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Lab Safety

Reactions: Trust in science, lab accidents, climate change, and Carolyn Bertozzi

April 28, 2024 | A version of this story appeared in Volume 102, Issue 13

 

Letters to the editor

Trusting science

Re Judith Giordan’s remarks on trusting science in C&EN’s April 1, 2024, issue (page 33):

A lot of trust derives from communicating in a manner that renders the subject understandable in the context of the reader’s or listener’s life experiences.

Example: 30 years ago, Richard Holsworth and I tackled the concept of what “random” actually looks like in the real world by running dozens of mixing tests using bags of mixed-color jelly beans and photographing and analyzing the results of repeat shaking experiments. We repeated the experiments with costume jewelry beads and random-number tables.

Our goal was to understand why individual pigment particles seemed to clump together in dried paint films rather than existing as singlets, which was theoretically preferred for maximum optical efficiency, despite a century of effort in our industry to improve dispersion. The prevailing belief at the time was that it was due to inadequate colloidal stability of the pigment dispersion in the wet state.

Instead, we found that all random systems naturally cluster, the size and frequency being related to the concentration of the dispersed phase in the continuous phase; it had nothing to do with the colloidal stability of the dispersed phase. Thus, achieving single-particle distributions of pigments in dried paint films would require some nonrandom intervention (such as encapsulation with another material).

Colloidally unstable systems readily formed spherical agglomerates in the liquid state, thereby minimizing surface area for that system. Clustered (stable) systems formed aggregates of extended size and irregular shape, which regularly exhibited percolation behavior (spanning the dimensions of the film) above a certain minimum concentration, typically on the order of around 20%.

When presenting this to a national meeting of our professional organization, we received comments from nonscientists that it was the best talk they’d ever heard. When presenting this to a Gordon Research Conference, that audience spent over an hour watching a video that Richard created showing the live formation of clustering during the drying process, again with no evidence of instability such as coagulation.

In both cases, the comments cited the translation of the concept into the context of common observation in routine living. In short, they trusted the results presented because they made sense in their context.

Lou Floyd
Independence, Ohio

 

Lab accidents

I just had to comment on the two pieces from Newscripts in the April 1 issue of C&EN (page 40). In the first piece, the revelation by Jessica Pomerantz reminded me of an experience I had in 1977 in a senior-level physical chemistry class at Iowa State University. It involved a Lewis acid-base reaction of boron trifluoride and trimethylamine in a rather complex glass network that included a liquid-nitrogen cold trap because the reaction was so exothermic. The instructions for valve settings and operation were quite specific and stated that if they were not followed explicitly, the apparatus could explode. I arranged all valves meticulously, or so I thought, and then opened the valve on the BF3cylinder, which was connected to the glassware inlet by a rubber hose. Unfortunately, the one valve I forgot to open was the inlet valve to the apparatus. Within seconds, the hose popped off, and I had a fuming ball of BF3within 1 ft (0.3 m) or so of my face. I had the presence of mind to shut off the cylinder valve, and then I watched as the fuming cloud, which stayed intact, floated to the ceiling and rolled all the way to the other corner and escaped through a roof vent. It reminded me of the movie The Blob, except this blob rolled along the ceiling and not the floor. My classmates and the teaching assistant were so absorbed in their own work that they did not observe the blob. Nobody at Iowa State ever learned of my slight mistake. I successfully completed the experiment on the second attempt.

This brings me to the second Newscripts article. During my many years in industry and to this day, I have written numerous articles for various technical trade magazines, including Chemical Engineering, Power Engineering, and others. I am now a self-employed technical writer and consultant. From the experience above and several others during my career (such as tripping and falling into several inches of yucky flue gas desulfurization sludge), I can decidedly appreciate the title of the second piece, “And This Is Why We’re Journalists Now.”

Brad Buecker
Lawrence, Kansas

After reading your March 28 tales of broken glassware, I was reminded of my own contribution to the field. As a first-year chemistry student and also indoor track team member, I missed one lab for an away meet and arranged for a solo makeup in another lab section. So as they were getting their chalk talk in the front of the lab, I was at the back setting up my stuff. I’d gotten a considerable amount of glassware, nested beakers, etc. and put it all on a towel to avoid making noises that would disturb the teaching assistant’s talk up front. That failed spectacularly when I spilled something and grabbed the towel for damage control, launching my entire pile of glassware onto the floor and obliterating considerably more than my semester breakage allowance in one fell swoop.

The postscript is that running my own company in the decades since my little disaster, I’ve been able to comfort numerous employees who broke a piece or two of glassware, simply by recounting my own tale. Not one ever came close to my single-shot wreckage, and my story always helped put them at ease.

