Laboratory safety teams (LSTs), led by graduate student and postdoctoral researchers, have been propagating across the U.S. as a bottom-up approach to improving safety culture in academic research laboratories. Prior to the COVID-19 pandemic, LSTs relied heavily on in-person projects and events. Additionally, committed Champions from the ranks of safety professionals and faculty were critical to their operation and continued expansion. As was the case for many existing systems, the COVID-19 global crisis served as an operational stress test for LSTs, pushing them to unexpected new limits. The initial spread of COVID-19 brought with it a shutdown of academic institutions followed by a limited reopening that prohibited in-person gatherings and disrupted standard lines of communication upon which LSTs relied. Safety professionals and faculty members were required to take on new duties that were often undefined and time-consuming, substantially impacting their ability to support LSTs. In this case study, we report the impact of this operational stress test on 12 LSTs, detailing the adaptive means by which they survived and highlighting the key lessons learned by the represented LST leaders. The key takeaways were to spend time nurturing relationships with a diverse array of Champions, securing stable funding from multiple sources, and networking with members of LSTs from different institutions to strengthen moral support and broaden ideation for common challenges.

Environmental films are atmospheric materials that passively deposit and form coatings on most outdoor surfaces. Film heterogeneity in the chemical makeup and physical form often makes understanding their contributions to the environment difficult. It is well known that cities or rural areas produce unique films. To study how this trend changes with a known distance, we characterize two films, collected at the same time, separated by ∼1 km: representing city (CB) and suburban (CP) areas. The chemical analysis shows that the urban (CB) film, in comparison to its suburban (CP) counterpart, has higher surface coverage (+4.8%) and higher elemental diversity in metals. The physical form and roughness show that the urban (CB) sample collects more particulate than the suburban (CP) sample. This accumulation increases the surface area suggesting that the urban (CB) sample forms faster and maintains higher adsorption capacity than the suburban sample. The urban (CB) sample has metals often associated with fireworks meaning that surfaces could act as a sink and source for metallic species impacting local ecosystems through rainwater wash-off. The urban samples discharge more of the accumulated material (inorganic and organic water-soluble species) when extracted with water (+2 μg/cm2). This means that urban sites, like buildings, contribute more to waste water pollution than the suburban sites, like houses. There is also potential for this contribution to be more harmful in urban areas. These findings have important applications in understanding air and water quality in urban and suburban areas.

As atmospheric particulate and (semi)volatile molecules gradually deposit on outdoor surfaces, they create heterogeneous coatings known as environmental films. The unique chemical environments within these films will impact local environmental chemistry. We report the effects of water vapor and deliquescence/efflorescence cycling on particles incorporated into these films within three model systems created in our laboratory: pure salt, pure organic, and mixed salt-organic films, ranging from 1 to 5 μm thickness. To do this, we monitor morphology changes to inorganic and organic particles that comprise each film type before and after relative humidity (%RH) cycling. We track the model film behaviors by quartz crystal microbalance and optical microscopy, including detailed image analysis to track particle sizes, shapes, and number density. Our results show maximum particle diameter and shape distributions (≥100 nmhundreds of μm and circular to elongated), as well as the number of film particles per unit area change in different ways depending on the composition of the model film. Specifically, the pure salt films show fewer, larger particles after %RH cycling. Pure organic films show a small decrease in particle sizes but no significant morphology changes. In mixed films of inorganic and organic species, the %RH exposure leads to matured films with higher numbers of smaller, more compact particles. Based on these observations, we suggest the effects of %RH on increasing mobility (mixing, lateral reach, and aggregation) of deliquesced or liquid-phase particles within the film. These maturation, or ripening, effects alter the capacity for environmental films to affect local environmental chemistry.

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Fungi are prevalent microorganisms in environmental films. Their impacts on the film chemical environment and morphology remains poorly defined. Here we present microscopic and chemical analyses fungi impacts to environmental films over long- and short-time scales. We report bulk properties of films accumulated for 2 months (February and March 2019) and 12 months to contrast short and longer-term effects. Bright field microscopy results show that fungi and fungal-associated aggregates cover close to 14% of the surface after 12 months and include significant numbers of large (tens to hundreds of μm in diameter) particles aggregated with fungal colonies. Data acquired for films accumulated over shorter times (2 months) suggest mechanisms that contribute to these longer-term effects. This is important because the film’s exposed surface will determine what additional material will accumulate over the ensuing weeks or months. A combination of scanning electron microscopy and energy dispersive X-ray spectroscopy provides spatially resolved maps of fugal hypha and nearby elements of interest. We also identify a “nutrient pool” associated with the fungal hypha which extend orthogonally to the growth direction to ca. 50 μm distances. We conclude that fungi have both short-term and long-term effects on the chemistry and morphology of environmental film surfaces. In short, the presence (or absence) of fungi will significantly alter the films’ evolution and should be considered when analyzing environmental film impacts on local processes.