Epigenetic effects of environmental chemicals bisphenol A and phthalates.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing preclinical mechanistic cell and animal experiments without human clinical data.
PubMed 22949852 · doi:10.3390/ijms130810143
What was done
This narrative review summarizes findings from in vitro cell lines (human breast cancer MCF7 cells, placental cells) and in vivo rodent models (mice and rats) evaluating the epigenetic impacts—DNA methylation, histone modifications, and microRNA expression—of exposure to bisphenol A (BPA) and phthalates (such as BBP and DEHP).
What was found
The abstract reports qualitative mechanistic directions without numerical metrics: - BPA exposure decreased CpG methylation upstream of the Agouti gene in viable yellow mice; this hypomethylation was prevented by maternal supplementation with folic acid or genistein. - BPA induced trimethylation of histone H3 at lysine 27 via EZH2 in mice and a human breast cancer cell line. - BPA altered microRNA expression in human placental cell lines, specifically inducing miR-146a. - Phthalate BBP induced demethylation of ESR1 promoter-associated CpG islands in MCF7 cells, altering ESR1 mRNA expression. - Maternal DEHP exposure increased DNA methylation and DNA methyltransferase expression in mouse testis. - Selected epigenetic effects of BPA and phthalates in female rats were transgenerational.
Why it matters
The paper outlines mechanistic pathways illustrating how early-life exposure to plasticizers and endocrine-disrupting chemicals can alter gene expression through epigenetic marks, potentially influencing disease vulnerability across generations.
Limits
All findings described in the abstract derive from animal and in vitro cell culture models rather than human clinical or epidemiological studies. No sample sizes, quantitative effect estimates, or exposure doses are reported in the abstract. As a narrative review, it lacks a systematic search methodology or risk-of-bias assessment.
Cited by
- supports Specific nutrients such as vitamin B9 (folic acid), omega-3 fatty acids, quercetin, and vitamin C offset epigenomic alterations caused by environmental chemicals.