This Week in Sustainability Podcast

20 Fight Sulfites

In which Felicia explains the many sources, the chemistry, and the toxicity of sulfites and sulfates. Sulfites are widespread in food, both processed and natural. They have been strongly linked to inflammatory bowel diseases by gut bacteria that use sulfate as an energy source. Sulfates are found in many personal care and household cleaning products. Felicia offers many suggestions on how to avoid sulfites and sulfates. It’s good for you and for the environment.

Sources

1. Deng, K., Wang, L., Nguyen, S. M., Shrubsole, M. J., Cai, Q., Lipworth, L., Gupta, D. K., Zheng, W., Shu, X.-O., and Yu, D. (2025) A dietary pattern promoting gut sulfur metabolism is associated with increased mortality and altered circulating metabolites in low-income American adults, eBioMedicine 115.10.1016/j.ebiom.2025.105690: 10.1016/j.ebiom.2025.105690
2. Dordevic, D., Capikova, J., Dordevic, S., Tremlová, B., Gajdács, M., and Kushkevych, I. (2023) Sulfur content in foods and beverages and its role in human and animal metabolism: A scoping review of recent studies, Heliyon9.10.1016/j.heliyon.2023.e15452: 10.1016/j.heliyon.2023.e15452
3. Owczarek, D., Rodacki, T., Domagała-Rodacka, R., Cibor, D., and Mach, T. (2016) Diet and nutritional factors in inflammatory bowel diseases, World Journal of Gastroenterology 22, 895-905.10.3748/wjg.v22.i3.895: 10.3748/wjg.v22.i3.895
4. Pfau, A., López-Cayuqueo, K. I., Scherer, N., Wuttke, M., Wernstedt, A., González Fassrainer, D., Smith, D. E. C., van de Kamp, J. M., Ziegeler, K., Eckardt, K.-U., Luft, F. C., Aronson, P. S., Köttgen, A., Jentsch, T. J., and Knauf, F. (2023) SLC26A1 is a major determinant of sulfate homeostasis in humans, The Journal of Clinical Investigation 133.10.1172/JCI161849: 10.1172/JCI161849

19 Ain’t No Paint Like Linseed

In which Felicia interviews Michiel Brouns of Brouns & Co., who got his start in restoring historical buildings. We talk all about the sustainability of all-natural boiled linseed oil paint: how it polymerizes, that it is derived from flax seeds, and how it is biodegradable in the environment, so it makes no toxic microplastics. The paint requires nothing to dilute it, no solvents, so it contains only trace natural volatile organic compounds (VOCs). The pigments are non-toxic minerals, oxides like iron and zinc. Even though the cost is higher per can of paint, you apply it in very thin coats and it soaks into the wood, protecting it for the long term, without trapping moisture that causes wood to rot when painted with modern synthetic polymer paint. Linseed paint has protected buildings for thousands of years, so it is really quite inexpensive in the long run. Host–Felicia Etzkorn, Professor Emerita of Chemistry at Virginia Tech, with music by Wendy Godley of The Kind.

References:

Linseed Paint &Oil – A Practical Guide to the Traditional Production and Application by Michiel Brouns, The Crowood Press © Michiel Brouns 2023

Brouns & Co. linseed oil paint, putty, etc: https://linseedpaint.com/

Le Tonkinois linseed oil marine varnish: https://www.le-tonkinois.com/home-en.html

18 Toothy Truth

In which Felicia explains the sustainability of some toothpaste ingredients. This is a partial list of ingredients, based mainly on two tubes of toothpaste in her bathroom, Sensodyne Pronamel Multi-Action and Burt's Bees Complete Multi-Care. The ingredients are classified by the function they serve in toothpaste: 1) active ingredients, 2) sticky stuff, 3) surfactants (detergents), 4) sweeteners, 5) whiteners, 6) minerals, and 7) flavors.

Sources include:

Wikipedia

PubChem

Sampaio, F.C.; Oliveira, A.F.B.d.; Fernandes, N.L.S.; Gentile, A.C.C.; Marinho, G.B.; B.necker, M.J.S.; Paschoal, M.A.B.; D’Alpino, P.H.P.; Vilhena, F.V. Silicon-, Silica-, and Silicate-Toothpastes for Remineralization and Repair of Teeth: A Scoping Review. Oral 2024, 4, 467–486. https://doi.org/10.3390/oral4040038 

Kim, D., Seok, J.K., Kim, M. et al. Safety assessment of cocamidopropyl betaine, a cosmetic ingredient. Toxicol Res. 40, 361–375 (2024). https://doi.org/10.1007/s43188-024-00243-2

Rayssa Ferreira Zanatta, Daniele Mara da Silva Ávila, Karen Mayumi Miyamoto, Carlos Rocha Gomes Torres, Alessandra Bühler Borges; Influence of Surfactants and Fluoride against Enamel Erosion. Caries Res 11 January 2019; 53 (1): 1–9. https://doi.org/10.1159/000488207

