There is an increasing awareness of the threats posed by the worldwide presence of microplastics (MPs) in the environment. Due to their high persistence, MPs will accumulate in the environment and their quantities tend to increase with time. MPs end up in environments where often also chemical contaminants are present. Since the early 2000s, the number of studies on the sorption of chemicals to plastic particles has exponentially increased. The objective of this study was to critically review the literature to identify the most important factors affecting the sorption of chemical contaminants to MPs. These factors include the physicochemical properties of both the MPs and the chemical contaminants as well as environmental characteristics. A limited number of studies on soil together with an increased notion of the importance of this compartment as a final sink for MPs was observed. Therefore, we assessed the distribution of model chemicals (two PCBs and phenanthrene) in the soil compartment in the presence of MPs using a mass balance model. The results showed a high variation among chemicals and microplastic types. Overall, a higher partitioning to MPs of chemical contaminants in soil is expected in comparison to aquatic environments. As sorption to a large extent determines bioavailability, the effects of combined exposure to chemicals and MPs on the toxicity and bioaccumulation in biota are discussed. Finally, some considerations regarding sorption and toxicity studies using MPs are given.
- MeSH
- biologická dostupnost MeSH
- chemické látky znečišťující vodu analýza MeSH
- chemické modely MeSH
- fenantreny analýza MeSH
- lidé MeSH
- monitorování životního prostředí MeSH
- plastické hmoty analýza MeSH
- polychlorované bifenyly analýza MeSH
- půda chemie MeSH
- společenstvo MeSH
- vystavení vlivu životního prostředí škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Artificial soil (AS) is used in soil ecotoxicology as a test medium or reference matrix. AS is prepared according to standard OECD/ISO protocols and components of local sources are usually used by laboratories. This may result in significant inter-laboratory variations in AS properties and, consequently, in the fate and bioavailability of tested chemicals. In order to reveal the extent and sources of variations, the batch equilibrium method was applied to measure the sorption of 2 model compounds (phenanthrene and cadmium) to 21 artificial soils from different laboratories. The distribution coefficients (Kd) of phenanthrene and cadmium varied over one order of magnitude: from 5.3 to 61.5L/kg for phenanthrene and from 17.9 to 190L/kg for cadmium. Variations in phenanthrene sorption could not be reliably explained by measured soil properties; not even by the total organic carbon (TOC) content which was expected. Cadmium logKd values significantly correlated with cation exchange capacity (CEC), pHH2O and pHKCl, with Pearson correlation coefficients of 0.62, 0.80, and 0.79, respectively. CEC and pHH2O together were able to explain 72% of cadmium logKd variability in the following model: logKd=0.29pHH2O+0.0032 CEC -0.53. Similarly, 66% of cadmium logKd variability could be explained by CEC and pHKCl in the model: logKd=0.27pHKCl+0.0028 CEC -0.23. Variable cadmium sorption in differing ASs could be partially treated with these models. However, considering the unpredictable variability of phenanthrene sorption, a more reliable solution for reducing the variability of ASs from different laboratories would be better harmonization of AS preparation and composition.
The study is focused on artificial soil which is supposed to be a standardized "soil like" medium. We compared physico-chemical properties and extractability of Phenanthrene from 25 artificial soils prepared according to OECD standardized procedures at different laboratories. A substantial range of soil properties was found, also for parameters which should be standardized because they have an important influence on the bioavailability of pollutants (e.g. total organic carbon ranged from 1.4 to 6.1%). The extractability of Phe was measured by supercritical fluid extraction (SFE) at harsh and mild conditions. Highly variable Phe extractability from different soils (3-89%) was observed. The extractability was strongly related (R(2)=0.87) to total organic carbon content, 0.1-2mm particle size, and humic/fulvic acid ratio in the following multiple regression model: SFE (%)=1.35*sand (%)-0.77*TOC (%)2+0.27*HA/FA.
- MeSH
- buněčné linie MeSH
- fenantreny analýza MeSH
- infračervené záření MeSH
- kultivační média MeSH
- lidé MeSH
- lipidy izolace a purifikace MeSH
- nádory úst MeSH
- nádory MeSH
- skot MeSH
- spektrofotometrie MeSH
- thymus cytologie MeSH
- tkáňové extrakty farmakologie MeSH
- ultrafialové záření MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- skot MeSH
- zvířata MeSH