For example, it is estimated that about 300 g and 40 kg of synthetic and natural oestrogen, respectively, are discharged into the sea each year from the city of St. Petersburg. Antibiotics also enter the waterways via many different routes. However, it is as yet unknown how the marine biological community reacts to antibiotics.
Certain chemicals can also affect hormone function
Besides medicinal products and hormones, chemicals produced for other purposes can also have hormonal effects. Such compounds include, among others, perfluorinated compounds (PFOS, PFOA), as well as polybrominated diphenyl ethers (PBDEs).
However, information on the properties of many existing and some new chemicals remains incomplete.
TBT has caused the extinction of entire populations of aquatic snails
The use of organic tin compounds, e.g. tributyltin (TBT), as anti-fouling marine primer paints for ship hulls is banned worldwide. However, TBT and its breakdown products will continue to circulate for a long time in the food web.
TBT acts as a very potent androgen or male hormone. For example, in aquatic snails, it causes the development of male genitalia in females, resulting in female sterilisation. In the worst-case scenario, entire populations of aquatic snails have died out in TBT-contaminated areas.
Authorities have become aware of the problems of hormone disruptors
In the European Union, a list has been made of a group of chemicals that are suspected of interfering with animal and human hormone functions. The Organisation for Economic Co-operation and Development (OECD), for its part, has drafted guidelines for testing and evaluating these hormone disruptors.
In Finland, attention is also focussed on hormone disruptors through the Finnish National Programme on Hazardous Chemicals. The aim is to reduce the use of such chemicals. In addition, their emissions, occurrence, as well as health and environmental impacts will be studied.