2.6.25

Episode Transcript

Speaker 1 (00:01):
Welcome to Radio Wized Diary of Science and Nature. Your
reader is Kelly Taylor. I have articles related to the
topics of science and nature. But first a reminder. RADIOI
is a reading service intended for people who are blind
or have other disabilities that make it difficult to read
printed material. From Popular Science, we have an article that's

(00:23):
called It's not Sci Fi Americans support asteroid defense spending.
This is from January thirty. First, what are the odds
of an asteroid of dangerous dimensions striking the planet if
you wait long enough, it's one hundred percent. And they
don't even have to be especially gargantuan to cause widespread harm.

(00:48):
So called city killers football stadium size asteroids that can
handily vaporize a metropolis with their nuclear weapons style explosion,
disturbingly common in near Earth space. If we do find
that a city killer is barreling toward us, there are
only three possible outcomes. The asteroid hits the planet, impacts

(01:13):
a densely populated area and millions of people perish. The
asteroid impacts a remote spot in the desert or the
middle of the ocean and nobody dies. Or the intruder
is detected well in advance of its destined impact day,
and we somehow manage to deflect it or blow it
to smithereens. On paper, planetary defense is one of the

(01:37):
easier global problems to solve. If you can find earth
bound asteroids in space before they find us, and you've
got the technology available to knock them away from our
blue Marble, or if you are short on time the
technology to obliterate them entirely, then you can rule out
almost all but the smallest asteroid impacts. You can effectively

(02:01):
cancel out an entire category of natural disaster. Remarkably, it
seems we're well on our way to doing just that.
NASA's Double Asteroid Redirection Test or dart rammed and uncrude
spacecraft into a harmless city killer back in twenty twenty two,

(02:23):
successfully deflecting it and demonstrating that humanity can rearrange the
cosmos to keep the Earth safe, and before the decade's end,
an asteroid hunting space based telescope, NASA's Near Earth Object
Surveyor mission will be launched with its infrared eye. It

(02:44):
is set to find almost all the city killers orbitting
perilously close to the planet. Planetary defense is a global imperative,
of course, but for the time being, NASA and by extension,
the United States, is leading the charge. Other players, including
the European Space Agency, Japan, and with their own imminent

(03:08):
DART like mission, China, are also contributing to the fight
against lethal asteroids for the moment, though the world appears
to be America's to say yet. Planetary defense only operates
if the government funds it and has space policies that
prioritize it. NASA's Planetary Defense Coordination Office, which is responsible

(03:32):
for things like DART, the Neo Surveyor mission, and America's
suite of ground based asteroid detecting telescopes, gets funding from
the federal government to work toward all its goals. The
annual funding amount changes year on year, but it's risen
from the single digit millions to well over one hundred

(03:53):
million in just the past fifteen years. Now, it seems
that the Department of Government Efficiency or DOGE, run by
SpaceX CEO and billionaire Elon Musk, is said to take
an axe to much of the federal government. Several agencies
have already been cited as targets, perhaps including, as some

(04:15):
of us suggested, NASA itself, with Musk's frequent overtures about
sending astronauts to Mars, and with tech billionaire Jared Isaacman,
who made the first private spacewalk with SpaceX, being nominated
by Donald Trump to lead NASA, it's also not difficult

(04:35):
to imagine a strong US pivot toward Mars with other
key programs in the Space Agency's perview left in the dust.
Quote elon, get those rocket ships going, because we want
to reach Mars before the end of my term, Trump
said during a campaign rally, according to a video clip
of the speech tweeted by Musk in September. So the

(05:00):
future of America's planetary defense research is uncertain, but there
are reasons to be sanguine. The first is that, as
of twenty twenty two, NASA's Planetary Defense Coordination Office gets
around one hundred and fifty million dollars per year. That's
almost a rounding error on a federal government spending spreadsheet.

