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NNadir

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Greenhouse Gas and Health Benefits of Electric Vehicles on a Heavily Nuclearized Grid.

The paper I'll discuss in this post is this one: Health and Climate Incentives for the Deployment of Cleaner On-Road Vehicle Technologies (Laura Minet, An Wang, and Marianne Hatzopoulou Environmental Science & Technology 2021 55 (10), 6602-6612)

Many people question how I can simultaneously be an opponent of the electric car fantasy while also being an advocate of nuclear energy. This is because most people - and many nuclear energy advocates do engage in the greenwashing of electric cars - think of nuclear energy primarily as a tool for generating electricity. A conservative is, of course, a person who believes that everything should remain as it is and has been and that nothing should be tried for the first time, and thus the belief that electricity is the only possible product of nuclear energy is a conservative idea, and thus, as the world environment rapidly deteriorates at an accelerating pace, this belief is a dangerous idea.

I insist that electric cars are not sustainable for the same reason that so called "renewable energy" is not sustainable, specifically because of the high mineral mass requirement. (The IEA recently published several reports on this issue, which is slowly leaching into a conscious reality for anyone who is paying attention, albeit this with the understanding that lying to oneself is much easier than paying attention, and thus paying attention is not widely practiced.)

Nevertheless I found the paper cited at the outset to be quite interesting, not because I approve of electric cars, but because it emphasizes the reason that, despite all the attention paid to Chernobyl and Fukushima by the easily misled, nuclear energy, overall, saves lives; to wit: By the prevention of air pollution.

An electric car running in a area powered by dangerous fossil fuels - I discussed a paper in this same journal on the subject of electric vehicles in China (where there are 100 million such vehicles, albeit mostly scooters) - is merely a device for generating more pollution while wasting energy.

This study however discusses the Toronto, Canada area. Before excerpting anything connected with other aspects of the paper, before even excerpting the paper's introduction, let me excerpt this text about the generation of electricity on the grid serving Toronto as of 2016.

Under scenarios S1 and S2, the production of the electricity fueling the EVs and BEBs follows the 2016 average grid mix of Ontario, which is 9% natural gas, 61% nuclear, 24% hydro, and 6% wind.(22)


Only 9% of the grid depends on dangerous fossil fuels, and that is probably connected with backup of the largely useless and environmentally unacceptable wind industry. (I'm not particularly fond of hydroelectricity either; I'm a free river kind of guy.)

An "EV" is of course, an electric car, a "BEB" is a "battery electric bus."

The graphic at the outset the paper, which is available merely by clicking on the link above, which will give the abstract lays it out in terms of lives saved from air pollution, which now is killing about 7 million people per year while people carry on about Fukushima.

Here it is:



The nuclear infrastructure in Canada is almost entirely CANDU reactors, heavy water reactors, designed to run on unenriched uranium, albeit at low burn-ups. The burn-ups of CANDUs could, in theory, be extremely high, were they fueled on a ternary mixture of plutonium, depleted (or natural) uranium and thorium, or by uranium recovered from so called "nuclear waste" and thorium, and other approaches, mostly being explored in India, which also relies on heavy water reactors for clean nuclear energy.

Although a CANDU is basically a device only useful for generating electricity, I am still very fond of this reactor type and I wish we had a lot of them in the US, but we don't. They can in theory run for a very long time on the uranium component of so called "nuclear waste" in a cycle known as the "DUPIC" cycle, with the added benefit of producing significant neptunium for anti-proliferation purposes.

Anyway.

From the introductory text of the paper:

In Canada, in 2017, the transportation sector was the second largest source of greenhouse gas (GHG) emissions(1) and an important contributor to air pollutant emissions.(2) Since one-third of the Canadian population lives in close vicinity to major roads (i.e., within 250 m), air pollutant emissions from the transportation sector have considerable health impacts: several Canadian studies have associated increased exposure to air pollution with increased risks of cancers, circulatory and respiratory diseases, and mortality.(3−7)

Light- and heavy-duty vehicles and transit buses constitute the majority of the on-road vehicle fleet in Canada.(8) Different approaches can be adopted to tackle their impacts on population exposure and health. Traffic management strategies (TMSs), such as congestion pricing, low emission zones, truck/bus lanes, or transit improvement, can be implemented. However, the use of TMS for improving ambient air quality is not always efficient because they can be counterbalanced by indirect effects (e.g., increased traffic volumes induced by congestion mitigation strategies and traffic diversion to different areas as a result of tolling and restrictions).(9) Therefore, such initiatives should be complemented by tackling the emissions at the source through a replacement of the existing fleet by lower-emitting vehicles. For private passenger vehicles (i.e., cars and SUVs owned by private households) and transit buses, vehicle electrification is often seen as an opportunity to decrease GHG emissions, and since electric vehicles (EVs) and battery electric buses (BEBs) do not generate exhaust emissions, electrification has also been promoted to reduce traffic-related air pollution, especially in regions with relatively clean electricity production.(10−13) For commercial vehicles (i.e., light-duty and heavy-duty), Pan et al.(14) highlighted that eliminating high-emitting trucks would bring substantial improvements in population exposure and health.
There are only few studies comparing the co-benefits of GHG mitigation strategies targeting all three fleets of vehicles. In India, Dhar and Shukla(15) quantified the changes of air pollutant emissions resulting from different policies involving sustainable technologies, fuels, and logistics for private cars, transit buses, and commercial vehicles. However, they did not quantify the implications on air quality, population exposure, and health. In the U.K., Smith et al.(16) analyzed the co-benefits and conflicts associated with measures aiming for a reduction of the carbon budget of the country, but the strategies incorporated in the scenario studied were broad and encompassed measures that went beyond improvements of vehicle fleets.

In this study, we applied an integrated framework combining a traffic assignment model with an air quality model to evaluate the health implications of a series of transportation scenarios designed by a panel of sustainable transportation experts in the context of the Greater Toronto and Hamilton Area (GTHA), the largest metropolitan area of Canada...


The methods utilized by the authors:

...After designing different study cases and transportation scenarios (2.1), we developed emission inventories for private passenger vehicles, transit buses, and commercial vehicles, which we then modified to reflect the transportation scenarios outlined (2.2). Then, we set up a chemical transport model (CTM) over the GTHA to quantify the air quality impacts under the study cases and scenarios (2.2). Finally, we estimated the exposure of the population and conducted an assessment of the health outcomes and social benefits associated with the scenarios (2.3)...


The scenarios:


...Scenario 1 (S1—100% EV) assumes an electrification of the private passenger vehicle fleet;

Scenario 2 (S2—100% BEB) assumes an electrification of the transit bus fleet;

Scenario 3 (S3—cleaner trucks) assumes that trucks older than 8 years have recently been renewed. The rationale behind this choice is that most scrappage programs are for vehicles of that age; few target trucks, but those for private passenger vehicles implemented in Europe are usually applicable for vehicles older than 8–10.(20,21)...


