Transport of Nano- and Microplastic through Unsaturated Porous Media from Sewage Sludge Application

Abstract

The Mar Menor is the largest lagoon along the Spanish Mediterranean coast. It suffers from eutrophication and algal blooms associated with intensive agricultural activities and urban pressure in the surrounding Campo de Cartagena plain. A balanced discharge of groundwater, carrier of algal nutrients such as nitrate, is essential to ensure the integrity of the coastal lagoon and the availability of groundwater resources inland.We here present a 3D hydrogeological model of the unconfined Quaternary aquifer that discharges into the lagoon. The model couples both surface water balance and groundwater dynamics and has been calibratedThis document is the accepted manuscript version of the following article: Keller,

A Nanoplastic Sampling and Enrichment Approach by Continuous Flow Centrifugation

“…Using metal-doped particles is a promising new approach. Even with a trace metal content embedded in the polymer of <0.5% w/w, the sensitivity of ICP-MS enables particle detection at lower concentrations in a variety of complex matrices (Keller et al, 2019;Mitrano et al, 2019;Schmiedgruber et al, 2019) after total microwave-assisted acid digestion (MWAD) of the bulk sample. While only a model, metal-doped particles can also be a valuable tool when it comes to the investigation of potential techniques for environmental NPP extraction and enrichment.…”

Development and application of tests for microplastic detection in soil

“…The observation correlates with what Zhang et al (2020c) described for plastic mulch where 96% of microplastics remained in the topsoil. Keller et al (2020) went further, however. These researchers observed that the mobile organic fraction of sludge co-transported nanoplastic particles (180nm) along the glass pearl column.…”

“…Laboratory studies that assess the mobility of microplastics moving from the topsoil to deeper soil layers support the field observations that suggest organic matter and microplastics move together through soil's pore space. Using marked microplastics, Keller et al (2020) tested how microplastic fibres from sewage sludge migrate through a column filled with 1mm glass pearls (polyester fibres of Ø = 30μm and 510 ±12μm) . The authors observed that more than 95% of the fibres remained attached to the sludge and stayed at the top of the column.…”

“…Ecotoxicological studies have evaluated mostly polystyrene and light density polyethylene (Cao et al, 2017;Jiang et al, 2020). Studies that address the transport of microplastic particles through the soil profile have focused only on laboratory conditions, including only a limited selection of polymers (polyethylene and polyester) and shapes (microbeads, fibres) (Keller et al, 2020;O'Connor et al, 2019;Yu et al, 2019). And what about bioplastics?…”

“…Is this definition appropriate for soils? Movement thorough the soil's pore space happens only for plastic particles less than 500μm (Keller et al, 2020). And earthworms guts malfunction or can become blocked when plastic particles as small as 1μm are present, so what happens with the particles are as large as 5mm (Jiang et al, 2020)?…”