The current study aimed at quantifying arsenic and lead in feathers from three passerine species that are residents from areas exposed to mining activities (Toxostoma curvirostre, Campylorhynchus brunneicapillus, and Melozone fusca). Lead and As contents in bird feathers and in superficial soil samples were measured with AAS. Levels of these metals were compared between sites exposed and unexposed to mining. Possible correlations of As and Pb between superficial soil and bird feathers were also investigated. Soil metal concentrations were significantly higher near mining sites, and metal concentrations in bird feathers showed a behavior similar to those recorded for soil samples. Individual birds from polluted sites had higher mean feather metal concentrations in comparison with non-polluted sites; no differences in metal concentrations were recorded among bird species. This work constitutes a basis for monitoring contaminants, and for future toxicological studies attempting to understand the impact that some mining activities may have on bird populations.

The Typha genus comprises plant species extensively studied for phytoremediation processes. Recently, Pseudomonas rhodesiae GRC140, an IAA-producing bacterium, was isolated from Typha latifolia roots. This bacterium stimulates the emergence of lateral roots of Arabidopsis thaliana in the presence and absence of cadmium. However, the bacterial influence on cadmium accumulation by the plant has not been determined. Moreover, the P. rhodesiae GRC140 effect in Cd phytoextraction by T. latifolia remains poorly understood. In this work, an axenic hydroponic culture of T. latifolia was established. The plants were used to evaluate the effects of cadmium stress in axenic plants and determine the effects of P. rhodesiae GRC140 and exogenous indole acetic acid (IAA) on Cd tolerance and Cd uptake by T. latifolia. Biomass production, total chlorophyll content, root electrolyte leakage, catalase activity, total glutathione, and Cd content were determined. The results showed that Cd reduces shoot biomass and increases total glutathione and Cd content in a dose-dependent manner in root tissues. Furthermore, P. rhodesiae GRC140 increased Cd translocation to the shoots, while IAA increased the Cd accumulation in plant roots, indicating that both treatments increase Cd removal by T. latifolia plants. These results indicate that axenic plants in hydroponic systems are adequate to evaluate the Cd effects in plants and suggest that T. latifolia phytoextraction abilities could be improved by P. rhodesiae GRC140 and exogenous IAA application.

Reducing the risk of the aquatic ecosystem’s contamination with organic substances such as pharmaceuticals is of great importance due to the toxicological effect of these substances on aquatic organisms. Therefore, the removal of pharmaceuticals and/or their metabolites frequently reported in industrial or municipal wastewaters require efficient processes that complement the conventional treatment systems; the constructed wetlands are an option. In this work, the removal efficiency of mixed diclofenac and naproxen was evaluated using a subsurface flow constructed wetland planted with cattail (Typha latifolia), operated during 100 days at a hydraulic residence time (HRT) of 3 days. Under these conditions, the diclofenac and naproxen removal efficiencies were 82.0% and 74.5%, respectively. The interaction between diclofenac and naproxen with cellulose, which is the major cell wall compound of higher plants, was computationally modeled at the PM6 semi-empirical level of theory and it was found that diclofenac and naproxen interact with cellulose via hydrogen bonds. Resumen. Reducir el riesgo de contaminación de los ecosistemas acuáticos con sustancias orgánicas como los fármacos es de gran importancia debido al efecto toxicológico de estas sustancias para los organismos acuáticos. Por ello, la remoción de los fármacos y/o sus metabolitos frecuentemente reportados en aguas residuales industriales o municipales requiere de procesos eficientes que complementen los sistemas convencionales de tratamiento; los humedales construidos son una opción. En este trabajo, se evaluó la eficiencia de remoción de diclofenaco y de naproxeno en mezcla utilizando un humedal construido de flujo subsuperficial con plantas de tule (Typha latifolia), operado durante 100 días con un tiempo de residencia hidráulica (TRH) de 3 días. En estas condiciones, las eficiencias de remoción de diclofenaco y de naproxeno fueron de 82.0 % y 74.5 % respectivamente. La interacción entre diclofenaco y naproxeno con celulosa, que es el componente mayoritario de la pared celular de las plantas superiores, se modeló computacionalmente al nivel de teoría semiempírico con el método PM6, y se encontró que diclofenaco y naproxeno interactúan con celulosa mediante puentes de hidrógeno.