Tag Archives: microplastics carry bacteria

Yummy Plastics

“From Waste to Food: A Generator of Future Food” by Ting Lu and Stephen Techtmann, won the Merck 1 million prize.  It concerns an efficient, economical and versatile technology that converts wastes such as end-of-life plastics into edible foods. These foods contain all the required nutrition, are non-toxic, provide health benefits, and additionally allow for personalization needs. This technology promises to transform waste streams into nutritious food supplements, thus solving the two problems of increasing food scarcity and plastic waste simultaneously.

The core of the proposed technology is to harness synthetic microbial consortia – a combination of natural and rationally engineered microorganisms – in order to efficiently convert waste into food. The project will comprise four research goals: conversion from polyethylene terephthalate (PET) to protein powder (goal 1), augmentation of biosafety for food and for the environment (goal 2), introduction of nutritional and health-promoting contents (goal 3), and expansion of the technology to include additional plastics or other types of waste (goal 4). The proposed work will establish a transformative basis for food generation.

  • Excerpts from Future Insight Prize, Merck Press Release, July 13, 2021

Junk: the Engine of Green Growth

“Plastic waste is not just a global crisis that threatens economic recovery, climate, and nature. It is also an investment opportunity that can flip it from a scourge into an engine for economic development,” said Rob Kaplan, who founded Circulate Capital in 2017. Initially the firm sought to back companies in India and Southeast Asia, such as recycling or waste-sorting companies, that help reduce the amount of plastic waste that winds up in the ocean.

In 2019 it raised a $106 million debt and project finance fund, Circulate Capital Ocean Fund, backed by a handful of large multinational corporations that include Coca-Cola, Danone,  Procter & Gamble,  and Unilever…Circulate is one of a small but growing number of firms investing in companies that contribute to what they call the circular economy, a business model that seeks to eliminate waste that organizations produce, continuously reuse products and materials and regenerate natural systems.

An estimated 30 private-market funds, including private-equity, venture and debt strategies focused on the circular economy in the first half of 2020, up from just three in 2016….A number of large multinational corporations are funding these firms’ efforts as part of a broader push to reduce both the overall waste their own companies produce and the amount of virgin materials they use.

Unilever, which has backed funds managed by Circulate and New York-based Closed Loop Partners, aims to cut in half the amount of virgin plastic it uses by 2025 and plans to collect and process more plastic packaging than it sells. Coca-Cola, also a backer of Circulate’s Ocean fund, aims to make all of its global packaging recyclable by 2025 and to use at least 50% of recycled packaging material by 2030, among other goals.

Excerpt from Laura Kreutzer, Growth Firms See Plastic Waste as an Investment Opportunity, WSJ, June 23, 2021
 

Save Time and Money but Destroy Soil and Oceans

The images of swaths of garbage floating on the oceans’ surface have become a rallying call to address plastic pollution, but there is more to this challenge than meets the eye. While plastics and microplastics – items smaller than 5 mm – accumulate and impact marine environments, much of the problem is rooted in land contamination. Land-based plastic pollution, which often feeds into the oceans, is estimated to be at least four times higher than what is in the oceans, according to a study published in Global Change Biology. 

“Soil is the main source of microplastics reaching oceans through soil erosion and surface runoff,”  Plastics settle in soil through disposal in landfills, as well as through the use of plastic-sheets in agriculture or application of microplastic contaminated compost. “Direct disposal of plastics to ocean is relatively less pronounced compared to the transfer of microplastics from land. Microplastics, lighter than soil particles, such as sand, silt and clay, are easily lost to waterways,”…

“We contribute to plastic pollution through indiscriminate disposal of plastics in landfills and use of microbeads in cosmetics and microfibers in textiles. There are efforts to produce biodegradable plastics, which may provide some solution to plastic pollution, but bioplastic may not be the silver bullet to manage plastic pollution.” Commonly used biodegradable bioplastics “retain their mechanical integrity under natural conditions, potentially causing physical harm if they are ingested by marine or terrestrial animals.” “The fate of biodegradable bioplastics in natural and engineered environments could be potentially problematic. Methane is a product of biodegradation in anaerobic environments in landfills.” These bioplastics, furthermore, require high temperatures, controlled aeration and humidity to degrade completely.

Due to their small size, microplastics, especially nanoplastics resulting from the degradation of microplastic, can enter organisms’ internal organs, where they could potentially transfer contaminants attached to them. These can include persistent organic pollutants, like polychlorinated biphenyls (PCBs), as well as trace metals like mercury and lead. The plastics and pollutants that accumulate on or in them enter the food chain and can eventually be transferred to humans, causing growing food safety concerns.

