“Safe by design” approach: a new Eldorado?

Safe by design approach: a new Eldorado?

The “safe by design” approach, kézako?

The “safe by design” approach aims to minimize the risks of nanomaterials from their design, by modifying:

• their size or structure (via the formation ofaggregates or dagglomerates which bind the nanoparticles together), for example to prevent the passage of titanium dioxide nanoparticles into the skin for sunscreens
  
• and/or their surface – for example by coating or encapsulating the nanoparticles – in order to minimize their potential reactivity (and therefore their toxicity) and to stabilize it throughout the life cycle of the nanoproduct.

Originally promoted by American scientists¹Beyond Implications and Applications: the Story of 'Safety by Design', Nanoethics, 2009, 3(2): 79-96., it has won the favor of European authorities (in particular the Joint Research Center²Impact of Engineed nanomaterials on health-Considerations for benefit-Risk Assessment, EASAC & JRC, Sept. 2011, the European Commission³Work Program 2013, Theme 4, Nanosciences, nanotechnologies, materials and new production technologies – NMP, European Commission, July 2012), and French organizations such as the Center for Strategic Analysis⁴See the 5th recommendation of the Analytical note 248 – For a responsible development of nanotechnologies from the Center for Strategic Analysis, November 2011 or the Academy of Technologies⁵See Risks of engineered nanoparticles, Academy of Technologies, April 2012 who in turn encouraged the development of this approach.

Before the marketing success of this Anglo-Saxon designation, there was already an older incentive from the European Union in favor of clean processes, or from the INRS in France, for example, which has long been promoting "risk prevention from design".⁶Medium Term Plan, 2003-2007, Inrs.

The “safe by design” approach, the solution to all problems?

An alternative to nano risk assessment? 

The "safe by design" approach is presented as a alternative to nano risk assessment as it has been practiced so far : insufficiently organized, confronted with methodological difficulties, it led to results that are difficult to use, many of which relate to insufficiently characterized nanomaterials⁷About 80% of nanotoxicology studies before 2007 did not sufficiently describe the different characteristics of the nanoparticles studied: Cf. "We must define what a nanoparticle is", Interview with Eric Gaffet, research director at the CNRS, Health & Work, No. 071 – July 2010 and without it necessarily being known whether they were present in products actually marketed.

A case-by-case approach involving high cost 

The "safe by design" approach is also presented as a more powerful solution than the so-called "case by case" approach widely advocated by the scientific community to health and environmental agencies in recent years⁸Justified by concern for take into account the particularities of each nanomaterial, this “case by case” approach proposes to better take into account:
– the different physico-chemical characteristics of nanoparticles (size, shape, structure, state of charge, degree of agglomeration, composition, solubility, etc.) which play a determining role in their toxicity and eco-toxicity
– the conditions under which the nanoparticles are synthesized, stored, possibly coated, then integrated into a product and which influence the characteristics and therefore also their toxicity and eco-toxicity but lately decried by some scientists who consider it too expensive, too long and irrelevant because assimilated to an endless quest.

Proponents of the "safe-by-design" approach argue that by playing on the way nanoparticles are synthesized, coated and then integrated into a product, it will be possible to develop nanomaterials whose physico-chemical characteristics will make them safe materials from a health and environmental point of view.

An approach largely supported by public funding 

A reassuring argument… which explains why the application of the “safe by design” approach to nanotechnologies and nanomaterials is supported by public money.  

There are still many scientific challenges

Especially since we should not err on the side of optimism: the "safe by design" approach will not be free from scientific and technical difficulties.¹⁴François Tardif of the CEA considered in November 2011 that “it will still take years to identify benign nanoparticles, See: Safety of Nanomaterials, Exposure Reduction State of the art and developments, François Tardif, presentation at the day “Views on nanotechnology: challenges, debates, perspectives”, Institute for Risk Management, October 18, 2011. A few months earlier, American scientists insisted on the fact that the nanomaterials being developed and to come will be much more complex than current nanoparticles and present challenges that will have plenty to keep toxicologists busy for the next fifty years, See: The new toxicology of sophisticated materials: nanotoxicology and beyond, Maynard Ad, Warheit DB, Philbert Ma., Toxicol sci., 2011.

The "safe(r) by design" approach will not be able to control everything, in particular because a large number of factors are beyond the control of researchers and engineers:

• First, the conditions under which the nanomaterials are used and then released, transformations they can undergo in the environment or in the body, etc.¹⁵In order to be able to design "safe" nanomaterials, the Serenade labex shows that it wants to “understanding the mechanisms of interactions between inert matter (nanoparticles) and living matter (cells down to the level of chromosomes and DNA)”Labex SERENADE 2012, “Towards a design of innovative, sustainable and safe nanomaterials”, presentation of the Ministry of Research. This is in fact one of the aspects which have so far been little studied and of which much is unknown today (especially on the release, as well as on top the fate and behavior of nanomaterials in the environment and in the body), although essential to know if one wants to be able to claim to minimize the risks. It requires the development of experimental approaches reproducing more realistic exposure conditions than those that have been commonly used.
  
• Moreover, by “isolating” or modifying nanomaterials, it is indeed difficult not to lose the advantages of their specificities at the same time.

However, paradoxically, the objectives pursued are both extremely ambitious but presented with an assurance and a fervor (candor?) that minimize the complexity of the task. The following questions then arise: can the challenge be met – both technically and financially – within a reasonable timeframe? When will the projects currently being deployed bear fruit? And with what guarantees as to the real harmlessness of the nanomaterials developed? Isn't the idea that we can totally control the risks by an irreproachable design illusory?

So many important questions. Waiting, nanoproducts continue to be marketed, without further information on their risks or safety.

Behind the technique, questions and political choices

These non-technical but political questions, which have given rise to strong controversies in the case of GMOs, are still little discussed with regard to nanotechnologies. However, they constitute important issues: the question arises in particular of the choice of distribution of public funding between the various fields of research and the aims pursued (toxicology, eco-toxicology, environmental health and health at work on the one hand, innovation and competitiveness of the other), and that of funding methods for research projects to secure nanomaterials.

Finally, as William Dab wrote at the end of 2013, “it is very difficult, if not impossible, to demonstrate the non-existence of a danger. It's much more difficult, in fact, than proving its existence. It is a very disturbing situation and leaves room for speculation and confrontations often underpinned by struggles between contradictory interests. (…) harmlessness cannot, strictly speaking, be demonstrated. (…) science does not have all the answers. Therefore, we must not hide the uncertainties, but on the contrary, put them at the center of "scientific democracy", you might say. Which means debate what is or is not a risk, what is a risk worth taking« ¹⁶Can we demonstrate the non-existence of a danger?, William Dab, Of Risks and Men, December 9, 2013 .