Some graphics describing their findings:



The caption:

Figure 1. Comparison of the NOx, BC, and fuel-cycle GHG emissions from private passenger vehicles, commercial vehicles, transit buses, and electricity for EVs and BEBs under the base case and the different scenarios for a typical weekday: (a) total daily emissions and (b) percent contribution of each mode.




The caption:

Figure 2. Comparison of the annual health outcomes associated with each vehicle category and each scenario (each outcome related to the three vehicle categories indicates a burden, while the outcomes related to the scenarios indicate benefits). The uncertainty bars represent the interquartile range resulting from the use of a range of odds ratios associated with each pollutant and health outcome (indicated in parentheses in the legend).




The caption:

Figure 3. Distribution by region of (a) the social costs and fuel-cycle GHG emissions associated with each vehicle category and (b) the social benefits and fuel-cycle GHG emission savings obtained under each scenario. These figures are based on average numbers of premature deaths extracted from the uncertainty analysis of the health outcome assessment.




The caption:

Figure 4. Spatial distribution of years of life saved per 100,000 capita under each scenario. These figures are based on the average number of years of life saved extracted from the uncertainty analysis of the health outcome assessment.


Discussing the lives saved (or in this case potentially saved) by nuclear energy is not as sexy as getting a wedgie in one's underwear worrying about critical zones in the wreckage of the Chernobyl reactor, but if we were serious - and we're not, as we hit 420 ppm of CO2 in the planetary atmosphere this year while literally Quixotically genuflecting endlessly at wind turbines - it would matter that overall, nuclear energy saves lives.

In the conclusion the authors, in a clear burst of honesty reflecting the (huge) caveat write this:

...Finally, GHG emissions do not account for upstream impacts from battery manufacturing. Ma et al.(56) estimated life-cycle GHG emissions of internal combustion engine vehicles and EVs to be about 38.1 and 54.5 g of CO2 equiv/km, respectively. Using these numbers, we estimated that GHG emission savings under the EV scenarios are decreased by about 8%.

To conclude, this analysis highlights the necessity to tackle the emissions from all categories of vehicles: private passenger vehicles because they are important sources of GHG emissions and responsible for substantial social costs related to air pollution exposure; commercial vehicles because they are responsible for more than half of the YLL and premature deaths attributed to traffic-related air pollution exposure in the GTHA; and transit buses because they are operating in densely populated areas and their emissions have therefore higher health impacts in proportion.


I have added the bold in the above excerpt.

I don't know if this will inspire anyone to light a candle in one of the many temples for worshipping Elon Musk. I have no use for the guy, but feel free to do so if so inspired by this interesting paper.

I hope you will have a pleasant and safe day tomorrow.

A little Godwin type history.

Hitler destroyed the Weimar democracy using means that we're legal under the Weimar constitution.

The White Supremacy Party, misidentified as the "Republican" Party, like the consumate racist preceeding them, are now engaged in a similar effort to destroy and overthrow the American democracy, the same way, legal obstructions and overt lies.

History will surely judge McConnell, Trump and Putin as they succeed in destroying country severely, but frankly, Hitler himself was unaffected by his historic reputation.

This is an old playback, and they're using it.

First nuclear detonation created 'impossible' quasicrystals

A news item from Nature, it's probably open sourced:

First nuclear detonation created ‘impossible’ quasicrystals

Their structures were once controversial. Now researchers have discovered quasicrystals in the aftermath of a 1945 bomb test.


Davide Castelvecchi, Nature News, May 17, 2021



This sample of red trinitite was found to contain a previously unknown type of quasicrystal.Credit: Luca Bindi, Paul J. Steinhardt


Excerpts:

Scientists searching for quasicrystals — so-called ‘impossible’ materials with unusual, non-repeating structures — have identified one in remnants of the world’s first nuclear bomb test.

The previously unknown structure, made of iron, silicon, copper and calcium, probably formed from the fusion of vapourized desert sand and copper cables. Similar materials have been synthesized in the laboratory and identified in meteorites, but this one, described in Proceedings of the National Academy of Sciences on 17 May, is the first example of a quasicrystal with this combination of elements1.

Impossible symmetries

Quasicrystals contain building blocks of atoms that — unlike those in ordinary crystals — do not repeat in a regular, brickwork-like pattern. Whereas ordinary crystal structures look identical after being translated in certain directions, quasicrystals have symmetries that were once considered impossible: for example, some have pentagonal symmetry, and so look the same if rotated by one-fifth of a full twist.

Materials scientist Daniel Shechtman, now at the Technion Israel Institute of Technology in Haifa, first discovered such an impossible symmetry in a synthetic alloy in 1982. It had pentagonal symmetry when rotated in each of various possible directions, something that would occur if its building blocks were icosahedral — that is, had a regular shape with 20 faces. Many researchers initially questioned Shechtman’s findings, because it is mathematically impossible to fill space using only icosahedrons. Shechtman ultimately won the 2011 Nobel Prize in Chemistry for the discovery.

At around the same time, Paul Steinhardt, a theoretical physicist now at Princeton University in New Jersey, and his collaborators had begun to theorize the possible existence of non-repeating 3D structures. These had the same symmetry as an icosahedron, but were assembled from building blocks of several different types, which never repeated in the same pattern — thus explaining why the mathematics of symmetrical crystals had missed them...

...‘Slicing and dicing’

In the aftermath of the Trinity test — the first ever detonation of a nuclear bomb, which took place on 16 July 1945 at New Mexico’s Alamogordo Bombing Range — researchers found a vast field of greenish glassy material that had formed from the liquefaction of desert sand. They dubbed this trinitite.

The plutonium bomb had been detonated on top of a 30-metre-high tower, which was laden with sensors and their cables. As a result, some of the trinitite that formed had reddish inclusions, says Steinhardt. “It was a fusion of natural material with copper from the transmission lines.” Quasicrystals often form from elements that would not normally combine, so Steinhardt and his colleagues thought samples of the red trinitite would be a good place to look for quasicrystals .

“Over the course of ten months, we were slicing and dicing, looking at all sorts of minerals,” Steinhardt says. “Finally, we found a tiny grain.” The quasicrystal has the same kind of icosahedral symmetry as the one in Shechtman’s original discovery.

Cardiac Muscle Patches Engineered w/Human Induced-Pluripotent Stem Cell Improve Infarct Recovery.

