Nanosilver has been one of the great success stories of nanotech, with applications from socks to washimg machines, so perhaps the greatest surprise is that it took so long to attract the attention of environmental groups and regulators. The target of their wrath is Samsungs nanosilver washing machines, which apparently release some 0.05 grams of silver into the environment per machine per year.
Is that a problem? It’s hard to tell. Larger amounts are probably finding their way into the environment via other routes such as medical and textile waste where nanosilver has been used for a number of years, not to mention the huge amounts stored up in other consumer goods from air conditioners to refrigerators. Nanosilver has alos been used in products such as toothpaste and toothbrushes, so it is an opportune time to start asking the question.
The US EPA jumped in on Wednesday saying that it was changing federal policy to require that “manufacturers provide scientific evidence that their use of nanosilver won’t harm waterways or public health” – a statement that appears to require manufacturers to prove a negative.
Rather oddly, the EPA also concluded that “the release of silver ions in the washing machines is a pesticide, because it is a substance released into the laundry for the purpose of killing pests,” which also seems to class anti antibacterial or anti fungal agent as a pesticide.
This looks rather bizarre so we are obviously not getting the full picture here . We will have to wait an see what sense emerges from this, but it seems to be the old struggle between progress and proponents of the precautionary principle which states:
“When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically. In this context the proponent of an activity, rather than the public, should bear the burden of proof. The process of applying the precautionary principle must be open, informed and democratic and must include potentially affected parties. It must also involve an examination of the full range of alternatives, including no action.”
No activity can be reduced to zero risk, and taking the precautionary principle literally would set civilization back some 40,000 years as building fires and hunting game armed only with a blunt stick are rather risky activities. What is needed but so often lacking in these debates is some scientific evidence upon which a rational assessment of any risks and potential benefits can be based.