Sea-borne Plastics

Two articles have passed before my eyes recently that, taken together, present a worrying picture.

The first details the incredible build up of rubbish, most of it plastic, on Henderson Island, an uninhabited piece of land just 5 km wide located between Australia and South America. A recent expedition there found some 38M items of rubbish, in all weighing approximately 18 tonnes. On the beaches were an average of 239 items of junk per square metre. Much of this material is decades old attesting to the generally slow degradation of plastic.

The other article argues that there is actually much less plastic in the ocean than expected. The authors also note that the total amount in the waters appears to have plateaued, a situation that is difficult to explain by purely physical processes. They go on to proposed that this situation may be the result in an increase in the population of microbes with the ability to biodegrade plastic. (There is a counter argument that plastic is simply sinking to the sea bed as colonising organisms weigh it down). Even if the degradation hypothesis is correct it may still not be good news - all that may be happening is that the potentially harmful additives that are contained within many plastic are being released into the environment at an ever increasing pace.

So - there is a huge amount of junk floating around out there; and there is an even greater quantity of "missing" junk from which unpleasant chemicals may be being released. It's time to reinvigorate the old mantra - "reduce, reuse, recycle".