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1.
J Anal Appl Pyrolysis ; 170: 105870, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36686287

RESUMO

During the COVID-19 pandemic, the world saw an exponential surge in the production of Personal Protective Equipment (PPE) kits, which eventually got discarded in the biomedical waste stream. In this study, thirteen different polymer samples from the PPE kit were collected and characterized using Fourier transform infrared spectrometer, thermogravimetric analysis, and analytical pyrolysis-gas chromatograph/mass spectrometry. The characterization data showed that about 94 % by mass of components were made of only three polymers, viz. polypropylene (PP, 75.6 wt %), polyethylene terephthalate (PET, 12.5 wt %), and polycarbonate (PC, 6 wt %). The analytical pyrolysis of the PPE coverall suit (PP) yielded mainly alkenes containing 2,4-dimethyl-1-heptene as the major compound with 17 wt % yield at 600 °C. The pyrolysates from face shield (PET) were rich in benzoic acid (5.8 wt %) and acetophenone (4.8 wt %), while those from safety goggles (PC) were rich in phenol (17.6 wt %) and p-cresol (12.4 wt %) at 600 °C. HZSM-5 and HY zeolites were used for the catalytic upgradation of pyrolysates especially from PP, PET and PC. The temperature and feed-to-catalyst ratio were optimized by performing catalytic fast pyrolysis experiments at 500 °C, 600 °C and 700 °C with different feed-to-catalyst ratios 1:2, 1:4, and 1:6 (w/w). The yield of aromatic hydrocarbons, viz., BTEX (benzene, toluene, ethylbenzene, xylenes) and naphthalene, was maximum (∼25.7 wt %) from PP coverall when HY catalyst was used at 600 °C and 1:6 (w/w) loading. In the case of PET face shield, the total yield of BTEX, naphthalene and biphenyl was maximum (27.9 wt %) at 600 °C and 1:4 (w/w) of HZSM-5, while in the case of PC goggles, it was maximum (18.6 wt %) at 700 °C and 1:4 (w/w) of HY. This study shows that the entire PPE kit can be valorized via catalytic fast pyrolysis to generate petrochemical products and platform molecules like monoaromatic hydrocarbons at high selectivities.

2.
Mater Today Proc ; 72: 1618-1623, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36213622

RESUMO

During this pandemic, it has become customary to wear a face waste mask to guard against coronavirus illness (COVID-19). However, huge production of face waste masks, PPE kit and gloves pose environmental risks, since existing disposal methods such as incineration and reclamation which are emitting hazardous substances. In the present study covid-19 medical waste material like waste face waste masks; gloves and PPE kit (personal protective equipment) are considered as the feedstock for the thermal degradation process. Mainly nylon, polyethylene and polypropylene compounds are present in the Covid-19 medical waste compounds, further feedstock material is subjected to physical characterization process like proximate, ultimate and thermo gravimetric analysis (TGA), to determine the moisture, ash, volatile matter and decomposition temperature respectively. The waste waste mask has lower ash content of 9.7 %, whereas gloves and other PPEs has 11.8 and 11.2 % of ash respectively. Similarly volatile matter is also higher for waste waste mask than other feed stocks. Pyrolysis process is carried out between a temperature range of 100 °C to 700 °C and the products of the pyrolysis process are pyrolytic liquid, gas and residue. The maximum pyrolytic oil is produced from waste masks, gloves and other PPE kit at 300, 350 and 320 °C respectively. The calorific value of the pyrolytic oil from waste mask, gloves and other PPE kit possess 40.85,40.11,40.31 MJ/kg respectively, which indicates that all the pyrolytic oil has closer to the diesel fuel. Therefore pyroltic oil obtained from the Covid-19 medical waste can be used as an alternative fuel for CI engine.

