Question to the Department for Environment, Food and Rural Affairs:

To ask Her Majesty’s Government what assessment they have made of the possible role of the contraceptive chemical E22, which is resistant to water purification techniques, in the increase in number of freshwater and coastal water fish bearing both male and female sexual organs.

In the UK, environmental regulators, scientific experts and the water industry have been researching the link between the synthetic steroid, 17α-ethinyloestradiol (EE2, used in human oral contraception) and fish populations to understand the role of endocrine disrupting chemicals on the reproductive physiology of fish. Most work has focused on EE2 which has been measured in some of our rivers and downstream of sewage treatment works (STWs); this matches findings in other countries.

Based on scientific evidence from the UK and in Europe, there is reasonable certainty that very low concentrations of EE2 can cause feminisation (intersex condition) in male fish. The incidence of intersex seems to relate to the size of the STWs and the dilution ability of receiving waters. In the UK, fish inhabit comparatively small-sized rivers where limited dilution of EE2 occurs. Conventional STWs can remove EE2 from sewage, but not to the very low levels of less than one nanogramme per litre (ng/L) where no endocrine disrupting effects are predicted. In some cases the impact on fish populations remains unclear, and some affected populations appear to be self-sustaining.

In 2014, EE2 was included on the European Commission’s ‘watch list’ under the Water Framework Directive to gather information on its occurrence in surface waters across the European Union. Data will be reported by the UK and other Member States, and reviewed by the Commission throughout 2017 to assess whether this pharmaceutical is to be prioritised for monitoring and control and is to be included in future versions of the Directive.