Oestrogens are ‘female’ hormones that can enter the aquatic environment after excretion by humans and animals, causing ‘feminisation’ of male fish. This study carried out a risk assessment for oestrogen-like endocrine disruption in the UK in the 2050s, based on likely changes to the human population, river flows and temperature. The authors found that risk is likely to increase under future conditions and recommend further research to assess whether improving sewage treatment could reduce oestrogen pollution.
Impact of climate change and population growth on a risk assessment for endocrine disruption in fish due to steroid estrogens in England and Wales, ScienceDirect, doi:10.1016/j.envpol.2014.11.017, February 2015.
In England and Wales, steroid estrogens: estrone, estradiol and ethinylestradiol have previously been identified as the main chemicals causing endocrine disruption in male fish. A national risk assessment is already available for intersex in fish arising from estrogens under current flow conditions.
This study presents, to our knowledge, the first set of national catchment-based risk assessments for steroid estrogen under future scenarios. The river flows and temperatures were perturbed using three climate change scenarios (ranging from relatively dry to wet). The effects of demographic changes on estrogen consumption and human population served by sewage treatment works were also included.
Compared to the current situation, the results indicated increased future risk:the percentage of high risk category sites, where endocrine disruption is more likely to occur, increased. These increases were mainly caused by changes in human population. This study provides regulators with valuable information to prepare for this potential increased risk.