Sewage sludge-based adsorbents: a review of their production, properties and use in water treatment applications.

Financial support from the Spanish Government (CTQ2009-
13699, CTQ2009-13459-C05-03/PPQ, RIRRAF RETICS), and
the Generalitat Valenciana (Prometeo Program) is gratefully
acknowledged. Dedicated to Prof. Avelino Corma on the occasion of his 60th birthday.

Organic photocatalysts for the oxidation of pollutants and model compounds.

Water pollution due to effluents from textile dyeing industry is a cause of serious concern. The techniques for detection of dyes are cost intensive and futile because the dyes undergo chemical changes under environmental conditions and the transformation products may be more toxic and carcinogenic than the parent molecule. Hence instead of detecting each chemical individually it is advisable to study the toxic effect of the effluents on various living organisms. Various techniques of toxicity and carcinogenicity measurements are discussed in this review. Remediation using physical, chemical and biological methods has also been critically reviewed.

Pollution due to synthetic dyes toxicity & carcinogenicity studies and remediation

The roles of free ammonia (FA) in biological wastewater treatment processes: A review.

A wide range of pharmaceuticals and personal care products (PPCPs) are present in the environment, and many of their adverse effects are unknown. The environmental risk assessment of 26 PPCPs of relevant consumption and occurrence in the aquatic environment in Spain was accomplished in this research. Based on the ecotoxicity values obtained by bioluminescence and respirometry assays and by predictions using the US EPA ecological structure–activity relationship (ECOSAR™), the compounds were classified following the Globally Harmonized System of Classification and Labelling of Chemicals. According to the criteria of the European Medicines Agency, the real risk of impact of these compounds in wastewater treatment plants (WWTPs) and in the aquatic environment was predicted. In at least two ecotoxicity tests, 65.4 % of the PPCPs under study showed high toxicity or were harmful to aquatic organisms. The global order of the species’ sensitivity to the PPCPs considered was as follows: Vibrio fischeri (5 min) > Vibrio fischeri (15 min) > algae > crustaceans > fish > biomass of WWTP. Acetaminophen, ciprofloxacin, clarithromycin, clofibrate, ibuprofen, omeprazole, triclosan, parabens and 1,4-benzoquinone showed some type of risk for the aquatic environments and/or for the activated sludge of WWTPs. Development of acute and chronic ecotoxicity data, the determination of predicted and measured environmental concentrations of PPCPs, the inclusion of metabolites and transformation products and the evaluation of mixtures of these compounds will allow further improvements of the results of the ERAs and, finally, to efficiently identify the compounds that could affect the environment.

Shijin Ren

Papers

Assessing wastewater toxicity to activated sludge: recent research and developments