Ireland's State of the Environment Report 2024

380 Chapter 14: Environment, Health and Wellbeing AMR is a quintessential One Health issue: One Health recognises that the health of humans, animals and the environment are closely linked and interdependent. Ireland’s second One Health National Action Plan on AMR 2021-2025 (iNAP2) is the successor plan to Ireland’s first National Action Plan on AMR 2017-2020 (iNAP1) and outlines over 150 actions, both One Health-focused as well as sector-specific, to tackle the issue of AMR in Ireland (DAFM & DOH, 2021). Compared with public health and the health of food-producing animals, the health of the environment has, to date, received little attention with regard to AMR. However, the environment is a complex reservoir of antimicrobial-resistant organisms and genes that can drive AMR, and is a critical, but often overlooked, dimension of this One Health issue (see section 5). A recent research project revealed the presence of antimicrobial-resistant organisms and AMR genes of clinical concern in our aquatic environment, including those that are resistant to last-resort antimicrobials such as carbapenemase-producing Enterobacterales (Hooban et al ., 2021, 2022; Cahill et al ., 2023; Morris et al ., 2024). Discharged waste water, particularly that emanating from healthcare facilities, was found to play a significant role in dissemination of AMR in the natural aquatic environment. This persistence of resistant microbes and AMR genetic elements in our environment is an important signal of a wider problem around the use of antimicrobials, which is continuing to drive AMR. Ireland, like many other countries, does not currently have a systematic surveillance system to monitor levels of AMR in our environment. Several antimicrobial compounds are included in the Water Framework Directive (2000/60/EC) watchlist for monitoring; however, the number of substances monitored and the frequency and density of monitoring are very limited. Proposed revisions to various pieces of EU legislation, including the Urban Waste Water Treatment Directive (91/271/EEC), the Water Framework Directive, the Groundwater Directive (2006/118/EC) and the Environmental Quality Standards Directive (2008/105/EC), intend to include monitoring for AMR genes. A recent European Council recommendation (2023/C 220/01) under the 2023 Commission revision of pharmaceuticals legislation highlights that environmental monitoring of antimicrobial-resistant organisms and AMR genes in our waters, waste water and agricultural soils is ‘essential’ to understand the level of environmental contamination and the risk posed to human health (European Council, 2023). Indeed, provisional political agreement was reached in March 2024 on proposals to review the EU Urban Waste Water Treatment Directive’s higher standards of treatment and monitoring activities for micropollutants and AMR. Therefore, it seems likely that it will eventually become a legislative requirement to monitor AMR in our environment. Ireland has already made a substantial investment in research in recent years on the environmental dimension of AMR – this provides us with a wealth of evidence on which we should build. If we are to gain the requisite evidence to have a more holistic understanding of AMR and the risks it poses to human and animal health, we must step up our surveillance, not only of residues of antimicrobial compounds but also of resistant microorganisms and microbial genes coding for AMR. Algal blooms. Harmful algal blooms occurred at a number of freshwater lakes across the island of Ireland in 2023, affecting recreational bathing sites and drinking water sources and posing serious risks to aquatic life, as well as ecological, animal and human health. Toxic blue–green algae blooms are caused by cyanobacteria, which are natural inhabitants of freshwater and marine waters. These bacteria and the toxins they produce during a bloom can potentially kill livestock, wild animals and pets if ingested and can also cause harm to people who come into contact with, or swallow, the affected water. Human activities can influence the extent to which cyanobacteria can proliferate, with excess nutrients arising from agriculture and waste water systems within catchments areas, combined with climate change and weather conditions, driving the occurrence of blooms. Local authorities have responsibility for monitoring, risk assessing and analysing waters for suspect blooms. The HSE Bathing Water Working Group has developed guidance for responding to incidents of microbiological pollution in bathing waters. Restricting bathing and other water-contact activities and posting on-site warning signs are some of the recommended actions for safe practice in managing contact with blooms. Health warnings and swimming restrictions were placed across many lakes on the island of Ireland in 2023 due to harmful algal blooms. It is likely that we will continue to see changing patterns and incidences of algal blooms as a result of continued anthropogenic pressures and climate change impacts. It is essential that local authorities remain vigilant in promptly identifying harmful algal blooms and notifying the public to help safeguard public health.