The paper to which I'll point in this brief post: Large Cardiac Muscle Patches Engineered From Human Induced-Pluripotent Stem Cell–Derived Cardiac Cells Improve Recovery From Myocardial Infarction in Swine (Ling Gao, Zachery R. Gregorich, Wuqiang Zhu, Saidulu Mattapally, Yasin Oduk, Xi Lou, Ramaswamy Kannappan, Anton V. Borovjagin, Gregory P. Walcott, Andrew E. Pollard, Vladimir G. Fast, Xinyang Hu, Steven G. Lloyd, Ying Ge, and Jianyi Zhang Cirulation 2018;137:1712–1730)

This week it was my privilege to attend an online lecture By Dr. Ying Ge, of the University of Wisconsin. I was drawn to the lecture because of her use of a Bruker 15 Tesla FT-ICR mass spec, and the related Bruker TIMS-TOF instrument. (The lecture was sponsored by Bruker.) Before the lecture, I fully confess to being unfamiliar with her work; but I am actively familiarizing myself with it now.

I have seen, probably, hundreds, if not thousands of lectures on mass spec, and I'm sure I'll always place this one near the top, comparable to a lecture some years ago in the same forum by Dr. Richard Caprioli during which, among neat tricks, he showed imagines based on the proteome of a whole mouse, and discussed the proteome of a person who died around the time of the American Civil war.

In Dr. Ge's lecture, she discussed the creation of human heart muscle tissue, generated by culturing human stem cells derived from human blood, and culturing them so as to produce human heart muscle, which was then implanted into pigs (which have a proteome in many ways the closest to human) which had induced cardiac infartions, heart attacks.

The lecture included a short video of the generated tissue beating like a human heart.

The guts of Dr. Ge's paper, again available on line, but the abstract covers what the whole thing is about.

Abstract

Background:

Here, we generated human cardiac muscle patches (hCMPs) of clinically relevant dimensions (4 cm × 2 cm × 1.25 mm) by suspending cardiomyocytes, smooth muscle cells, and endothelial cells that had been differentiated from human induced-pluripotent stem cells in a fibrin scaffold and then culturing the construct on a dynamic (rocking) platform.

Methods:

In vitro assessments of hCMPs suggest maturation in response to dynamic culture stimulation. In vivo assessments were conducted in a porcine model of myocardial infarction (MI). Animal groups included: MI hearts treated with 2 hCMPs (MI+hCMP, n=13), MI hearts treated with 2 cell-free open fibrin patches (n=14), or MI hearts with neither experimental patch (n=15); a fourth group of animals underwent sham surgery (Sham, n=8). Cardiac function and infarct size were evaluated by MRI, arrhythmia incidence by implanted loop recorders, and the engraftment rate by calculation of quantitative polymerase chain reaction measurements of expression of the human Y chromosome. Additional studies examined the myocardial protein expression profile changes and potential mechanisms of action that related to exosomes from the cell patch.

Results:

The hCMPs began to beat synchronously within 1 day of fabrication, and after 7 days of dynamic culture stimulation, in vitro assessments indicated the mechanisms related to the improvements in electronic mechanical coupling, calcium-handling, and force generation, suggesting a maturation process during the dynamic culture. The engraftment rate was 10.9±1.8% at 4 weeks after the transplantation. The hCMP transplantation was associated with significant improvements in left ventricular function, infarct size, myocardial wall stress, myocardial hypertrophy, and reduced apoptosis in the periscar boarder zone myocardium. hCMP transplantation also reversed some MI-associated changes in sarcomeric regulatory protein phosphorylation. The exosomes released from the hCMP appeared to have cytoprotective properties that improved cardiomyocyte survival.

Conclusions:
We have fabricated a clinically relevant size of hCMP with trilineage cardiac cells derived from human induced-pluripotent stem cells. The hCMP matures in vitro during 7 days of dynamic culture. Transplantation of this type of hCMP results in significantly reduced infarct size and improvements in cardiac function that are associated with reduction in left ventricular wall stress. The hCMP treatment is not associated with significant changes in arrhythmogenicity.


My point here is that Dr. Ge is clearly an immigrant, as are clearly some of her students, a function of China sending us some of her best and brightest to enlighten and raise us up out of the dregs of ignorance.

There are zero members among the 50 members of the White Supremacist Party in the United States Senate, and Zero members of that same party in the Congress who are her intellectual equal.

Zero.

Not the child molester from Florida and his idiot gun toting racist apologist with whom he travels while she rambles about Jewish space lasers, not Kevin the Klansman, the insurrectionist Minority Leader, not Moscow Mitch, none of them.

Let me say that again: Zero.

They are all, 100% of these white people in the US Congress in the White Supremacist Party, and their token African American from South Carolina, who would be qualified to wash glassware in her lab.

Just saying, in anger...

It just occurred to me who the President who did the most to fight Covid was.

That would be Bill Clinton.

By pushing the human genome project and publicly funding it, he helped to improve the speed of genomic sequencing, and build a huge infrastructure around it.

Now we can sequence just about any living thing, from flies, to apes, to hippopotamuses to viruses.

It was public funding of science at its best.

If you get a vaccine, thank Bill.

Plutonium-244 Discovered on the Ocean Floor Constrain the Yields of Recent Local Supernovae.

The paper I'll discuss in this post is this one: 60Fe and 244Pu deposited on Earth constrain the r-process yields of recent nearby supernovae (Wallner et al., Science, 14 May 2021: Vol. 372, Issue 6543, pp. 742-745)

Not so long ago in this space, I referred to the campaign taking many years to produce the world supply, 7 grams, of the very long lived isotope of plutonium, Pu-244: Recovery of Trivalent Lanthanides and Transplutonium Actinides with Resin Supported Diglycomides. This rare isotope has a half-life of 81.1 million years, making it useful as an internal standard in nuclear forensics, as a target for the synthesis of the super-heavy elements, and for the study of chemical properties of the element, while minimizing occlusive effects associated with the higher radioactivity of isotopes with a longer half life. Very little Pu-244 is formed in commercial nuclear reactors, nor were large amounts formed in the era of nuclear testing. Early reports indicated that Am-244 had a branch ratio by which a tiny amount, on the order of 1 decay in 1000, decayed by electron capture to give Pu-244, but when I went to the latest data tables at the Brookhaven National Laboratory's Nuclear Data pages, it is now reported that this isotope actually decays 100% by β- to give Cm-244. This means that the only path to the creation of Pu-244 relies in neutron capture in Pu-243, an isotope with a short half-life, about 5 hours, or by the decay of Cm-248, which can only be produced with very long irradiation times, and in any case, has a long lifetime - its half-life is 348,000 years - precluding it's use as a Pu-244 source. Although I do not know whether the fission cross section or capture cross sections of Pu-243 are known, as a nuclei with an odd mass number and an even atomic number, the fission to capture ratio is likely to be fairly high. Nevertheless, it is possible, as it was in historical high flux research nuclear reactors, to produce rather small amounts of this isotope. (It is also believed that small amounts of Pu-244 may have been formed in historic open air hydrogen bomb tests, which produce high neutron fluxes, but the isotope has not been detected in fall out to my knowledge.)

