The fact that environmental factors induce DNA mutations that may lead to disease is well-established and will have tremendous benefits when incorporated into various environmental safety and health assessments. Environmental factors such as dietary intake, drugs, stress, or exposure to toxins, can cause epigenetic changes by possibly altering how transcription factors bind to DNA or changing the structure of the histones that DNA wraps around. These structural changes can affect gene activity or gene expression. A number of environmental factors have been investigated for their effect on epigenetic changes including phthalates, toxic metals, smoking, air pollution, jet fuel, environmental stress, and a high fat diet. Effects on epigenetic mechanisms, DNA methylation patterns, histone modifications, miRNA expression have been documented as a result. The table below (Marczylo et al, 2016 and Society of Toxicology, 2018) summarizes a few of the studies that have been done for putative environmentally-induced epigenetic toxicity in humans or rat/mouse.
In the future, incorporating epigenetic evaluation into toxicity tests can increase the safety of both food and environmental substances.
|Toxin/exposure||Species/stage of exposure/effect||Phenotype||Epigenetic change||Reference(s)|
|Air pollution||Human/childhood/childhood||Asthma||Epigenetic mechanisms||Somineni et al. (2016)|
|BPA||Human/in utero/childhood||Behavior||DNA methylation||Kundakovic (2015)|
|Formaldehyde||Human/lifetime/adult||Alzheimer’s||Epigenetic mechanisms and DNA methylation||Tong et al. (2015)|
|Methylmercury||Rodent/in utero/adult||Behavior||Histone modifications and DNA methylation||Onishchenko (2008)|
|Arsenic||Human/lifetime/adult||Skin disorder||DNA methylation||Paul et al. (2014)|
|Nickel||Human/lifetime/adult||NSCLC survival||miRNA||Chiou et al. (2015)|
|Polycyclic aromatic hydrocarbons||Human/adult/adult||Chromosome aberrations - PBL||DNA methylation||Yang et al. (2012)|
|Various phthalates||Rodent/in utero/adult||Decreased testosterone/gonadal||DNA methylation and histone modifications||Kilcoyne et al. (2014) Martinez-Arguelles et al. (2009), Papoutsis et al. (2015), Takeda et al. (2012), Yoshioka et al. (2011)|
|Smoking||Human/Lifetime/adult||COPD and tumor||Epigenetic mechanisms, DNA methylation, miRNA||Lin (2010), Ostrow (2013) Shenker (2013), Xie et al. (2014)|
|Alcohol||Rodent/lifetime and in utero||Nuerological, cardiac, behavior, stem cell||Histone modification and miRNA||Ignacio et al. (2014), Middleton et al. (2012), Leu et al. (2014), Pascual et al. (2011), Peng et al. (2015)|
|High fat diet||Rodent/in utero/adult||Diet preference||DNA methylation and miRNAs||Baselga-Escudero (2015), Carlin et al. (2013), Vucetic et al. (2010)|
|Under-nourishment||Rodent/adult/adult||Hepatic||miRNAs||Tryndyak et al. (2016)|