Missing from this answer is the early evidence that they may be _very_ harmful. Early evidence suggests they are not non-reactive. They disrupt many of the body's systems in ways we're only beginning to understand.
> Various examples of damage caused by microplastics have been reported, such as microplastic accumulation in the bodies of marine and aquatic organisms (leading to malnutrition), inflammation, reduced fertility, and mortality. The threats that microplastics present to the human body have not yet been clearly identified. However, previous reports have shown that ultrafine microplastic absorption resulted in complex toxicity in zebrafish,2 and that microplastics under 100 nm in size can reach almost all organs after entering the human body.3 Therefore, concerns exist regarding the negative effects of continuous microplastic accumulation in the human body.
> Microplastics have been found in a variety of organisms and multiple parts of the human body. We emphasize the potential impact of microplastics on the early exposure of infants and the early development of embryos. At present, the toxicity research on microplastics show that the exposure will cause intestinal injury, liver infection, flora imbalance, lipid accumulation, and then lead to metabolic disorder. In addition, the microplastic exposure increases the expression of inflammatory factors, inhibits the activity of acetylcholinesterase, reduces the quality of germ cells, and affects embryo development. At last, we speculate that the exposure of microplastics may be related to the formation of various chronic diseases.
So...perhaps worthy of further study, maybe including to understand where exposure comes from, and whether the particles are absorbed? Like this study.
Unclear doesn't mean safe, it just means hard to quantify. Your child could be in a car accident and their survival odds could be unclear, scientifically speaking. Doesn't mean "totally safe."
This is the wrong analogy because the article states that there's only theoretical harm. It could mean that one has to drink from 100 tea bags a day to get any adverse effects.
It’s reasonable for people to take either approach: are microplastics more like asbestos or are they more like cellulose in terms of harm?
The answer being unclear means it makes sense to treat them, from a regulatory standpoint, closer to asbestos. It also makes sense to treat them as an unknowable and not regulate, because any alternative might be worse.
But it does point to there being a dearth in research and answers, and we should solve that as quickly as possible and maybe limit our exposure when viable, known to be non-toxic alternatives exist.
>The answer being unclear means it makes sense to treat them, from a regulatory standpoint, closer to asbestos.
I'm not sure the follows logically, it ignores a bunch of known facts about biology to imagine that there is a pathway for these to cause major issues.
Damage that is bad enough becomes easy to quantify, so no, "unclear" actually does put a bound on it.
Survival odds in car crashes demonstrate this nicely: count the outcomes and divide. If "the survival odds were unclear, scientifically speaking" then car accidents would have to be orders of magnitude more rare and less lethal than they are.
Sudden damage that is bad enough is easy to quantify. You should take a look at the decades long struggle to prove that cigarettes are harmful to see what it is like when the harm is chronic.
Was the most important part of all the tobacco research the bits that said “Smoking tobacco is healthy”? Or the studies of lead in gasoline the caveats that said “These are small samples”?
It removes the possibility of fear mongering. I'm not aware of any modern research where smoking anything is claimed to be healthy, nor anything about lead in gasoline being too insignificant to pose a health risk.
What is that supposed to mean? Most science is based on theories but you don’t wait for the Theory of Everything to take learnings of science. Fear is a very useful emotion and you shouldn’t fear it.
You are mistaking "theories" and "hypotheses". Theory in science is not some wild shot in the dark, imagined by some random guy in the eureka moment. And neither it is a something yet unproven. Theories in sciences are usually sufficiently proven and stand on the other previously proven theories. Like for example evolution of species is a theory, despite it having more than a century of research and hard proofs. So yeah, science is based on theories, but not on a collection of lucky guesses.
Now hypothesis is what you were probably mistaking a theory with. A hypothesis is something unproven and may or may not be a real thing.
I did mistaken those, thank you for pointing that out. My point remains that science operates in the real world, where decisions often have to be made based on incomplete evidence, rather than waiting for certainty.
I won't speak for the whole world, but the amount of plastic things around me increased by a couple orders of magnitude in the last 15-20 years. What used to be made of stainless steel, wood or paper is now often made of plastic: tea kettles, dishes, water pipes, food bags, etc. etc. We'll see what effects it has in another 15-20 years when it will be too late to do anything.
'Plastic' is a loaded term. It includes lots of different types of platic, as well as intentional (plasticizers) and unintentional (residue in recycled plastic) additives to it. Some of the formulations are fairly new, some have been in use for a long time.
The amount of exposure has also changed. Some bakelite knobs on your armoir aren't a big deal. Sleeping with a 'fleece' blanket and inhaling polypropylene all night every night may not be fine.
Personally, I don't have confidence in being able to be an informed consumer of plastics, and it's easier to just minimize platic use in general without trying to decide what's dangerous and what's ok.
