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Long-term atmospheric quality monitoring of PM2.5 and PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) was performed in Wuxi from 2016 to 2021. A total of 504 atmospheric PM2.5 samples were collected, and PM2.5-bound 16 PAHs were detected. The PM2.5 and ∑PAHs level decreased annually from 2016–2021, from 64.3 to 34.0 μg/m3 and 5.27 to 4.22 ng/m3, respectively. The benzo[a]pyrene (BaP) of 42% of the monitoring days in 2017 exceeded the recommended health-based standard of the European Union (EU) at 1ng/m3. Five- and six-ring PAHs, including benz[a]anthracene (Baa), benzo[k] fluoranthene (Bkf), BaP, and benzo[g,h,i]perylene (Bghi), were the dominant components, indicating a prominent petroleum, biomass, and coal combustion contribution by molecular diagnostic ratios and positive matrix factorization analysis. Statistically significant temporal and spatial distribution differences of PM2.5, and ∑PAHs were also found. The toxicity equivalent concentration (TEQ) was 0.70 for total PAHs and the TEQ of BaP (0.178) was the highest, followed by Bkf (0.090), dibenz[a,h]anthracene (Dah) (0.048), and indeno[1,2,3-cd]pyrene (Ind) (0.034). The medians of the incremental lifetime cancer risk (ILCR) for long-term exposure to PAHs were 2.74E-8, 1.98E-8, and 1.71E-7 for children, teenagers, and adults, respectively, indicating that the carcinogenic risk of PAHs pollution in air was acceptable to local residents in this area. Sensitivity analysis showed that BaP, Bkf, and Dah significantly contributed to carcinogenic toxicity. This research supplies comprehensive statistics on the local air persistent organic pollutants profile, helps to identify the principle pollution source and compounds, and contributes to the prevention of regional air pollution.

Water elements pollution has attracted public attention globally. Wuxi is located in East China, and its water source, Taihu Lake, has been severely polluted since 2007. Studies of elemental pollution profiles have yet to be conducted in this area. In this study, 56 water samples were collected in 2018, and 33 elements were determined using inductively coupled plasma-mass spectrometry (ICP-MS). The results showed that the levels of 33 elements ranged from 1.35 × 10

The aim of this study was to examine the qualitative and quantitative analysis of Pb2+ adsorption mechanisms performed with biochars derived from rice straw (RSBs), rice husk (RHBs) and saw dust (SDBs) at several pyrolysis temperatures (400-600 °C) in a fluidized bed system. Adsorption isotherms, kinetics, and desorption analysis were determined, and biochars were analyzed by X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope with Energy Dispersive Spectrometer (SEM-EDS) and Boehm titration method. The effect of minerals on Pb2+ adsorption, including precipitation and cation exchange, revealed increasing contribution of precipitation from a range of 4.13%-38.83% to a range of 34.08%-79.94% and decreasing effect of cation exchange from a range of 50.17%-69.75% to a range of 9.57%-43.47% with increasing pyrolysis temperature. However, it remained the dominant adsorption mechanism of all biochars (accounted for 69.49-89.52%). Especially, RSBs with quite high maximum adsorption capacity (qm) values (116-127.57 mgg-1) were mainly due to precipitation mechanism of Pb2+ adsorption, which exhibited better adsorption capacities than RHBs (25.15-30.40 mgg-1) and SDBs (21.81-24.05 mgg-1). Only with the fluidized bed shown in this study, 2.00t RSBs could be produced and the corresponding Pb2+ adsorption may reach 255.50kg per year depending on its maximum adsorption capacity under 500 °C pyrolysis temperature. The results suggest that RSBs produced in a fluidized bed reactor is a promising, cost-effective, engineered biochar for application of Pb2+ remediation in aqueous solutions.

Quantum dots (QDs) are semiconductor fluorescent nanoparticles, which can be used for food safety or environmental monitoring with high sensitivity. This work demonstrates the feasibility of detecting clenuterol residue in pig urine using CdSe/CdS quantum dots as fluorescent labels based magnetic core/shell Fe3O4/Au nanoparticles (MCFN) as solid carriers. The detection of clenbuterol is carried out by a fluoroimmunoassay-based biosensor using competitive binding between conjugated clenbuterol antigen-CdSe/CdS QDs and free clenbuterol with immobilized clenbuterol antibodies on MCFN. This assay method allows for clenbuterol determination in a linear working range of 0.5-20000 pg mL(-1). It would provide a simple, rapid, and ultra-sensitive detection method for clenbuterol or other biomolecular analysis.