Single-use face masks can release microfibres upon exposure to environmental conditions. This study investigates the number of microfibres released in the presence and absence of UV irradiation and mechanical friction and the removal of the released microfibres in a simulated conventional wastewater treatment process. UV exposure results in a four-fold increase in the number of microfibres released from new masks and used masks resulting in ~2400 microfibres/mask and ~1100 microfibres/mask, respectively. Application of mechanical friction to the UV-exposed new and used masks further increases the number of released microfibres per mask. In a simulated coagulation/flocculation process, the removals of microfibers originating from new masks and used masks are 79% and 91%, respectively. XPS analysis reveals that the silica content of the used masks is 240% higher than that of new masks, which could explain the higher removal efficiency of microfibers from used masks. FTIR analysis of the masks after UV exposure shows carbonyl indices of 0.73 ± 0.70 and 0.27 ± 0.10 for the microfibres from used and new masks, respectively. Based on available data, we estimate that 4-47 million polypropylene microfibres can be released into natural waters per day after wastewater treatment in an urban environment (for a population of 4300 persons/km).

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jhazmat.2022.129408DOI Listing

Publication Analysis

Top Keywords

masks
12
wastewater treatment
12
microfibres released
12
single-use face
8
face masks
8
masks release
8
number microfibres
8
mechanical friction
8
released microfibres
8
masks masks
8

Similar Publications

Introduction: Despite efforts by health organizations to share evidence-based information, fake news hindered the promotion of social distancing and vaccination during the coronavirus disease 2019 (COVID-19) pandemic. This study analyzed COVID-19 knowledge and practices in a vulnerable area in northern Rio de Janeiro, acknowledging the influence of the complex social and economic landscape on public health perceptions.

Methodology: This cross-sectional study was conducted in Novo Eldorado - a low-income, conflict-affected neighborhood in Campos dos Goytacazes - using a structured questionnaire, following the peak of COVID-19 deaths in Brazil (July-December 2021).

View Article and Find Full Text PDF

Introduction: Significant challenges to implementing international health regulations (IHR) at points of entry (PoEs) have been highlighted by the coronavirus disease 2019 (COVID-19) pandemic. Better assessment of the capacities of the PoEs may promote focused interventions. This study aimed to assess the capacities and practices at PoEs.

View Article and Find Full Text PDF

We aimed to build a robust classifier for the MGMT methylation status of glioblastoma in multiparametric MRI. We focused on multi-habitat deep image descriptors as our basic focus. A subset of the BRATS 2021 MGMT methylation dataset containing both MGMT class labels and segmentation masks was used.

View Article and Find Full Text PDF

Although the Transformer architecture has established itself as the industry standard for jobs involving natural language processing, it still has few uses in computer vision. In vision, attention is used in conjunction with convolutional networks or to replace individual convolutional network elements while preserving the overall network design. Differences between the two domains, such as significant variations in the scale of visual things and the higher granularity of pixels in images compared to words in the text, make it difficult to transfer Transformer from language to vision.

View Article and Find Full Text PDF

Background: Adalimumab is an effective treatment for juvenile idiopathic arthritis-associated uveitis. Data are scarce on the effects of discontinuing adalimumab after control of the disease had been reached. We aimed to assess efficacy and safety of discontinuing treatment in patients with juvenile idiopathic arthritis-associated uveitis.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!