Nanoplastics (NPs) are generated from the fragmentation of microplastics (MPs) through mechanical forces such as mixing, sonication and homogenization in wastewater treatment plants (WWTPs). Despite their environmental significance, the formation mechanisms and size distribution of NPs in WWTPs are not well understood. This study presents an in-depth investigation into the fragmentation mechanisms of polyethylene (PE) and polystyrene (PS) MPs, sized 250 μm and 106 μm, under simulated WWTP conditions.
View Article and Find Full Text PDFWastewater treatment plants (WWTPs) are major recipients of microplastics (MPs) that break down into nanoplastics (NPs) during wastewater treatment through physical, chemical, and biological processes. In particular, mechanical stress induced by the mixing process commonly used in WWTPs is thought to play a crucial role in the production of secondary MPs/NPs, which are then discharged into the open water environment through the WWTP effluent. This study investigated the fragmentation of 250 and 106 μm-sized pristine and weathered polystyrene (PS) particles using a four-blade mechanical impeller.
View Article and Find Full Text PDFNano/microplastic (NP/MP) pollution is a growing concern for the water environment. Wastewater treatment plants (WWTPs) are considered the major recipients of MP before discharging into local waterbodies. MPs enter WWTPs mainly from synthetic fibers through washing activities and personal care products.
View Article and Find Full Text PDFMicroplastics (MP) have become a major emerging class of pollutants representing significant eco-toxicological risks for ecosystems and marine environments. The aim of this study was to identify, classify and quantify MP present in both road dust and stormwater samples. A significantly higher level of MPs within road dust samples was detected from industrial area (1130 particles/kg of dust) than from residential area (520 particles/kg of dust), while stormwater samples from industrial and residential sites yielded 26 particles/L and 17 particles/L, respectively.
View Article and Find Full Text PDFNano/microplastics (NPs/MPs), a tiny particle of plastic pollution, are known as one of the most important environmental threats to marine ecosystems. Wastewater treatment plants can act as entrance routes for NPs/MPs to the aquatic environment as they breakdown of larger fragments of the plastic component during the treatment process; therefore, it is necessary to remove NPs/MPs during the wastewater treatment process. In this study, understanding the effect of water shear force on the fragmentation of larger size MPs into smaller MPs and NPs and their removal by air flotation and nano-ferrofluid (i.
View Article and Find Full Text PDFSignificance: This study explains the construction and validation of a chart in Hindi language, one of the commonly spoken languages in the world. The new visual acuity chart is called LEA Hindi chart. The calligraphy construction method described here can help develop other such acuity charts.
View Article and Find Full Text PDFPurpose: To identify the referral pattern and identify causes of missed referrals to low-vision services in a tertiary eye care center.
Methods: A retrospective review of all the hospital records of patients seen from September-December 2012 was done to identify patients with visual impairment. Low vision was defined as has a best-corrected visual acuity (BCVA) in the better eye of <20/60 to light perception (as per WHO definition); or a visual field of <20° from the point of fixation.
J Ophthalmic Inflamm Infect
February 2014
Background: Ocular tuberculosis (TB) can affect nearly every ocular tissue, leading to a variety of vision-threatening clinical manifestations. The goal of this study is to estimate the degree, duration, and causes of visual impairment in eyes affected by ocular TB.
Results: This was a retrospective study of patients diagnosed as ocular TB based on polymerase chain reaction (PCR) for Mycobacterium tuberculosis complex.