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Persistent Organic Pollutants (POPs) in water can reach levels below ppt (ng L−1), representing a challenge for risk assessment using long-term exposure. Therefore, sampling devices to monitor trace levels of organic compounds are suitable due to their sensitivity and low detection limits. In this work, the field calibration and monitoring for POPs, such as Polycyclic Aromatic Hydrocarbons (PAHs) and pesticides, in a drinking water reservoir were carried out using semipermeable membrane devices (SPMDs). The SPMDs were spiked with deuterated PCBs used as PRCs, and their dissipation was measured at 5, 10, 15 and 24 days. The SPMDs were dialyzed in hexane twice and the initial amount (N) and final amount (No) of PRCs in extracts were estimated by GC/MS to calculate the sampling rate (Rs) for target compounds. The PCBs were dissipated more than 30% at 24 days, and Rs were calculated between 27.8 and 72.7 L day−1 for PAHs and 35.8 and 71.3 L day−1 for pesticides. Finally, PAH congeners such as Naphthalene, Acenaphthylene, Acenaphthene, Fluorene, Phenanthrene, Anthracene, Fluoranthene and Pyrene were detected at water concentration (Cw) ranges between 0.5 and 2.7 ng L−1, whilst chlorpyrifos was the only pesticide detected at 19.0 ng L−1 in the reservoir. This calibration showed that PRCs do not dissipate entirely in 24 days and that dissipation modelling may be applied for Cw estimation of POPs in reservoirs.

Many differrent solid wastes are deposited in landfills which may lead to leaching processes with groundwater pollution implications. Complex fractions of organic pollutants may transfer from the soil with multiplex physicochemical interactions which reduce the final soil-borne. In this paper, we study the potential removal of a dye and the potential of water infiltration in each layer of a soil. The results show a removal >98% in the complete profile and in the silty layer (SL) in which more infiltration was found. Therefore, organic fraction in the SL and even more interaction with the aluminum and silicates present, may reduce the dye by physicochemical interaction with log Koc properties. Also, more infiltration in SL indicates a strong interaction between dissolve analytes and soil due to despite a large amount of water cross the silt, low infiltered levels is presented. Finally, pH slightly acid from 4.5 in the sample was increased to 6.7 which indicates basic condition for neutralization, while conductivity was reduced even to values presented in tap water due to ionic exchange capacity by the soil. A preliminary conclusion indicates that removal of the first layer in a landfill reduces the capacity of pollutants removal in soils and, therefore, low physicochemical interactions may lead to the leaching of pollutants to waterbodies. However, further experiments are needed to strengthen this study.ResumenMuchos residuos solidos son depositados en rellenos sanitarios, lo que puede conducir a procesos de lixiviacion con implicaciones de contaminacion del agua subterranea. Las fracciones complejas de contaminantes organicos pueden transferirse desde el suelo con una interaccion fisicoquimica que reduce su paso final al agua. En este trabajo, se evaluo la eliminacion de un colorante y el potencial de la infiltracion del agua en cada estrato de un suelo. Los resultados muestran una eliminacion > 98% en el perfil completo del suelo y en el estrato limoso (SL) en el que se encontro mas infiltracion. Por lo tanto, la fraccion organica en el SL y la interaccion con el aluminio y lossilicatos presentes, pueden reducir el colorante por interacciones fisicoquimicas con propiedades de log Koc. Ademas, una mayor infiltracion en SL indica una fuerte interaccion entre el colorante y el suelo debido a que, aunque una gran cantidad de agua atraviesa los limos, se presentan bajos niveles infiltrados del colorante. Finalmente, el pH ligeramente acido de 4,5 en la muestra se incremento a 6,7 lo que indica una condicion basica para la neutralizacion, mientras que la conductividad se redujo incluso a los valores presentados en el agua del grifo debido a la capacidad de intercambio ionico del suelo. Una conclusion preliminar muestra que la eliminacion del primer estrato en un relleno sanitario reduce la capacidad de eliminacion del suelo y, por lo tanto, pocas interacciones fisicoquimicas pueden llevar a la lixiviacion de contaminantes a cuerpos de agua. Sin embargo, deben llevarse a cabo mas estudios en el futuro. https://doi.org/10.22209/rt.v43n2a04

Air pollution is an important cause of non-communicable diseases globally with particulate matter (PM) as one of the main air pollutants. PM is composed of microscopic particles that contain a mixture of chemicals and biological elements that can be harmful to human health. The aerodynamic diameter of PM facilitates their deposition when inhaled. For instance, coarse PM having a diameter of

The presence of levonorgestrel (LNG) in water bodies via direct discharge and human excretion has been reported worldwide, but its effects on the reproduction of aquatic species and humans are still unknown. Owing to its recalcitrant properties, LNG is not completely removed during wastewater treatment plants, and many species may be exposed to low traces of this compound from discharged effluents. Thus, in this study, a photocatalytic process for removing LNG along with screening of endocrine disruptor effects for risk assessment was applied. Although the removal rate of LNG by ultraviolet C (UV-C) radiation was >90%, reproductive toxicity testing using the BeWo cell line exposed to LNG and its degraded fraction showed the reduced production of basal human chorionic gonadotropin hormone (β-hCG) by more than 73%, from 8.90 mIU mL-1 to