The two most well-liked alternatives to single-use plastics at the moment are paper and polylactic acid (PLA). Paper and bio derived plastics like PLA and many other 'plant-based' compostable substitutes may both be significant greenhouse gas emitters, even though PLA is only biodegradable in industrial composting facilities.

evaluating plastic in comparison to its common substitutes

Using paper as an example, study after study demonstrates that paper shopping bags have a far higher carbon footprint than traditional plastic bags. Paper bags do, in fact, lessen the negative effects of littering than single-use plastic bags when it comes to climate change, eutrophication, and acidification, according to a meta-analysis of seven life cycle assessments (LCAs) carried out by UNEP in 2020. Similar findings were obtained from a different study that contrasted the use of conventional low-density polyethylene (LDPE) shopping bags with compostable plastic supermarket bags. 

The amount of energy needed to produce the same quantity of biodegradable plastic bags and paper bags was approximately three times that of standard plastic bags. Similar to the conventional plastic bag, these bags produced greenhouse gas emissions that were up to three times higher. Similar patterns were found in a small comparative LCA study that contrasted paper and PLA drinking straws with single-use plastic drinking straws, which are the latter's two most popular substitutes. 

Comparing the energy demands of PLA and paper straws, the single-use plastic straw was almost half as energy-intensive. Like the single-use plastic straw, the PLA and paper straws had a nearly three-fold higher global warming potential than the latter. The study also discovered that using a (reusable) metal straw would only be significantly less harmful than using a plastic straw if the metal straws were washed with cold tap water and the usual cleaning time was reduced by half after each use. 

The utilisation of naturally occurring carbon dioxide absorbing materials, such as seaweed, could revolutionise the markets for plastic alternatives, given that the major component of single-use straws was responsible for the biggest portion of the carbon footprint. In order to do this, a preliminary evaluation determined that the net carbon dioxide sequestration potential of a seaweed-based straw prototype by LOLIWARE Inc. was lower than that of all other conventional straws. According to this study, a typical plastic straw emits 95% less carbon dioxide over the course of its lifetime than a seaweed-based straw does. 

As a result, the seaweed-based straw has the potential to be either carbon neutral or even carbon negative depending on how the product's life cycle is taken into account during its development, manufacturing, and end-of-life scenarios. Seaweed is a well-rounded contender to replace plastic because of this as well as the contribution it makes to the financial well being of millions of people in coastal communities across the world, particularly women.

Using a science-based plastic policy package, one can achieve net-zero emissions.

Plastic manufacturing is being pushed up to double by 2040, as the globe struggles to achieve the goals of the Paris Agreement and divest from fossil fuels. Particularly in the fossil fuel sector, investments in plastics have been made in an effort to diversify revenue streams and use the profits to pay for the expensive fixed-cost infrastructure erected around oil refineries. 

The effect of plastics on climate change will need to be at the front of the agenda now that world leaders are working on finalising the provisions of a worldwide convention on plastic pollution modelled after the Paris Agreement that was decided upon at the United Nations Environment Assembly in Nairobi last week. The Paris Agreement-style worldwide convention against plastic pollution that was decided upon at the United Nations Environment Assembly in Nairobi last week is now being written by world leaders, so the effect of plastics on climate change must be prioritised.

The treaty would have to mandate that states unite around establishing ambitious goals to address plastic pollution from a life-cycle viewpoint, including reductions in plastic manufacture, and be founded in the ideals of environmental justice and human rights. Bans on single-use plastics like drinking straws have existed for a while, with the goal of decreasing or eliminating their use, at the country, city, and establishment levels.