The situation is quite different in collapsing stars, supernovae, where the neutron flux can easily dwarf anything that can be generated on Earth, as well as during collisions between neutron stars. The collapse of these stars has produced all of the uranium and thorium, the billions of tons of each, that now drives the internal heat of the Earth (with a minor assist from radioactive potassium-40). This takes place during the "r-process" in which nuclei absorb neutrons faster than they can decay by beta emission, thus producing very heavy nuclei up to an including fermium, and perhaps even higher. As a result, much of the thorium-232, the isotope that dominates all of Earth's thorium, may be the decay product of Pu-244 and/or it's precursor, Cm-248.

The long half-life of Pu-244 suggests that may have survived long enough to have accreted in the early Earth, and it believed that an isotope of the xenon present in the Earth's atmosphere may have been formed by spontaneous fission of this historic Pu-244. One can calculate that 1 kg of Pu-244 in the early Earth would leave behind about 48 million atoms after 4.5 billion years.

In 1971, the great nuclear chemist Darleane Hoffman reported that she had discovered a few atoms of Pu-244 in lanthanide ores at the Mountain Pass mine, after reasoning that the geochemistry of plutonium should be very similar to that of cerium and thorium, both of which are constituents of these ores. (Thorium is a by product of the lanthanide ("rare earth" ) mining on which so called "renewable energy" and many other technologies depend. If recovered from mine tailings, this thorium could in theory replace all mining for energy purposes for many hundreds of years.) Her report, which has not been confirmed by the use of accelerator mass spec, is here: Detection of Plutonium-244 in Nature (D. C. Hoffman, F. O. Lawrence, J. L. Mewherter & F. M. Rourke, Nature volume 234, pages132–134 (1971))

The paper cited at the outset refers to Pu-244 that is believed to have rained down on Earth in recent times as a result of supernovae that took place near our solar system in the last tens of millions of years.

The abstract is open sourced. From the introduction to the paper itself:

All naturally occurring nuclides heavier than iron are produced in stellar environments, almost exclusively by nuclear processes involving the successive captures of neutrons to build up heavier masses. About half of these nuclides are synthesized slowly as a by-product of steady stellar fusion. The other half, including all actinide elements, require a very short but intense flux of neutrons, resulting in a rapid neutron capture process (r-process). The sites and yields of the r-process remain a topic of debate (1–6). It is expected to occur in explosive stellar environments such as certain types of supernovae (SNe) or neutron-star mergers (NSMs), the latter of which has been supported by observations of the gravitational-wave event GW170817 (7). The abundance patterns of r-process nuclides can be used to constrain the production site. Radioactive isotopes (radionuclides) provide additional time information resulting from their decay over time following their synthesis. Such radionuclides should be scattered through the interstellar medium (ISM) and could be deposited on Earth.

The Solar System (SS) is located inside a large ISM structure [the Local Superbubble (LB)] that was shaped by supernova (SN) explosions during the last ~12 million years (Myr) (8). Earth has therefore been exposed to both ejecta from the SNe and swept-up interstellar material that traversed the SS during this time period (9, 10). Dust particles from the ISM pass through the SS (11) and contain nucleosynthetic products of stellar events (e.g., stellar winds and SNe) (10, 12, 13). Earth’s initial abundance of the 60Fe radionuclide [half-life (t1/2) = 2.6 Myr (14, 15)] has decayed to extinction over the 4.6 billion years (Gyr) since the SS’s formation. 60Fe, however, is produced in massive stars and ejected in SN explosions. Evidence for the deposition of extraterrestrial 60Fe on Earth has been found in deep-sea geological archives dated to between 1.7 and 3.2 million years ago (Ma) (16–20), at recent times (21, 22), and possibly also around 7 Ma (19). 60Fe has also been detected in lunar samples (23), in astronomical observations of gamma rays associated with its radioactive decay (24), and in galactic cosmic rays (25). SN activity in the last ~2 Myr is suggested by an excess in the local cosmic-ray spectrum (26). Other radionuclides are also produced and ejected in such explosions (9, 27–30). If substantial r-process nuclei are produced in SNe this would also have enriched the local ISM with actinides, such as 244Pu. With a half-life of 80.6 Myr, 244Pu is much longer lived than 60Fe, so it can be contributed by older r-process events, not limited to those that formed the LB. Either as part of the SN direct ejecta or as continuous ISM influx, we expect dust particles containing 244Pu to enter the SS, similarly to 60Fe, but probing different nucleosynthetic processes. Previous measurements in terrestrial or lunar archives have provided only upper limits on actinide influx (12, 31–33).

We searched for extraterrestrial 60Fe and 244Pu incorporated into a deep-sea sample on Earth—a ferromanganese crust (which we refer to as Crust-3) that spans the last 10 Myr, sampled at ~1500 m below sea level in the Pacific Ocean, with 115-cm2 cross-sectional area and ~25-mm thickness (27). The radionuclides were identified and counted using accelerator mass spectrometry (AMS) (27). For 60Fe, a time-resolved depth profile of ~1-cm2 area was analyzed, subdivided into 24 layers, each ~1-mm thick, corresponding to a time resolution of ~0.4 Myr per layer [crust growth-rate of ~2.4 mm Myr−1, dated with terrestrial 10Be (27)]. The remaining part of Crust-3 (114-cm2 area), after separating the aliquots used for 60Fe analysis, was split into three thick, horizontal layers designated 3/A (extending from 0 to 3 mm, equivalent to 0 to 1.3 Ma, with a mass of ~20 g), 3/B (3 to 10 mm, 1.3 to 4.6 Ma, 179 g), and 3/C (10 to 20 mm, 4.6 to 9.0 Ma, 208 g), given the anticipated low abundance of 244Pu. We expected the top layer to contain anthropogenic Pu from atmospheric nuclear weapons tests performed during the 20th century...


Radioactive iron-60 is also formed in nuclear weapons tests, from neutron capture in the steel casings, and it can also be formed in small amounts in commercial nuclear reactors having steel cores - this accounts for Co-60 in pressurized water and boiling water reactors. However, in sediments, the age of the sediments can be determined by examining the Co-60/Fe-60 ratio or the ratio of Ni-60, the final stable decay product. The authors here took other steps to differentiate the age of their sediments to differentiate them from nuclear weapons testing contamination. They used beryllium-10, the radioactive isotope that forms naturally in the Earth's atmosphere by spallation from oxygen and nitrogen interacting with cosmic rays.

They detected 435 atoms of Fe-60 in their samples.

Table 1 from the paper:



The caption to table 1:

ble 1 60Fe/Fe ratios from AMS measurements of layered samples of Crust-3.
Twenty-four individual samples, distributed equally across 10 Myr, were analyzed and combined into four sections (individual data are listed in table S1). The stable Fe content was measured separately through inductively coupled plasma mass spectrometry (ICP-MS) (table S4). Ages are derived from 10Be measurements (table S5) and have an uncertainty of ±0.3 Myr (27).The number of 60Fe background events expected was calculated by scaling (in measurement time and beam intensity) measurements of terrestrial Fe blank samples. 60Fe/Fed.c. denotes background- and decay-corrected data (27). Dashes in otherwise empty cells indicate not applicable.


