With the profusion of information available on the Web, search engines have become a key mediator by directing people to the information they're interested in. But that has also turned the search engines into gatekeepers; both by ranking the results and by offering suggested search terms, the sites can subtly (and, in some cases, not so subtly) influence the sorts of information that a significant fraction of the public will encounter. A new survey of Google search terms looks into how this is playing out when it comes to information on nanotechnology. The researchers found that both suggested queries and search results may be pushing that field down a path that is similar to the one that was traveled by genetically modified foods, where an initial focus on technology and applications has been replaced by worries about health and ethical issues.

Nanotechnology is a sprawling field that is based on a simple observation: the properties of many familiar materials are completely different when they are structured at the nanometer scale. So, for example, differences between bulk gold and gold nanoparticles include color, melting point, and electronic properties. Our ability to control the bulk production of nanostructured materials is a relatively recent development, and it holds both promises and risks.

On the promising side, the distinct properties are being used in areas like industrial catalysis, harvesting solar energy, and targeting medical interventions at the cellular levels. At the same time, the fact that even familiar materials have unusual properties at the nanoscale raises the risk that a nanotech version of a substance we view as innocuous may pose health risks.

How is this balance of potential and risk playing out in the world of Google? The authors claim to detect a shift away from basic interest in the technology and its use, and towards health issues.

The authors surveyed search results and suggestions in both October 2008 and August of 2009. At the earlier time point, there are three terms related to economics in the top-10 list: stocks, jobs, and companies. Three neutral terms (research, future, and applications), also cracked the top 10, while "nanotechnology medicine" was in 10th place. Less than a year later, things were radically different. Medicine had moved up to sixth place, and cancer cracked the top 10. "Nanotechnology companies" was the only economic term still on the list.

Search suggestions provided by Google would seem likely to reinforce this trend. "Nanotechnology in medicine" was apparently the top suggestion from Google, even though it wasn't the most frequently searched term. "This difference between Google suggestions and the top searched keywords is not trivial," the authors argue, "given that the ranking of Google suggested terms is likely to influence citizens' searches related to nanotechnology."

The authors also performed a detailed analysis of the links returned by Google, along with the links present in those pages, placing them in one of 10 possible categories. Overall, there was a strong bias towards health-related material in the Google results, and one that appears to have increased over the course of the time period in question. Some of this health material was presented even when the initial search terms had nothing to do with health.

The authors suggest that we've seen this pattern before. Their own research into the portrayal of plant biotechnology indicated that news coverage started off focused on the technology itself and the business opportunities it presented. By the late 1990s, however, the focus had shifted entirely to health concerns and ethical debates, where it largely remains today.

There are a few limitations of this analysis, most notably its attempt to extract a trend out of a year's worth of data. There's also a notable absence of detail when it comes to precisely what's being said about nanotechnology and human health. In contrast to plant biotechnology, many of the proposed applications of nanotechnology have very direct and obvious applications to medical therapies, where preliminary studies of nanoparticles have already demonstrated their ability to mediate targeted killing of cancer cells. So, the focus on health may be at least partly a product of these relevant applications.

The other notable thing is that a shift away from basic science and towards health is occurring throughout the media landscape. CNN eliminated its science staff, but retains health coverage; The New York Times merged its science section in with health coverage several years ago. Google may not be driving the trend here so much as reflecting it.

The prospect that Google could be in the driver's seat when it comes to the public perception of science, however, shouldn't be completely discounted. In a small experiment of my own, I checked the suggested searches that appeared in response to "climate." The only results for specific sites devoted to climate change that appeared all directed me to sites that promote views contrary to those held by most scientists. The top offering was for "climategate," which is generally viewed as an event that gave the scientific community a black eye. Anyone who relies on Google's suggestions for their reading list is unlikely to come away with a good sense of the current science.

Materials Today, 2010. DOI: 10.1016/S1369-7021(10)70084-5 (About DOIs).