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What You’re Reading reviews the most-viewed posts and articles from The Synergist, our two weekly newsletters, and SynergistNOW over the previous month. In March, readers were drawn to stories about a NIOSH research project on 3D printing, the causes of an explosion at a chemical plant that produces ethylene oxide (EtO), the latest revisions to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS), and the challenges of networking in occupational and environmental health and safety.

Most read in Synergist Newswire:

3D Printing: Protecting Workers Turning Plastic Waste into Filament

3D printing, also known as additive manufacturing, is used in workplaces as varied as laboratories, factories, hospitals, schools, and libraries. By melting recycled items like milk jugs and converting them into filament for use in 3D printers, additive manufacturing could help reduce the amount of plastic waste, but little is known about the chemicals released by this process. NIOSH is partnering with external researchers to study emissions from the conversion of high density polyethylene into filament. HDPE is used in food containers, shampoo bottles, and other plastics. Preliminary results suggest that the more the material is recycled, the fewer harmful emissions it releases.

Most read in The Synergist Weekly:

CSB Report Describes Issues That Led to 2023 Ethylene Oxide Release, Explosion

In July 2023, a release of EtO caused an explosion and fire at a Dow Chemical plant in Plaquemine, Louisiana. No one was killed or seriously injured, but the incident damaged process equipment and prompted local officials to declare a shelter-in-place order. The Chemical Safety and Hazard Investigation Board determined that a mechanical failure allowed EtO to leak into pressure relief piping, mix with air, and ignite. The flame traveled through piping to a drum containing EtO, which exploded. Among the safety issues CSB noted in its report was a failure to maintain an inert atmosphere of nitrogen in the pressure piping.

Most read in the digital Synergist:

Tracking Changes to the Purple Book: GHS Revision 11 and the Future of the Subcommittee of Experts

The Purple Book—the unofficial name for the GHS—is now on its 11th revision. While the hazard communication systems in most countries are at least a few revisions behind, they will eventually catch up, so now is the time to become familiar with the latest changes. These include the additions of guidance on how to address simple asphyxiants and communicate their hazards on safety data sheets, and the classification of substances and mixtures that contribute to global warming. The authors also warn that budget cuts at the United Nations threaten the work of the committee that oversees the GHS.

Most read on SynergistNow:

Everyday Networking

Technical acumen is essential in occupational and environmental health and safety. But so is networking, which requires a special kind of expertise that may be more difficult to develop than technical skill. Networking, the building of relationships, requires overcoming fears of rejection. This post presents the perspectives of two OEHS professionals who are leading an educational session titled “Networking for Scientists” at AIHA Connect 2026 that will provide strategies and tips for making connections with other professionals.

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