Biodegradable plastics are not as green as they were previously thought to be, according to a report of the United Nations, entitled “MARINE PLASTIC DEBRIS AND MICROPLASTICS”.
The new report of the UN says that the rate at which biodegradable plastics break down is extremely slow. Some of them need very high temperatures to actually degrade, and therefore, if they end up in the ocean (and they do), they might stay there forever – not much biodegradable, right? When they do remain in the ocean, they are similar to their other counterparts in the sense that they pollute too.
These biodegradable plastics will degrade at around 50 degrees Celsius, says UN Environment Program scientist Jennifer McGlade in a statement to The Guardian. The problem is that the ocean does not reach this temperature, and nor can the plastics be degraded by UV as they sink to the floor of the ocean instead of remaining afloat to be exposed to the sun.
The report goes further to say that assigning the term ‘biodegradable’ to plastic products can even contribute to more pollution because people will tend to think of them as less harmful than the normal plastics, when there is no great difference between the two.
All goes to say that the term itself is “semantically complicated”, as pointed out by professor Frederick Michel in an article of The Christian Science Monitor. Explaining his statement, he says that, for instance, polyethylene will biodegrade up to 0.1% in one decade in soil.
“Is it therefore biodegradable? Probably not,” says Michel.
The report reiterates the detrimental effects of plastics on our environment: for example, they will often be caught in marine animals like turtles and sharks while smaller pieces thereof can get ingested by birds and fish, leading to their death.
If biodegradable plastics are no more a solution, what should be done to remediate the situation? Professor Michel explains that (real) biodegradable materials should be those that completely break down to carbon dioxide, and materials naturally found in nature within a certain time limit, from six months to one year, depending on the location. He mentions that some forms of bioplastic are able to degrade under different conditions.
Meanwhile, scientists are attempting to develop biodegradable plastics that can also be edible, so that they do not result in harm if ingested by animals. Innovation in the field is hoped to counter the current harm posed by plastics. The UN, however, emphasises in its report that the most important point is for countries and individuals to curb plastic pollution in oceans by having a better waste management and collection to prevent the plastics from even getting into the sea.