As emerging alternatives of legacy perfluoroalkyl substances, perfluorophosphinates (PFPiAs) and perfluorophosphonates (PFPAs) are widely applied in industrial and agricultural fields and are supposed to be large partitioned to soil and highly persistent. It is of particular interest to understand their transfer from roots to shoots and transformation in plants, such as wheat. The results of hydroponic experiments indicated that C6/C6 PFPiA, C8/C8 PFPiA, perfluorooctanophosphonic acid (PFOPA), and perfluorohexaphosphonic acid (PFHxPA) were quickly adsorbed on the epidermis of wheat root (Triticum aestivum L.), which was driven by their hydrophobicity. A small fraction of the accumulated PFPiAs and PFPAs in the wheat root was subjected to absorption via an active process dependent on H+-ATPase. PFHxPA, which has the smallest molecular weight and medium hydrophilicity (log K ow < 4), displayed the strongest absorption efficiency via the water and anion channels and had the highest translocation potential from roots to shoots in wheat. C6/C6 and C8/C8 PFPiAs experienced phase I metabolism in wheat, although at a low rate, to form more persistent PFHxPA and PFOPA, respectively, as well as 1H-perfluorohexane (1H-PFHx) and 1H-perfluorooctane (1H-PFO), which were regulated by cytochrome P450 in wheat root. As a result, exposure to PFPiAs in roots ultimately caused the accumulation of more persistent PFPAs in the above-ground parts of plants, raising concerns on their potential risks on human health.

The effect of pH on inhibition and enhancement of luminol-H2O2-Co2+ chemiluminescence (CL) by 18 phenolic compounds and 20 amino acids was studied. It was found that most of the tested compounds showed an inhibiting effect at lower pH and an enhancing effect at higher pH. At a midrange pH, for some phenolic compounds with two ortho-position -OH, both an inhibiting and an enhancing peak were simultaneously observed. UV-visible spectra of the tested phenolic compounds at different pH values were studied. The mechanism for CL inhibition and enhancement was proposed. It is likely that the competition of the -OH or the -NH2 group and other reducing groups in the molecules with luminol for O2*- led to the CL inhibition. A reaction of -COO(-) and quinone or ketone formed by phenolic compounds at higher pH via deprotonation with O2*- also resulted in the CL enhancement.

A cross-sectional study of 25 sample sets (each set consisted of maternal serum and cord whole blood) from 50 pregnant women in zone A (n = 25 from exposed group) and zone B (n = 25 from reference group) was conducted to examine the association between thyroid hormone (TH) levels and PBDE, PCDD/F, and PCB exposures. Thyroid hormones TT3, TT4, and TSH levels were measured in maternal serum at 16 weeks of gestation. The concentrations of PBDEs, PCDD/Fs, and PCBs were determined by isotope dilution HRGC/HRMS in cord blood samples. Body burdens of the three contaminants in cord blood in zone A (median: summation sigma TEQ-PCDD/Fs 0.041, summation operator TEQ-PCBs 0.022 pg WHO-TEQ/g, summation operator PBDEs 23.4 pg/g whole weight, respectively) were significantly higher than those from the reference area (median: summation sigma TEQ-PCDD/Fs 0.014, summation sigma TEQ-PCBs 0.0041 pg WHO-TEQ/g, summation sigma PBDEs 16.15 pg/g, respectively) (p < 0.05). Levels of TT4 and TSH in serum in zone A were significantly lower than those in zone B (p < 0.05). A negative correlation was found between TT4 levels and body burdens of PCDD/Fs and PCBs. However, there was no significant association of concentration of PBDEs and levels of the three thyroid hormones. Our results suggest that electronic waste (e-waste) recycling contributes to high body burdens of PBDEs, PCDD/Fs, and PCBs and affects thyroid hormone homeostasis in humans. The potential health risk for neonates still needs further investigation.

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The biotransformation of organophosphate esters (OPEs) in white lupin (Lupinus albus) and wheat (Triticum aestivum L.) was investigated in hydroponic experiments with different phosphorus (P)-containing conditions. The hydrolysis rates of OPEs followed the order of triphenyl phosphate (TPHP) > tri-n-butyl phosphate (TnBP) > tris­(1,3-dichloro-2-propyl) phosphate (TDCPP). Hydrolysis of OPEs was accelerated at P-deficient conditions, and faster hydrolysis took place in white lupin than in wheat. Coincidingly, the production of acid phosphatase (ACP) in both plants was promoted, and much higher intracellular and extracellular ACPs were observed in white lupin under P-deficient conditions. In vitro experiments revealed that ACP was a key enzyme to hydrolyze OPEs. The hydrolysis rates of OPEs were significantly correlated with the Hirshfeld charges, calculated by density functional theory, of the oxygen atom in the single P–O bond. Using ultra-high-performance liquid chromatography coupled with Orbitrap Fusion mass spectrometer, 30 metabolites were successfully identified. Some of these metabolites, such as sulfate-conjugated products, hydration of cysteine-conjugated products of TPHP, and reductively dechlorinated metabolites of TDCPP, were observed for the first time in plants. It is noteworthy that OPEs may transform into many hydroxylated metabolites, and special attention should be paid to their potential environmental effects.