Two principles that I like to keep in mind when reading medical research results are useful in interpreting mainstream news reports about some of today’s hot environmental and technology topics:
1) Exposure to low levels of some useful yet potentially toxic substance may not cause health problems in the short term, but sometimes long-term exposure to the same levels can cause problems. We, as a society, learned that lesson with pesticides, no?
2) Saying that we have no evidence that something causes health problems doesn’t necessarily mean that it does not cause problems, nor that it does create problems. It may just mean that we haven’t done sufficient research on the topic to say either way.
Let me give three examples from headlines in both the medical and lay press recently.
Today, a pilot study published in the journal Environmental Health Perspectives reported that five families reduced their urinary levels of endocrine disruptors by 53%-66% simply by avoiding packaged foods for 3 days. The study measured metabolites of bisphenol A (BPA) and bis(2-ethylhexyl) phthalate (DEHP), which are chemicals used in plastic baby bottles, the linings of canned foods, and other products. The American Chemistry Council pointed out in a San Francisco Chronicle article that all the measured levels were below “government-established safe exposure levels.” But government guidelines rely on data from research, and much of the data on BPA and DEHP so far are preliminary. My colleague Doug Brunk reported a fine example of this in a recent blog post on an association between BPA exposure and childhood wheezing or asthma.
A separate study in the Journal of the American Medical Association reported last month that holding a cell phone up to your head for a 50-minute phone call increases brain activity in the area close to the phone, raising questions about the long-term safety of exposure to cell phone electromagnetic radiation. In another San Francisco Chronicle article, the International Association for the Wireless Telecommunications Industry said that research so far has “overwhelmingly indicated” that cell phones are safe. Medical and health experts in the article countered that more research is needed, but that the data are nothing to be alarmed about so far.
In California, where I live, there have been plenty of news reports lately about utilities’ plans to install “smart meters” at residences and businesses with wireless technology for real-time monitoring of electricity usage. Some opponents claim the exposure to electromagnetic emissions from the devices cause immediate health problems in a minority of susceptible people and possibly long-term problems in others, but they don’t have any solid evidence (so far, perhaps). Advocates say there’s no evidence (yet, perhaps) that smart meters cause problems in the short- or long-term.
I take a particular interest in this last topic because, in addition to being a medical news reporter, I wrote a book about plug-in electric vehicles (EVs). People sometimes ask me whether drivers are exposed to electromagnetic fields when the EV is being driven or charging. So I summarized the available research in an article for the non-profit organization Plug In America in the group’s annual resource guide, Charged Up & Ready To Roll: The Definitive Guide To Plug-in Electric Vehicles. Bottom line: There are only a limited number of small studies so far, and EVs appear to be as safe as the emission levels you’re exposed to from living in today’s typical homes. (Interpret that how you will.)
I’m sure that reports on these topics confuse and possibly alarm the general public because some of the safety issues will be unproven for the forseeable future. Fortunately, they have two other common themes. 1) There’s no need to panic. And 2) If you’re concerned, there are some simple, common-sense steps you can take.
Use your cell phone’s Speaker function or a headset rather than holding your cell phone up to your head for long periods.
Avoid sitting in an EV while it’s charging. That shouldn’t be a problem, considering that 95% of the time people plug in their EVs at night, to charge while they are in bed, sleeping. And keep in mind that the proven health benefits of getting rid of conventional car emissions (which kill thousands of people each year due to smog, respiratory problems, etc.) make EVs a better choice for the foreseeable future.
Now, stop worrying. Make your best choices by assessing the science we have so far while acknowledging the science that has yet to be done.
–Sherry Boschert (@sherryboschert on Twitter)