Bisphenol F

Bisphenol F (4,4’-dihydroxydiphenyl-methane, BPF) is a small aromatic organic compound with the chemical formula (HOC6H4)2CH2. It is related to bisphenol A through its basic structure, as both belong to the category of molecules known as bisphenols, which feature two phenol groups connected via linking molecules. In BPF, the two aromatic rings are linked by a methylene connecting group.

Uses

BPF is used in the manufacturing of plastics and epoxy resins. It is used in the industry as a way of increasing the thickness and durability of materials.^[1] Its use in this way is important in the production of tank and pipe linings, industrial floors, road and bridge deck toppings, structural adhesives, grouts, coatings and electrical varnishes.^[2] BPF is also utilized in liners, lacquers, adhesives, plastics, and the coating of drinks and food cans.^[1] Another use for BPF is in dental materials, where it can be found in restorative materials, liners, adhesives, oral prosthetic devices and tissue substitutes.^[1]

Biological effects

Studies into the metabolism and excretion processes for the molecule have shown that the compound undergoes two primary phase II biotransformations to form the corresponding glucuronide and sulfate.^[3][4][5] Different cell types have a bias towards which metabolite gets produced, with the human hepatoma cell line primarily metabolizing to the corresponding sulfate, and hepatocytes metabolizing to both the glucuronide and the sulfate compounds.^[5] Additionally, phase I metabolism produces various hydroxylated metabolites of BPF, with the main metabolites being meta-hydroxylated BPF, ortho-hydroxylated BPF and dihydroxybenzophenone (DHB).^[3][4] These metabolic pathways are P450 dependent.^[4]

According to a study done on rats, the primary route of excretion of BPF and its metabolites is through the urine, with 43-54% of the dose being excreted in this manner.^[2] In addition, 15-20% was excreted through the feces. The remainder of the administered dose was found throughout the rat, with it being found primarily in the digestive tract lumen and the liver. In pregnant rats, the BPF was also found in the uterus, placenta, amniotic fluid and fetuses, indicating that BPF is able to be absorbed into the reproductive tract and pass through the placental barrier in pregnant rats.^[2]

Environmental contamination

BPF has been shown to be present in the environment and as a food contaminant.^[3][6] This results in a low level, chronic exposure for humans. Due to this chronic exposure and the estrogenic effects that BPA has been shown to have, studies on BPF have occurred and are still occurring, to assess the effects that BPF has on living organisms.

The cytotoxicity and genotoxicity of BPF and some of its metabolites has been characterized, with BPF exhibiting an intermediate cytotoxicity.^[3] BPF was not found to produce any genetic mutation when tested via an Ames test.^[6] However, when human cell lines were tested and a Comet assay was conducted, BPF caused DNA fragmentation when introduced to the cells at non-cytotoxic concentrations.^[6] In addition, another study found BPF to be genotoxic when introduced to Hep G2 cells.^[3]

A literature review of in vivo studies of BPF found that four out of five studies yielded results that BPF is estrogenic, androgenic and thyroidogenic.^[1] In addition, one study done in rats found the greatest effect of BPF to be liver toxicity.^[7] In vitro studies of BPF showed effects of cytotoxicity, cellular dysfunction, DNA damage and chromosomal aberrations.^[1]

References