We live nestled within a veritable petrochemical cocoon. From dawn, when we squeeze viscous plastic toothpaste onto nylon bristles, to dusk, when we microwave food in BPA-free plastic, plastic encapsulates our lives. It’s a relationship we scarcely question as we gladly accept plastic’s ubiquitous presence.
The world has long been dependent on petroleum-based plastics. They are cheap, durable, and versatile, finding applications from healthcare to consumer goods. Plastic has historically been an affordable material to produce and use, largely due to the relatively low cost of oil. However, the environmental toll is immense, and with rising oil prices approaching US $100 per barrel for Kuwait Export Blend on 15th September 2023, The economics behind plastics are being reevaluated. This brings us to a crucial comparison: petroleum-based plastics vs. bioplastics.
A crude oil component called ‘naphtha’ is at the core of plastic production. The proportion of naphtha (from naphthenes) in crude oil can vary based on the specific type of oil, but it generally constitutes between 15% and 30% of the crude oil by weight. Consequently, even if there is a decline in the demand for oil for heating and powering internal combustion engine vehicles, our existing or increasing need for petroleum-based plastics necessitates continued oil extraction at current levels.
The True Cost of Petroleum-Based Plastics
Petroleum-based plastics generally range from US $1 to US $5 per kilogram. However, these prices are influenced by fluctuating oil prices. When oil exceeds US $100 a barrel, the cost of producing petroleum-based plastics can increase significantly, possibly reaching upwards of US $6 or US $7 per kilogram. For context, 1.9 kilograms of crude oil is required for 1 kilogram of plastic.
What often goes unmentioned are the hidden environmental and public health costs. From carbon emissions during production to microplastics contaminating water bodies, the externalities are far-reaching. In the context of global public health, the long-term impact could be costly treatments for diseases triggered by environmental degradation. Considering these hidden costs, it’s clear that we need to reevaluate our reliance on petroleum-based plastics. Enter the promising alternative: bioplastics.
Consider the Great Pacific Garbage Patch. This floating “island” of plastic debris in the Pacific Ocean spans an area twice the size of Texas. It consists primarily of microplastics — tiny particles that fish often mistake for food. Not only does this harm marine life, but these plastics also enter the food chain, ultimately consumed by humans. Studies have shown that microplastics can carry harmful pathogens and toxic chemicals, which raise serious concerns for global public health.
The Cost of Bioplastics: More Than Just Numbers
As we look for ways to mitigate the environmental impact of our consumption habits, a crucial question arises: are people willing to pay a little more for bioplastics to promote sustainability? Bioplastics are usually more expensive, ranging from around US $2.5 to US $15 per kilogram. This is partly due to less mature production processes and smaller economies of scale. Bioplastic prices are expected to drop as production and distribution processes become more streamlined. For example, the price of Polylactic acid (PLA) has fallen by 50 percent since its introduction in 2007, with an average drop of 9 percent annually.
Bioplastics are a revolutionary subset of plastics that have piqued interest for their environmentally friendly pedigree. Unlike traditional plastics, predominantly synthesised from fossil fuels like petroleum, bioplastics are crafted from renewable biological resources. These can range from corn starch and sugarcane to more avant-garde materials like algae. This shift in raw materials has profound implications for sustainability. Among these next-gen materials, PLA bioplastic is a prime example of how far we’ve come in creating eco-friendly alternatives.
PLA bioplastic is a versatile material with a wide range of applications. It’s commonly used in food packaging, including containers, cups, trays, and packaging films and wraps. Beyond packaging, PLA is ideal for creating utensils, shopping bags, and rubbish (or trash) bags. It’s also used in plant pots, textiles and fabrics. For the tech-savvy, PLA is a popular filament in most 3D printers, prized for its detailed printing capabilities. In the medical field, PLA is highly valued for implants and sutures, as it breaks down harmlessly in the body over time. Additionally, it’s a material found in various consumer goods, from toys and cellphone cases to sunglasses frames.
However, bioplastics often boast a reduced carbon footprint and lesser environmental impact, aligning more closely with sustainability objectives. This is a crucial consideration when integrating public health goals and environmental responsibility. In particular, bioplastics offer a reduction in carbon emissions from fossil fuel-based materials. The production of bio-based plastics requires up to 90 percent less energy than traditional plastics and has the potential to reduce greenhouse gas emissions by as much as 80 percent.
One such example is the case of NatureWorks LLC, a leading company in producing Ingeo biopolymer, which is made from plants like sugarcane. According to studies and life cycle assessments conducted on their bioplastics, NatureWorks found that their Ingeo biopolymer could produce up to 60–80% less greenhouse gases and consume approximately 50% less non-renewable energy during production than traditional plastics like PET and PS.
