Another key observation is that academic institutions dominate both journal and patent publication; this suggests that the methods to prevent or remediate microplastic pollution have not translated into commercial applications. It is not atypical for newer topics to be identified and thoroughly explored first by academic institutions and research groups before becoming an interest to the private sector. However, the lack of industrial publications may also indicate that there is not sufficient technical development, or economic incentive to address microplastic pollution. The CAS Content Collection also records the substances used in each individual document. With this information, we are able to obtain the top registered substances in microplastic research (Fig. ). It is of no surprise that the top 5 substances are ethene homopolymer (polyethylene), polystyrene, 1-propene homopolymer (polypropylene), polyethylene terephthalate (PET), and polyvinyl chloride (PVC). These correlate to the standard polymer composition of studied microplastics in the environment. Cellulose, as a biobased polymer, appears at high frequency in these documents, mostly due to being used as a replacement of synthetic polymers in applications such as electronics, composites, applications in the biomedical field, sustainable biomaterials, textiles, and to remove microplastics from the environment, etc. Cellulose is also considered a microplastic in some studies, especially modified or regenerated cellulose in the form of rayon or cellophane particles.