Lai, C.; Nguyen, A.; Ye, L.; Hao, J.; Koo, H.; Mante, F.; Ozer, F. Antibacterial and Physical Properties of PVM/MA Copolymer- Incorporated Polymethyl Methacrylate as a Novel Antimicrobial Acrylic Resin Material. Molecules 2022, 27, 8848. https://doi.org/10.3390/molecules27248848 

Söderling, E., Pienihäkkinen, K. Specific effects of xylitol chewing gum on mutans streptococci levels, plaque accumulation and caries occurrence: a systematic review.BMC Oral Health 25, 1275 (2025). https://doi.org/10.1186/s12903-025-06602-1 

Boerner, L.K. What is dental enamel, and how does it protect your teeth? Chem Eng News Oct 19, 2020

17: Remodeling Materials

In which Felicia describes the materials choices for her kitchen remodel, and her guest, Helene Renard, Professor of Interior Design in the School of Architecture + Design at Virginia Tech, describes the “Healthier Materials and Sustainable Building” course she took with the Healthy Materials Lab at the Parsons School of Design. Host–Felicia Etzkorn of Virginia Tech, with music by Wendy Godley of The Kind.

Green Kitchen Remodel: https://mcdn.podbean.com/mf/web/e8tg8v/Green_Kitchen_Lecture_2015am1wy.pdf

Course: https://healthymaterialslab.org/learning-hub/e-learning-online-certificate-program

Healthy Materials Lab: https://healthymaterialslab.org/about/team

https://healthymaterialslab.org/

 

16: PFAS Sass

In which we discuss per- and poly-fluoroalkylsubstances (PFAS) with Carol Kwiatkowski of the Green Science Policy Institute (https://greensciencepolicy.org), their properties, function, consumer products, toxicity, persistence, chemical analysis, and regulation both in the US and EU. Some companies, like Keen, are eliminating PFAS from their products. We then discuss a few green substitutes, including Solberg Co.'s firefighting foam, a fatty acid coated cellulose, and iron skillets. Host–Felicia Etzkorn of Virginia Tech, co-host–Jamie Ferguson of Emory & Henry College, with music by Wendy Godley of The Kind.

PFAS review: Kwiatkowski, C. F.; Andrews, D. Q.; Birnbaum, L. S.; Bruton, T. A.; DeWitt, J. C.; Knappe, D. R. U.; Maffini, M. V.; Miller, M. F.; Pelch, K. E.; Reade, A.; Soehl, A.; Trier, X.; Venier, M.; Wagner, C. C.; Wang, Z.; Blum, A., Scientific Basis for Managing PFAS as a Chemical Class. Env Sci & Tech Letters 2020, 7 (8), 532-543.

https://pubs.acs.org/doi/10.1021/acs.estlett.0c00255

EPA Reassessment: https://cen.acs.org/environment/persistent-pollutants/US-EPA-deems-two-GenX-PFAS-chemicals-more-toxic-than-PFOA/99/web/2021/10?utm_source=Newsletter&utm_medium=Newsletter&utm_campaign=CEN

Alternatives: https://pfascentral.org/pfas-free-products/

Keen PFAS-free: https://www.keenfootwear.com/conservation/blog-article-20390.html

Solberg Co firefighting foam: https://www.perimeter-solutions.com/class-a-b-foam/

PFAS in cosmetics: https://pubs.acs.org/doi/10.1021/acs.estlett.1c00240

PFAS in fracking: https://www.nytimes.com/2021/07/12/climate/epa-pfas-fracking-forever-chemicals.html

Dark Waters, Movie about PFAS in WV with Mark Ruffalo: https://www.yidio.com/movie/dark-waters/210401

Binding of PFOA to human serum albumin: Maso, L. et. al., Unveiling the binding mode of perfluorooctanoic acid to human serum albumin. Protein Sci 2021, 30 (4), 830-841.https://onlinelibrary.wiley.com/doi/10.1002/pro.4036

Breaking down PFAS: Lockwood, D., Photocatalyst shreds drinking water contaminant PFOA. Chem & Eng News 2018, 96 (36). https://cen.acs.org/environment/persistent-pollutants/Photocatalyst-shreds-drinking-water-contaminant/96/i36

Vermont regulations passed: https://thehill.com/changing-america/well-being/longevity/554680-vermont-governor-signs-first-in-nation-restrictions-on

15: News Roundup: Blues, Catalytic Converters, and Fracking

In which we discuss the recent development of a series of new blue pigments, the theft of catalytic converters for the rhodium, and the health effects of fracking chemicals. Hosted by Felicia Etzkorn of Virginia Tech, co-host Jamie Ferguson of Emory & Henry College, and music by Wendy Godley of The Kind.

Blue pigments: https://chemistry.oregonstate.edu/content/story-yinmn-blue

Catalytic converter theft: https://www.npr.org/templates/story/story.php?storyId=129047092

https://www.washingtonpost.com/world/africa/catalytic-converter-theft-south-africa-rhodium/2021/03/03/dc288192-777d-11eb-9489-8f7dacd51e75_story.html

Fracking chemicals: https://www.ehn.org/fractured-series-on-fracking-pollution-2650624600/fractured-fracking

 

14: Chemical Alt-Rock

In which we discuss the opportunities for substituting safer chemical alternatives for consumer products in current use with our guest, Joel Tickner of the University of Massachusetts, Lowell. We don’t need to wait for green chemistry to come up with great alternatives, many have already been designed. We need to collaborate with businesses to turn towards better alternatives, rather than imposing regulations away from the bad stuff, risking drop-in substitutions that are just as bad. Host–Felicia Etzkorn of Virginia Tech, co-host–Jamie Ferguson of Emory & Henry College, with music by Wendy Godley of The Kind.