They were also able to differentiate Pu-244 of extraterrestrial origin from nuclear testing contamination by determining the ratios of Pu-244 to its decay product Pu-240 and the presence or absence of Pu-239, Pu-241 (and its decay product Am-241), Pu-242:

We observed an anthropogenic Pu signal in the top layer of Crust-3, which has 240Pu/239Pu and 241Pu/239Pu isotope ratios that are consistent with the expected values for nuclear weapons fallout (supplementary text). 239Pu, 240Pu, and 244Pu events were observed in all three crust layers, and 241Pu was observed in the first two layers. The 240Pu/239Pu and 241Pu/239Pu ratios are constant over these layers. The 244Pu/239Pu ratio shows an excess over anthropogenic levels in the two deeper layers (Fig. 2 and fig. S4). Assuming that the 244Pu abundance is dominated by the anthropogenic contribution in the top layer, we correct the deeper layers for this contribution and attribute the additional 244Pu to extraterrestrial deposition. The amount of short-lived anthropogenic Pu in the deeper layers indicates some anthropogenic Pu penetrated below the top layer (with concentrations relative to the top layer A of 1.5 and 0.1% in layers B and C, respectively), possibly as a result of pore water–induced redistribution into the deeper layers (27). If 60Fe also migrates in crusts, our observed time profile (Fig. 1A) could have been slightly broadened by this effect.


Pictures from the text:



The caption:

Fig. 1 Influx of interstellar 60Fe and 244Pu.
(A) 60Fe incorporation rates for Crust-3. The data (red points) have been decay corrected, and each layer is equivalent to 400 thousand years. The absolute ages have an uncertainty of ~0.3 to 0.5 Myr (27). (B) 244Pu incorporation rates for the three layers after subtraction of the anthropogenic 244Pu fraction (27). (C) 244PuISM/60Fe number ratio in the crust sample with layers 1 and 2 combined (horizontal solid lines with shaded error bars). All error bars show 1σ Poisson statistics.




The caption:

Fig. 2 Measured Pu isotope ratios and comparison with global fallout values.
(A and B) Variations of the measured 240Pu/239Pu ratio (A) and the 244Pu/239Pu ratio (B) across the three layers (solid red lines). The dashed red lines and gray shading indicate 1σ uncertainties. The blue shaded area and solid line represent the expected ratios for Pu from nuclear weapons fallout (27). 240Pu/239Pu remains constant across the three layers, whereas 244Pu/239Pu is enhanced in the deeper (older) layers. We attribute the excess above anthropogenic (anthr) levels to extraterrestrial 244Pu. Equivalent data for 241Pu/239Pu are shown in fig.


Table 2 from the paper:




The caption to Table 2:

Table 2 60Fe and 244Pu data for three time periods during the last 10 Myr from three crust layers.
Crust-3 data are from this work, and Crust-0 data are from (12, 19). For details on the ISM (extraterrestrial) flux and fluence calculations, see (27). The FeMn-crust sample was split into three layers A, B, and C for 244Pu (18, 179, and 208 g, respectively). The individual 60Fe data (background-corrected) from table S1 were combined to cover the same time periods as 244Pu. All uncertainties are 1σ [we converted the 2σ values for Crust-0 (12) to 1σ]. The bolded lines (Crust-30-4.6 and Crust-00.5-5.0) cover the time periods of the younger 60Fe influx (0 to 4.6 Ma and 0.5 to 5.0 Ma, respectively). The italicized lines (Crust-30-9.0 and Crust-00.5-12) represent the time integral over the 9 Myr covered by Crust-3 as well as the similar time span of 0.5 to 12 Ma investigated for Crust-0 (12). Dashes in otherwise empty cells indicate not applicable.


From the conclusion to the paper:

...Our measurements of extraterrestrial 244Pu and 60Fe confirm an influx of interstellar material into the inner SS through two or more local and transient SN events over the last ~10 Myr, and they are compatible with some production of actinides in core-collapse SNe, possibly of common type. Combining these data with previous results of 244Pu influx over the past 25 Myr (12) (extending prior to the formation of the LB) indicates that SN actinide yields seem insufficient to account for the overall abundance of r-process nuclides in the Galaxy (fig. S8). These yields can be compared with the total r-process inventory calculated by SN actinide nucleosynthesis simulations, which, however, is limited by model uncertainties. The present data are compatible with the LB being a local disturbance of a large-scale Galactic steady-state (from SN enrichment of the ISM occurring more frequently than the radioactive half-life), with less-frequent injections from rarer r-process sources that nevertheless dominate the production of r-process elements, such as NSMs. The data are also consistent with the hypothesis of a nearby rare event before the time of SS formation that supplied the majority of the SS known inventory of the primordial actinides Th, U, and Pu (12, 38) (fig. S9 and supplementary text).


Esoteric, but cool, I think.

Have a great and safe weekend.


Reduced neutralization of SARS-CoV-2 B.1.1.7 variant by convalescent and vaccine sera

Before citing this paper, let me start with the "Do not panic button, by excerpting the study's limitations from the end of the paper.

To wit:

Limitations of the study

The correlates of protection from SARS-CoV-2 infection are yet to be established. The in vitro neutralization assays reported here do not convey the contributions to in vivo protection provided by T cells nor the contributions of Fcγ receptor interactions and complement activation. Convalescent plasma and vaccine serum were taken relatively soon after acute illness or following vaccination; it is possible that titers will drop over time to a point where they are no longer high enough to provide protection. It will be interesting to understand the antibody response made by people infected by B.1.1.7, particularly how antibodies adapt to the N501Y change, but also the deletions occurring in the NTD. It will also be instructive to look at how well convalescent or vaccine serum can neutralize the other recently described variants B.1.351 and P.1 and, conversely, how well serum from patients infected with these variants can neutralize B.1.1.7 and the original Wuhan strains.


I have added the bold.

The paper under discussion is this one: Reduced neutralization of SARS-CoV-2 B.1.1.7 variant by convalescent and vaccine sera (Mongkolsapaya, Stuart, Screaton et al., Cell VOLUME 184, ISSUE 8, P2201-2211.E7, APRIL 15, 2021)

This article is open sourced, and anyone can read it, so I'll just excerpt a few things, and show, for convenience, a few graphics.

