Effect of irrigation water type and other environmental parameters on CeO2 nanopesticide-clay colloid interactions

Environmental Biolog

Copper, zinc, mercury and arsenic content in Micropogonias furnieri and Mugil platanus of the Montevideo coastal zone, Río de la Plata

Abstract Metals (Cu, Zn, Hg) and metalloid (As) concentrations were measured in Micropogonias furnieri and Mugil platanus caught in three areas along the Montevideo coastal zone during winter 2010, spring 2010 and 2011. Compared to previous studies conducted in the zone, both species showed higher (for Cu), similar (for Zn) or lower (for Hg) concentrations. The highest Hg values were found in the M. furnieri of Montevideo bay. There was no spatial variation in Cu, Zn, and As concentrations in muscle, likely due to the high mobility of both species. However, the Cu content in the liver of M. furnieri was higher in fish from the West zone. Cu, Zn and As found in the liver of M. platanus were much higher than in that of M. furnieri. A functional relationship between muscle levels of Zn and Hg and fish length of M. furnieri indicates bioaccumulation of these metals. According to the results, M. furnieri may be used as a temporal bioindicator for Hg, but not as a spatial bioindicator. Mercury levels were below the maximum safety level based on international standard values for human consumption

Accurate quantification of TiO2 nanoparticles in commercial sunscreens using standard materials and orthogonal particle sizing methods for verification

FWN – Publicaties zonder aanstelling Universiteit Leide

Method for Extraction and Quantification of Metal-Based Nanoparticles in Biological Media: Number-Based Biodistribution and Bioconcentration

A multistep sample preparation method was developed to separate metal-based engineered nanoparticles (ENPs) from biological samples. The method was developed using spiked zebrafish tissues and standard titanium dioxide (TiO2) and cerium dioxide (CeO2) ENPs. Single-particle inductively coupled plasma mass spectrometry was used to quantify the separated particles in terms of number concentration. This method demonstrated mass recoveries of more than 90% and did not strikingly alter the median particles size. High number recoveries were calculated for CeO2 ENPs (>84%). Particle number recoveries were poor for TiO2 ENPs (48Ca with the measured isotope 48Ti. The method was verified using zebrafish exposed to CeO2 ENPs to test its applicability for nanotoxicokinetic investigations. Total mass of Ce and particle number concentration of CeO2 ENPs were measured in different tissues. Notably, the mass-based biodistribution of Ce in the tissues did not follow the number-based biodistribution of CeO2. Moreover, the calculated mass-based bioconcentration factors showed a different pattern in comparison to the number-based bioconcentration factors. Our findings suggest that considering mass as the sole dose-metric may not provide sufficient information to investigate toxicity and toxicokinetics of ENPs.Environmental Biolog