The effects of subchronic exposure to NeemAzal T/S on zebrafish (Danio rerio)

The objective of the study was to investigate the subchronic effects of the insecticidal preparation NeemAzal T/S at concentrations of 3, 10 and 30?mg/L on the mortality, growth and histopathology of juvenile zebrafish (Danio rerio), as well as its related effects on selected indices of oxidative stress during a 28-day toxicity test. The juvenile growth toxicity test was performed according to OECD Guidelines 215 (Fish, Juvenile Growth Test). The results of this study indicate that these tested concentrations of NeemAzal T/S (containing 1% of the active ingredient azadirachtin A) affect fish growth and have a negative influence on the indices of oxidative stress in the juvenile stage of zebrafish, as well as cause mild histopathological changes in liver tissue.     

Impact of source segregation intensity of solid waste on fuel consumption and collection costs

Fuel consumption and collection costs of solid waste were evaluated by the aid of a simulation model for a given collection area of a medium-sized Italian city. Using the model it is possible to calculate time, collected waste and fuel consumption for a given waste collection route. Starting from the data for the current waste collection scenario with a Source Segregated (SS) intensity of 25%, all the main model error evaluated was ?1.2. SS intensity scenarios of 25%, 30%, 35% and 52% were simulated. Results showed an increase in the average fuel consumed by the collection vehicles that went from about 3.3 L/tonne for 25% SS intensity to about 3.8 L/tonne for a SS intensity of 52%. Direct collection costs, including crews and vehicle purchase, ranged from about 40 €/tonne to about 70 €/tonne, respectively, for 25% and 52% SS intensity. The increase in fuel consumption and collection costs depends on the density of the waste collected, on the collection vehicle compaction ratio and on the waste collection vehicle utilization factor (WCVUF). In particular a reduction of about 50% of the WCVUF can lead to an average increase of about 80% in fuel consumption and 100% in collection costs.     

Urban Mining: Quality and quantity of recyclable and recoverable material mechanically and physically extractable from residual waste

The mechanically sorted dry fraction (MSDF) and Fines (<20 mm) arising from the mechanical biological treatment of residual municipal solid waste (RMSW) contains respectively about 11% w/w each of recyclable and recoverable materials. Processing a large sample of MSDF in an existing full-scale mechanical sorting facility equipped with near infrared and 2-3 dimensional selectors led to the extraction of about 6% w/w of recyclables with respect to the RMSW weight. Maximum selection efficiency was achieved for metals, about 98% w/w, whereas it was lower for Waste Electrical and Electronic Equipment (WEEE), about 2% w/w. After a simulated lab scale soil washing treatment it was possible to extract about 2% w/w of inert exploitable substances recoverable as construction materials, with respect to the amount of RMSW. The passing curve showed that inert materials were mainly sand with a particle size ranging from 0.063 to 2 mm. Leaching tests showed quite low heavy metal concentrations with the exception of the particles retained by the 0.5 mm sieve. A minimum pollutant concentration was in the leachate from the 10 and 20 mm particle size fractions.