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There are still substantial questions about whether protected areas affect the quality and biodiversity of surface waters within their borders. In this study, the size and land use of 19 protected areas of Latium Region (central Italy) were related to the biological quality of 32 streams running inside them. Additionally, the biological quality of 18 out of the 32 streams was compared with the quality recorded on the same streams outside the boundaries of the protected areas. The biological quality was assessed using the Extended Biotic Index, which indicates the macroinvertebrate community health. The quality of 32 study streams running through the protected areas was not related to the size of these areas, but it did reflect land use. On average, the 18 study sites inside protected areas had biological quality similar to external control sites. In the protected areas, the biological quality of streams was higher than for the same streams in the surrounding territory provided that anthropogenic changes were fewer. These data indicate that the creation of protected areas per se does not increase freshwater biodiversity and that land use has a major impact on the biological quality of the stream in a protected area. As a consequence, a higher number of reserves or landscape designations specifically created for aquatic conservation is necessary and recovery programs aimed at restoring physical habitats and reducing sources of impact to aquatic life have to be pursued. Also, where the anthropogenic impact is high (e.g., as in the case of strongly urbanised areas), the creation of effective protected areas might improve the biological quality of water courses.

This study was designed to improve the removal efficiency of COD, SS, and microorganism at the S. Giovanni a Teduccio municipal wastewater treatment plant, Naples, Italy. The plant consists of screen, sand grinder, oil removal, coagulation, flocculation and sedimentation units, hypochlorite disinfection, mechanical dewatering, and thermal sludge conditioning. A series of Jar-test was conducted on twelve samples taken after screen using FeSO4 alone or together with Ca(OH)2 at 100 rpm rapid mixing for 1 min, 30 rpm for slow mixing for 20 min and 30 min for settling. 150 mg L(-1) and 450 mg/L doses of FeSO4 were used at a pH interval in between 6 and 9. The removals of COD, TSS, Escherichia coli and total coliforms were measured ranging from 40 to 70%, 70 to 90%, 96 to 99% and 97 to 99%, respectively when FeSO4 was used alone at 150 mg L(-1) and 450 mg L(-1) doses and at pH 6, 7 and 8. Wastewater discharge standards could be safely obtained at 150 mg L(-1) dose of FeSO4 with the use of 220 mg L(-1) Ca(OH)2 at pH 8 in terms of COD and E. coli removals resulted in 65% and 98%, respectively, with less sludge production to be disposed. Additionally, none of influent and supernatant samples tested in this study was found to be acute toxic on 24h-born Daphnia magna at 50% dilution.

Urban wastewater treatment plant (UWWTP) effluents are among the possible sources of antibiotics and antibiotic-resistant bacteria (ARB) spread into the environment. In this work, the effect of UV radiation on antibiotic-resistant Escherichia coli (E. coli) strains was compared with that of chlorination process. Under the investigated conditions, UV disinfection process resulted in a total inactivation after 60min of irradiation (1.25×10(4)μWscm(-2)) compared to 120min chlorine contact time (initial chlorine dose of 2mgL(-1)). Moreover, no change in E. coli strains' resistance to amoxicillin (AMX) (minimum inhibiting concentration (MIC)>256mgL(-1)) and sulfamethoxazole (SMZ) (MIC>1024mgL(-1)) could be observed after UV treatment, while the treatment affected resistance of the lower resistance strain to ciprofloxacin (CPX) (MIC decreased by 33% and 50% after 60 and 120min, respectively). Contrarily, chlorination process did not affect antibiotic resistance of the investigated E. coli strains. Finally, the effect of UV radiation on the mixture of three antibiotics was also investigated and photodegradation data fit quite well pseudo first order kinetic models with t1/2 values of 14, 20 and 25min for CPX, AMX and SMZ, respectively. According to these results, conventional disinfection processes may not be effective in the inactivation of ARB, and the simultaneous release of ARB and antibiotics at sub-lethal concentrations into UWWTP effluent may promote the development of resistance among bacteria in receiving water.

The synthesis and photobiological activity of four new 4'-methyl derivatives of 5-MOP (5-methoxypsoralen) and 5-MOA (5-methoxyangelicin), i.e., 4,4'-dimethyl-5-methoxypsoralen, 3,4'-dimethyl-5-methoxypsoralen, 4,4'-dimethyl-5-methoxyangelicin, and 3,4'-dimethyl-5-methoxyangelicin, are described. All these compounds photobind efficiently to DNA. The DNA-photobinding process was investigated using various nucleic acid structures such as double-helix DNA, bacterial DNA, and synthetic polydeoxyribonucleotides. Photoreaction experiments showed that, unlike 8-MOP (8-methoxypsoralen) and 5-MOP, both angular derivatives bind thymine and cytosine with the same efficiency. The principal nucleoside-psoralen monoadducts were isolated and characterized after enzymatic digestion or acid hydrolysis. Biological activity studies revealed a good correlation with the extent of covalent photoaddition. Moreover, the two angular derivatives and the 4,4'-dimethyl-5-methoxypsoralen were unable to induce skin erythema, in striking contrast with the reference drugs, 8-MOP and 5-MOP; only the 3,4'-dimethyl-5-methoxypsoralen caused erythema, although to a substantially lower extent than that induced by the two parent compounds.