Fate of microfibres from single-use face masks: Release to the environment and removal during wastewater treatment.

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.

Effects of long exposure to low temperatures on nitrifying biofilm and biomass in wastewater treatment.

Attached growth biological treatment systems are a promising solution to ammonia removal in cold-temperature climates. Environmental scanning electron microscopy (ESEM) and confocal laser scanning microscopy in combination with fluorescent in situ hybridization (FISH) was used to investigate the effects of 4 months of exposure to 4 degrees C on nitrifying biofilm and biomass. These molecular and microscopic methods were modified to minimize loss of mass and distortion of in situ perspectives.

Photo-removal of sulfamethoxazole (SMX) by photolytic and photocatalytic processes in a batch reactor under UV-C radiation (λmax=254 nm).

In this study, photolytic and photocatalytic removal of the antibiotic sulfamethoxazole (SMX) under UVC radiation (λ=254 nm) was investigated. The light intensity distribution inside the batch photoreactor was characterized by azoxybenzene actinometry. The intensity of incident radiation was found to be a strong function of position inside the reactor.

In situ characterization of nitrifying biofilm: minimizing biomass loss and preserving perspective.

Methods for characterizing nitrifying bacteria within biofilms are of key importance to understand and optimize the nitrification kinetics of attached growth treatment facilities. In this work, we propose an analytical protocol based upon environmental scanning electron microscopy (ESEM) and confocal laser scanning microscopy (CSLM) in combination with fluorescent in situ hybridization (FISH) to characterize the structure of nitrifying biofilm as it remains attached to the original reactor substratum. This protocol minimizes the loss of mass and distortion of in situ perspective commonly associated with traditionally applied microscopic techniques and thereby enables a more accurate estimation of the nitrifying biomass within biofilm attached to the substratum.

Rapid and reliable quantification of biofilm weight and nitrogen content of biofilm attached to polystyrene beads.

Increased popularity of attached-growth wastewater treatment systems (e.g. biological aerated filtration processes-BAF) has created the need for a rapid and reliable method of characterizing biofilms.