The Joint FAO/IAEA Centre’s laboratories are equipped to research the presence of microplastics in food. “Techniques such as energy dispersive X-ray spectroscopy and infrared and Raman spectroscopy can be applied to screen for plastics in foods, enabling risk assessment and management,” said Andrew Cannavan, Head of the Joint Centre’s Food and Environmental Protection Section. 

Excerpt from Joanne Liou Out of Sight but not out of Mind: IAEA and FAO Launch R&D to Identify Sources, Impacts of Microplastic Pollution in Soil, IAEA Press Release, July 2, 2021

The Plastics Revolution: A Century Later

Businesses pay a fee to Tontoton,  a company established in 2019,  for every ton of plastic that they generate. Tontoton then uses the money to employ scavengers, who retrieve an equal weight of plastic garbage in Vietnam — the world’s No. 4 source of ocean debris…Tontoton said it has the only such program in Vietnam, while Plastic Bank runs a similar one in Indonesia and the Philippines, and the Plastic Collective covers Malaysia, Thailand, and Cambodia…Tontoton targets the worst ocean-bound rubbish, called orphan plastic because it cannot be recycled. Trash pickers find the single-use plastic along the cyan waters hugging Vietnam’s Phu Quoc and Hon Son islands. Their goal is to collect 5,000 tons a year and send it to INSEE, part of Siam City Cement, to be burned for energy….

These cleanup programs have sprung up globally as doubts emerge about recycling, which used to seem like a win-win idea because consumers could keep consuming and the environment could stay pristine. But instead, for decades, the public believed its plastic was being recycled, only to find that 91% of it was not, according to a study in the peer-reviewed journal Science Advances, assessing all plastic from 1950-2015.

Vietnam is a focus of cleanup campaigns because it’s among the top five countries sending litter to sea, along with China, Indonesia, the Philippines, and Thailand…These Asian countries earned this marker because they import so much waste for processing from the rest of the world.

Tontoton says clients sign a letter committing to multiple strategies beyond offsets, including plastic substitutes and reduction. The company helps them offset or “neutralize” plastic already used, but this isn’t a “getaway car” to escape broader responsibility. “Plastic neutralization cannot solve the problem by itself.”

Excerpt from LIEN HOANG, Vietnam tests waters for plastic credits to fight marine pollution, April 15, 2021

How the Global Trade in Plastics Spills Over the Oceans

Low-value or “residual” plastics – those left over after more valuable plastic is recovered for recycling – are most likely to end up as pollution. So how does this happen? In Southeast Asia, often only registered recyclers are allowed to import plastic waste. But due to high volumes, registered recyclers typically on-sell plastic bales to informal processors…When plastic types were considered low value, informal processors frequently dumped them at uncontrolled landfills or into waterways.

Plastics stockpiled outdoors can be blown into the environment, including the ocean. Burning the plastic releases toxic smoke, causing harm to human health and the environment. When informal processing facilities wash plastics, small pieces end up in wastewater, which is discharged directly into waterways, and ultimately, the ocean.

The price of many recycled plastics has crashed in recent years due to oversupply, import restrictions and falling oil prices, (amplified by the COVID-19 pandemic). However clean bales of (polyethylene terephthalate) PET and (high-density polyethylene) HDPE are still in demand. In Australia, material recovery facilities currently sort PET and HDPE into separate bales. But small contaminants of other materials (such as caps and plastic labels) remain, making it harder to recycle into high quality new products. Before the price of many recycled plastics dropped, Australia baled and traded all other resin types together as “mixed plastics”. But the price for mixed plastics has fallen to zero and they’re now largely stockpiled or landfilled in Australia.

Excerpts from Monique Retamal et al., Why Your Recycled Plastic May End up in the Ocean, the Maritime Executive, Mar. 8, 2021

When Life Colonizes Plastic: the Deep Sea Wonder

The ocean deep, where pressure is high, light absent and nutrients scarce, is often seen as a desert. But, as with other deserts, it has oases. Hydrothermal vents, methane-gas seeps and whale corpses are hot spots for marine wildlife.  These natural loci of biodiversity are now being joined by unnatural ones made of plastic. Researchers obtained 33 objects from the deep sea in the South China Sea. Most were bags, bottles and food wrappers, but they picked up some derelict fishing ropes and traps as well…

These objects were teeming with life. When the researchers examined their finds in a laboratory, they found nearly 1,200 individual organisms representing 49 species of crustaceans, corals, echinoderms, flatworms, molluscs, polychaete worms and fungi. They also discovered evidence that some of these species were breeding. There were egg capsules from four different types of snail, and a cocoon from a flatworm known for parasitising crustaceans. This result suggests that accumulations of plastic are, indeed, benthic oases… As to why organisms colonise the objects in these accumulations, the short answer is, “because they are there”.

