NewsHealthBasildon HospitalMore than 100 maternity staff, including midwives and healthcare assistants, are taking legal action against Mid and South Essex NHS Foundation Trust after claiming nitrous oxide exposure at Basildon Hospital caused fatigue, anxiety, headaches and brain fog.Jane Kirby 13:14, 18 May 2026Updated 13:15, 18 May 2026More than 100 maternity staff are pursuing legal action against a hospital trust following exposure to nitrous oxide.Two years ago, an independent review found Mid and South Essex NHS Foundation Trust "failed to act with candour" and there was an "unacceptable delay" in its response to concerns about dangerous levels of the gas in the maternity unit at Basildon University Hospital.The review, carried out by the Good Governance Institute, concluded that midwives and other staff working in the maternity unit were "exposed to unnecessary risk or potential harm".It found that high levels of gas on wards "needed to be treated as a significant risk to health" when concerns were first raised in July 2021, yet no action was taken until October 2022. The trust stated it was addressing the review's findings.In a fresh development, staff including midwives and healthcare assistants who worked at Basildon Hospital in Essex between 2018 and 2023 are now pursuing legal action, according to the BBC. They claim to have experienced symptoms including fatigue, anxiety, headaches and "brain fog".READ MORE: Ebola outbreak is 'very concerning' as 'highly lethal' disease has no vaccine with more than 80 deadREAD MORE: Dementia care in the UK is 'stuck in a system of delay, denial and neglect', charity saysThe Press Association understands that a number of claims have already been settled, with the total value of those settlements standing at just over £89,000, encompassing damages, claimant costs and NHS legal costs. In total, 141 claims have been received by NHS Resolution.A 50:50 mixture of nitrous oxide and oxygen – commonly known as "gas and air" – is widely used to manage pain during labour and is considered by the NHS to be very safe for this purpose. According to the Health and Safety Executive, prolonged exposure to high levels in the workplace can trigger serious health complications, including neurological disorders and anaemia.Denise Townsend, acting chief nursing officer for Mid and South Essex NHS Foundation Trust, said: "We are sorry and acknowledge that we should have acted faster to address the issues.Article continues below"Since the incident we have learnt lessons and part of this is that we have improved our oversight of the monitoring of medical gases across the maternity unit at Basildon Hospital."It is understood the trust now employs scavenger equipment designed to extract nitrous oxide from the air.Several other NHS trusts have also been found to have excessively high nitrous oxide levels.Choose Daily Mirror as a 'Preferred Source' on Google News for quick access to the news you value.‌Nitrous OxideNHSPress Association Ltd.BBCHealth and Safety ExecutiveHospitalsBasildon Hospital