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Tire-derived particles and polyethylene (PE) debris co-exist in estuaries and potentially deteriorate water quality. Chemicals can be emitted from tire-derived particles and resorb to PE debris. However, there was lack of information about the interaction (e.g., sorption and desorption) between tire-derived chemicals and PE debris. By combining batch sorption and desorption experiments along with in situ field deployment of PE sheets, we examined the utility of benzothiazoles (BTZs) sorbed in PE as suitable markers of tire-derived inputs. The sorptive characteristics and PE-water partition coefficients (often designated as K pew) of selected tire-derived marker candidates, i.e., polycyclic aromatic hydrocarbons (PAHs), benzothiophenes (BTPs) and BTZs, were measured. Moderately polar BTPs and BTZs (except for 2-(4-morpholinyl) benzothiazole) reached equilibrium within 2–8 days, compared to 20 days for nonpolar PAHs. The measure K pew values and octanol-water partition coefficients of PAHs and BTZs were linearly correlated with each other (r 2 > 0.80; p < 0.05). The desorption potentiality of PAHs and BTZs from tire particles is consistent with the hydrophilic properties of the target chemicals, while desorption ratios of BTZs and PAHs are 25–87% and <20%, respectively. Samplers with PE sheets as the sorbent phase were deployed in Hailing Bay, an urbanized estuary in South China, to measure concentrations of PAHs, BTPs and BTZs. Benzothiazoles sorbed in PE samples were associated with the massive utilization of automobile tires, while PAHs were linked to the boat maintenance facilities and BTPs were not detected in any tire particle and field PE samples. Therefore sorbed BTZs in PE can potentially serve as chemical markers of tire-derived inputs to estuaries. [Display omitted] • Benzothiazoles reach equilibrium between polyethylene and water within 2–8 days. • Benzothiazoles are weakly attracted to tire rubber matrices. • Benzothiazoles sorbed in polyethylene are related to utilization of tires. • Sorbed benzothiazoles are suitable markers of tire-derived leachate inputs. [ABSTRACT FROM AUTHOR]

The partition coefficient (K pew) of an analyte between low-density polyethylene (LDPE) film and water is a critical parameter for measuring freely dissolved concentrations of the analyte with PE passive sampling devices. Measuring log K pew for super hydrophobic organic chemicals (HOCs) have been proven extremely difficult. The present study developed a large volume model for measuring log K pew of super HOCs, i.e., novel halogenated flame retardants (NHFRs). Results showed that the measured log K pew values of selected PAHs and PCBs obtained by the large volume model were in line with those from the co-solvent model and the literature data within less 0.3 log units of difference, while those of NHFRs (6.27–7.34) except for hexachlorocyclopentadienyldibromocyclooctane (HCDBCO) and Decabromodiphenyl ethane (DBDPE) were significantly lower than those (6.51–8.89) from the co-solvent model. A curvilinear relationship was observed between log K pew and log K ow of all target compounds, with the turning point at log K ow = ∼8.0 in the large volume model, but that was not found for the co-solvent model. These can be attributed to the large molecular volumes (> 450 Å3) for NHFRs, which require high Gibbs free energy to penetrate into the inside structures of LDPE in the large volume model. However, the solvent swelling effects in the co-solvent model needs to be investigated. Therefore, the large volume model is robust to determine the K pew values of super HOCs for facilitating the application of aquatic passive sampling techniques. • The large volume model is feasible to measure the K pew values of super HOCs. • The K pew values of HOCs from the co-solvent model were greater than other models. • The K pew values of NHFRs decreased with increasing molecular volumes. [ABSTRACT FROM AUTHOR]

Marine antibiofouling using low-amplitude electric pulses (EP) is an energy-efficient and eco-friendly approach, but potential mechanisms for preventing biofouling remain unclear. In the present study, the 3D adhesion dynamics of a model microorganism─ Pseudomonas aeruginosa (PAO1)─under low-amplitude cathodic EP were examined as a function of applying voltage and its duration ( t d ). The results demonstrated that adhered bacteria escaped from the electrode surface even when EP was removed. The escaped bacteria ratio, induction period of escape, and duration of the detachment were influenced profoundly by EP amplitude but slightly by t d when t d ≥ 5 min. The acceleration of escaped PAO1 from the surface indicated that their flagellar motor was powered by EP. Particularly, EP enabled swimming bacteria to have adaptive motions that were sustainable and regulated by the gene rsmA . As a result, they had less accumulation near the surface. The propulsion of adhered bacteria and adaptive escape of swimming bacteria were enhanced in response to low-amplitude EP. Hence, low-amplitude and short-duration EP is promising for sustainable antibiofouling applications.

Dermal absorption of gaseous chemicals is an important contributor to increased health risk and has yet to be adequately addressed due to the lack of available sampling techniques. In the present study, a novel personal passive sampler consisting of a housing (embracing a polydimethylsiloxane (PDMS) disk as the sorbent phase, a membrane filter, and a stainless-steel mesh) and a watchband (traditional wristband) was constructed and used to characterize gaseous phthalates (PAEs) near the air-skin interface. In a real-life setting, the utility of the passive sampler was validated by comparing the composition profiles of PAEs in the PDMS disks and in active samples and watchbands. The compositions of PAEs were consistent in disks and gaseous constituents from ambient air, with low-molecular-weight (<306 g mol -1 ) PAEs accounting for 87-100% and approximately 100%, respectively. Appreciable amounts of diisononyl phthalate, diisodecyl phthalate, dinonyl phthalate, and skin lipid (e.g., squalene) were detected in watchbands but not in disks. Apparently, the passive sampler can prevent particles and skin-related chemicals from adhering to the disk and collect gaseous PAEs only. The vast majority of PAEs in watchbands was associated with nongaseous constituents. The present study demonstrated that the sampling strategy is a key factor in exposure assessment.