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Bisphenol A (BPA) is an anthropogenic chemical compound utilized to manufacture a wide range of consumer products, such as polycarbonate, polyvinyl chloride (PVC), food packages, and thermal papers. Because of its extensive worldwide use, BPA is pervasive in the environment, negatively affecting aquatic life. Therefore, we studied the occurrence, persistence, and ecological risk of BPA in surface water receiving raw leachate from a municipal solid waste (MSW) open dump in Kerawalapitiya, Sri Lanka. Our findings corroborate that the BPA average concentrations in the canal network were 0.4–42.6 µg/L during the wet season and 0.2–4.9 µg/L during the dry season. The levels of BPA at 11 locations (out of 16) during both seasons differed significantly from the upstream sample, where there was no impact from the dump site (p < 0.05), indicating the ubiquitous occurrence and persistence of BPA in the canal network. BPA levels in the waterbodies are greater in the wet period than in the dry period because of the continuous ingress of run‐off‐driven leachate to the canal network. Our study infers that pH and salinity correlate positively with BPA, while temperature, DO, and TSS are negatively correlated with BPA. BPA levels in five locations during the wet season and one during the dry season surpassed the tolerable level of BPA stipulated by the Canadian Federal Environmental Quality Guidelines to safeguard aquatic life, which is 3.5 µg/L. The findings of the acute ecological risk assessment articulate that during the wet season, Mozambique tilapia (Oreochromis mossambicus) and orange chromide (Etroplus maculatus) constitute a high acute risk, while they pose a medium acute risk during the dry season. Our study suggests that the relevant authorities must prevent the ingress of runoff rich with BPA onto the canal network to protect aquatic life. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the applications of Dentronics, the hypernym of a wide field of modern dental technologies which every dentist can embrace for the safe and uninterrupted provision of dental care. Topics discussed include state-of-the-art technology-embedded products and systems invented by scientists for dentistry, the need for standard dashboards and agreed policies to facilitate data sharing among stakeholders, and benefits of these devices to a dentist.

Fats, oils and grease (FOG) congregate in grease traps and are a slowly biodegradable particulate organic matter, which may require enzymatic or hydrolytic conversion to form readily biodegradable soluble organic matter. The existing treatment methods employ water-based hydrolysis of FOG to form long-chain fatty acids (LCFAs). The LCFAs discharged into wastewater treatment system create functional difficulties, especially the inhibitory effect caused by accumulation of LCFAs. This study aims to find an effective treatment method for this persistent problem encountered in conventional wastewater treatment system. Solid-state degradation by lipolytic fungi was performed in a tray-type reactor as a novel approach of bioaugmentation. Grease trap waste samples were dried to have moisture content of 25-35% and mixed with coir fiber (1% w/v) for proper aeration. Each 10 mg/g dry weight of substrate was inoculated with 1 mL of spore suspension (1 × 10⁷ spores/mL) of lipolytic fungi. Thereafter, moisture content in the reactor was increased to 65%, and incubated at 30°C. Within 72 h of post incubation, degradation efficiency of about 50% was recorded by fungal isolates. The feasibility of using developed protocol for FOG degradation was tested with a laboratory-scale prototype reactor. [ABSTRACT FROM AUTHOR]

This article reports the phytoremediation efficiencies of water hyacinth (Eichhornia crassipes (Mart.) Solms) grown under different nutritional conditions for Al rich wastewaters in batch type constructed wetlands (floating aquatic macrophyte-based plant treatment systems). This study was conducted for 15 weeks after 1 week acclimatization by culturing young water hyacinth (average height of 20 ± 2 cm) in 590 L capacity fiberglass tanks under different nutrient concentrations of 2-fold [56 and 15.4 mg/L of total nitrogen (TN) and total phosphorous (TP), respectively], 1-fold, 1/2-fold, 1/4-fold and 1/8-fold with synthetic wastewaters containing 5.62 Al mg/L. A control set-up of hyacinths comprising only Al with no nutrients was also studied. A mass balance was carried out to investigate the phytoremediation efficiencies and to identify the different Al removal mechanisms from the wastewaters. Chemical precipitation of Al(OH)3 was a dominant contribution to Al removal at the beginning of the study, whereas adsorption of Al3+ to sediments was observed to be a predominant Al removal mechanism as the study progressed. Phytoremediation mainly due to rhizofiltration was also an important mechanism of Al removal especially during the first 4 weeks of the study in almost all the set-ups. However, chemical precipitation and sediment adsorption of Al3 + was a dominant contribution to Al removal in comparison with phytoremediation. Plants cultured in the control set-up showed the highest phytoremediation efficiency of 63% during the period of the 4th week. A similar scenario was evident in the 1/8-fold set-up. Hence we conclude that water hyacinth grown under lower nutritional conditions are more ideal to commence a batch type constructed wetland treating Al rich wastewaters with a hydraulic retention time of approximately 4 weeks, after which a complete harvesting is recommended. [ABSTRACT FROM AUTHOR]

A response to a letter to the editor about the article "Removal of aluminium by constructed wetlands with water hyacinth (Eichhornia crassipes (Mart.) Solms) grown under different nutritional conditions" is presented.