Robert O. Harrison
South Portland, Maine

Your article regarding broken glassware reminded me of an experience from years ago:

In the early 1970s I was a teaching assistant in an organic chemistry lab in Purdue University’s Chemistry Department. Each student was issued a ground glassware kit with which to perform that semester’s experiments. At the end of the semester, the TA reviewed each kit with the student to identify parts that needed to be replaced at the student’s expense. With one student I rotated a 100 mL round-bottom flask and discovered a dime-size hole near the flask bottom. I pointed to the flask and looked at the student expectantly. He immediately deadpanned, “Powerful leaving group!” (They had just been studying SN1 and SN2 reactions in professor Joseph Wolinsky’s lecture class.) To this day I appreciate the cleverness of his response, but he still had to buy a new flask.

This event stuck in my mind these 50-plus years, and I still remember his name (Ed Orme) and how he looked. I don’t know what he became, but he might have made it as a stand-up comic.

Joseph T. Valko
Pittsburgh

 

Mitigating climate change

William A. Levinson states that direct air capture (DAC) of carbon dioxide is “likely to be a waste of money” (C&EN, Feb. 19, 2024, page 5). He recommends planting trees for a more economical approach to carbon capture.

Let’s calculate how much carbon a trillion trees would capture: at maturity (about 40 years for some trees), 0.022 metric tons (t) per tree × 1 trillion = 22 billion t of the gas, or 22 Gt.

In contrast, in 2023, energy-related activities spewed about 37.4 Gt of CO2 into the atmosphere, according to the International Energy Agency. So, unabated, 1,496 Gt would be emitted during the 40-year growth of a trillion trees.

It is estimated that the world has cumulatively emitted 1,500 Gt of CO2 since 1751 or, when including land-use change, nearly 2,600 Gt since 1850. These emissions are now distributed between air and ocean. The goal of net zero (NZ) is for humans to no longer contribute to greenhouse gas (GHG) buildup. But NZ cannot improve our climate once we reach NZ but merely (somewhat) prevent the climate from worsening.

The Kenyan DAC plant described in C&EN takes a nanodrop out of the accumulated GHGs. However, other DAC projects are drawing the gas (e.g., Climeworks’ Orca, which runs on geothermal energy). New, larger, and more efficient DAC plants are coming on line in Texas, Iceland, and elsewhere. If the technology becomes profitable (i.e., low-cost conversion of CO2to valued organics), the number and size of these plants will multiply to a point that they could make a difference.

Unfortunately, a trillion trees and our near-future DAC plants combined still will not remove enough CO2. We need to start drawing the gas out of the ocean (direct ocean capture, or DOC), but these technologies are not ready.

Up to two-thirds of the world’s glaciers are on track to disappear by 2100. Once dry, they will no longer feed the rivers below. Hungry and thirsty millions will migrate en masse.

Consider this turning point: as the glaciers recede, the black earth below will be warmed by the sun, and the soil will emit both CO2 and methane (which has 84 times CO2’s warming effect over 20 years). In the near future, human emissions will be dwarfed by Earth’s contribution.

Humankind is running out of time. We need to plant trees, meet NZ, and rapidly ramp up DAC and DOC ASAP. We must avoid this turning point!

David Allen Marsh
Bonita Springs, Florida

 

Carolyn Bertozzi

My personal accolade for Carolyn Bertozzi (profiled in March 11/18, 2024, page 32) pales with every one she has deservedly received, but I am compelled to air it.

My first encounter with Carolyn was in a review session she held for chemistry 112A, organic chemistry for chem majors (the class held under the College of Chemistry at the University of California, Berkeley, not the Department of Chemistry). Even now, the clarity with which she parsed and explained organic chemistry remains unrivaled in my mind. It wasn’t just that she towered over the very fine teaching assistant teaching my section. She was better than the guy teaching the class, Peter G. Schultz, an absolutely masterful teacher at, then, 33.

I spent the following year doing synthesis under another member of the Mark Bednarski group. I really wish I had interacted more with Carolyn, but I recall having to reassure Carolyn on one occasion that her career would not end in Rutgers University (no slight in that outcome) in one exchange. Her humility was real, despite her awareness of her capabilities, and it’s manifest in every interview and exchange.

There were other gay members of the Bednarski group, and I relished the long days of running flash chromatography columns and talking to my lab mate on every conceivable subject. It was the revelation to the young undergraduate that being in the company of absolutely brilliant people far outweighed the desire to succumb to ancient, persistent cultural biases, and how hollow such notions are.

On a peculiarly odd level, I am grateful that Lewis Hamilton is one of the greatest Formula One drivers of all time and he’s Black and that Carolyn will be enshrined as a towering figure in chemistry for the rest of time and she’s gay—precisely because they both draw attention to the fact that these considerations simply don’t matter. It should be society’s most sacred duty to ensure that people this talented and this driven are given the opportunity to do the amazing things of which they are capable. It is a profound stigma on society that such rights were withheld from giants like Alan Turing.

It was a humbling experience to hear of Carolyn’s Nobel award. I was shocked but not surprised. I only wish I had her as a TA and as a research mentor, but I am grateful for my brief brush with greatness.

Payam Minoofar
San Buenaventura, California

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