Microplastic
(Photo: shutterstock)
“Previous studies have already shown the presence of microplastics in the atmosphere in areas near the shoreline,” says Dr. Miri Trinik of the research groups of Prof. Ilan Koren of the Department of Earth and Planetary Sciences and Prof. Assaf Vardi of the Department of Plant and Environmental Sciences. “We were amazed to discover a significant amount of micro-plastic over parts of the ocean that are considered ‘virgin’.”
Professors Vardi and Koren’s research groups – together with Prof. Yinon Rudich of the Department of Earth Sciences and Planets – have been collaborating for years in trying to understand the interface between the ocean and the atmosphere. As part of these research efforts, in 2016 Dr. Mitchell Flores was sent on a voyage of the research ship “Tara” in the North Atlantic and collected, among other things, particle samples in the air above these remote areas of the ocean.
The sailing ship “Tara”. The measuring equipment was placed at the top of the queue
(Photo: From the newsletter of the American Meteorological Association)
When the samples arrived at the Weizmann Institute of Science, the researchers found that identifying the microplastics in the samples was far from easy. To understand exactly what types of plastics penetrated the atmosphere, the researchers turned to faculty scientist Dr. Ido Pinkas, an expert in a technique known as Raman spectroscopy in the Department of Chemical Research Infrastructures. The scientists’ value – and which took into account the shape of the particles, their mass, wind directions over the ocean and their speed – revealed that the microplastic originated in the samples was probably in plastic bags and other plastic waste dumped on the shores and making its way hundreds of miles to the ocean.
Seawater samples in those areas revealed a similar composition of plastic particles. This fact reinforces the hypothesis that microplastic particles penetrated the atmosphere as a result of spraying seawater or were carried by the wind and transported by air currents to distant parts of the ocean.
“When microplastic particles are in the air, they dry out, are exposed to UV radiation and have chemical interactions with various atmospheric components,” says Dr. Trinik. “This means that the particles that find their way back to the ocean may be harmful or even more toxic to marine organisms that swallow. Them. “Prof. Vardi adds:” Plastic in the sea serves as a breeding ground for bacteria. “When the particles are carried in the wind, they may be carriers of marine bacteria, including pathogens that can harm both marine organisms and humans.”
More on this topic: The boy who wants to collect microplastics
(Photo: Angle, Science and Environment News Agency)
Scientists estimate that the true amount of microplastics above the oceans is much larger than what was revealed in the measurements, as their systems could not detect particles below a certain size. Particle size has a fateful meaning: not only are smaller particles likely to stay in the air longer, but the likelihood that they will be eaten (but will not be eaten) by tiny marine creatures, increases as they get smaller.
“And there is another important ecological aspect: like all particles carried in the air, microplastic particles actually become part of the material cycles in nature – for example carbon and oxygen cycles,” says Prof. Koren and ends with a pessimistic forecast: “Even if we stop polluting the beaches tomorrow morning, we are “Seeing more and more micro-plastic particles is being released into the atmosphere – as it takes time for the plastic waste that has already found its way into the sea to crumble into particles.”