Excerpts from Marine Ecology: Deep-ocean plastic is a haven for life, Economist, Feb. 6, 2021

A Present for the Earth: Reducing Plastic Leakage

Approximately 8 million metric tonnes of plastic litter flow to the ocean annually, and only 9% of plastic waste ever produced has been recycled….Another major issue relates to microplastics – those plastics that are smaller than 5 millimeters, and that pose increasing environmental, economic and health hazards… Discarded plastics break down into these smaller particles through natural weathering processes. Microplastics can enter water bodies through different pathways, including atmospheric deposition, run-off from land, roads and through municipal wastewater.

A review of technical solutions from source to sea explores a set of innovative tech solutions. Among these potential technologies include:

  • Introducing debris-cleanup boats, debris sweepers and sea-bins to remove plastics and other wastes carried into water bodies;
  • Protecting large bodies of water by introducing wetlands along coastlines;
  • Secondary and tertiary wastewater treatment which relies on membrane filtration to prevent microplastics entering rivers and lakes;
  • Advanced coagulation technology to make water contaminated with microplastics drinkable;
  • Promoting sustainable waste management practices to reduce plastic leakage.

A key principle of this work is preventing untreated wastewater, which is often packed with plastics and microplastics, from entering the environment in the first place.  The wastewater coming from urban residential, industrial and commercial settings is full of contaminants including plastics, microplastics and other debris…

Water pollution by plastics and microplastics: A review of technical solutions from source to sea, UNEP Press Release, Dec. 27, 2020

Air Pollution: the Microplastics We Breath

 Scientists measured microplastics — tiny particles and fibers of plastic that can float in the air like dust — and found that over 1,000 tons a year are falling into wilderness areas and national parks in the western U.S.  Janice Brahney of Utah State University and her team identified samples of microplastics and other particulates collected over 14 months in 11 national parks and wilderness areas to create the study published in the journal Science, on June 12, 2020.  Pieces of plastic less than 5 mm in length, or microplastics, occur in the environment as a consequence of plastic pollution…

The presence of microplastics in oceans and water supplies has been a matter of concern for some time, but the impact of airborne microplastics is a relatively new area of study. Though microplastics are found nearly everywhere on Earth, the sources and processes behind their ubiquitous distribution, or the “global plastic cycle,” remain vaguely understood.  Initially overlooked, recent studies have suggested that long-range atmospheric transport plays an important role in carrying microplastic pollution vast distances and to remote locations

Examination of weekly wet and monthly dry samples from 11 sites allowed the authors to estimate that more than 1,000 tons of microplastics are deposited onto protected lands in the western U.S. each year, equivalent to more than 123 million plastic water bottles.

The ubiquity of microplastics in the atmosphere has unknown consequences for humans and animals, but the research team observed sizes of particles that were within the ranges that accumulate in lung tissue. Moreover, the accumulation of plastic in the wilderness areas and national parks could well influence the ecosystems in complicated ways.

Excerpts, VICTORIA PRIESKOP, Scientists Find Tons of Microplastics Polluting National Parks, Courthouse News Service, June 11, 2020

Can’t Eat This! MicroPlastics Carrying Bacteria

The hard surface of waterborne plastic provides an ideal environment for the formation of biofilm by opportunistic microbial colonisers, and could facilitate a novel means of dispersal for microorganisms across coastal and marine environments. Biofilms that colonise the so-called ‘plastisphere’ could also be a reservoir for faecal indicator organisms (FIOs), such as Escherichia coli, or pathogenic bacteria such as species of Vibrio.

Nurdles on bathing beach

A study published in March 2019 looks into five public bathing beaches and quantifies their colonisation by E. coli and Vibrio spp. Nurdles [i.e., microplastics] were heterogeneously distributed along the high tide mark at all five beaches, and each beach contained nurdles that were colonised by E. coli and Vibrio spp. Knowledge of E. coli colonisation and persistence on nurdles should now be used to inform coastal managers about the additional risks associated with plastic debris.

Abastract from Colonisation of plastic pellets (nurdles) by E. coli at public bathing beaches