(05:21):
As a point of comparison, the Artemis program, which hopes
to get American astronauts back to the lunar surface in
the next few years, is costing tens of billions. For
that low cost, the benefit is extremely high. Defending everyone
on the planet, which is to state the obvious, also
includes America, something that should hold sway with the new government.

(05:45):
But perhaps more importantly, planetary defense has long been one
of the few issues that has had strong bipartisan support,
both inside and outside of Congress. In nineteen ninety eight,
Congress gave NASA a legal requirement to find ninety percent
of the kilometer size asteroids those capable of causing global

(06:08):
devastation orbiting Near Earth as soon as possible. They managed
it in twelve years. In two thousand and five, Congress
also legally required NASA to find ninety percent of the
Near Earth's city killers, a target they are still working on,
but toward which they're rapidly making progress. Congressional acts, caucuses,

(06:33):
and hearings involving planetary defense have often been given support
by Democrats, Republicans, and independents. In Neeo's surveyor in particular,
has garnered immovable bipartisan support in recent years. In twenty
twenty two, NASA's senior leadership, which was struggling to manage

(06:54):
ballooning planetary Science mission budgets, was reluctant to ask Congress
for the full amount out of annual funding for the
Surveyor mission. It needed one hundred and seventy million for
twenty twenty three, but NASA asked for forty million. Congress
gave them more than they requested anyway, ninety million dollars.
That year, several Republicans on the House Science Committee demanded

(07:17):
that NASA make sure the mission gets the funding it needed.
Writing to then NASA Administrator Bill Nelson, they complained that
NASA's senior leadership wasn't doing enough to find potentially hazardous asteroids,
that they had no plan to replace the collapsed Arecibo
Observatory in Puerto Rico, a radar facility that, among other things,

(07:39):
helped characterize asteroids, and seemed to be dawdling with Neo
Surveyor's budget unnecessarily. Referring to the two thousand and five
Act that directed NASA to find those city killers, they
wrote that NASA failed to plan, develop, and implement a
program to achieve this goal. The makeup of the House
of Representatives and the Senate has ebbed and flowed dramatically

(08:02):
over the past three decades, but it seems that no
matter which party has control, planetary defense even if it
lingers deep in the background, gets its due. Perhaps that's
because the benefits of protecting the world from asteroid strikes
is obvious to politicians, especially if the US can take credit.
Or perhaps it's because the Electorate two seemed to be

(08:24):
very keen on planetary defense. In recent years, the Pew
Research Center has surveyed the American public regarding their opinions
on NASA and asked them what its objective should be.
Its twenty twenty three survey revealed that monitor asteroids other
objects that could hit Earth came in at number one,

(08:45):
with sixty percent of respondents saying it should be a
top priority for NASA, although the thirty percent said it
shouldn't be of paramount importance but still something NASA should pursue.
Pew's twenty eighteen survey on the same subject had similar results.
Among respondents, both Democrats sixty four percent and Republicans fifty

(09:08):
seven percent said that monitoring potentially earthbound asteroids should be
a top priority. As it happens, sending asteroids astronauts to
the Moon and Mars ranked at the bottom of the
list of priorities, something that probably won't affect Musk's incorrigible
enthusiasm for the Red planet. At the bare minimum, then

(09:31):
NASA's ongoing planetary defense work should tick along as planned,
with any of surveyor continuing to be funded, as well
as its ground based asteroid questing telescopes. Casey Dryer, chief
of space policy at the Planetary Society, a nonprofit planetary

(09:52):
exploration and planetary defense advocacy group, recently wrote that it's
difficult to predict what's going to happen with NASA during
the second Trump administration. The Artemis program is likely to
be a huge focus during the transition. Planetary defense hasn't
emerged as a talking point for the administration. It is

(10:13):
worth noting, though, that during Trump's first urn, the administration
made moves to secure greater funding for planetary defense research,
and in its final days, it released a report looking
into America's asteroid impact emergency protocols, suggesting that planetary defense
is an issue that it sees as important. If Republicans