Resources

1. Joel A. Tickner, Rachel V. Simon, Molly Jacobs, Lindsey D. Pollard & Saskia K. van Bergen (2021) The nexus between alternatives assessment and green chemistry: supporting the development and adoption of safer chemicals, Green Chemistry Letters and Reviews, 14:1, 21-42, DOI: 10.1080/17518253.2020.1856427
    https://www.tandfonline.com/doi/full/10.1080/17518253.2020.1856427
2. Tickner J, Jacobs MM, Mack NB (2019) Alternatives assessment and informed substitution: A global landscape assessment of drivers, methods, policies and needs. Sustainable Chemistry and Pharmacy 13:100161. https://www.sciencedirect.com/science/article/pii/S235255411930052X
3. O'Brien M. 2000. Making Better Environmental Decisions: An Alternative to Risk Assessment, MIT Press Cambridge, MA. https://mitpress.mit.edu/books/making-better-environmental-decisions

13: Next Seven Generations

In which we discuss sustainable, plant-based cleaning products, oxygen-bleached paper products, recyclable and recycled packaging, transparent labeling, and consumer education with Martin Wolf, Director of Sustainability & Authenticity at Seventh Generation. Host–Felicia Etzkorn of Virginia Tech, co-host–Jamie Ferguson of Emory & Henry College, with music by Wendy Godley of The Kind.

Great resource for sustainability and environmental justice issues:

https://www.seventhgeneration.com/home

12: With the Weight of Lead

In which we discuss the uses of lead in gasoline (and the temporally and geographically associated violence), avgas, pipes, and car paint primer, and the greener replacements for these products—ethanol as replacement for tetraethyl lead as an anti-knock additive in gasoline, potential plastic replacements for lead pipes, and yttrium as a replacement for lead car primer.Host–Felicia Etzkorn of Virginia Tech, co-host–Jamie Ferguson of Emory & Henry College, with music by Wendy Godley of The Kind.

Abelsohn AR, Sanborn M (2010) Lead and Children, Canadian Family Physician 56:531. https://www.cfp.ca/content/56/6/531

EPA Final Revisions to the Lead and Copper Rule: https://www.epa.gov/ground-water-and-drinking-water/final-revisions-lead-and-copper-rule

Angus Chen, Zapping Lead Pipes with Electricity Could Make Them Safer for Drinking Water, Scientific American, April 4, 2019.

PPG Industries, Yttrium as a Lead Substitute in Cationic Electrodeposition Coatings, EPA  Green Chemistry Challenge Award 2001. https://www.epa.gov/greenchemistry/presidential-green-chemistry-challenge-2001-designing-greener-chemicals-award

Grateful Dead, New Speedway Boogie excerpt, from What a Long Strange Trip It’s Been, 1977.

11 Farming is Elemental

In which we interview Anthony Flaccavento, organic farmer, author, activist, and local politician, about his sustainable practices to incorporate carbon, nitrogen, and other essential elements back into the depleted soil of his former tobacco farm in southwest Virginia. No-till agriculture not only sequesters carbon and nitrogen in the soil, it balances soil water content in both drought and flood times. Host–Felicia Etzkorn of Virginia Tech, co-host–Jamie Ferguson of Emory & Henry College, with music by Wendy Godley of The Kind.

Resources

Anthony Flaccavento Building a Healthy Economy from the Bottom Up: Harnessing Real World Experience for Transformative Change (University Press of Kentucky, 2016) https://www.kentuckypress.com/9780813167596/building-a-healthy-economy-from-the-bottom-up/

SCALE — Sequestering Carbon, Accelerating Local Economies https://www.anthonyflaccavento.com/scale-inc

Savory Institute https://savory.global

National Ecological Observatory Network https://www.neonscience.org

How to Bury Carbon? Let Plants Do the Dirty Work in Nautilus

http://cshl.nautil.us/article/657/how-to-bury-carbon-let-plants-do-the-dirty-work?mc_cid=5c3e66ab03&mc_eid=71fa1ec799

Crop innovations can protect yields and improve food quality in a changing climate

https://cen.acs.org/food/agriculture/Protecting-harvest/98/i6

Climate Change Take 5 with Tony (S.2, Ep. 4)

https://www.bottomupeconomy.org/climate-change-sustainable-farming/

Sustainable farming and social justice:

Chris Newman of Sylvanaqua https://www.sylvanaqua.com

Nina Ichikawa of the Berkeley Food Institute https://food.berkeley.edu

Joel Salatin’s Unsustainable Myth: His go-it-alone message made him a star of the food movement. Then a young Black farmer dug into what he was really saying. https://www.motherjones.com/food/2020/11/joel-salatin-chris-newman-farming-rotational-grazing-agriculture/