From the introduction:

Since its first appearance in Wuhan in December 2019, SARS-CoV-2 rapidly spread around the world leading the WHO to declare a pandemic on March 11, 2020. Since then, drastic public health measures, including draconian lockdowns with severe economic cost, have been enacted to contain virus spread. Although initially successful at containing disease, many countries are now experiencing further waves of infection, coinciding with winter in the northern hemisphere, with infections in some countries outpacing those seen during the first wave (Kröger and Schlickeiser, 2021).
Huge strides have been made in the understanding of SARS-CoV-2 over the last year, which are exemplified by the licensing of several vaccines (in the UK those made by Pfizer-BioNtech, Moderna, and Oxford-AstraZeneca), which are being rolled out in massive global vaccination programs, with the aim to reach billions of individuals in 2021. Furthermore, Janssen and Novavax have recently reported results showing good efficacy and also report efficacy against the UK B.1.1.7 strain (https://blogs.sciencemag.org/pipeline/archives/2021/01/29/jj-and-novavax-data). In parallel, a number of potently neutralizing monoclonal antibodies (mAbs) have been developed that are in late-stage trials to be used prophylactically or therapeutically (Baum et al., 2020, Yang et al., 2020).

SARS-CoV-2 is a large positive-stranded RNA virus; the major virion surface glycoprotein is the trimeric spike that attaches the virus to host cells via the ACE2 receptor and, through a series of conformational changes, allows fusion of host and virion membranes releasing the virus RNA into the cell to start the infection cycle (Hoffmann et al., 2020; Ou et al., 2020). Spike is the target of RNA (Polack et al., 2020; Baden et al., 2021), viral vectored (Voysey et al., 2021), and inactivated virus and recombinant protein-based vaccines (Yadav et al., 2020).

Because of the huge number of genome replications that occur in infected populations and error-prone replication, viral mutations do and will continue to occur (Robson et al., 2020). Although the vast majority will be inconsequential or detrimental to viral fitness, a few may give the virus a competitive advantage and be the subject of rapid natural selection relating to transmission advantage, including enhanced replication and immune evasion. This leads to the emergence of dominant new variant viruses. Coronaviruses, as we are seeing with COVID-19, have the potential to alter their proteins with dramatic effect (Denison et al., 2011).

In recent months, a number of mutations in the spike protein have been exemplified by viruses that have grown in alternative hosts such as mink and transmitted back to humans or in immunocompromised chronically infected individuals (Kemp et al., 2020; Oude Munnink et al., 2021; Hayashi et al., 2020). While most of these mutations currently show little evidence of a selective advantage in humans, variants have been identified with multiple mutations in spike, which appear to have distinct selective advantages and have rapidly expanded in prevalence, notably that first identified in Kent in the UK (lineage B.1.1.7) and unrelated variants detected in South Africa (501Y.V2 also known as B.1.351) and Manaus in Brazil (P.1). All of these contain mutations in the ACE2 receptor binding footprint of the receptor binding domain (RBD), one in B.1.1.7, three in 501Y.V2, and three in P.1, with the N501Y mutation being common to all.


"N501Y" refers to the 501st amino acid residue in the spike protein. The "N" refers to the asparagine that was in that position in the original virus first sequenced in Wuhan patients which has been replaced by a tyrosine ("Y" in the mutant "B.1" series. I have read elsewhere that it has been recently discovered that this mutant is slightly more lethal than the original, and also that it is more infectious.

The tests described herein are in vitro, sometimes called, someone niavely as being "test tube." There is very little evidence that this variant has reduced the protective effects of the existent vaccines by a large amount, and the vaccines are still helping us in a very big way.

Still, the need to not panic does not preclude an understanding, as mentioned in the introductory text, that this virus can, and does mutate, and given the situation. Therefore it is a good idea to hold on to supplies you may have, such as masks and sanitizers.



Some pictures from the text:



In the caption, "RBD" refers to the "receptor binding domain," the part of the spike protein that attaches to the ACE2 protein on the surface of cells.

The caption:

Figure 1The B.1.1.7 variant spike protein and effect on ACE binding of the N501Y mutation

(A) The SARS-CoV-2 spike trimer is depicted as a gray surface with mutations highlighted in yellow-green or with symbols. The RBD N501Y and the NTD 144 and 69–70 deletions are highlighted with green stars and red triangles, respectively. On the right, a protomer is highlighted as a colored ribbon within the transparent gray spike surface, illustrating its topology and marking key domains.

(B) The RBD “torso” analogy. The RBD is represented as a gray surface with the ACE2 receptor binding site in dark green. Binding sites for the panel of antibodies (Dejnirattisai et al., 2021) on which this study draws are represented by spheres. The spheres represent the point at which placing spherical antibodies would optimally predict the BLI competition data and are colored according to their neutralization, from red (potent) to blue (non-neutralizing). The position of the B.1.1.7 N501Y mutation in the RBD is highlighted in light green toward the right shoulder.

(C) Proximity of ACE2 to N501Y. The RBD is depicted as in (B) with ACE2 bound (in yellow cartoon format) with glycosylation drawn as sticks.

(D) Left panel: interactions of N501 of WT RBD with residues Y41 and K353. The structure shown is the complex of N501 RBD with ACE2 determined by X-ray crystallography (PDB ID 6M0J, Lan et al., 2020). When the 501 is mutated to a tyrosine with the conformation seen in the N501Y RBD-269 Fab complex (right panel), Y501 makes T-shaped ring stacking interactions with Y41 and more hydrophobic contacts with K353 of ACE2 (note there are minor clashes of the side chain of Y501 to the end of the K353 side chain, which has ample room to adjust to optimize interactions).

(E) BLI plots for WT (left) and N501Y (right) RBDs binding to ACE2. A titration series is shown for each (see STAR Methods). Note the much slower off rate for the mutant.


Some text:

Characterizing the N501Y mutation in the RBD

The RBD may be likened to a classic human torso; in this analogy, the shoulders and neck are involved in interactions with the ACE2 receptor (Figures 1B and 1C) (Dejnirattisai et al., 2021). In this context, residue 501 lies within the footprint of the receptor on the right shoulder and is involved in hydrophobic interactions, especially with the side chains of residues Y41 and K353 of ACE2 with the 501 mutation from N to Y offering the opportunity for enhanced interactions (Figures 1C and 1D).
Effect on ACE2 affinity

It has been reported that mutations at 501 can increase affinity for ACE2 (Starr et al., 2020; Gu et al., 2020), although these data are not for the mutation to Y. In contrast, Zahradník et al., 2021 report direct selection of N501Y when evolving the RBD to enhance affinity. We therefore investigated the effect of this mutation on ACE2 binding by RBD using biolayer interferometry (BLI) (Figure 1E). The results indicate a marked (7-fold) increase in binding affinity due to a slower off rate: WT RBD(501N)-ACE2: KD 75.1 nM (Kon 3.88E4 /Ms, Koff 2.92E-3 /s), RBD(501Y)-ACE2: KD 10.7 nM (Kon 6.38E4 /Ms, Koff 6.85E-4/s). This is in-line with enhanced interactions of the tyrosine side chain with the side chains of residues Y41 and K353 of ACE2 (Figure 1D). In the context of a multivalent interaction at the cell surface, this effect would be amplified. This alone might account for the selection of the N501Y mutation and an increase in transmission.


