The intake of microplastics in food affects the intestinal microbiota

A group of researchers from the CSIC has discovered that ingesting microplastics reduces the bacterial diversity of the colon microbiota, in addition to producing an alteration of the balance in the microorganisms present.

EHEC bacteria with high resistance to antibiotics. EFE Manfred Rohde

The study, published in the journal Scientific Reports, shows that ingesting PET microplastics (associated with the food chain) reduces the abundance of bacteria known for their positive effects on health and increases the presence of other microbial groups related to pathogenic activity.

“Given the possible chronic exposure to these particles through our diet, the results obtained suggest that their continued intake could alter the intestinal balance and, therefore, health,” explains Victoria Moreno, from the Food Sciences Research Institute (CIAL) of the CSIC.

The study, in which the Institute of Catalysis and Petrochemicals (ICP) and the Institute of Ceramics and Glass (ICV) of the CSIC have also participated, is the first that has evaluated the impact of the ingestion of microplastics in the digestive tract and the human gut microbiota.

Knowing what happens in our body and the consequences that these materials can cause us in the short, medium and long term is important since, according to the most recent calculations, on average, each person could ingest between 0.1 and 5 grams of microplastics each week through food and drink.

In addition, the study has shown for the first time that these microplastics can undergo biotransformations throughout the gastrointestinal tract and reach the colon in a structurally different way than the original.

“All these observed mechanisms and factors, which are just beginning to be studied, will contribute to finding out if microplastics can remain in the human body and potentially accumulate in some organs and tissues,” he concludes.

To carry out the research, the CSIC team has designed a protocol for simulating the ingestion and digestion of microplastics under physiological conditions, which can be extrapolated to the study of other types of plastic and particle sizes.

“Using the in vitro model of gastrointestinal digestion patented by the CSIC, we were able to house the human colonic microbiota during the intervention with microplastics,” explains Victoria Moreno.

This protocol, combined with the use of electron microscopy and spectroscopy, has made it possible to monitor changes in the structure and morphology of microplastics in the digestive tract.

Sanitary garbage from the pandemic also affects health

The figures for sanitary waste generated during the pandemic are exorbitant. Poorly managed waste also affects health, exposing health workers to potential needle stick injuries, burns and harmful microorganisms, while also impacting communities living near landfills and improper waste disposal sites due to to air pollution, poor water quality or disease-carrying pests

Medical personnel in protective suits treat patients at the Wuhan Fang Cang makeshift hospital in Wuhan, Hubei province, China, 17 February 2020 EFE/EPA/STRINGER CHINA OUT

This is stated by the World Health Organization (WHO), which estimates that most of the 87,000 tons of equipment sent by the UN to protect medical personnel have become waste.

In his analysis, he highlights that the accumulation of this sanitary waste places enormous pressure on sanitary waste management systems around the world.

It is estimated that most of this material has ended up as garbage.

To that must be added vaccines, tests, masks and other materials.

Outside the initiatives carried out by the UN, “the numbers are even more incomprehensible,” says this United Nations organization.

According to their newsletter, the WHO study was carried out based on the approximately 87,000 tons of personal protective equipment purchased between March 2020 and November 2021 and shipped to countries through a joint United Nations emergency initiative.

It is estimated that most of this material has ended up as sanitary waste.

The authors of the report revealed that the shipment of more than 140 million test kits could generate another 2,600 tons of non-infectious waste (mainly plastic) and 731,000 liters of chemical waste.

Y the provision of more than 8,000 million doses of vaccines would have produced an additional 144,000 tons of waste in the form of syringes, needles and safe deposit boxes.

The authors point out that these figures only provide an initial estimate of the magnitude of the problem and do not take into account none of the products purchased outside the UN initiative, nor the waste generated by the public, such as disposable medical masks.

Illustration by Maria Gonzalez

Sanitary garbage

Although, as Dr. michael ryan, executive director of the Organization’s Health Emergencies Programit is absolutely vital to provide healthcare workers with the right personal protective equipment, but at the same time, “it is also vital to ensure that it can be used safely without affecting the surrounding environment.”

To achieve this, the organization highlights the need for effective management systems that include guidance for health personnel on what to do when medical equipment and products have already been used.

However, the reality of waste recycling in hospital facilities is far from optimal.

Nowadays, 30% of sites are not equipped to handle existing loads of healthcare waste, let alone the additional amount generated by COVID-19. This figure rises to 60% in less developed countries.

for the la Director of Environment, Climate Change and Health of the Organization, María NeiraCovid “is forcing the world to recognize the gaps and neglected aspects” of healthcare waste and the way we produce, use and dispose of our healthcare resources, “from cradle to grave”,

In this sense, Neira sees the need to carry out a significant change at all levels in the way we manage the flow of health care waste both globally and “up to the hospital floors”.

In his opinion, this transformation is “a basic requirement of climate-smart health care systems, to which many countries committed at the recent United Nations Climate Change Conference and, of course, of a healthy recovery from COVID-19 and preparation for other health emergencies in the future.”

Some recommendations

Among the recommendations of the report of the who contained in the aforementioned bulletin include the use of:

• Ecological packaging and transport
• Safe and reusable personal protective equipment (for example, medical gloves and masks)
• Recyclable or biodegradable materials

It also advises investing:

• In waste treatment technologies that do not require incineration
• In reverse logistics that support centralized treatment and investments in the recycling sector to ensure that materials, such as plastics, can have a second life