That's overly simplistic. The negative health effects might be lagging, because when plastic was invented there were zero micro plastics in the environment and now there are lots.
To wit, life expectancies in North America have been declining the last few years.
I see your point, but I suspect it's at least equally valid to assert that our average lifespans also fell due to COVID. Mortality isn't the only impact it had, and long term effects linger.
Maybe it does and maybe it doesn't but the fact remains it's overly simplistic to assume that plastic production doesn't temporally lead changes in health effects by some amount.
It's almost like life expectancies cannot be explained by a single variable, and the original claim that life expectancies went up thus plastics aren't bad is overly simplistic. Imagine that.
Actually, it's not even that as most of the modern increase in life expectancy / fall in mortality occurred before the invention of plastics.
The former largely concluded by the 1920s. Plastics were largely invented during the 1930s, and were introduced as products over subsequent decades, at an ever-increasing rate.
Which is to say: whatever lead to the increase in life expectancy was largely not plastics. Rather it was increased general hygiene, sanitation, food quality, refrigeration, waste removal, and sewerage systems.
I'd mentioned this only a few months back, note especially my follow-up comment which similarly points out another frequently-touted factor which also fails the temporal sequencing test:
I'm not saying it's harmless, I'm saying that even if it is harmful it's not by enough to justify the panic and sudden lifestyle changes these articles sometimes lead to.
Remember the black spatulas a while back, and how it turned out to be a math error?
Is scooping out your food out of the crappy plastic takeout container into a bowl before microwaving an example of “panic and sudden lifestyle changes”?
Seems like a pretty minor change to me. I’m already going out of my way to not put metal in there anyway…
Humans existed. They had an average life expectency of 'x'. Then we introduced plastic. The life expectency became x+y.
We cannot say that plastic caused the increase, but it is clear that any decrease was small enough to be hidden by other factors.
Am I saying that it's harmless? No. Am I saying that your effort and attention are better spent checking your fire extinguishers arent expired or that your brake pads don't need changed? Yes. Those things have significant and obvious impacts on your survival odds. This does not.
> but it is clear that any decrease was small enough to be hidden by other factors.
Yes, but those "other factors" being antibiotics and vaccine, it turns out that even the deadliest pollutants we know were hidden by other factors, so it really gives us no idea about how harmful it is, as it could go from "harmless" to "cause millions of death every year" that's why I say the argument makes no sense.
> Am I saying that your effort and attention are better spent checking your fire extinguishers arent expired or that your brake pads don't need changed? Those things have significant and obvious impacts on your survival odds. This does not.
That's the problem, you cannot make this conclusion at all, it could be much worse than those two while still being hidden in longevity statistics, just because antibiotics and vaccine has so strong of an effect on life expectancy! Having no fire extinguisher at home has pretty much no impact on your life expectancy, but at the time plastics were introduced a significant fraction of the newborn didn't reach 10yo because they died of an infection of some sort.
> it could be much worse than those two while still being hidden in longevity statistics
I see what you mean, and I think we're basically coming at the same point from different angles. If you are a medical researcher or involved in crafting legislation this is probably important. You could help save millions of lives in aggregate. However, I'm suggesting that individual people should think of the opportunity cost before they panic. After all, a person can only worry about so many things and almost everyone is at or past their capacity.
To use another half baked example, if plastics take away a year, and antibiotics give you 5 extra you still win. However, if smoking cigarettes, obesity, or driving too fast risk taking away 10 years, start with one of those first.
Optimizing the bits of life that are too small to reliably measure is just not a great way to live, unless you've already handled all of the low hanging fruit in your life. Anxiety kills people too.
> Various examples of damage caused by microplastics have been reported, such as microplastic accumulation in the bodies of marine and aquatic organisms (leading to malnutrition), inflammation, reduced fertility, and mortality. The threats that microplastics present to the human body have not yet been clearly identified. However, previous reports have shown that ultrafine microplastic absorption resulted in complex toxicity in zebrafish,2 and that microplastics under 100 nm in size can reach almost all organs after entering the human body.3 Therefore, concerns exist regarding the negative effects of continuous microplastic accumulation in the human body.
https://pmc.ncbi.nlm.nih.gov/articles/PMC10151227/
> Microplastics have been found in a variety of organisms and multiple parts of the human body. We emphasize the potential impact of microplastics on the early exposure of infants and the early development of embryos. At present, the toxicity research on microplastics show that the exposure will cause intestinal injury, liver infection, flora imbalance, lipid accumulation, and then lead to metabolic disorder. In addition, the microplastic exposure increases the expression of inflammatory factors, inhibits the activity of acetylcholinesterase, reduces the quality of germ cells, and affects embryo development. At last, we speculate that the exposure of microplastics may be related to the formation of various chronic diseases.
https://pubs.acs.org/doi/10.1021/envhealth.3c00052