Nanomedicine: new solutions or new problems?

(Nanowerk News) A new report from Health Care Without Harm ("Nanomedicine: new solutions or new problems?"; pdf) gives an overview of nanomedicine in general with particular emphasis on environmental and human health risks, as well as raising regulatory issues that need to be addressed in order for nanomedicine to deliver on its promises without unduly introducing new risks.
report cover: Nanomedicine: new solutions or new problems?
Executive Summary

Nanotechnology, the science and business of manipulating matter at the atomic scale, is positioned to initiate the next industrial revolution. Already, nanotechnology products are starting to be used in many areas of everyday life, including in the healthcare sector. A wide variety of commercial applications are already on the market, and continuing investment in research and development will undoubtedly lead to further innovation and a multitude of uses.

In the healthcare sector, nanomaterials offer the prospect of a wide range of medicalapplications, such as improved drug solubility, drug delivery systems, cellular and tissue repair systems, diagnostic and imaging tools, and therapeutic medicines that can target specific diseased tissues within a patient’s body. Nanoscale healthcare and pharmaceutical applications and products (collectively known as nanomedicine) are becoming more prevalent and a number of products have already reached clinical use.

Nanomaterials are engineered to take advantage of unique properties at the nanoscale (where at least one dimension is measured in billionths of a metre). Size is a key property of nanomaterials and nanomedicines because it confers a large increase in surface area, which in turn results in novel properties of the material when compared to the same material at a larger scale. Thus a nanomaterial may have greater chemical and/or biological reactivity or catalytic activity. While these new properties may be very useful, changing materials at this scale can also result in the introduction of new toxicological risks.

While a greater surface reactivity and solubility or the ability to cross biological barriers such as the blood-brain barrier may be desirable behaviours for a nanoformulated drug, these properties may be less desirable once beyond a specific treatment site within a patient or if the drug enters the environment.
It is therefore essential to understand and monitor the bioavailability, bioaccumulation, toxicity and/or environmental transformations and interactions of nanomaterials. Currently, it appears that standard risk assessment procedures are inappropriate for dealing with nanomaterials and tools for environmental monitoring of such tiny materials have not yet been developed.
This report gives an overview of nanomedicine in general with particular emphasis on environmental and human health risks, as well as raising regulatory issues that need to be addressed in order for nanomedicine to deliver on its promises without unduly introducing new risks.
Health Care Without Harm believes that nanomedicine may offer advantages and innovative solutions to some of our current health problems. However, we are also concerned that some of the new properties of nanomaterial products, while desirable from a strictly clinical perspective, can introduce new risks for human health and the environment. It is impossible for nanomedicines to be completely contained within a clinical/healthcare setting and it is imperative that their whole lifecycle is taken into consideration. Unintentional exposure of workers and associates and environmental contamination may arise during manufacture, use and waste disposal, leading to possible health and environmental impacts which are currently difficult, even impossible, to quantify given the gaps in knowledge, understanding and regulatory control.
The European Union chemical legislation does not specifically refer to nanoscale chemicals and does not explicitly recognise that such materials can have very different properties from the parent “bulk” chemicals. Given the extraordinary characteristics of nanomaterials, Health Care Without Harm believes that they should be regarded as new substances for the purposes of regulation.
A number of specific recommendations are proposed. These are further elaborated in Chapter 6 of the report:
The precautionary principle must underline the regulatory approach to nanomaterials.
The limitations of EU regulatory frameworks must be addressed:
  • Nanomaterials should be classified as new substances in EU legislation;
  • Any definition of nanomaterial should not restrict the size threshold to 100 nm;
  • REACH should take into consideration a need for lower threshold requirements for nanomaterials (i.e., less than 100 g);
  • REACH should require specific dossier data for nanomaterials;
  • Nanomedicines that combine both pharmacological and mechanical functions should be regulated strictly, recognising the risks of both intentional and unintentional releases;
  • Waste management legislation and guidance should be reviewed in light of the need for safe waste disposal of nanomaterials.
  • Nanomaterial characteristics need to be identified and categorized to ensure appropriate testing methodologies.
    Research is necessary to both address scientific knowledge on the safety, fate and persistence of nanomaterials in humans and the environment; and to develop standards, guidelines and tools for the detection and monitoring of nanomaterials and their effects on human health and the environment.
    The entire lifecycle of nanomedicines, including manufacture, disposal and possible environmental impacts, must be taken into account when considering their benefits and risks. For example:
  • Guidelines to assess end-of-life management options are needed, taking into account toxicity and environmental fate;
  • The use of nano-based cleaners and disinfectants should be discouraged wherever feasible as their use will contribute to the exacerbation of antibacterial resistance resistance, along with other unknown consequences for the environment.
  • Patients, workers and communities need full access to information and to be included in decision-making processes. This would include:
  • An EU register listing the production, import and use of nanomaterials;
  • Compulsory labelling of all nanomedicine products;
  • Public participation in decisions relating to the exposure of patients, workers and communities to nanomaterials.
  • Source: Health Care Without Harm