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Objective: To 1) characterize the decay curve of infective SARS-CoV-2 over time on the surface of cardboard packaging and plastic mailer packaging; 2) characterize the transferability over time of virus-inoculated cardboard packaging and plastic mailer packaging to skin. Methods: We inoculated samples of plastic and cardboard packaging with a titer of SARS-CoV-2 > 10 6 TCID 50 / mL to evaluate the survivability and transferability to the skin (pig skin) over time. A cell culture-based infectivity assay (TCID 50 ) was used to determine viral titers. Regression analysis was used to characterize decay curves. Results: The time that SARS-CoV-2 remained transferable to skin was reduced on both packaging substrates compared to the total time of survivability, though cardboard demonstrated a substantially larger reduction. Virus inoculated plastic substrates continued to transfer the virus to the skin after 7 hours of holding time and regression analysis predicts this transferability would remain detectable up to 9.5 hours of holding time. Inoculated cardboard substrates demonstrated detectable transfer at 15 minutes of holding time, but no viable virus could be detected on the skin after 30 minutes of holding time. Conclusions: The type of material used as a packaging substrate substantially modifies the potential for SARS-CoV-2 fomite transmission. The use of materials that limit fomite transmission from packaging should be considered among strategies to reduce the transmission of SARS-CoV-2. Future research should investigate the generalizability of these findings for other viral pathogens that potentially transmit via fomite.

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Development and maintenance of mill- and wastewater treatment system-specific programs aimed at optimizing use of supplemental nutrients for purposes of minimizing residual nutrients in treated effluents have evolved in recent years and are summarized. Suggestions for monitoring of nutrient forms in wastewaters prior to and during biological treatment are presented, as are approaches for determining supplemental nutrient requirements, monitoring biomass characteristics, and achieving minimum nitrogen and phosphorus residuals in treated final effluents while maintaining targeted levels of biological treatment. Aspects of nutrient management relevant to activated sludge (AS) and aerated stabilization basin (ASB) systems are presented, and ASB configurations operated in part to minimize nutrient levels in treated effluents are highlighted.