From the Directors Desk (Spring 2013)

No items found.
Back to Dignitas Issue

Did you know there are nanoparticles in our food?” my husband asked me this morning. “Oh?” He added, “It’s used to make the frosting on donuts extra white.” I might have added, “and chocolate flavored chewing gum.

What Are Nanoparticles?

Why does this matter? Isn’t this a debate about taste, not bioethics? Not necessarily. Nanoparticles and nanotechnology exist in the realm of the very small, but the ethical issues loom large.

“Nano” refers to size. Nanoparticles are too small to be detected with a regular microscope, measuring between 1-100 nanometers (nm). (One nanometer is one-billionth of a meter.) The scale is hard to imagine: one human hair is about 80,000 nm wide. Nanotechnology is the engineering of particles at the near-molecular level. At this size, the chemical, biological and physical properties of matter change. For example, aluminum is a safe, nonreactive material for packaging carbonated beverages. At the nanoscale, aluminum is highly reactive, even explosive. In addition to reactivity, nanoscale affects electrical, optical and thermal properties.

The change in properties makes nanoparticles valuable for a variety of applications. “Gold, for example, is inert in bulk but becomes highly reactive at the nanoscale, making it a potentially valuable catalyst.”[1] Carbon nanotubes are the strongest fibers known. They are 10-100 times stronger than steel. And, depending on how it is rolled up to make the tube, carbon can act either as a semiconductor or as a metal.

What Should We Do with Them?

Nanotechnology is used to target drugs at specific cells, to eliminate odors in sweat socks, to help sunscreen penetrate better, to make e-paper, to improve packaging materials, to make paint that is scratch resistant, and, yes, to make food.[2] The whitener in the donut frosting is titanium dioxide, which also shows up in candy, gum, pudding, and paint.

We appreciate what nanotechnology gives us. There is the convenience of wrinkle-free clothing. Nanorobots to deliver cancer drugs to only cancerous cells would eliminate the more dreadful side effects of chemotherapy. Nanotechnology is responsible for lengthening battery life and making scratch resistant sunglasses. It may be the key to providing clean and safe drinking water.

With this seemingly limitless cornucopia of benefits, why the concern?

The very qualities that make nanoparticles attractive also render them chaotic and unpredictable. Rather than binding to larger molecules or cells, nanoparticles are able to penetrate the cellular barrier, the blood-brain barrier, and the placental barrier. Their cumulative effect on human tissues is unknown. Environmental and health hazards are nearly impossible to predict.

Let me suggest one of several ethical themes: caution.

Where there is uncertainty about consequences, whether unintended or unknown, and there is potential for significant harm, the precautionary principle applies. The risk from nanoparticles escaping from sunglasses, paint or other coatings is unknown. The pollution potential from free-floating nanoparticles is also unknown. Eric Drexler, the father of both the science and neologism “nanotechnology,” warned that uncontrolled nanorobots could rapidly replicate, consuming all the carbon atoms in matter, turning the world into a lifeless mass of “gray goo.”[3]

Although his specific concern has been refuted by others, the broader need for caution remains. One study of mice has found that inhaled carbon nanotubes are more toxic than silicon particles. Pat Mooney, executive director of the ETC Group, says, “All of these [studies] say there is a yellow light here.”[4] Yellow means caution; go slowly.

Dónal O’Mathúna suggests that the precautionary principle “does not try to stop or slow science, but encourages it in certain directions.”[5] This means taking moral responsibility for risk assessment and compensation should harm occur. How that can be accomplished is itself uncertain. Risk assessment may be cost prohibitive for the manufacturer and therefore the customer; it takes time for nanoparticles to accumulate; and we lack technology to detect their presence.

The burden of proof for safety should be on the one introducing nanoparticles or processes, and the entity that introduces the nanoparticles should pay for adverse health and environmental consequences. As consumers we may object to higher prices, but the price of not paying attention to risks is even higher.

Government regulation adds a layer of complexity. Nanotechnologies are so diverse, they cannot be easily categorized and frequently involve multiple disciplines and expertise. There is no single “nanoindustry,” and therefore no industry-wide standards. Which agency or agencies should have oversight responsibility? Nanoengineering can enter at a variety of points in the process, and the final manufacturer may not even be aware of nanoparticles in the product. Full disclosure at each step, including labeling of the final product, could help us to notice and take nano more seriously.

Government-sponsored research into environmental impact and the effects on the human body of products that have already entered the market may be warranted. For example, the Food Standards Agency in the UK, which assesses new foods, is researching how “nanomaterials enter the human body and what happens to them once they are there.”[6] The agency commissioned an ongoing study that investigates whether titanium dioxide (the donut frosting whitener) is absorbed into the gut.[7]

There is also the ethical matter of personal responsibility. Staying abreast of major “nano-developments” is as close as Google. And, those of us in the various scientific disciplines need to get out of the research labs, and notice what is happening in the lab down the hall or across the ocean.

We cannot rely on science to guide itself. As Eric Cohen writes, “Science is power without wisdom about the uses of power.”[8] Wisdom and the wise use of technological power are matters of ethical concern and, when they affect human bodies, matters of bioethics. Whether in our favorite Dunkin’ Donuts treat or nanorobot-delivered chemotherapy, nanoparticles matter.


[1] Robert Service, “Nanotechnology Grows Up,” Science 304, no. 5678 (June 18, 2004): 1721.

[2] See, for example, Heather Miller, “Nanoparticles Are in Our Food, Clothing and Medicine—And No One Knows for Sure How Dangerous They Might Be: Inside Nanotechnology’s Little Universe of Big Unknowns,” AlterNet, February 23, 2013, (accessed April 4, 2013).

[3] K. Eric Drexler, Engines of Creation: The Coming Era of Nanotechnology (New York: Random House, 1986), 172-173.

[4] Service, 1733.

[5] Dónal P. O’Mathúna. Nanoethics: Big Ethical Issues with Small Technology (London: Continuum, 2009), 83.

[6] “Nanotechnology,” Food Standards Agency, (accessed April 4, 2013).

[7] “Human In Vivo and In Vitro Studies on Gastrointestinal Absorption of Nanoparticles: The Effect of Size and Surface Properties (Ongoing),” Food Standards Agency, February 25, 2010, (accessed April 4, 2013).

[8] Eric Cohen, In the Shadow of Progress: Being Human in the Age of Technology (New York: Encounter, 2008), 21.