(10:36):
remain die hard fans of planetary defense, there is also
a chance that anti asteroid efforts will be accelerated over
the next four years. DART is a method of planetary
defense known as a kinetic impactor, partly autonomous spacecraft slims
into an asteroid just at the right speed and angle

(10:59):
to get onto a different orbit around the Sun, one
that doesn't terminate in a violent collision with Earth. Deflecting
an asteroid with something like dark clearly works well, but
if miscalculated and that asteroid is punched with too much oomph,
it could fracture the asteroid, turning an earth bound cannonball

(11:21):
into a shotgun spray of still lethal objects. But there
are many more methods of planetary defense, it's just that
for now they are purely conceptual. Take the gravity tractor,
for example, if you park a hefty spacecraft next to
an asteroid, you could potentially use that spacecraft's own gravity

(11:46):
to gradually pull the asteroid out of Earth's way. This
is a concept that's spoken about not just in planetary
defense circles, but in asteroid capture and mining discussions. Such
a program would require many years, perhaps decades, of work,
but it's a more precise, gentler method of planetary defense.

(12:08):
Some officials at NASA and those further AFFELD are keen
to try out alternative methods of planetary defense, including something
like a gravity tractor. Others, meanwhile, want to proceed with
dark IWO to impact other types of asteroids. Not all
of the objects have the same structure, size, or composition,

(12:29):
and some act more like boulders flying in formation than
anything rigid and monolithic. So these experts say we need
to deflect a variety of space rocks to see if
they all respond the same way to a kinetic impactor.
Planetary defense experiments are inherently imaginative, almost sci fi esque,

(12:52):
so the appeal to people of any political persuasion seems obvious,
particularly with how ingrained dangerous asteroids and its are in
our collective pop culture infused psyche. But conducting these space
based experiments also shores up humanity's ability to prevent a

(13:12):
cosmic catastrophe. In twenty twenty one, Lindley Johnson, who was
then the head of the NASA's Planetary Defense Coordination Office,
said during an interview quote, I think we've gotten the
planetary defense program at NASA now to about the right
level of resource and attention, before before adding our challenge

(13:33):
will be to keep it there. The hope back then
is the same as it is now, that no matter
who holds political power, NASA gets to keep looking up
and is granted the ability to protect the only home
we know. So let's turn now to an article from

(13:53):
National Geographic alarming levels of microplastics found in human brains.
This is from February three. Microplastics plastic particles fewer than
five millimeters in size have infiltrated the environment at an
alarming rate as worldwide plastic use increases. Levels of microplastics

(14:18):
found in the environment have surged in the past few decades,
with current plastic production at more than three hundred million
tons annually and an estimated two and a half million
tons floating in the world's oceans as of twenty twenty three,
over ten times the two thousand five level. A new

(14:42):
study in Nature Medicine finds that microplastics and nanoplastics, which
are even smaller at one to one thousand nanometers in size,
accumulate at higher levels in the human brain than in
the liver and kidneys. The study also finds significantly higher

(15:02):
concentrations of microplastics and nanoplastics in twenty twenty four samples
compared to twenty sixteen samples, and higher levels in brains
from people diagnosed with dementia. Although the study does not
establish a cause and effect relationship between these plastic particles

(15:23):
and dementia, it raises questions about the possible health consequences
of exposure to plastics. While scientists know these plastics are
in our bodies, how the impact our health is unclear. Quote.
We think this is simply mirroring the environmental build up
and exposure, says study author Matthew Kampen, professor of pharmaceutical

(15:47):
sciences at the University of Mexico. Quote, People are being
exposed to ever increasing levels of micro and nanoplastics In quote.
Micro and nanoplastics or abbreviated MNP, can be invisible to
the naked eye and come from larger plastic products like

