Insight into the distribution of pharmaceuticals in soil-water-plant systems

Abstract

Pharmaceuticals in agricultural soils originating from irrigation with treated wastewater and landapplied biosolids can enter field crops. However, little is known about the role of pore water in plant uptake of pharmaceuticals from soil. In this study, the fate, uptake and distribution of fifteen commonly used pharmaceuticals in soil-water-radish systems were investigated to examine the relationship between the accumulation and their physicochemical processes in soils. The results indicate that the distribution of pharmaceuticals between soil and pore water, as well as their biodegradation, combined to govern the bioavailability of pharmaceuticals to plant uptake. Fourteen out of 15 pharmaceuticals could enter radish tissues in which the accumulation ranged from 2.1 to 14080 ng/g. Comparison of bioconcentration factors (BCFs) on the basis of pharmaceutical concentration in bulk soil vs. in pore water implies that pharmaceuticals present in soil pore water are the major bioavailable fractions to plant uptake. The pore water-based BCFs exhibited a positive linear relationship with log Dow for the pharmaceuticals with > 90% as neutral species in soil pore water, while such relationship was not observed between bulk soil-based BCFs and log Dow mainly due to sorption by soil. Other than hydrophobicity, the dissociation of ionizable pharmaceuticals in the soil pore water and (or) root cells may lead to the "ion-trap" effects and thus influence the uptake and translocation process. The large molecular size pharmaceuticals (e.g., tylosin) manifested a minimum uptake due plausibly to the limited permeability of cell membranes.

Improved prediction of the bioconcentration factors of organic contaminants from soils into plant/crop roots by related physicochemical parameters

“…For the soil-plant RCF (water) data from laboratory or field studies, only the data for samples with > 7 days (up to 93 days) of exposure were selected, with most data (~85%) having exposure times of 39–70 days. In either case, no RCF (water) data of ionic and ionizable chemicals were selected since their uptakes by plants may involve more than a partition process (Tanoue et al, 2012; Wu et al, 2013; Li et al, 2019). When adopting the soil-plant data from literature, only the studies with reported soil f om and accessible plant f lip values were selected.…”

How microbial community composition, sorption and simultaneous application of six pharmaceuticals affect their dissipation in soils

“…The environment can also be polluted by veterinary pharmaceuticals from animal urine or farm waste (e.g., Charuaud et al, 2019). Pharmaceuticals that contaminate soils may subsequently leach to groundwater (e.g., Burri et al, 2019;Godfrey et al, 2007;Fram and Belitz, 2011;Lesser et al, 2018;Li, 2014;Loos et al, 2010) or can be taken up by plants (e.g., Ahmed et al, 2015;Al-Farsi et al, 2017;Christou et al, 2019;Goldstein et al, 2014;Klement et al, 2020;Kodešová et al, 2019aKodešová et al, , 2019bLi et al, 2018Li et al, , 2019aLi et al, , 2019bMalchi et al, 2014;Montemurro et al, 2017;Mordechay et al, 2018;Shenker et al, 2011;Winker et al, 2010;Wu et al, 2013). Further propagation of pharmaceuticals in the environment depends on their sorption and dissipation in the vadose zone (e.g., Carter et al, 2019;Kümmerer, 2009aKümmerer, , 2009bZhi et al, 2019).…”

Detection, occurrence, and fate of emerging contaminants in agricultural environments (2020)

“…This work was expanded by Li, Sallach, Zhang, Boyd, and Li (2019) who evaluated the additional complexity of soil in the radish production system. This study showed that bioconcentration in lettuce plant material was positively correlated with soil–water partitioning ( D ow ) for neutral compounds.…”