The plastic and its usage has its supporters and critics, with both making good points, as the plastic is a material that both has its big advantages, but also its big disadvantages.
The main advantages of the plastic is that it is very cheap, the products with it are very easy for production, and it can be recycled numerous times. Also, it is very easy and practical for usage.
The main disadvantages are that the plastic needs lot of time to dissolve, depending on the type of plastic it can be anywhere from few hundred to few thousands years. Also, when it disposes it releases a lot toxic chemicals into the soil, and those chemicals are very harmful for the living organisms.
Big problem is also that most of the plastic is not being recycled, but it is thrown away, so there's enormous plastic waste everywhere in the world. Big portion of it is burned, and by burning it lot of toxic chemicals are released into the air, and that causes lot of pollution.