Plastic particles affect geometry? Human knowledge is still insufficient
Today's viewpoint
Our reporter Zhang Mengran
Plastic particles are entering the human body.
The CNN report shows that the world produces more than 330 million tons of plastic each year, and this number is expected to triple by 2050.
When they enter the ocean, they will be eaten by filter feeders and stay in them, passing through the food chain layer by layer.
But this does not seem to be the most terrifying.
The key problem is that we still do not understand the relevant health risks so far, and it is difficult to assess the harm of intake to humans.
What's more, fragile babies seem to be suffering the potential effects of plastic particles entering the body.
Previous research: Take one credit card a week?
In mid-2019, Newcastle University in Australia was commissioned by the World Wide Fund for Nature to estimate the global per capita plastic intake after combining 52 existing research data. The results warn people: the global per capita intake is about 2000 per week. The plastic particles weigh 5 grams of plastic, which is roughly equivalent to the weight of a credit card.
This study believes that there are plastic particles in countless daily foods and beverages, such as water, beverages, seafood and salt. Among them, the largest source of plastic intake should be drinking water. Ordinary people only drink bottled or tap water every week. It is possible to ingest as many as 1,769 plastic particles.
The report also pointed out that a very important source of plastic particles with a diameter of less than 5 mm are man-made clothes fibers, tiny beads in toothpaste, and slightly larger plastic fragments.
When these plastic particles-containing objects are randomly discarded and exposed to the natural environment, they will gradually decompose and become smaller and smaller in size, merge into rivers, lakes and seas to be swallowed by fish and other marine animals, and finally enter the food chain and enter the human body. .
After birth: or exposed to millions of plastic particles every day
Among non-fiber plastics, the annual output of polypropylene accounts for 20% of the total output and is the most widely used plastic in food preparation.
However, little is known about the release of plastic particles from such containers.
On the 19th, a human health report published in the British "Nature Food" magazine stated that researchers have recently discovered that when using a polypropylene-containing baby bottle to prepare standard formula milk, the bottle may release plastic particles. The result will directly affect the most vulnerable human beings in the early stages-babies.
Under the conditions of sterilization and formula milk powder brewing recommended by the World Health Organization, the research team at Trinity College in Ireland tested the release of plastic particles in 10 baby bottles. These bottles represent most of the bottles in the global online market.
They are either made of polypropylene or contain polypropylene-based accessories.
The research team found that the amount of plastic particles released from each bottle is between 1.3 million and 16.2 million particles.
These bottles continued to release microplastics during the 21-day test period, and the amount of microplastics released varies with water temperature and other factors.
Using these data, the Irish research team established a potential global model of human initial exposure to plastic particles.
They estimate that during the first 12 months of life, babies fed with polypropylene bottles will be exposed to 1.6 million plastic particles a day on average.
The data is amazing! But the impact is still unclear
This research result emphasizes the necessity of further research on the impact of plastic particles on human health. However, people's understanding of this point is still insufficient.
The researchers pointed out that the exposure patterns in different regions are actually different: Africa and Asia have the lowest potential exposures, while Oceania, North America and Europe have the highest potential exposures.
They concluded that the content of plastic particles that babies are exposed to may be higher than previously thought, and more research is needed to understand how plastic products that come into contact with food release plastic particles during daily use.
Richard Lampeter, a professor at the British National Oceanography Centre, has previously stated that it is difficult to assess the impact of intake without understanding the relevant health risks.
Because of the large uncertainties in plastic hazards so far, its potential impact urgently needs further study.
Scientist Philip Schwaber wrote in an opinion article: The degree of exposure to microplastics proposed in this new study is shocking, but the actual impact on infant health needs further investigation, because for people at this stage, The impact of microplastics and nanoplastics on human health is still unclear.