Steven Hentges, Ph.D
Tuesday, February 11, 2020

If you live in Canada, there’s a good chance that you’re exposed to BPA. We know that because, late last year, Health Canada released its Fifth Report on Human Biomonitoring of Environmental Chemicals in Canada. The report, part of an ongoing program that produces biennial reports, includes extensive biomonitoring data that document exposure of the Canadian population to a range of chemicals, one of which is BPA.
 
Although this new report is focused on the Canadian population, similar biomonitoring studies have been conducted in many other countries. For example, the U.S. Centers for Disease Control and Prevention publishes its National Report on Human Exposure to Environmental Chemicals, which also includes data on exposure of the U.S. population to BPA. Biomonitoring data on BPA have also been reported in well over 100 smaller scale studies from around the world.
 
Regardless of where you live though, exposure data is only part of what you need to know. As Health Canada notes: “Finding a measurable amount of BPA in urine is an indicator of exposure to BPA and does not necessarily mean that an adverse health effect will occur.”
 
This important precaution is why there’s no need to worry. Exposure doesn’t necessarily imply there will be any health effect.
 
To better understand the potential for BPA to cause an adverse health effect, you might also want to know the source of BPA exposure, what happens to it in the body and, most importantly, is it safe at the levels to which you are exposed. For all of these questions, Health Canada doesn’t leave us hanging.
 
The source of human exposure to BPA has been extensively studied by researchers worldwide, including numerous studies from Health Canada scientists. Based on information from these studies, in particular studies on food packaging, Health Canada notes: “The primary route of exposure to BPA for the general public is through dietary intake.”
 
Where it gets interesting is what happens to BPA when it enters the body. This topic has also been extensively studied and as reported by Health Canada: “In humans, BPA is readily absorbed and undergoes extensive metabolism in the gut wall and the liver.” The importance of the key words in that sentence – extensive metabolism – is then explained: “The … metabolite is not considered to be biologically active and is rapidly excreted in urine with a half-life of less than two hours.”
 
In other words, because of the way that BPA is processed in the body, it’s not likely to be harmful. After exposure, BPA is efficiently converted to a biologically inactive metabolite, which is then quickly eliminated from the body. The biomonitoring method used by Health Canada and other researchers to measure exposure to BPA relies on this metabolic process by measuring the amount of the BPA metabolite in urine.
 
Considering all of this information, and much more, Health Canada previously conducted a science-based assessment to determine whether BPA may present a risk to human health. Its bottom line tells the story: “Health Canada has concluded that current dietary exposure to BPA through food packaging is not expected to pose a health risk to the general population, including newborns and young children.”
 
Exposure to BPA in the Canadian population and Health Canada’s conclusion on what it means is consistent with what has been reported elsewhere. Everywhere it’s been examined, exposure to BPA has been found to be very low. As to what this means, the U.S. Food and Drug Administration says it most succinctly on its website: “Is BPA safe? Yes.”