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Substituted polycyclic aromatic hydrocarbons (sub-PAHs) are receiving increased attention due to their high toxicity and ubiquitous presence. However, the accumulation behaviors of sub-PAHs in crop roots remain unclear. In this study, the accumulation mechanism of sub-PAHs in crop roots was systematically disclosed by hydroponic experiments from the perspectives of utilization, uptake, and elimination. The obtained results showed an interesting phenomenon that despite not having the strongest hydrophobicity among the five sub-PAHs, nitro-PAHs (including 9-nitroanthracene and 1-nitropyrene) displayed the strongest accumulation potential in the roots of legume plants, including mung bean and soybean. The nitrogen-deficient experiments, inhibitor experiments, and transcriptomics analysis reveal that nitro-PAHs could be utilized by legumes as a nitrogen source, thus being significantly absorbed by active transport, which relies on amino acid transporters driven by H + -ATPase. Molecular docking simulation further demonstrates that the nitro group is a significant determinant of interaction with an amino acid transporter. Moreover, the depuration experiments indicate that the nitro-PAHs may enter the root cells, further slowing their elimination rates and enhancing the accumulation potential in legume roots. Our results shed light on a previously unappreciated mechanism for root accumulation of sub-PAHs, which may affect their biogeochemical processes in soils.

In this study, the gas-phase retention volume behavior of four highly volatile organophosphate esters (OPEs) on polyurethane foam (PUF) was studied using a frontal chromatogram. The breakthrough volumes (V B ) of trimethyl phosphate (TMP), triethyl phosphate (TEP), tripropyl phosphate (TPrP), and tri-n-butyl phosphate (TnBP) were 0.33, 0.59, 10.5, and 32.4 m 3 , respectively. A significant negative correlation was found between the logarithm value of V B and the subcooled liquid vapor pressure (P L ) with an r 2 of 0.905, indicating that the vapor penetration depends on both the volatility and total air volume. The enthalpy of desorption and vaporization (ΔH S -ΔH V ) showed a significant difference between the tested OPEs and polycyclic aromatic hydrocarbons (PAHs), revealing that the strength of the sorption interaction of the tested OPEs vapor on PUF should be different from that of PAHs. The PUF-air partition coefficients (K PUF-air ) of the tested OPEs ranged from 4.3 to 8.1, which were lower than those of three-to four-ring PAHs (7.02-10.2) and organochlorines (8.01-9.72), revealing that the partition of highly volatile OPEs on PUF is lower than that of low-volatile compounds. The PUF/XAD cartridge improved the absorption efficiency of the tested OPEs; however, its sorptive capacity was still limited., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

While pollution of the environment by polycyclic aromatic hydrocarbons has been rather well studied, the fate of substituted polycyclic aromatic hydrocarbons in ecosystems is less understood, notably in soil–plant systems. Here we hypothesized that substituted polycyclic aromatic hydrocarbons could enter wheat and induce phytotoxicity. We studied the accumulation, root-shoot translocation and phytotoxicity of α-tetralone, 1-nitronaphthalene, 1-nitropyrene, and 7,12-dimethylbenz[a]anthracene in wheat using hydroponic experiments. We deciphered the accumulation and translocation mechanisms by inhibition with sodium vanadate, glycerol and silver nitrate. Results show that pollutant concentrations increased rapidly in roots, reaching maximum of 38.3 μg/g for α-tetralone, 268.7 μg/g for 1-nitronaphthalene, 3566.1 μg/g for 1-nitropyrene, and 3632.7 μg/g for 7,12-dimethylbenz[a]anthracene. In contrast, the root-shoot translocation factors of α-tetralone, 1-nitronaphthalene, 1-nitropyrene and 7,12-dimethylbenz[a]anthracene were 2.4, 1.6, 0.1, and 0.1, respectively, thus decreasing significantly with increasing compound hydrophobicity. This could be explained by preferential adsorption for hydrophobic compounds, whereas less hydrophobic compounds could be partly translocated in a soluble form through plant water channels. The accumulated substituted polycyclic aromatic hydrocarbons in wheat induced the decrease of the total chlorophyll contents by 19.0–30.1%, yet did not cause lipid peroxidation damage. Overall, our findings indicates the bioaccumulation potential and toxicity of substituted polycyclic aromatic hydrocarbons in terrestrial plants. [ABSTRACT FROM AUTHOR]

[Display omitted] • MATF and MRP enriched substantial heavy metals and PAHs from the environment. • MATF and MRP from actual artificial turf had significantly higher cytotoxicity. • EPFRs and ROS had limited contributions to the cytotoxicity of aged MATF and MRP. • Heavy metals and PAHs played important roles in the toxicity of MATF and MRP. Numerous micro-sized artificial turf fragments (MATF) and rubber particles (MRP) are generated and accumulated during the use of the artificial playing field. However, attention has rarely been paid to the potential toxic effects of MATF and MRP on sportsmen. In this study, the active components and chemical composition of aged MATF and MRP derived from laboratory photoaging and actual field sampling were detected, and their effects on cytotoxicity were examined correspondingly. Laboratory photoaging significantly increased environmental persistent free radicals (EPFRs), reactive oxygen species (ROS) abundances and oxidative potential (OP) levels on MATF and MRP, but they have limited cytotoxicity. Unfortunately, in the actual field, aged MATF and MRP with higher heavy metals and polycyclic aromatic hydrocarbons (PAHs) contents exhibited markedly higher cytotoxicity with the survival rate of cells of 78 % and 26 % (p < 0.05), although they had lower EPFRs and ROS yields. Correlation analysis revealed that the cell viability was closely linked to heavy metals of MATF (p < 0.05), and to organic hydroperoxide (OHP), PAHs and heavy metals of MRP (p < 0.05). By systematically considering the above results, heavy metals and PAHs enriched on MATF and MRP from the surrounding environment played the important role in the cytotoxicity, which was different from conventional perspectives. Our findings demonstrate that MATF and MRP associated with an artificial turf field contain potent mixtures of pollutants and can, therefore, be relevant yet underestimated factors contributing to the health risks. [ABSTRACT FROM AUTHOR]