A newly published study appearing on August 28, 2013 in the peer-reviewed journal PLOS ONE sheds light on previous findings of hormone activity in bottled waters (Wagner and Oehlmann 2009, Wagner et al. 2013). Researchers from Germany purchased 18 samples of PET, glass or carton bottled waters from retail outlets and tested them for their antiestrogenic and antiandrogenic activities. According to the article, 16 of 18 samples were antiandrogenic, and 13 were antiestrogenic. In these samples the substance di(2-ethylhexyl) fumarate (DEHF; CAS 141-02-6) was detected. DEHF is authorized as indirect food additive in the US and permitted for use as monomer in adhesives and coatings, in paperboard and as additive in silicones. DEHF may also be an impurity of the surfactant dioctyl sodium sulfosuccinate (DEHSS; CAS 577-11-7), however this substance is not authorized for food contact materials in the US or Europe.
The study’s authors point out that not all antiestrogenic effect could be explained by DEHF. Furthermore, DEHF cannot be responsible for the observed antiandrogenicity. According to the authors, this demonstrates that additional, so far unknown inhibitors of hormone receptors must be present in bottled water.
They also report that other structurally related substances, in particular dioctyl maleate (DOM; CAS 2915-52-9) and dioctyl fumarate (DOF; CAS 2997-85-5) are hormonally active. DOM is authorized as indirect food additive in the US. According to a recent study by The PEW Charitable Trusts, DEHF and DOM are among those 80% of direct and indirect food additives without sufficient toxicological data (Neltner et al. 2013).
It is noteworthy that compounds are ubiquitously present in bottled waters lacking relevant toxicological data, and hence no conclusions on their potential risks to humans are possible. Further studies are needed to fully understand what substances are present in commercial bottled waters and importantly, to elucidate their sources. The present study does not permit any conclusions as to where the antiestrogenic DEHF originated from: it may have been present in the water due to source contamination, or could have migrated either from the storage or filling equipment. Another possibility is that DEHF leached from the packaging material after filling. While there was no association between food contact material type and hormonal activity, the only two samples free from hormonal activity in this study were packaged in glass.
Wagner and colleagues stress the importance of these findings, as DEHF, DOM, DOF and structural isomers have so far been neglected by regulators and researchers. However, they seem to be present in widely consumed foodstuffs, which should motivate further research into their toxicological hazards, and stimulate studies aimed at improving understanding of sources and exposure levels.
Wagner, M., et al. (2013). “Identification of Putative Steroid Receptor Antagonists in Bottled Water: Combining Bioassays and High-Resolution Mass Spectrometry.” PLOS ONE 8(8): e72472.
Wagner, M. and J. Oehlmann (2009). “Endocrine disruptors in bottled mineral water: total estrogenic burden and migration from plastic bottles.” Environ Sci Pollut Res Int: 278-286.
Neltner, T. G., et al. (2013). “Data Gaps in Toxicity Testing of Chemicals Allowed in Food in the United States.” Reproductive Toxicology (online August 13, 2013).