Every day we are inundated
with various social media posts and news sources telling us about what does or
does not work, that some things may be harmful, or that a product is not safe
because it contains a chemical that causes cancer or other adverse health
effects in animals.

You may wonder if you should start avoiding certain products in hopes of
keeping you and your family safe.. It's confusing for other scientists as well,
and you may not be sure how or where to start when trying to make informed  decisions, so here are a few tips that help me
sort it out:

1. Understand Exposure and Risk

We are exposed to numerous
activities each day that have the potential to be harmful.  You may read
something suggesting that a chemical associated with cancer is also found in
consumer products, fruits, or beverages and wonder if it’s really causing you
harm. All things can be a hazard because hazard simply means the ability of
some thing or activity to cause harm. The real question is “What is my risk,
and what is the likelihood that I will be harmed by normal use or consumption
of this product?” 

 Risk is defined as the probability that harm will actually occur and that is
based on how you interact with a product or chemical or thing. While a lion
attack poses a high hazard of injury in the wild, if you live in Texas, where
the presence of encountering a lion is generally in a zoo, your risk of an
attack is low. It's the same with many chemicals. Chemistry is a basic
component of life, and we are naturally exposed to a broad range of chemicals
by nature and because our bodies produce chemicals through normal human
functions.

For example, formaldehyde is
produced by our bodies as part of the natural processes in our cells but it is
also an essential building block in the production of hundreds of items, like
automobile components, cabinetry, flooring and medical devices. How do some
reports link it to cancer when it is natural? They could, for example, be using
high doses in animals that are unlikely to be encountered by consumers or  be using some form of  statistical correlation. Recently, the U.S.
Environmental Protection Agency (EPA) initiated a risk evaluation of
formaldehyde with the purpose of determining whether formaldehyde presents real
risks to human health or the environment at realistic levels of exposure. 
So should you be concerned?

EPA evaluates chemicals
regularly, in case there might be new evidence, so that is not cause for worry.
When it assesses possible adverse health effects, it will consider  potential risk from formaldehyde exposure in
the air, the normal levels of formaldehyde naturally found in the human body,
and potential risk. It’s important to remember that risk depends on a variety
of factors, including how much a person is exposed, how they are exposed, and
for how long. 

2. Rely on Scientific Experts and Data

With so much noise in
today’s digital landscape, it may be hard to determine what you should pay
attention to and who would be the best source of information. When it comes to human health risk, scientific
experts are your best allies. Using the formaldehyde example again, it's
comforting that it is one of the most extensively studied chemicals, with
decades of scientific research focused on understanding the potential for
development of adverse health effects, including cancer. 

Researchers have studied how formaldehyde enters into and moves throughout the
body and multiple international and federal agencies have evaluated the science
around formaldehyde to establish guidelines at safe levels. The World Health
Organization developed indoor air quality guidelines that were conservative and
protective. In the United States, formaldehyde is also regulated and EPA even
established standards for formaldehyde that might come from composite wood
products. 

Additionally, federal agencies like
the EPA, the Consumer Product Safety Commission and the Centers for Disease
Control and Prevention employ a cadre of scientific experts in epidemiology,
toxicology and exposure science. These scientists focus on evaluating
information about chemicals and their findings and conclusions are made
available on public websites. So when you see a story regarding a product or
chemical, some important questions to ask are: what is the source of this information;
is the information generated by a scientists with expertise in the field; and
has the information been peer reviewed by other members of the scientific
community.

3. Weigh
the Science

When making a decision, big or
small, it is important to evaluate all the information to make an informed
decision. For example, when you are deciding on the best pizza restaurant to
order takeout from, you "weigh" information you might know about
quality of the food, cost, or past experiences. Similarly, when scientists see
a claim about a chemical and its potential for harm, we weigh the quality of
the data, specific strengths and weaknesses of the information, and any
inconsistencies.

In the formaldehyde example, there
are thousands of peer-reviewed scientific articles and dozens of chemical
reviews already conducted by federal and international agencies spanning
decades. To determine risk using so many studies, we conduct a systematic
review because it uses a clearly defined approach to identify relevant
scientific information, evaluates the quality of the data, and weighs the
information to reach conclusions about human health risk.  

A few questions to consider when we weigh the
science, and you can also use when reading claims in media include “Is all the
evidence reaching the same conclusions about the chemical or is this just one
paper?” “Is the evidence discordant from what other studies have found?” “What
does the scientific community or relevant regulatory agencies conclusions say?”
and finally, “Is the data actually addressing the question I am trying to
answer?” 

There are also tools that can aid
you in spotting “bad” science that include, for example, assessing if there are
issues with the quality of the data or if the results have been misinterpreted. 

The above tips highlight why science-based decision making to determine human
health risks is so important. If hazard information is taken out of context and
not appropriately used with an understanding of the available use and exposure
information for a chemical, the conclusions can be mischaracterized and
misunderstood. If you want a more detailed list, you can go to “A
Rough Guide to Spotting Bad Science.”