blood samples mean they are likely being missed in toxicology tests. After concerns were raised by toxicologists, the research team used anesthetised rats to find that, on average, just 14 per cent of nitazene present at the time of overdose was still present when tested under ‘real world’ pathology and toxicology sample handling conditions.
The team then used modelling to show a 33 per cent excess in drug-related deaths in Birmingham in 2023, based on data from King’s College’s National Programme on Substance Use Mortality (NPSUM). The researchers believe that ‘a credible explanation for at least some of these excess deaths may be due to the non-detection of nitazene that degraded prior to toxicology testing being performed’, as it typically takes around a month for blood samples to be analysed by toxicologists.
Last year King’s College researchers concluded that opioid-related deaths in England and Wales between 2011 and 2022 were more than 50 per cent higher than those recorded in official ONS statistics, as while ONS based its figures on the information provided by coroners on death certificates it did not have access to post-mortem reports or toxicology results. This meant that if death certificate were missing information – such as when deaths are the result of polydrug use and recorded with ‘ambiguous terms such as “multidrug overdose”’ – ONS is unable to ‘determine the individual substances involved’.
Even according to official ONS statistics, deaths involving a nitazene almost quadrupled between 2023 and 2024, while last week Public Health Scotland warned anyone buying street drugs to assume that they were contaminated with other substances.
The nitazene study – which is published the journal Clinical Toxicology – also included researchers from University College London, University of Bristol, London School of Hygiene & Tropical Medicine, University of Glasgow, University Hospitals Birmingham NHS Foundation Trust, and King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia.
The research showed that the harm caused by nitazenes was ‘likely being significantly underestimated’, said senior lecturer in pharmacology and toxicology at King’s College, Dr Caroline Copeland. ‘Because these drugs degrade in post-mortem blood, we may be missing up to a third of the deaths they are involved in, meaning public health responses are being designed and funded for only two-thirds of the real problem.’
Behind the undercount were ‘people dying suddenly from extremely potent opioids, families left without answers, and communities facing a growing but largely hidden toll’, she continued. ‘We’re trying to tackle a crisis using incomplete data. When we don’t measure a problem properly, we don’t design the right interventions – and the inevitable consequence is that preventable deaths will continue. Understanding how nitazenes degrade, and what they degrade into, is critical. If we can identify these breakdown products and where degradation is occurring, we will be able to detect deaths more accurately and respond more effectively. Better science leads to better surveillance, and better surveillance will save lives.’
‘The extreme potency of nitazenes has clearly contributed to rising overdose and death rates amongst people who use drugs,’ added Forward Trust CEO Mike Trace. ‘This research shows the official numbers are probably underestimates, supporting our calls for the government to be braver in rolling out drug testing and overdose prevention measures to save lives. With over 17,000 people per year across the UK dying from drug or alcohol related causes, we cannot afford to be hesitant in providing life-saving health services to people taking illegal drugs.’
Is nitazene-related mortality underestimated? Findings from an in vivo and ex vivo rat study and pharmacoepidemiological analysis of coroner-reported deaths available in Clinical Toxicology journal here