Optimization and validation of ultrasound application with a low-temperature method to analyze organochlorine pesticides in smuggled cigarette tobacco.

This work presents the optimization and validation of a method to quantify organochlorine pesticides in tobacco samples from smuggled cigarettes using ultrasound application and low-temperature extraction. The combined approach was validated for 20 organochlorine pesticides, achieving recoveries between 73% and 116%, and a relative standard deviation of less than 20%. The method minimized the matrix effect in 65% of the organochlorine pesticides.

Phytotoxicity indexes and removal of color, COD, phenols and ISA from pulp and paper mill wastewater post-treated by UV/HO and photo-Fenton.

Pulp and paper mill wastewater (PPMWW) contains high concentrations of recalcitrant compounds that cause toxicity to organisms. Advanced oxidation processes (AOPs) have the ability to degrade these compounds and reduce overall toxicity. Physicochemical characterization and Lactuca sativa toxicity test were conducted to compare the effectiveness of two post-treatments: UV/HO and photo-Fenton.

Post-treatment of anaerobic reactor effluent using coagulation/oxidation followed by double filtration.

This study evaluates the efficacy of a sanitary sewage treatment system, proposing post-treatment of the effluent generated by the upflow anaerobic sludge blanket UASB reactor, through a Fenton coagulation/oxidation ((ferric chloride (FC) or ferrous sulfate (FS) and peracetic acid (PAA)), followed by a double filtration system, composed of a gravel ascending drainage filter and a sand descending filter. Following the assessment of treatability, the system efficiency was evaluated using physicochemical and microbiological parameters. In all treatments performed in the pilot unit, total suspended solids (TSS) were completely removed, leading to a decrease in turbidity greater than 90% and close to 100% removal of total phosphorous.

Synergism effects for Escherichia coli inactivation applying the combined ozone and chlorine disinfection method.

Water disinfection assays were carried out using ozone and chlorine in non-sequential steps--the individual method--and in sequential steps--the combined ozone/chlorine method. Escherichia coli strain ATCC 11229 was used as the indicator microorganism. For the assays using the individual method, the applied dosages of ozone were 2.