Resource or waste? A perspective of plastics degradation in soil with a focus on end-of-life options

‘Capable-of-being-shaped’synthetic compounds are prevailing today over horn,bone, leather, wood, stone, metal, glass, or ceramic in products that werepreviously left to natural materials. Plastic is, in fact, economical, simple,adaptable, and waterproof. Also, it is durable and resilient to natural degradation(although microbial species capable of degrading plastics do exist). In becoming awaste, plastic accumulation adversely affects ecosystems. The majority of plasticdebris pollutes waters, accumulating in oceans. And, the behaviour and the quantityof plastic, which has become waste, are rather well documented in the water, infact. This review collects existing information on plastics in the soil, payingparticular attention to both their degradation and possible re-uses. The use ofplastics in agriculture is also considered. The discussion is organised according totheir resin type and the identification codes used in recycling programs. In addition,options for post-consumer plastics are considered. Acknowledged indicators do notexist, and future study they will have to identify viable and shared methods tomeasure the presence and the degradation of individual polymers in soils.