The authors utilized a set of 377 antibodies isolated from patients either who had been infected in the first wave. 80 of these have been fully mapped to elucidate the binding sites of the antibodies. In many cases, they found reduced binding.

However, as noted in the first excerpt from the last part of the paper's main text, the reduced binding does not preclude vaccine protection. Notably, the infection can be managed by T-cells as opposed to B-cell antibodies.

The full paper is available for reading for free. It may take some sophistication to understand all that is being said in there, but I think it readable and it's worth mucking around in it. If there are any questions that I may be able to answer, let me know and I'll do my best.

For now, we seem safe, if we've been vaccinated. If we're dumb assed anti-vax Republicans, the Darwin award awaits; this strain is definitely more lethal, although still susceptible to being managed by the vaccines.

Still the situation in India, affording many opportunities to generate new strains suggests that new vaccines may be required at some point. Some that have modified to reflect the new strains have already been prepared and are being tested in patients. We have considerable infrastructure for the manufacture of these, and considerable knowledge capital as well, so we're in relatively good shape. It is important that we do our best to provide other nations with access to these vaccines, since all of humanity shares this risk.

Be safe. Be well.

I learned a new German word today that's relatively new even to Germans, "Dunkelflaute"

I learned it here: Variability in Deeply Decarbonized Electricity Systems (John Bistline, Environmental Science & Technology 2021 55 (9), 5629-5635)

The context:

These resources exhibit variability across different time scales, including subhourly resource fluctuations, larger ramps across multiple hours, sustained periods of high or low output for multiple days (the German term dunkelflaute or “dark doldrums” refers to extended periods with limited sunshine or wind), seasonal effects, and even variability across years and decades (e.g., interannual variation in hydro and wind resources).


While my German is very, very, very, very rusty - it's been years since I did anything significant with that language - I have a feeling that Dunkelflaute worries some people, pisses others off:

Das heißt: In vier Jahren werden nur noch rund 67.000 Megawatt gesicherte Kapazität zur Verfügung stehen, obwohl Deutschland in Spitzenzeiten 81.000 Megawatt verbraucht. Kommt es zu einer „kalten Dunkelflaute“ ohne nennenswerten Wind- und Solarstrom, wäre die deutsche Stromversorgung in diesen Stunden, Tagen oder Wochen auf ausländische Lieferungen zwingend angewiesen.

Die Zeiten, in denen solche Knappheiten am Markt neue Investitionsanreize auslösten, sind vorbei. „Stattdessen sind wir schon heute auf eine Reihe von Reparaturmaßnahmen angewiesen: Netzreserve, Kapazitätsreserve oder netztechnische Betriebsmittel kaschieren mehr schlecht als recht die Defizite der deutschen Energiepolitik und Marktkonditionen“, schimpft Kapferer: „Auf Dauer wird das nicht funktionieren.“


In der „kalten Dunkelflaute“ rächt sich die Energiewende

With my bad German, I translate this as: The Energy Transition Is Taking Revenge in Cold, Dark, Doldrums.

I could be wrong though, maybe it doesn't translate that way. Maybe it translates as "Don't worry; be happy."

Here's another reference to Dunkelflaute, in English from another journal, Mesoscale modeling of a “Dunkelflaute” event (Basu et al., Wind Energy, Volume24, Issue1 January 2021 Pages 5-23)

An excerpt from this open source journal:

Unlike fossil fuel‐based energy sources, some of the renewable energy sources (especially, wind and solar) strongly rely on meteorological conditions. As such sources of energy play a larger role in electricity networks, this presents an increasing challenge in terms of balancing supply and demand. Therefore, it is important to increase our understanding and forecasting capability of certain weather phenomena which can result in adverse renewable energy production from a system operator perspective. Such advanced knowledge and tools will further support the continuing growth of renewables in the foreseeable future.

In this paper, we focus on one such weather phenomenon called “Dunkelflaute” as it is rapidly becoming a major concern for the renewable energy community.6 The word Dunkelflaute was coined by combining two German words “Dunkelheit” (darkness) and “Windflaute” (little wind) to describe heavy overcast skies and weak wind conditions. These meteorological events can last from a few hours to a few consecutive days. It is needless to say that under the influence of such a meteorological condition, little or no wind and solar energy can be produced.

On the 30th April 2018, an unexpected Dunkelflaute event occurred over the southern part of the North Sea and caused a large imbalance in renewable power generation and overall consumption. Given the acuteness of the situation, TenneT—the main transmission system operator for Germany and the Netherlands—had to issue an emergency alert in the Netherlands.7, 8 The crisis could not be avoided by simple load management or by making use of reserve power; instead, a substantial amount of electricity had to be imported from neighboring countries at high market price.

This Dunkelflaute event was not an isolated episode. As a matter of fact, over the past few years, several Dunkelflaute events occurred in Belgium,9-12 Germany,6, 13-15 and other neighboring countries. Some of them caused significant impacts on the power grids and electricity markets. There is no reason to believe that the occurrences of Dunkelflaute will subside in the future. Instead, with the ever increasing penetration of renewables in the power grid, the (negative) impacts of Dunkelflaute events will likely become more and more detrimental.
.

Germany by the way, is famous for phasing out nuclear energy, which will be complete by the end of next year. They have announced the intention to phase out coal "by 2038." At the current rate, of 2.4 ppm per year of carbon dioxide accumulations , as determined from the weekly Mauna Loa CO2 data from last week using a 12 month running average of weekly data, "by 2038," the carbon dioxide concentrations on this planet will be 444 ppm, up from 420.01 ppm recorded in the week beginning April 25, 2021.

In 2011, when the Energiewende plan was first published, including a nuclear phase out, the rate of increase in the dangerous fossil fuel waste carbon dioxide in the planetary atmosphere, again as a 12 month running average of weekly data, was 2.03 ppm/year, as recorded on May 8, 2011.

(The figures rely on the average difference between the weekly reading and the reading of the same week 10 years earlier.)

In the year 2000, for the week beginning May 7, 2000, the figure was 1.50 ppm/year. The concentration of the dangerous fossil fuel waste carbon dioxide in the planetary atmosphere as measured at Mauna Loa for the week beginning May 7, 2000 was 371.70 ppm.

Don't worry, be happy.

Air pollution from coal kills people by the way. Air pollution deaths worldwide easily outstrip, on a daily basis, Covid-19 deaths.

So called "nuclear waste," hasn't killed anybody in recent times, but lots of people pull their hair out claiming it could, some day, somewhere. In modern times could is a much scarier word than is, as in "nuclear waste could kill someone someday" as opposed to "coal air pollution is killing people every day.

Am I crazy for thinking Germany, once the country of Planck, Sommerfeld, Hilbert, Born, Heisenberg and others of similar powers, has things ass backwards?

I guess I am.

