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Despite the increase in production, usage, and discharge of organophosphate flame retardants (OPFRs), little information is available about their bioaccumulation and trophic transfer in the marine food web. In this study, seawater, sediment, and marine species (10 fish and 9 invertebrate species) collected from Laizhou Bay, North China, were analyzed to investigate the levels, bioaccumulation, and biomagnification of OPFRs in a marine food web. Of 20 OPFRs screened for, 17 were quantifiable in seawater, sediment, and organisms. The ∑OPFRs concentrations ranged from 0.2 to 28.4 ng/L in seawater, 0.1−96.9 ng/g dry weight in sediment, and 21.1−3510 ng/g lipid weight in organisms. Benthic fish accumulated more OPFRs than pelagic fish and invertebrates. A linear and significant increase of bioaccumulation factors with increasing lipophilicity of OPFRs was observed (R 2 = 0.63, p < 0.05), and the biota-sediment accumulation factors increased with hydrophobicity up to log K OW = 4.59 and then decreased with increase in log K OW . Trophic magnification factors of OPFRs ranged from 1.06 to 2.52, indicating biomagnification potential of OPFRs in a marine food web. This study provides important insight into the biomagnification potential of OPFRs and suggests further investigation on this group of chemicals.

Little information is available about the bioaccumulation and biomagnification of antibiotics in marine food webs. Here we investigate the levels and trophic transfer of 9 sulfonamide (SA), 5 fluoroquinolone (FQ), and 4 macrolide (ML) antibiotics, as well as trimethoprim in nine invertebrate and ten fish species collected from a marine food web in Laizhou Bay, North China in 2014 and 2015. All the antibiotics were detected in the marine organisms, with SAs and FQs being the most abundant antibiotics. Benthic fish accumulated more SAs than invertebrates and pelagic fish, while invertebrates exhibited higher FQ levels than fish. Generally, SAs and trimethoprim biomagnified in the food web, while the FQs and MLs were biodiluted. Trophic magnification factors (TMF) were 1.2 – 3.9 for SAs and trimethoprim, 0.3 – 1.0 for FQs and MLs. Limited biotransformation and relatively high assimilation efficiencies are the likely reasons for the biomagnification of SAs. The pH dependent distribution coefficients (logD) but not the lipophilicity (logKOW) of SAs and FQs had a significant correlation (r = 0.73; p < 0.05) with their TMFs. Although the calculated estimated daily intakes (EDI) for antibiotics suggest that consumption of seafood from Laizhou Bay is not associated with significant human health risks, this study provides important insights into the guidance of risk management of antibiotics.

A pressurized liquid extraction-based method for the simultaneous extraction and in situ clean-up of polychlorinated biphenyls (PCBs), hydroxylated (OH)-PCBs and methylsulfonyl (MeSO2)-PCBs from small (< 0.5 gram) tissue samples was developed and validated. Extraction of a laboratory reference material with hexane:dichloromethane:methanol (48:43:9, v/v) and Florisil as fat retainer allowed an efficient recovery of PCBs (78–112%; RSD: 13–37%), OH-PCBs (46±2%; RSD: 4%) and MeSO2-PCBs (89±21%; RSD: 24%). Comparable results were obtained with an established analysis method for PCBs, OH-PCBs and MeSO2-PCBs.

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The objectives of this paper are to study the crystallization behavior and fracture characteristics of spherical alumina (Al2O3) nanoparticle‐filled polypropylene (PP) composites. Nanocomposites containing 1.5–5.0 wt % of the Al2O3 nanoparticles (pretreated with silane coupling agent) were prepared for this investigation. Wide angle X‐ray diffraction (WAXD) results show that a small amount of β‐crystal of PP forms after adding the Al2O3 nanoparticles. According to differential scanning calorimetric (DSC) and optical microscopy (OM) measurements, the Al2O3 nanoparticles make PP spherulite size reduced and crystallization temperature of PP enhanced, by acting as effective nucleating agents. However, there are no obvious differences in the crystallinity for the virgin PP and the Al2O3/PP nanocomposites. Tensile test shows that both the Young's modulus and the yield strength of the Al2O3/PP nanocomposites increase with the particle content increasing, suggesting that the interfacial interaction between the nanoparticles and PP matrix is relatively strong. Under quasi‐static loading rate, the fracture toughness (KIC) of the Al2O3/PP nanocomposites was found to be insensitive to nanoparticle content. Under impact loading rate, the Izod impact strength and the impact fracture toughness (Gc) indicate that the impact fracture toughness increases initially with the addition of 1.5 wt % of the Al2O3 nanofillers into the PP matrix. However, with the further addition of up to 3.0 and 5.0 wt % nanoparticles, both the Izod impact strength and impact Gc change very little. By observing the single‐edge‐double‐notch (SEDN) specimens with optical microscopy after four point bending (4PB) tests, it was found that numerous crazes and microcracks form around the subcritical crack tip, indicating that crazing and microcracking are the dominant fracture mechanisms. Scanning electron microscopy (SEM) observation confirms this result. In addition, when the strain rate of 4PB tests was increased, some wave‐like branches were formed along the fractured edge for the Al2O3/PP nanocomposites. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3652–3664, 2005