(16:12):
soda bottles, shopping bags, and styrofoam containers breaking down in
the environment. Scientists have studied MNPs in the ocean since
the nineteen seventies. Marine animals have been found to have
microplastics in their bodies, absorbed from the water and from
eating contaminated fish. Microplastics also accumulate in the tissues of

(16:37):
other animals that people eat, like pigs, cows, and chickens.
MNPs can end up in the air too. Indoor air
especially tends to contain more MNPs than outdoor air due
to shedding of particles from plastics and clothing, furniture, and
household products. After we inhale these particles, they can try

(17:00):
travel through the body and end up in various organs.
Studies have found MNPs and human lungs, placentas, blood vessels,
and bone barrow. A twenty twenty four study found evidence
that MNPs can pass through the blood blood brain barrier,

(17:20):
a selective filter that controls what can enter the brain
from the bloodstream. While it was previously thought only the
smallest nanoplastics could pass the barrier, this study found larger
microplastics can enter the brain too. This study, published today
confirms the presence of MNPs in the brain and at

(17:42):
shocking levels. The study examined fifty two human brain samples
from twenty sixteen and twenty twenty four, all taken from
the frontal cortex, the part of the brain responsible for judgment,
decision making, and muscle movement. The researchers also looked at
livery kidney samples from the same bodies, analyzing all tissue

(18:04):
using microscope imaging and molecular analysis to identify the chemical composition.
Brain and liver samples from twenty twenty four had significantly
higher concentrations of MMPs compared with those from twenty sixteen.
The total mass of plastics in the brains that were

(18:27):
studied increased by about fifty percent between twenty sixteen and
twenty twenty four, and the researchers suggest drastically increasing concentrations
of MMPs in our homes, air and water could be
to blame. Quote. I am quite shocked by the amount
of microplastics they find, says Emma Castile, a neurotoxicologist at

(18:54):
Utrecht University in the Netherlands. It was a lot higher
than I would have expected. Growing levels of microplastics in
the environment are reflected in the new findings, says Castile,
with more exposure likely the cause of more plastic particles
in the organs. The brain samples overall had seven to

(19:17):
thirty times more MNPs compared with the liver and kidney samples.
Particles found in the brain were mostly tiny shards or
flakes of polyethylene, one of the most common plastics in
the world, often used in packaging. It makes sense that

(19:38):
MNPs accumulate more in the brain compared to other organs,
says Castile. Inhalation through the nose to what's called the
old factory bulb, the part of the brain that processes smell,
gives MNPs in the air a more direct route to
the brain than to other organs. Kempin points out the

(20:01):
age of the person was not associated with the amount
of plastic in the organs, meaning the body does clear
the plastic in some way. If not, older individuals, organs
would just continue to accumulate more and more plastic over
the years. Another notable finding was that MMP levels were
about three to five times higher in twelve brains from

(20:24):
people who had been diagnosed with dementia. The researchers clarify
this does not necessarily mean MMP's cause dementia, but it
shows an association that should be studied further. Castile says
the connection is likely because people with dementia tend to
have blood brain barriers that don't function as well as

(20:45):
a filter, meaning the high concentration of MMPs could be
a consequence of dementia rather than a cause. While scientists
don't fully understand the health impacts of MMPs in the brain.
They are calling for more research to better understand whether
they are harmful. Studies have shown MNPs in arteries can

(21:09):
be a risk factor for cardiovascular disease, and the cancer
cells in the stomach can spread faster after contact with MNPs.
More and more studies show that plastics are present in
the brain, including this new one, and they shouldn't be there,
says Castile. We don't know that much about the health effects,
but the fact is that they are there and they

(21:31):
shouldn't be there, and maybe that's worrying enough. Canpin's research
team wants to look at the whole brain next to
understand if there's more plastic accumulation in one specific area
and to see if that links to any specific health outcomes.
While there is no way to completely avoid exposure to plastics,

(21:53):
Castile says that on a personal level, there are small
choices you can make. The canrid use exposure, minimize single
use plastics, ventilating your home well and vacuuming regularly to
remove dust and plastic debris, and avoiding cosmetic products that
intentionally add MMPs, like scrubs with plastic beads. Scientists are

(22:18):
also developing solutions to reduce microplastics in the environment. There's
a type of worm that eats polystyrene and fungi and
microbes that break down plastics in the environment. Scientists are
developing new types of filters to remove MMPs from drinking water. Quote.

