Exhausted and confused by an unending stream of articles and social media posts claiming your food is full of toxins?
This simple Android application offers some perspective by comparing consumer ingredients based on their median lethal oral dose on a scale of layperson-friendly reference points. This is not a buying guide -- no advice is given and no in-depth analysis is done on any of the ingredients -- it's simply meant to be a reality check. Although toxicity is complicated and involves more than acute effects caused by short-term exposure, it is important to understand the crucial role that dosage plays in evaluating potentially harmful material.
Popular culture has not kept up with two ideas that are important in understanding chemicals in general and, more specifically, toxicity. The first is that chemical effects are not binary. A single chemical is neither bad nor good, neither safe nor unsafe. The effect of a chemical on the human body arises from a combination of its toxicity multiplied by the quantity absorbed by that body (more poetically: “the dose makes the poison”). Simply put, high levels of sugar can be “unsafe,” while low levels of arsenic are “safe.”
The second idea lacking is risk analysis — an understanding that each person faces a host of low risks daily that can lead to illness, injury, or death. Each risk can be stated as a probability — one chance in a thousand per day, one chance in a million per year, one chance in a million per lifetime, and so on. These chemical risks are an unavoidable part of everyday life. Everything we touch, hear, see, smell, or taste is made of atoms, and, therefore, has a chemical nature. Everything around us, including our bodies, is made up of chemicals. A container labeled “vanilla extract,” “dried tomato,” or “organic” contains just as many chemicals as a container labeled “polyethylene glycol,” or “methyl paraben.” Many people believe that recognizing the name of the chemicals they consume protects them from risk, but it doesn’t. Even water and oxygen and other "natural" substances can be poisonous in sufficiently high levels. And substances generally considered harmful can have positive (or non-negative) effects in small, controlled doses — warfarin, for example, initially introduced as a pesticide against vermin is now used to treat blood clots in humans (and appears on the WHO List of Essential Medicines for a health system).