How much plastic is too much plastic?
Over the past few years, a large number of studies have been published reporting the presence of microplastics in a wide variety of environments. Plastic has reached remote places like Antarctica is has also been found in our food, directly exposing us to its potential toxic effects. When these studies reach the public, it is often overlooked that plastics, as particulate materials, do not have a single exposure metric. (...)
Plastic in the air we breathe
In a previous post, it was explained that anthropogenic aerosol also contains microplastics, which, depending on their size, can remain suspended for a long time. As with other forms of plastic pollution, humans are responsible for releasing these particles into the environment, making areas with higher population densities the main sources of emissions. (...)
Plastic falling from the sky
There is also plastic in the atmosphere. It is part of a group of particles known as atmospheric aerosol. These are small solid or liquid particles suspended in the air, with diameters typically ranging from 1 nm to 10 μm (from one nanometre to ten microns). These diameters correspond to nanoscale-sized molecules, such as organic molecules, or to particles like pollen, sand, or salt, which can reach sizes of microns or larger. (...)
Uses of Bioplastics
According to European Bioplastics, the global production of bioplastics is around 2.2 million tons (data from 2022), which represents less than one percent of the over 390 million tons of plastic produced annually (Plastics Europe for 2021, Plastics – The Facts, 2022). Within these 2.2 million tons, approximately one million correspond to non-biodegradable but bio-based plastics, mainly polyethylene (PE), polyamides (PA), and poly(trimethylene terephthalate) (PTT). (...)
How biodegradable are biodegradable plastics?
In a previous post, the different types of bioplastics were introduced. It was shown that bioplastics constitute a family of materials that includes bio-based and biodegradable materials. When both characteristics occur simultaneously, the bioplastic, being both bio-based and compostable at the same time, is referred to as BioCom. It is important to emphasize the distinction between ‘biodegradable’ and ‘compostable’. (...)
What is a bioplastic?
Most of the plastics we currently use come from fossil sources. In other words, the carbon they contain comes from petroleum-derived products. As a result, their degradation releases into the environment carbon previously trapped underground. The steady increase in carbon dioxide concentration in the atmosphere since the Industrial Revolution is an undeniable fact. (...)
Plastic waste, circularity, and recycling
The global economic order is built upon the exploitation of numerous non-renewable resources. The unsustainability of this model in the long term is increasingly hard to ignore and is evident not only in the depletion of raw materials but also in numerous negative impacts on the environment. In 1972, an essential book on this topic was published. It is called ‘The Limits to Growth’, written by various scientists from the Massachusetts Institute of Technology at the request of the Club of Rome. (...)
Synthetic, artificial, and natural fibers
A fibre can be informally defined as a particle in which one of its dimensions is considerably larger than the other two, which are also equal or very similar to each other. However, the precise definition of a fibre in the context of research on plastic contaminants requires additional explanations. The Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP) considers a synthetic polymer particle to be a microplastic if its larger dimension is below 5 mm and not below 1 µm. (...)
Synthetic, semi-synthetic, natural and artificial polymers
The concept of microplastics is reasonably well established. As mentioned in other posts, microplastics are plastic particles whose major dimension falls within the range of 1 to less than 5000 microns (5 mm). However, it is important to provide some clarifications regarding what constitutes a plastic for regulatory and environmental purposes, as the term ‘plastic’ corresponds more to common language than to scientific terminology. (...)
Size matters, but it’s not the only thing that matters
Size defines a microplastic. As mentioned earlier, a solid particle is considered a microplastic when its main component is a synthetic organic polymer, and its size, measured as its major dimension, falls between 1 µm and < 5 mm. However, size is not the only important information about microplastic particles. Along with size, it’s common to include descriptors that help understand the material’s origin. (...)
What is and what is not a microplastic
If we ask a random person what a microplastic is, they might respond that it’s something that can only be seen with a microscope. The answer is both yes and no, and this may be surprising, because in this neologism, science and common sense don’t entirely align. Let’s start with the definition. The word ‘microplastic’ was set to refer to the small plastic fragments that have become one of the main threats to the environment and human health. (...)
Ocean gyres and plastic 'islands'
It’s easy to come across information that refers to the 'plastic islands' supposedly accumulating in the world’s oceans. Even in seemingly reputable sources, images like the one below frequently appear. This particular one is accompanied by the caption '300-Mile Swim Through The Great Pacific Garbage Patch Will Collect Data On Plastic Pollution' and it appears to depict a buildup of garbage in one of the seven plastic islands located in the five major gyres, which I will mention below, along with additional accumulations in the Sargasso and Barents Seas. (...)