- Nearly 2.4 million deaths every year are attributable to air pollution.
- PM2.5 pollution is one of the most prominent air pollutants because they deposit in the respiratory tract resulting in both lung and systemic inflammation and stress.
- B-vitamin supplements significantly increased the median plasma concentrations of folic acid, vitamin B6, and vitamin B12.
B vitamins may play a critical role in reducing the impact of air pollution on the epigenome. It is a multitude of chemical compounds that can tell the genome what to do. A new study is the first to give a detailed course of research for developing interventions that prevent or minimize the adverse effects of air pollution on potential automatic markers.
The study, conducted with colleagues at Harvard's T. H. Chan School of Public Health, in Sweden, China, Singapore, Mexico and Canada, reveals how individual-level prevention may be used to control the potential pathways underlying adverse effects of the particles PM2.5, particles with an aerodynamic diameter of <2.5 micro meter. These findings could have a significant public health benefit in regions of the world with frequent PM2.5 peaks.
"The molecular foundations of air pollution's health effects are not fully understood, and the lack of individual-level preventative options represented a critical knowledge gap," said Andrea Baccarelli, MD, PhD, professor and chair of Environmental Health Sciences at the Mailman School.
While there has been substantial lowering of ambient PM2.5 achieved through large-scale emissions control policies over the past few decades, exposure peaks with adverse health consequences are still frequently recorded.
"The health effects of air pollution and how it plays a role in one's health raise many complex issues," said Jia Zhong, principal investigator, and postdoctoral research officer in the Department of Environmental Health Sciences. "Until we can attack the problem on an individual level we are a long way from fully tackling its challenges for the public's health."
"Our study launches a line of research for developing preventive interventions to minimize the adverse effects of air pollution on potential mechanistic markers. Because of the central role of epigenetic modifications in mediating environmental effects, our findings could very possibly be extended to other toxicants and environmental diseases."
B Vitamin Supplementation
Healthy volunteers aged 18 - 60 years who don't smoke and who were not on any medicines or vitamin supplements were recruited for the study.
The researchers administered one placebo or B-vitamin supplement (2.5 mg of folic acid, 50 mg of vitamin B6, and 1 mg of vitamin B12) daily to each adult recruited for the trial.
Plasma B vitamin measurements taken before and after placebo and supplementation showed that B-vitamin supplements significantly increased the median plasma concentrations of folic acid, vitamin B6, and vitamin B12.
Ambient particles were drawn from an inlet next to a heavily trafficked street in downtown Toronto with more than 1000 vehicles passing through each hour. Particles were delivered via an "oxygen type" face mask. Blood samples were collected and measured using the Infinium Human Methylation 450K BeadChip.
"While emission control and regulation is the backbone of prevention, high exposures are, unfortunately, the rule still in many mega cities throughout the world. As individuals, we have limited options to protect ourselves against air pollution. Future studies, especially in heavily polluted areas, are urgently needed to validate our findings and ultimately develop preventive interventions using B vitamins to contain the health effects of air pollution," said Dr. Baccarelli.
- Andrea Baccarelli et al., Taking B vitamins may reduce epigenetic effects of air pollution, Proceedings of the National Academy of Sciences (2017).