Are all bioplastics sustainable?
It’s essential to note that not all bioplastics are equally sustainable. The source of the biological material, the agricultural practices involved, and the biodegradability of the final product are all factors that need to be scrutinised. For instance, corn is a monoculture crop, often grown in vast fields requiring significant synthetic fertiliser and pesticide inputs. These chemicals can run off into waterways, leading to nutrient pollution and other environmental issues. The energy used for planting, cultivating, and harvesting the corn also contributes to its environmental footprint. And let’s remember the ethical concerns related to using food-grade corn for plastic production while food insecurity remains a problem in many parts of the world.
Theoretically, bioplastics made from agricultural byproducts, such as corn or sugarcane, are more sustainable than those derived from food crops. But it’s important to note that food crops can be grown on land suitable for other purposes, such as grazing pastures and forests. Thus, if we were to use these crops for bio-based plastics instead of human consumption, we would need additional land to meet global demand.
Bioplastics often have a lower carbon footprint during production compared to petroleum-based plastics. Plants absorb CO2 as they grow, offsetting some emissions generated during production. However, it’s essential to consider agricultural practices, such as pesticide use and land conversion, which can add to the environmental impact.
However, curbside recycling is increasingly a common practice. You can typically dispose of bioplastics in your curbside recycling bin. Many communities have separate bins for plastic and paper collected weekly in a local curbside recycling program.
Bioplastics can require significant amounts of water and energy during production. In some cases, energy might come from non-renewable sources, negating some environmental benefits. However, a 2009 study found that one type of corn-based bioplastic requires significantly less energy than traditional plastics made from petroleum.
Companies might market bioplastics as “green” or “eco-friendly,” but the environmental benefits vary widely. This can mislead consumers and stakeholders, especially those keen on making sustainable choices.
Carbon sequestration — another perspective
While bioplastics have been spotlighted for their potential to reduce dependency on fossil fuels and lower carbon footprints, it’s crucial to recognise other innovative strategies to mitigate environmental impact. One such promising avenue explores the possibilities of Carbon Sequestration — a concept that goes beyond mere storage of CO2 to its productive utilisation.
CO2 from carbon sequestration or carbon capture and storage (CCS) can be turned into plastic. There are several different ways to do this, but they all involve using catalysts to convert the CO2 into other chemicals that can then be used to make plastic. This process is called carbon capture and utilisation (CCU). Plastic is just one product; others include synthetic fuels, building materials and fertiliser.
While still an emerging area, companies like Newlight Technologies are pioneering this space. Newlight uses carbon capture technology to convert greenhouse gases like methane and CO2 into a bioplastic material called AirCarbon. This material is then used in everything from furniture to packaging, effectively sequestering the carbon and reducing the product’s overall carbon footprint
Alternatively, using a catalyst to convert CO2 into ethylene a basic building block for many plastics. This can be done using various catalysts, such as nickel and cobalt. Once the CO2 has been converted into ethylene, it can be used to make a variety of plastics, such as polyethylene and polypropylene.
Another approach is to use a catalyst to convert CO2 into propylene, another basic plastic building block. This can also be done using a variety of different catalysts. Once the CO2 has been converted into propylene, it can be used to make a variety of plastics, such as polypropylene and polystyrene. Given that propylene is one of the most widely used plastic materials globally, even a small percentage shift to a more sustainable production method could have significant global implications.
When Oil Prices Skyrocket: A Comparative Analysis
As oil prices continue their unpredictable dance, close to hitting the US $100 mark or more, the financial landscape for plastics is dramatically shifting. The spike in oil prices directly affects the cost of production for petroleum-based plastics, making them less economically appealing. On the flip side, this creates a golden opportunity for bioplastics to become not just an environmentally responsible choice but a financially prudent one.
High oil prices can serve as a catalyst for change, forcing industries to reevaluate their material choices. In sectors like healthcare, where both plastics are widely used, this reevaluation could lead to more sustainable practices that resonate with broader public health and climate goals.
While petroleum-based plastics have long been the default choice due to their affordability and versatility, the changing landscape of oil economics and the urgent need to tackle climate change make it imperative to consider bioplastics an increasingly viable alternative. As we evaluate these options, understanding the nuanced monetary and environmental costs is crucial for making decisions that align with economic sustainability and ethical responsibility. The time for reevaluation is now; the choices we make today will sculpt the future we will live in. What kind of plastic will shape your future? The answer to this question can propel us all towards a more sustainable, healthier planet.