Increased Release of Bisphenol A (BPA) and Associated Toxicity Risks

According to a recent study published in the Journal of Biomedical Materials Research Part B: Applied Biomaterials, the increased release of bisphenol A (BPA) is tied with high risks of local and systemic toxicity.

Study Aim

The main aim of this study was to perform an integrative review on the release of bisphenol A (BPA) from resin-matrix composites and potential toxic effects. A bibliographic search was performed on the PubMed platform using the following keywords:

• "Bisphenol A" OR "BPA"
• "resin composite" OR "composite resin"
• "toxicity" OR "cytotoxicity" OR "release"

Inclusion criteria involved in vitro and in vivo studies on the release and toxicity of bisphenol A (BPA).

Study Results

• The release of bisphenol A (BPA) from resin-matrix composites is due to insufficient polymerization and/or degradation of the polymeric matrix.
• Bisphenol A (BPA) is part of the organic matrix of resin-matrix composites and may be hydrolysed in human saliva, although studies report that low doses might not be detected by traditional chemical analysis.
• Studies exposing zebrafish embryos to different concentrations of Bis-GMA showed 55% mortality at 10 μM Bis-GMA while 30% mortality was recorded at 1 μM Bis-GMA.
• In patients, a bisphenol A (BPA) concentration of around 2.09 × 10⁻² μg/ml was found in the saliva after placement of lingual orthodontic retainers with resin-matrix composites.
• The bisphenol A (BPA) molecule can be swallowed and absorbed by the oral/gastrointestinal mucosa, which might result in systemic toxicity.
• The degradation of resin-matrix composites and release of bisphenol A (BPA) in the oral environment are dependent on the organic matrix content and on the polymerization method.

Thus, the researchers concluded that an increased release of bisphenol A (BPA) can lead to absorption into oral and gastrointestinal mucosa with high risks of local and systemic toxicity.

Reference

An integrative review on the toxicity of Bisphenol A (BPA) released from resin composites used in dentistry by Lígia Lopes-Rocha et al. published in the Journal of Biomedical Materials Research Part B: Applied Biomaterials.

https://doi.org/10.1002/jbm.b.34843