Dunkelflaute. Dark doldrums.

For a last comment, I'll excerpt a few remarks from another paper using the word "Dunkelflaute" from the Oxford Institute for Energy Studies, leaving aside what should be, but perhaps isn't, obvious, that no country that burns dangerous natural gas is "decarbonized."

The role of natural gas, renewables and energy efficiency in decarbonisation in Germany: The need to complement renewables by decarbonized gas to meet the Paris target

Focusing only on renewables in power and not addressing thermal power will not automatically lead to reaching the decarbonisation target and will jeopardise reliability of supply for Germany and its neighbours. In the end, the resulting upcoming shortfall of dispatchable power may even throw into question the nuclear phaseout as fixed by law. With the closing of dispatchable capacity (nuclear – by law, conventional – due to market drivers) Germany will face an increasing gap between available dispatchable power and peak load, according to the NEP 2030. This gap cannot be filled with whatever extra capacity there is in wind and PV. Turning to neighbours for reliable power is not an option, as these countries are facing similar problems, as well as other country-specific problems.


The reason that so called "renewable energy," was phased out in the 19th and early 20th century was that most people, even more so than today, lived short, miserable lives of dire poverty.

Even today, poverty is best defined by a lack of access to energy.

It is possible to provide reliable and clean and safe energy for those who have it as well as those who still lack it except for scraps of "renewable biomass." This is only true, however, if we stop lying to ourselves. Our water is already dependent on the weather, and is in fact, severely threatened by climate change. Is it really a good idea to make the electricity for the computers we run to say how great so called "renewable energy" is dependent on the weather as well? The electricity to run oxygen generators? Surgical lamps? Our much loved television sets? Refrigerators? Freezers.

Dunkelflaute.

The wikipedia entry for the word:

Dunkelflaute is a term used in the energy sector for a period of time in which little to no energy can be generated with the use of wind and solar power. The term is German in origin and a blend word of the german ‘Dunkelheit’ (darkness) and ‘Flaute’ (little wind). The periods called Dunkelflaute are a big issue in energy infrastructure in which a significant amount of electricity is generated by wind and solar power. To ensure power during such periods alternative energy sources must be present in a sufficient capacity. When that happens countries use either fossil fuels (e.g. oil, methane gas, coal) or hydroelectricity, nuclear power and, less often, energy storage to prevent a power outage.[1][2][3][4][5]

The first use of the term in an academic paper is in 2014.[6]


Dunkelflaute, some ideology is Dunkelflaute.

I just have one thing to say in a time of rising crisis.

I am extremely grateful the Joe Biden is at the helm.

The myriad ways sewage surveillance is helping fight COVID around the world

This is a news item from Nature, which I hope is open sourced:

The myriad ways sewage surveillance is helping fight COVID around the world

Wastewater tracking was used before the pandemic to monitor for polio and illicit drug use, but interest in the field and its applications has now ballooned.


One of my earliest memories as a child was being amazed by toilet bowls, not only how they worked without requiring electricity (that I could see) but also where the "stuff" went.

It appears that fascination never really went away; I find myself thinking about this sewage all the time, not only in the very practical (and sometimes expensive) issue of maintaining my home septic system, but also in connection with broad environmental issues, and equally important, human development goals; about two billion human beings on this planet lack access to improved sanitation, something I find unacceptable in the extreme. Understanding sewage - in many ways one of the worst waste problems in the world - only dangerous fossil fuel waste and biomass combustion waste is responsible for more unnecessary deaths - is extremely important to address the rising fresh water crisis, the collapse of ecosystems in the oceans, and, more subtly, addressing an issue that is going to hit future generations very, very, very hard as a result of our inattention, phosphorous flows.

The extremely advanced development of what has become late in life, my absolute favorite analytical chemistry technique, mass spectrometry, has allowed us to understand things about sewage we never could access previously, in particular the environmental fate of many different kinds of products, not only "personal care products" like soap and cosmetics and pharmaceutical metabolites and unmetabolized excreted pharmaceuticals, collectively abbreviated "PPCP" in the literature, but also the fate of things like paints, flame retardants, fire fighting foams, fabric protection agents...the list goes on and on.

And now the study of sewage is providing insight, using qPCR, the spread of Covid.

Some excerpts from the news item cited at the outset of this brief post:

From the subarctic community of Yellowknife, Canada, to the subtropical city of Brisbane, Australia, scientists in more than 50 nations are now monitoring the spread of SARS-CoV-2 in sewage. The number of sewage-surveillance programmes tracking COVID-19 has exploded during the past year from a dozen or so research projects to more than 200, following the discovery that whole virus particles and viral fragments are shed in faeces.

The information garnered is helping scientists to track down cases, predict surges, identify where to target testing, and estimate overall numbers of infected people in cities or regions. Although sewage surveillance has been used for several decades to identify polio outbreaks and target immunization programmes, and, more recently, to detect illicit drug use, the pandemic has brought new focus and investment in it as a means of tracking public health.

“There was always an interest in wastewater epidemiology, but now it’s taken flight,” says Ana Maria de Roda Husman, an infectious-diseases researcher at the Netherlands National Institute for Public Health and the Environment in Bilthoven.

Since early 2020, SARS-CoV-2 sewage projects have taken off around the world as wastewater experts pivoted to concentrate on the crisis. But the scale and focus of surveillance programmes varies, depending on how severely countries or communities have been hit by the pandemic.

The number of ways sewage surveillance is being used is dizzying. In the United Arab Emirates, researchers have been testing sewage from commercial aircraft to see whether incoming flights were carrying infected passengers1. Scientists in Hong Kong are monitoring sewage in apartment buildings to find undetected infections, and, in Yellowknife, health officials are testing wastewater to discover which viral variants have made it to their city, just 400 kilometres from the Arctic Circle.

Early-warning system
One common application of such surveillance programmes is as an early-warning system. People who are infected start shedding virus fragments a few days before they show symptoms, and de Roda Husman uses this to predict hospitalization numbers a few days ahead of time.

Other groups are using wastewater to find and suppress outbreaks on a much smaller scale...

...Challenges for developing countries

However, more than 70% of sewage-surveillance programmes are in high-income countries2, which have poured resources into wastewater epidemiology. Many researchers in the developing world are struggling.

“Testing in India is incredibly challenging as sewage systems are fragmented,” says Sudipti Arora, an environmental scientist at the Dr. B. Lal Institute of Biotechnology in Jaipur, India. Only about one-third of all towns have sewer networks, she says. “Consequently, slums and rural areas remain largely untested...”

...Many scientists working in the field say that a rare positive outcome of the pandemic might be that it will normalize the use of wastewater to monitor public health — whether for future pandemics or to track other health indicators, such as hormones that indicate stress or levels of caffeine consumption.

“Wastewater epidemiology was under the radar,” says Karthikeyan. “Now, it’s come to the forefront.”
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