Identification and quantification of plastic additives using pyrolysis-GC/MS: A review.

Analysis of organic plastic additives (OPAs) associated to plastic polymers is growing. The current review outlines the characteristics and the development of (multi-step) pyrolysis coupled with a gas chromatography mass spectrometer (Py-GC/MS) for the identification and semi-quantification of OPAs. Compared to traditional methods, Py-GC/MS offers advantages like suppressing extensive steps of preparation, limiting contamination due to solvents and the possibility to analyse minute particles. Its key advantage is the successive analysis of OPAs and the polymeric matrix of the same sample. Based on the studied articles, numerous methods have been described allowing identification and, in some case, semi-quantification of OPAs. There is nevertheless no gold standard method, especially given the huge diversity of OPAs and the risks of interferences with polymers or other additives, but, among other parameters, a consensus temperature seems to arise from studies. More broadly, this review also explores many aspects on the sample preparation like weight and size of particles and calibration strategies. After studying the various works, some development prospects emerge and it appears that methodological developments should focus on better characterizing the limits of the methods in order to consider which OPAs can be quantified and in which polymers this is feasible.

Elimination of organochlorine pesticides from water by a new activated carbon prepared from Phoenix dactylifera date stones.

This work focused on the characterization of activated carbon (AC) prepared by pyrolysis-chemical activation with phosphoric acid (60%) from date stones derived from three categories of date palm Phoenix dactylifera (Ajwa, Anbari, Khudri), and on its feasibility of elimination of organochlorine pesticides (OCPs) in water samples. The obtained results showed that the three-produced AC date stone had developed a porous structure, large specific surface area, and acidic property. Due to the high SBET (> 1200 m2/g), Ajwa stones activated coal was considered as the best AC that can be used for the adsorption of environmental contaminants. The effects of several parameters such as the Ajwa AC dose, the time of contact, the initial concentration of pesticides, and the pH were evaluated. The results showed that the adsorption balance of organochlorine pesticides on this AC was reached after a contact time of 60 min at an optimal pHzpc equal to 2. In addition, 0.4 g of AC was the best quantity found to retain the largest quantity of pesticides while considering the economic part.

Distribution of phthalates, pesticides and drug residues in the dissolved, particulate and sedimentary phases from transboundary rivers (France-Belgium).

Various drug residues, pesticides and phthalates are ubiquitous in the environment. Their presence in the environment has attracted considerable attention due to their potential impacts on ecosystem functioning and on public health. In this work, 14 drug residues, 24 pesticides and 6 phthalates have been quantified in three matrices (in the dissolved phase, associated to suspended solid matter (SSM), and in sediment) collected from fifteen watercourses and rivers located in a highly industrialized zone at the cross-border area of Northern France and Belgium. The extractions have been carried out using accelerated solvent extraction (ASE) for solid matrices (SSM and sediment) and using solid phase extraction (SPE) for liquid matrix. The final extract was analyzed using GC-MS technique. Among the three classes of compounds, phthalates have been found at highest level compared to pesticides and drug residues. The Σ6PAE concentrations were ranging from 17.2±2.58 to 179.1±26.9µgL(-1) in dissolved phase, from 2.9±0.4 to 21.1±3.2µgL(-1) in SSM and from 1.1±0.2 to 11.9±1.8µgg(-1)dw in sediment. The Σ14drug residue concentrations were lower than 1.3µgL(-1) in the dissolved phases, lower than 30ngL(-1) associated to SSM and from nondetectable levels to 60.7±9.1ngg(-1)dw in sediment. For pesticides, all compounds were below the LOQ values in dissolved phase and in sediment, and only EPTC could be quantified in SSM.