We use cookies on our website. Some are necessary for the operation of the website. You can also allow cookies for statistical purposes. You can adjust the data protection settings or agree to all cookies directly.
Data Protection Declaration
Imprint
Uptake and effect of nano- and microplastics in the intestine and liver
Project
Project code: BfR-LMS-08-1322-675
Contract period: 01.01.2017
- 31.12.2017
Purpose of research: Applied research
Microplastic are plastic particles with a diameter of one micrometer to five millimeters. They are an environmental pollutant due to the increasing use of plastics in the last decades. Microplastic can be divided into two different types: primary microplastic is intentionally produced in this size range as an ingredient for different purposes. Secondary microplastic results from fragmentation processes of plastic products due to different environmental factors like salt water, UV radiation and mechanical impact. It is the most common type of microplastic. In the seas, biofouling and biofilm formation on the surface of these small particles causes them to sink down. Microplastic was found in different waters and oceans, on beaches and in the digestion tract of different marine organisms. The detection of plastic particles in aquatic samples is based on filter systems collecting particles with a size bigger than 1 µm and mostly on microscopic detection. This method, however, misses smaller particles. It can be expected that the degradation process does not stop at the micron sale and hence also nanoplastic can be formed. The most important polymer types are polyethylene (PE), polypropylene (PP) and polystyrene (PS). On average, 4% of the weight of the particles consists of additives; half of them are plasticizers. Moreover, the plastic particles can contain monomers or adsorb persistant organic pollutants (POPs) like polycyclic aromatic hydrocarbons (PAH). This adsorption is most likely even higher for smaller particles due to the grater surface to volume ratio. Also inorganic substances like metals can be accumulated. In the literature, there are many environment-related studies concerning microplastics. In vivo studies and in vitro studies on different models of the intestinal epithelia are dealing with the oral uptake of micro- and nanoplastics. They show that plastic particles are partly bioavailable. Uptake and transport depend on particle size and surface modification. In some but not all animal studies particles were found in the liver, spleen and kidney. The immune system of the intestine with the Peyer's patches and their M-cells which are specialized on antigen uptake play the most important role in particle uptake. The intestinal mucus layer might have a protective role. Most of these studies use polystyrene particles as model particle, as they are the easiest to produce in every size and their surface can be easily modified. Moreover, they are commercially available and can be stained with different fluorescent dyes. However, they do not represent the most common materials. Beside the investigation of uptake and bioavailability, toxicity and toxicological effects have been of minor interest in the past. Many environmental toxicity effects in aquatic model organisms are caused by a lack of nutrition due to an overload of the digestion system with plastic particles. One in vivo experiment with chicken showed a reduction in iron uptake that could be compensated over time. In the context of the above described context, this project will focus on the uptake and effect of micro- and nanoplastics in intestine and liver. Therefore, different in vitro models for intestinal epithelial cells (Caco-2 mono- and co-culture) and liver hepatocytes (HepG2 or HepaRG) are used. Used particles are differently sized polystyrene particles as well as particles made of the most important materials. Endpoints of interest are cell viability, uptake and transport of particles.
Section overview
Subjects
- Toxicology