(22:40):
Plastic is everywhere. Most people cannot imagine a world without plastic.
Even if we stop producing plastic right now, the world
will still be full of microplastics, says Castele. So it's
good to think about mitigation measures, applying a precautionary principle
and seeing what we could do to minimize exposure to
maybe prevents certain health risks that there might be. And

(23:07):
now to USA today, these US cities they say growing
rat problem and scientists say they know why. This is
from February three. Scientists have some good news for rats
and some bad news for city dwellers. Rat populations are

(23:27):
rising in cities including Washington, d C. And San Francisco,
reports a study released Friday that includes data from sixteen
global cities. Primary among the reasons found for the growing
problem warmer average temperatures due to climate change, warmer winters,

(23:48):
denser living conditions, less vegetation, and limited rat control resources
also contributed to the growth in urban rat populations and
was most notable in Washington, d C. San Francisco, and
Toronto among the cities that were included in the study.
Quote most concerning of these connections we found is the

(24:11):
link between climate warming and rat trends, as global temperatures
are beyond the control of individual cities, said study lead
author Jonathan Richardson. He's from the University of Richmond. According
to the research, rats tendency to infiltrate buildings and spoil
supplies can cause billions of dollars of damage to cities

(24:34):
where they live in the highest numbers. According to Richardson,
while there aren't good studies on how wild rats respond
to temperature changes, we do expect that the warmer temperatures,
particularly during the colder times of the year, will increase
the time rats spend above ground foraging for food. An

(24:55):
extra week or two of foraging can result in one
or two more reproductive st cycles, accelerating population growth, he said. Overall,
the study found that increases in average temperature, winter temperature,
and living density, alongside decreases in vegetation and funding for
rat control, correlates with faster urban rat expansion of these

(25:19):
The variable most tightly tied to rat increase was change
in average ambient temperature over time. Quote. Cities need to
be prepared for the potential for climate warming to exacerbate
current rodent pest infestation levels. More financial and personal resources

(25:40):
will need to be dedicated to municipal rodent control efforts.
The study said which city had the highest rat growth rate? Washington,
d C has the fastest growth in rats of all
the cities in the study. Richardson said. After Washington, the

(26:00):
next four cities with fastest growth rates include San Francisco, Toronto,
New York City, and Amsterdam. Within these top five, the
researchers saw large differences in the magnitude of that growth.
For example, Washington, DC had one and a half times
greater growth in rat populations than New York City. Unfortunately,

(26:22):
we don't have the data necessary to estimate raw abundance
of rats in these cities, just trends in the changes,
he told USA Today. Researchers analyzed and average of about
twelve years of rat sightings, trapping reports, and inspection records
from sixteen international cities and compare the data to patterns

(26:46):
in human density. Annual minimum temperatures and average ambient temperatures
over time. They also compared rat population changes with trends
in vegetation abundance and accessibility to rat control resources. The
study found that eleven of sixteen cities, sixty nine percent

(27:07):
had significant increasing trends in rat numbers. Only by confronting
the environmental factors that allow rats to thrive and by
giving municipal rodent managers the resources and tools they need,
can we hope to bin in a growing rat problem.
Richardson said. The study was published Friday in the peer

(27:28):
reviewed journal Science Advances, a publication of the American Association
for the Advancement of Science. Well, that will be all
for today's a Diary of Science and Nature. Your reader
was Kelly Taylor. Thanks for listening, and now you can

(27:49):
stay tuned for the Health Corner on RADIOI