Detection and characterization of TiO$_2$ nanomaterials in sludge from wastewater treatment plants of Chihuahua State, Mexico

Reyes-Herrera, Juan (author), Acosta-Slane, Damaris (author), Castillo Michel, Hiram (author), Pradas del Real, Ana E. (author), Vogel-Mikuš, Katarina (author), Benetti, Federico (author), Roman, Marco (author), Villanova, Julie (author), Valles-Aragón, M. Cecilia (author)

TiO$_2$ nanoparticles (TiO$_2$-NPs) have a wide range of industrial applications (paintings, sunscreens, food and cosmetics) and is one of the most intensively used nanomaterials worldwide. Leaching from commercial products TiO$_2$-NPs are predicted to significantly accumulate in wastewater sludges, which are then often used as soil amendment. In this work, sludge samples from four wastewater treatment plants of the Chihuahua State in Mexico were obtained during spring and summer (2017). A comprehensive characterization study was performed by X-ray based (laboratory and synchrotron) techniques and electron microscopy. Ti was detected in all sludge samples (1810–2760 mg/kg) mainly as TiO$_2$ particles ranging from 40 nm up to hundreds of nm. MicroXANES data was analyzed by principal component analysis and linear combination fitting enabling the identification of three predominant Ti species: anatase, rutile and ilmenite. Micro-XANES from the smaller Ti particles was predominantly anatase (68% + 32% rutile), suggesting these TiO$_2$-NPs originate from paintings and cosmetics. TEM imaging confirmed the presence of nanoscale Ti with smooth surface morphologies resembling engineered TiO$_2$-NPs. The size and crystalline phase of TiO$_2$-NPs in the sludge from this region suggest increased reactivity and potential toxicity to agro-systems. Further studies should be dedicated to evaluating this.

• Language: English
• Keywords: nanoparticles, sewage sludge, X-ray microspectroscopy, synchrotron
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2022
• Number of pages: 21 str.
• Numbering: Vol. 12, iss. 5, art. 744
• PID: 20.500.12556/RUL-137272
• UDC: 549.514.6
• ISSN on article: 2079-4991
• DOI: 10.3390/nano12050744
• COBISS.SI-ID: 98738179
• Publication date in RUL: 09.06.2022

Record is a part of a journal

• Title: Nanomaterials
• Shortened title: Nanomaterials
• Publisher: MDPI AG
• ISSN: 2079-4991
• COBISS.SI-ID: 523286297

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 01.03.2022

Projects

• Funder: Other - Other funder or multiple funders
• Funding programme: Mexico, National Council for Science and Technology (CONACYT)

• Funder: ARRS - Slovenian Research Agency
• Project number: P1-0212
• Name: Biologija rastlin