Evaluation of a QuEChERS-like extraction approach for the determination of PBDEs in mussels by immuno-assay-based screening methods

Spatial monitoring and health risk assessment of polybrominated diphenyl ethers in environmental matrices from an industrialized impacted canal in South Africa

This study investigates the pollution of Markman stormwater runoff, which is a tributary to Swartkops River Estuary. Solid-phase and ultrasonic extraction methods were utilized in the extraction of water and sediment samples, respectively. The pH of the sampling sites was above the EU guideline. The ranges of concentration of [Formula: see text]PBDE obtained in water and sediment samples for all the seasons were 58.47-1357 ng/L and 175-408 ng/g, respectively. Results also showed that BDE-66 was the dominant congener, specifically in the industrial zone, where its concentrations ranged from 2 to 407 ng/g in sediment. Consequently, the high concentration of BDE- 66 in the sediment of stormwater calls for concern. Penta-BDE suggests potential moderate eco-toxicological risk, as evident in the calculated risk assessment. The result showed possible photodegradation along the contaminant's travel time, as only 7% of the PBDE was detected at the point of entry into the Swartkops River Estuary. Markman stormwater may be contributing heavily to the pollution load of Swartkops River, as evident in the alarming concentrations of PBDEs obtained. The industries at this zone should eliminate the contaminants before discharging their effluents into the canal.

Bioaccumulation of different congeners of Poly-Brominated Diphenyl Ethers (PBDEs) in muscle tissue of males and females of Clupea harengus from the North Sea

In the last decades, high concentrations of flame retardants (PBDE) in marine organisms have caused increasing concern among scientists with regards to their biomagnification potential and to human health. Poly-Brominated Diphenyl Ethers have been widely used in the past as flame retardants in various industrial sectors, and their presence in the biota has been associated with different toxicological effects. In this study, concentrations of 9 congeners of PBDE (183, 85, 153, 154, 99, 100, 47, 66 and 28) and morphometric parameters (Total Length, TL; Fork Length, FL in cm and weight) have been measured in muscle of males and females of Atlantic herring (Clupea harengus). Results showed no statistical differences between the concentrations of most of the congeners analysed between the two sexes, except for PBDE 153 (Mean ± standard error in males = 0.034 ± 0.005 μg/kg and in females = 0.086 ± 0.040 μg/kg; p = 0.003). This research contributes to better comprehend the ecotoxicological properties of these molecules and their implications for human consumption.

Trends and Perspectives in Immunosensors for Determination of Currently-Used Pesticides: The Case of Glyphosate, Organophosphates, and Neonicotinoids

Pesticides, due to their intensive use and their peculiar chemical features, can persist in the environment and enter the trophic chain, thus representing an environmental risk for the ecosystems and human health. Although there are several robust and reliable standard analytical techniques for their monitoring, the high frequency of contamination caused by pesticides requires methods for massive monitoring campaigns that are capable of rapidly detecting these compounds in many samples of different origin. Immunosensors represent a potential tool for simple, rapid, and sensitive monitoring of pesticides. Antibodies coupled to electrochemical or optical transducers have resulted in effective detection devices. In this review, the new trends in immunosensor development and the application of immunosensors for the detection of pesticides of environmental concern-such as glyphosate, organophosphates, and neonicotinoids-are described.

Glyphosate Determination by Coupling an Immuno-Magnetic Assay with Electrochemical Sensors

Glyphosate (N-(phosphonomethyl)glycine) is the most frequently used broad-spectrum herbicide worldwide. Its mechanism of action is based on the inhibition of an enzyme that is essential to plant growth. Its intensive use has caused global contamination to occur, which has not only affected the ecosystems, but even food and other objects of common use. Thus, there is a pronounced need for developing analytical methods for glyphosate determination in different matrices. Here, an electrochemical competitive immunoassay, based on the use of antibody-modified magnetic particles, has been developed. Tetramethylbenzidine (TMB) has been used as an enzymatic substrate. The extent of the affinity reaction has been achieved by monitoring the current value, due to the reduction of the enzymatic product. A disposable screen-printed electrochemical cell has been used. The calibration curve has been recorded in the 0⁻10,000 ng/L concentration range, with a detection limit of 5 ng/L and quantification limit of 30 ng/L. The electrochemical immunoassay has also been applied to the analysis of spiked beer samples.