Many bisphenol A alternatives may be endocrine disruptive

New UBA study: only one tested substitute shows no evidence of hormone-mimicking effects

Reagenzkolben mit FlüssigkeitClick to enlarge
Bisphenol A is one of the world's most prolifically produced chemicals.
Source: Vasily Merkushev / Fotolia.com

A research project by the German Environment Agency (UBA) tested 44 potential substitutes for bisphenol A (BPA) for a number of different applications and products. The result: 43 of these substances are not recommended for use, either because they have a hormone-mimicking effect or a lack of data has not conclusively disproved evidence of such an effect. BPA can be found in tins or adhesives. Up until January 2020, BPA was also used as a colour developer for sales slips made from heat-sensitive paper. The UBA recommends continued disposal of these sales slips together with residual waste since there is currently no final evaluation of alternative colour developers such as bisphenol S (BPS). These substances can be spread through waste paper collection and then re-enter the consumer cycle or environment via recycled products such as toilet paper.

The particular aim of the research project was to test possible alternative substances for use in BPA applications (e.g. as a colour developer in heat-sensitive papers, as a stabiliser in textile dyes or in the lining of water pipes) for which the UBA associates a high level of discharge into the environment. Only one substance – Pergafast 201 – tested negative in all of the in vitro screening tests which might indicate an endocrine-like effect. 33 of the remaining 43 substances demonstrated signs of potential influence on the endocrine system, and the gaps in the data collected during the project in in vitro tests or literature reviews of the 10 other could not be closed. Other environmentally problematic properties such as persistence in the environment or bioaccumulation in organisms was not the object of testing. The results of the tests will be integrated into the EU REACH process to regulate the bisphenol compounds. The Member States and European Chemicals Agency (ECHA) will base discussions on these and other data to take a decision on any further data requirements of producers on substances in this group in order to draw conclusions about their suspected endocrine disruptive effect on man and the environment. If the suspicion is confirmed, a limitation on problematic substances could be introduced for use in specific applications to protect people and the environment against exposure to these endocrine disruptive substances.

The colour developer used up to now in sales register slips made from heat-sensitive paper has been bisphenol A and bisphenol S. As of 2 January 2020, thermal paper with BPA concentrations equal to or more than 0.02% by weight will be banned in the EU. There is no similar ban on substitute substances. Not all producers of thermal papers have switched to bisphenol- and phenol-free products, which is why, as a precautionary measure, these papers should continue to be disposed of together with residual waste. The German Environment Agency sees the trend towards thermal papers free of colour developers as well as the digital storage of sales receipts instead of their printout as positive. Further information about the sales slip obligation from an environmental point of view and possible alternatives to a printed receipt is available from the German Environment Agency; see Fragen und Antworten zur Bonpflicht (German). The FAQs on bisphenol A in consumer products by the Federal Institute for Risk Assessment ( BfR ) provides information about health risks, risk assessments and limit values.

Bisphenol A was one of the first synthetic substances able to mimic the effects of the female sex hormone estrogen. But because much more potent synthetic estrogens are available, bisphenol A became used as an industrial chemical and is now present in many everyday products. The substance is used among others as a curing agent for polycarbonates in plastics production and for the production of epoxy resins. BPA has an endocrine disruptive effect on people and the environment and is classified as reprotoxic, that is, it reduces fertility in man and animals. It is also suspected to favour the development of certain tumours.

BPA has now been identified throughout the EU as a Substance of Very High Concern (SVHC) under REACH due to its endocrine disruptive effects on human health, the environment and its reprotoxic effect. The present research project therefore tested substances whose similar chemical and technical properties are able to substitute BPA for their hormone-damaging effects. BPS is currently considered as the most viable substitute for BPA, but it is also suspected to have endocrine disruptive effects in humans and the environment. There are considerable gaps in the data for an evaluation of many other substitutes, which commercial companies are only in part closing to fulfil the data requirements pursuant to the REACH Directive.