You have probably heard a lot about nanotechnology. Nanomaterials are very small particles making a big splash at the cutting edge of new products. They’re turning up in medicine, cosmetics, electronics, packaging, energy-saving devices, and much more.

Most of what’s written about nanotechnology concerns exciting possibilities and benefits. But what about its environmental impact?

The human race has a long history of using materials without recognizing their dangers. Mercury seemed like a useful medicine for centuries. Asbestos was prized as a fireproofing material long before it was recognized as a carcinogen.

More recently, manufacturers of personal care products introduced gritty microplastics into some of their formulas. Fortunately, it didn’t take long to ban them once their dangers became apparent.

Various nanotechnologies are developing with little regulation. Their potential environmental impact remains unknown. In part, that’s because science has not yet developed clear standards for determining the effects of nanoparticles. Therefore, supporters and opponents press their viewpoints with inadequate technical information.

Scientists have been exploring the environmental impact of nanotechnology almost from the beginning. I find that comforting.

But history is repeating itself. Industry gallops ahead of the science. It has eyes on potential benefits, not environmental concerns. Critics alarmed about possible adverse effects likewise issue their warnings with inadequate scientific basis.

Why? Because it takes a long time for science to design, complete, and evaluate the studies that will eventually provide the facts.  Nanotechnology hasn’t been around a long time.

If it’s too early to describe the environmental impact of nanotechnology, it’s not too early to point out some areas of concern.

The beginning of nanotechnology

Nanoparticles occur in nature. Only recently has anyone thought to look for them and measure them. Let alone try to use them.

The idea of nanotechnology is only about one hundred years old. Richard Zsigmondy, 1925 Nobel Prize Laureate in chemistry, coined the term “nanometer” to measure very small particles. In 1959, Richard Feynman, awarded the Nobel Prize in physics in 1965, proposed manipulating materials at the atomic level.

Japanese researcher Norio Taniguchi coined the term “nanotechnology” in 1974. He wanted to describe processes of making computer chips. It appears to be the first reference to a working technology as opposed to theoretical possibilities.

A nanometer is one billionth of a meter. Nanoparticles are less than 100 nm in size. They can be seen only with electron microscopes. .

Science classifies them in two basic ways: organic vs inorganic and natural vs synthetic. Synthetic nanoparticles can be made deliberately or as an unintended byproduct. For example, burning something produces nanoparticles. Just not the ones with potential commercial application.

Nanomaterials and health

Nanoparticles can pass through cell membranes. When absorbed by cells, they can be toxic. For example, they can cause inflammation and fibrosis.

We already know the kinds of respiratory diseases caused by inhaling microscopic soot particles.For example, science has well documented the effects of soot on miners and other people who work in enclosed spaces.

The effects of other kinds of nanoparticles and the effects of nanoparticles on people working outdoors are less well known.

Some materials, such as titanium oxide, have little adverse effect when they’re large enough to see. As nanomaterials, it might be a different story.

Most studies of the toxicology of nanomaterials have been done on mammal cells. Their effects on plants, other animals, and various microbes remains much less well understood. Silver nanoparticles,  however, are used to kill bacteria.

To summarize, the production, use, and disposal of nanomaterials presents some environmental hazards. How serious? We need not only more studies, but for information to be placed in easily accessible databases for further research.

Some other environmental risks of nanotechnology

I’m not attempting an exhaustive view of the environmental impact of nanomaterials. But nearly everything in our society has its most adverse effects either in disposal or inadvertent emission.

Some nanoparticles end up in landfills. Others, especially those used in cosmetics, accumulate in sewage. Wastewater treatment separates treated water from biosolids, or sludge. Both sludge and the water returned to a lake or river contain nanoparticles. The fate of sludge includes landfills, incineration, land application, or composting as fertilizer.

Global estimates of emission of nanomaterials indicate that 63-91% end up in landfills and 8-28% end up in soil. Some of what is applied to soil will enter groundwater.

About 7% of nanomaterial emissions get into the aquatic environment and about 1.5% into air. Science also lacks appropriate analytical techniques to quantify nanomaterials in the aquatic environment. These rather vague numbers show how much we still don’t understand about nanotechnology.

Once released into the environment, nanomaterials may undergo some kind of chemical transformation. Clearly, adequate analytical techniques, as important as they are, cannot sufficiently predict how nanomaterials will affect the environment. We are a long way from understanding the risks and safety of nanomaterials as well as we understand their benefits.

I have had to search on lots of different terms to find this information. Nearly all of them turn up academic research, government sites, and other sources of reliable information.

I am pleased to report that I haven’t found hysterical warnings from fearmongers, but that only means that they haven’t ranked high the search results for the terms I thought of. The most irresponsible “information” hangs out on social media and in forums.

It would be nice, however, if we could for once restrain our mad rush to exploit new technologies before we understand them.

Sources

Effects of nanoparticles on the environment and outdoor workplaces / Sayed Mohammad Taghavi et al., Electron Physician. November 1, 2013
Nanoparticles in the environment: where do we come from, where do we go to? / Mirco Bundshuh et al., Environmental Sciences Europe. February 8, 2018
Nanotechnology: history and future / JE Hulla, SC Sahu, AW Hayes; Human & Experimental Toxicology. November 26, 2015