Letters to the editor
More on microplastics
I found the article on microplastics (C&EN, Feb. 4, page 28) to be well written and informative, albeit scary. It seems to me that the topic cries out for more study, particularly on a few subjects that were just touched on in the piece; in particular, (1) can microplastics be detected in human or animal blood, and if so, can they pass the blood-brain barrier? and (2) vegetarians are mentioned as not being included in the small group of eight that were the subjects of a paper (undergoing peer review) for gut contamination by plastic, but it seems they too might not be exempt from this contamination in view of the leaching of plastic from packaging and the use of animal and human sewerage on crop-producing fields. So there may be no easy dietary safe choice to pick in avoiding this pestilence! Kosher foods (like that wonderful pastrami) would not be exempt.
Along with plastics come embedded plastic additives, some likely to interfere with human or animal endocrine systems, as the C&EN piece mentions; others, like oleamide (used as a release agent in plastic molding) could have even more serious consequences for humans and animals in that oleamide happens also to be naturally occurring in the brains of cats and likely humans, where it may regulate sleep.
It seems to me that, along with global warming, humans may have unleashed another apocalyptic plague on Mother Earth in the form of plastics. It has become a ubiquitous contaminant in the environment, particularly our oceans. Mass spectrometrists will confirm that few study samples are free of plastic additives (such as phthalates, nonylphenols, and bisphenol A). It is maybe the closest analogy we have to a Pandora’s box; along with the many advantages that plastics offer over glass or metal in our daily lives, we are seeing a serious downside that could be detrimental to animal life and possibly human life itself, as the C&EN article cautions.
I hope there will be a follow-up piece soon by C&EN on the analytical tools and techniques—their potential and problems—that are being brought to bear by the chemical community on dealing with this perceived problem.
Thomas F. Spande