Determination of organochlorine pesticides adsorbed on plastic pellets
2015, objavljeni povzetek znanstvenega prispevka na konferenci
Opis: In the past years, several studies have revealed the presence of organic contaminants at
concentrations from sub ng g–1 to mg g–1 on/in plastic pellets found in coastal environment
worldwide [1,2,3]. Plastic pellets are actually industrial raw material, typically in the shape of
small granules with a diameter of a few mm. They are categorized as microplastics (< 5 mm).
They can be unintentionally lost in the environment during manufacturing and transport. They
can subsequently reach the marine and coastal compartments. Due to their environmental
persistence, they are widely distributed in the oceans and on beaches . Organic pollutants
associated to pellets are either additives (e.g. PBDEs) that are incorporated into plastics during
production processes or hydrophobic chemicals (e.g. PCBs, organochlorine pesticides) which
adsorb from the surrounding environment (e.g. seawater). Among these chemicals, some are
recognized as POPs (Persistent Organic Pollutants) because of their persistence,
bioaccumulation and potential adverse environmental and health effects. Thus, in order to
better assess the impact of plastic pellets in coastal environment, it is necessary to determine
the level of associated organic pollutants.
The present study was carried out in the frame of DeFishGear project, which focuses on marine
litter and microplastics issues in Adriatic region. This investigation aimed at developing an
experimental protocol allowing the quantification of 11 organochlorine pesticides. Plastic
pellets, sampled on beaches located in the Adriatic region, were first sorted by colour. Pesticides
were extracted from the plastic matrix (c.a. 0.5 g) in a pressurized fluid extractor (50°C, 100 bar).
Prior to evaporation, the extract was cleaned on Florisil sorbent through solid-phase extraction
(SPE). The concentrated extracts were quantified on gas chromatography equipped with a micro
electron capture detector (GC-μECD). Preliminary results revealed the presence of DDT
Najdeno v: ključnih besedah
Ključne besede: organochlorine pesticides, microplastics, pellets, Adriatic region
Objavljeno: 15.02.2016; Ogledov: 3366; Prenosov: 0
Polno besedilo (3,92 MB)
Analysis of polychlorinated biphenyls adsorbed on plastic pellets: Comparison of extraction techniquesPetra Makorič
, 2017, magistrsko delo
Opis: Plastic resin pellets are one of the main components of plastic fragments in the marine environment. They are small granules, generally cylinder or disk-shaped, with a diameter of a few millimetres used as industrial raw material for the production of plastic manufactured items. Resin pellets can be unintentionally released to the environment during manufacturing and transport, and can reach the ocean through processes such as surface run-off. Because of their environmental persistence, they are widely distributed in the oceans and on the beaches, all over the globe. Plastic pellets are also a sink of toxic compounds such as polychlorinated biphenyls (PCBs) that are present in the environment.
During this thesis, we designed a protocol for extracting and analysing PCBs from marine plastic resin pellets. Although pressurized fluid extraction (PFE) is not commonly used in the field of microplastics, it is a reliable and efficient technique applied in other research areas. Thus, this method was tested in this work. PCBs were extracted from plastic pellets with PFE at 65 ºC and under 100 bar with hexane. Then, the extracts were concentrated to 1 mL, cleaned up on Florisil cartridge through solid-phase extraction. Prior to analysis on GC-ECD, the cleaned extracts were concentrated again.
In the second part of the thesis, the following four extraction techniques of PCBs from plastic resin pellets were compared: Soxhlet extraction, PFE, ultrasonication and maceration. The obtain results have shown that the best efficiency and repeatability of extraction is achieved with PFE. In case of Soxhlet extraction, the results were unrepeatable. Maceration and ultrasonication had 40-45 % lower extraction efficiencies than PFE.
Najdeno v: ključnih besedah
Ključne besede: PCB, plastic resin pellets, pressurized fluid extraction, Soxhlet, maceration, ultrasonication, microplastics
Objavljeno: 22.06.2017; Ogledov: 3846; Prenosov: 195
Polno besedilo (1,95 MB)
Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type AnalysisŠpela Koren
, Manca Kovač Viršek
, Petra Makorič
, Maryline Pflieger
, 2017, pregledni znanstveni članek
Opis: Plastic resin pellets, categorized as microplastics (≤5 mm in diameter), are small granules that can be unintentionally released to the
environment during manufacturing and transport. Because of their environmental persistence, they are widely distributed in the oceans and
on beaches all over the world. They can act as a vector of potentially toxic organic compounds (e.g., polychlorinated biphenyls) and might
consequently negatively affect marine organisms. Their possible impacts along the food chain are not yet well understood. In order to assess the
hazards associated with the occurrence of plastic pellets in the marine environment, it is necessary to develop methodologies that allow for rapid
determination of associated organic contaminant levels. The present protocol describes the different steps required for sampling resin pellets,
analyzing adsorbed organochlorine pesticides (OCPs) and identifying the plastic type. The focus is on the extraction of OCPs from plastic pellets
by means of a pressurized fluid extractor (PFE) and on the polymer chemical analysis applying Fourier Transform-InfraRed (FT-IR) spectroscopy.
The developed methodology focuses on 11 OCPs and related compounds, including dichlorodiphenyltrichloroethane (DDT) and its two main
metabolites, lindane and two production isomers, as well as the two biologically active isomers of technical endosulfan. This protocol constitutes
a simple and rapid alternative to existing methodology for evaluating the concentration of organic contaminants adsorbed on plastic pieces.
Najdeno v: ključnih besedah
Ključne besede: Environmental Sciences, Issue 125, Microplastics, resin pellets, pesticides, persistent organic pollutants, organochlorine pesticides, dichlorodiphenyltrichloroethane, endosulfan, hexachlorocyclohexane, lindane, Fourier transform infrared spectroscopy, pressurized fluid extractor
Objavljeno: 10.07.2017; Ogledov: 3086; Prenosov: 0