3.
J Family Med Prim Care ; 11(7): 3499-3503, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36387696

RESUMO

Background: Coronavirus disease (COVID-19) pandemic had an unprecedented effect on eye care services. The present study was conducted to assess the varied eye diseases and care around COVID-19 pandemic. Methods: This retrospective study was conducted at BBMCH, Balangir, Ophthalmology Department, Western Odisha, from September 2019 to May 2021 in three phases (i.e., September 2019 to March 2020, April to October 2020, November 2020 to March 2021). The total OPD consultations and emergency eye surgeries conducted around the COVID-19 period were retrieved from direct attendance in the OPD register, references, or tele-consultation. Results: Cumulative OPD eye consultations were found to be 13000, 3700, 7200 in pre-COVID, COVID and post-COVID period, respectively. Marked decrease in OPD cases (70%) was noticed in peak COVID period (April 2020 to October 2020) followed by slight increase during November 2020 to May 2021 i.e., (40% decrease). Allergic conjunctivitis was the commonest presentation in pre-COVID era, as compared to refractive error in COVID period. In post-COVID period, referrals, follow up cases, pending old surgical cases, red eyes formed major chunk of OPD attendance. Only 30% emergency cases underwent surgery during peak COVID, (Trauma cases, lens induced glaucoma, hypermature cataract, MLC cases, and one-eyed patients). But during post-COVID period this rose to 60%. Eight pediatric patients with intracorneal foreign body were given urgent treatment. Conclusion: Due to government guidelines and lockdown restrictions, majority (65%) of patients could not receive adequate treatment. But relaxation of rules in post-COVID period increased patient load to 75%.

4.
Environ Sci Pollut Res Int ; 28(40): 55811-55845, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34480299

RESUMO

The unforeseen outbreak of the COVID-19 epidemic has significantly stipulated the use of plastics to minimize the exposure and spread of the novel coronavirus. With the onset of the vaccination drive, the issue draws even more attention due to additional demand for vaccine packaging, transport, disposable syringes, and other allied devices scaling up to many million tonnes of plastic. Plastic materials in personal protective equipment (PPE), disposable pharmaceutical devices, and packaging for e-commerce facilities are perceived to be a lifesaver for the frontline healthcare personnel and the general public amidst recurring waves of the pandemic. However, the same material poses a threat as an evil environmental polluter when attributed to its indiscriminate and improper littering as well as mismanagement. The review not only highlights the environmental consequences due to the excessive use of disposable plastics amidst COVID-19 but also recommends mixed approaches to its management by adopting the combined and step-by-step methodology of adequate segregation, sterilization, sanitization activities, technological intervention, and process optimization measures. The overview finally concludes with some crucial way-forward measures and recommendations like the development of bioplastics and focusing on biodegradable/bio-compostable material alternatives to holistically deal with future pandemics.


Assuntos
COVID-19 , Humanos , Pandemias , Plásticos , SARS-CoV-2 , Vacinação
5.
Indian J Radiol Imaging ; 31(4): 893-900, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35136502

RESUMO

Background Due to long working hours wearing an N95 mask and PPE kit during the COVID-19 pandemic, the healthcare workers (HCWs) complained of headaches, confusion, and exhaustion. This study was therefore performed to study the changes in brain oxygenation. Aim To compare brain oxygenation in health care workers wearing an N95 mask with a PPE kit versus a three-ply mask during an intensive care setting for 6 hours. Materials and Methods Thirty clinicians and 30 paramedical staff participated in the study. The control (three-ply mask) and subject (N95 mask with PPE) groups included 15 clinicians and 15 paramedical staff. A comparative analysis of brain oxygenation using a 3T magnetic resonance imaging (MRI) machine was performed in these two groups at the beginning and the end of their work shift. Results The mean age of the individuals in the control and subject groups was 30.8 and 30.13 years, respectively. The median value of brain oxygenation in the control and subject groups in the pre-shift was between 33 and 31 and post-shift was 30 and 24. The drop in brain oxygenation in subjects was more than the controls ( p = 0.004) in the post-shift assessments. The cerebral blood flow (CBF) in the bilateral middle cerebral artery (MCA) using arterial spin labeling (ASL) showed a rise in CBF in both groups post-shift as compared with the pre-shift values. The median values of the right and left MCA in the control and subject groups pre-shift were 82.75/83.45 and 89.75/106.65. The post-shift median values of both MCAs of the control and subject groups were 115.65/115.55 and 109.60/119.49. Conclusion MRI-BOLD imaging revealed a significant drop in brain oxygenation in the subject group as compared with the control group. Multiphasic-ASL showed a compensatory rise in CBF in both groups.

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