Contaminants of emerging concern (CECs) are not commonly monitored in the environment, but they can enter the environment from a variety of sources. The most worrying consequence of their wide use and environmental diffusion is the increase in the possible exposure pathways for humans. Moreover, knowledge of their behavior in the environment, toxicity, and biological effects is limited or not available for most CECs. The aim of this work is to edit the state of the art on few selected CECs having the potential to enter the soil and aquatic systems and cause adverse effects in humans, wildlife, and the environment: bisphenol A (BPA), nonylphenol (NP), benzophenones (BPs), and benzotriazole (BT). Some reviews are already available on BPA and NP, reporting about their behavior in surface water and sediments, but scarce and scattered information is available about their presence in soil and groundwater. Only a few studies are available about BPs and BT in the environment, in particular in soil and groundwater. This work summarizes the information available in the literature about the incidence and behavior of these compounds in the different environmental matrices and food. In particular, the review focuses on the physical-chemical properties, the environmental fate, the major degradation byproducts, and the environmental evidence of the selected CECs.

No abstract

Some studies show how exposure to fields can enhance or reduce cell activity, with possible applicative consequences in the field of biotechnology, including biological techniques for depollution. In order to identify full-scale conditions that are suitable and potentially applicable for use in electromagnetic fields to stimulate and accelerate bioremediation processes, this paper offers an examination of the scientific literature that is available on the effects of fields on microorganisms, and a critical analysis of it. The biological effects at times contrast with each other.

Biobarriers (BBs) are a new type of in situ technology for the remediation of contaminated groundwater. In recent years, this remediation technique has been more and more used in place of traditional Pump & Treat systems or other in situ technologies both in the USA and Europe. This work reviews the main experiences of BBs. The literature contains reports about tests and application at different scales (laboratory, pilot and full scale), which have been analyzed according to the aim of the study, the operative conditions adopted, the filling material, the inoculation procedure, the electron acceptor and the nutrient delivery systems. Operative conditions were extremely varied. Lab scale experiments pointed out good results in terms of pollutant removal efficiency. Pilot scale tests and full-scale applications confirmed the results obtained at lab scale, but also pointed out the importance of design for a proficient remediation system. The experiences underlined some possible critical issues: (a) the filling material must ensure proper hydraulic properties, but it also must be capable of keeping biomass in the reactive zone; (b) inoculation is a critical step and measurements should be carried out to check the initial distribution of microorganisms and its evolution over time; (c) electron acceptor and nutrient supply is usually required, but oxygenation into anaerobic aquifers can be critical.

No abstract