Occurrence and removal of triclosan in Canadian wastewater systems.

Triclosan (TCS) is an antimicrobial agent used in many personal care and cleaning products. It has been detected in most environmental compartments and the main entry pathway is wastewater effluents and biosolids. TCS was analyzed in 300 samples of raw influent, final effluent, and biosolids from 13 wastewater treatment plants (WWTPs) across Canada representing five types of typical wastewater treatment systems. TCS was almost always detected in influent (median 1480 ng/L), effluent (median 107 ng/L), and biosolids (median 8000 ng/g dry weight) samples. Removals of TCS from lagoons as well as secondary and advanced treatment facilities were significantly higher than primary treatment facilities (p < 0.001). TCS removal was strongly correlated with organic nitrogen removal. TCS removals at most lagoons and plants that use biological treatment were higher during summer compared with winter. However, no seasonal or temperature effects were observed at the two primary facilities, likely due to the absence of biological activity. Aerobically digested solids contained the lowest levels (median 555 ng/g) while anaerobically digested primary solids contained the highest levels of TCS (median 22,700 ng/g). The results of this large comprehensive study demonstrate that TCS is consistently present in wastewater and biosolids at relatively high concentrations and that removal from wastewater and levels in biosolids are strongly influenced by the wastewater and solids treatment types.

Antioxidant activity of an ethnobotanically important plant Quisqualis indica Linn.

The antioxidant potential of leaf, stem, root and flower extracts of Quisqualis indica Linn. was assessed to verify its ethnopharmacological importance. Both polar and non-polar solvents like n-hexane, chloroform, ethanol and distilled water were used to obtain crude extracts. The chloroform extract of leaves showed the maximum %age yield, i.e. 27.3% while the n-hexane extract of stem showed the minimum yield, i.e. 0.2%. Five activities including DPPH free radical scavenging activity, ABTS+ assay, Total flavonoid components (TFC), Total phenolic components (TPC) and Metal chelating Assay (MC) were employed to evaluate the antioxidant activity of the plant. The ethanol extract of inflorescence of the plant displayed most elevated DPPH potential, i.e. 452.11%. Aqueous extract of root had highest value of TEAC i.e., 7.4515 mmol. The aqueous extract of flower displayed the highest level of phenolic contents with the value of 35 in terms of GAE mg/mL. On the other hand, the chloroform extract had the highest % bound iron value of 128 and the aqueous extract of flower showed a high concentration of Flavonoids having the value 347.65mg/l of Quercetin. It has been inferred that all parts of Quisqualis indica L. possess good antioxidant potential. Differents parts showed different antioxidant potentials hence they can be used as curative agents against human and animal ailments.