Aquatic ecotoxicologist Marco Vighi is studying the water cycle in agriculture and presence of plastics. He shares vital information with listeners such has The different sizes and sources of plastic in our water such as micro, macro, and nano plastics; The concern for acute aquatic toxicity and why our inability to measure nano plastics is concerning; and What we do know about the types of plastic sources that harm marine wildlife. Former professor and researcher Marco Vighi works with the IMDEA Water Institute studying acute aquatic toxicity and ecology risk assessment. He's following the water cycle in agriculture, from rivers to irrigation to agricultural application and back to surface water. He begins by explaining it is better to understand in general the origin of micro plastics and consider that nano plastics are the unknown—we don't know anything about their presence because we don't have the tools to measure them or know if they are crossing cell barriers. He explains to listeners that there are two types of micro plastics: first, ones that are intentionally produced at a micro level for products like cosmetics and toothpaste; and second, non-intentionally produced micro plastics derived from the fragmentation of bigger plastics, from synthetic clothing fibers, and from roadside products like tire pieces. He adds that while regulations are in play for the first type, which is less concerning, there is little in the way to control the second type. He explains more about the technical aspects of how these plastics fragment, how ubiquitous they are, and additional struggles with understanding nano plastic activity.  For more information, he urges listeners to comb through information with care, learning what is accurate and what isn't. Finally, he says that packaging makes up the majority of harmful plastic and is a source that we can replace with alternate  materials and must tackle.  For more about Marco Vighi, see https://www.water.imdea.org/about-us/people/researchers/marco-vighi.