Article states this is “plastic that otherwise would be dumped in the city’s overflowing garbage heaps.” Environmental impact of these plastics should be weighed relative to the impact of those same plastics sitting in said garbage heaps. It’s likely safer sequestered in a processed brick optimized for durability than it would be rapidly degrading from e.g. thin plastic bag material into microplastics leaching into the soils and water tables around the dump.