While titanium dioxide particles in sunscreens are considered safe (see my blog posting here), there is a new study which suggests concerns. A study was done in Japan on pregnant mice who were injected with titanium dioxide nanoparticles. The results suggest that the particles affected brain development in the foetuses. (The media release is located at Nanowerk News here.) My questions since I haven’t looked at the study are this: Where was the injection site? What was the concentration of titanium dioxide nanoparticles in the solution? Where several concentrations used or only one? (After all, a lot of medicines are poison if taken in the wrong dosage or misapplied [taken internally instead of externally].)
Still on the titanium dioxide trail, there’s a study by researchers in Switzerland which suggests that nanowires and nanotubes made of titanium dixoide are toxic. There’s an article by Miichael Berger here on Nanowerks. From Berger’s article,
One of the complications of nanotoxicology is that the toxicity of a specific nanomaterial cannot be predicted from the toxicity of the same material in a different form.
…
“TiO2 nanoparticles are widely used as UV blockers in sunscreens” says Arnaud Magrez [researcher]. “Their cytotoxicity has been tested before and they were found to be rather non-toxic. Our new study shows that TiO2 based nanofilaments, however, can be quite toxic. The geometry of nanoparticles appears to play a crucial role in cytotoxicity. Furthermore, the toxicity can be enhanced by the presence of defects on the nanofilament surface, resulting from chemical treatment.”
Both of these studies highlight why more research needs to be done. A comment which is made in an entirely different context by Dr. Andrew Maynard in his essay commemorating the anniversary of the Royal Society/Royal Academy of Engineering 2004 report on nanotechnologies. Maynard’s essay is the foreword to a report, 5 years on – a beacon or just a landmark? Reflections on the 2004 Royal Society/Royal Academy of Engineering report into nanotechnologies – what was its impact and what is its legacy? published by the Responsible Nano Forum. Maynard’s essay can be read here on his 2020 Science blog and the report can be found here. From Maynard’s essay,
At the time, concerns were mounting over possible new risks associated with creating materials and devices at the nanoscale, and how these would affect the technology’s development. The previous year, Michael Crichton’s book Prey had sent the nanotech community into a tizzy over a speculative public backlash against the emerging science and technology. And researchers were beginning to reveal hints that novel nanoscale materials could also affect humans and the environment in unconventional ways—getting to places and causing harm on a scale that belied their small size.
Do read it if you have the time. Maynard’s perspective is both historical and contemporary.
And now for something which concerns me when writing this blog, copyright. Since this blog isn’t profitmaking and I give attribution and encourage people to visit the sites and blogs I quote from, I’ve considered what I do ‘fair use’. If you’ve been following the copyright discussion, you know ‘fair use’ is being debated fiercely as is intellectual property law which includes copyright, patents, and trademarks.
After a rather disastrous attempt to introduce new copyright legislation (last fall I think), the Canadian government has launched a public consultation process. (I too was surprised to find out about it.) The roundtable meeting in Vancouver took place about 10 days ago. There will be roundtable meetings elsewhere and two town hall meetings (where the public will be invited). If you’re a member of the public who’s lucky enough to live in either Toronto or Montreal, you can have your say in real time. The rest of us can participate online here at the Copyright Counsultations website. You do have to register to participate. The Vancouver roundtable meeting has been transcribed and is available online here and the trasncript for the Calgary roundtable is here.
Greetings Frogheart – good on you for managing to think in this heat. Good questions with respect to the Japanese study on titanium oxide sunscreens. Another question that always needs to be asked is ‘who says so?’ – and who paid for it? Today there was much fuss made about a British study that found organic food (produce mostly I think) was no more ‘nutritious’ than the conventional kind. Aside from the obvious difficulties inherent in meta analyses when one compares apple and donkeys as someone once said, I am curious as to who funded the study. The title of the institute in question is vague and for all any of us know could be a biscuit company or some large agribusiness consortium ..
Similarly, with this Japanese study, given its timing – when what sounds like a non partisan has weighed the evidence on nano particles in sunscreens just came out – and emotive tone, my first question would be: did some company with a vested interest in the other sunscreens pay for it? or at least support it?
Just wondering .
As you say, perhaps titanium oxide can be harmful in major quantities to a developng foetus in a mouse – bearing in mind that mice are not people and endocrinologically, they do not resemble humans at all.
One study does not a proper doubt make.
Hi BaxDoc! Thanks for adding a couple more questions that should be asked when questioning research. Of course, the source for funding research is an important issue as you point out in your examples.