Guest post by Josh Hill

Plastic is a problem; it has penetrated every corner of the globe: the depths of the ocean and even arctic ice. But now we face a new threat, often invisible to the naked eye -- a form of plastic that is in our drinking water, the dirt we walk on and even the air we breathe!

I am talking about microplastics, tiny fragments of plastic that pollute the environment. But, where do they come from? Why are they a problem? And what can we do about them?