Just because chemical equipment can measure parts per trillion doesn’t necessarily mean that they have any biological significance. If you took one pill of Tylenol and dissolved in an olympic-size swimming pool, that would roughly be 1 part per billion. One part per trillion would be one pill in 1,000 swimming pools. My point is that it is very hard to think in such fantastically small quantities, and it takes much more rigorous biological thinking to make scientific sense of the kinds of claims made in articles such as this one.
From the Nature Index
Subscribers, enter your e-mail address for full access to the Science News archives and digital editions.