Methodologies for the collection of parameters to estimate dust/soil ingestion for young children.

Background: Heavy metals, pesticides and a host of contaminants found in dust and soil pose a health risk to young children through ingestion. Dust/soil ingestion rates for young children can be estimated using micro-level activity time series (MLATS) as model inputs. MLATS allow for the generation of frequency and duration of children's contact activities, along with sequential contact patterns.

Quantitative microbial risk assessment (QMRA) tool for modelling pathogen infection risk to wastewater treatment plant workers.

Wastewater treatment plants (WWTPs) provide vital services to the public by removing contaminants from wastewater prior to environmental discharge or reuse for beneficial purposes. WWTP workers occupationally exposed to wastewater can be at risk of respiratory or gastrointestinal diseases. The study objectives were to: (1) quantify pathogens and pathogen indicators in wastewater aerosols near different WWTP processes/unit operations, (2) develop a QMRA model for multi-pathogen and multi-exposure pathway risks, and (3) create a web-based application to perform and communicate risk calculations for wastewater workers.

Barriers to COVID-19 Intervention Implementation in K-5 Classrooms: A Survey of Teachers from a District with Mask Mandates despite a Statewide Mask Mandate Ban.

Unlabelled: The study objective was to characterize K-5 teachers' risk perceptions and experiences with CDC COVID-19 classroom guidance in an Arizona school district with a mask mandate, conflicting with a statewide mask mandate ban.

Methods: Public school teachers ( = 111) were recruited between 14 December 2021, and 31 January 2022, for an anonymous online survey with questions on seven important topics related to: (1) population demographics, (2) teachers' perceptions of COVID-19 in the workplace, (3) masks, (4) physical distancing, (5) surface transmission routes, (6) air flow, and (7) contact tracing protocols. Descriptive statistics were calculated, and statistically significant differences in categorical responses by grade level taught were investigated with Fisher's exact test.