Question

1 Plastics are everywhere in our daily lives, from the bottles we drink out of to the clothes we wear. But as useful as they are, there is a downside: plastic pollution. As plastics break down over time, they turn into tiny particles. At first, these are microplastics, which are small enough to be just about the size of a sesame seed or even smaller. But they do not stop there; they can break down further into nanoplastics, which are so tiny that they are invisible to the naked eye. These minuscule particles can enter our body’s cells and tissues, which raises concerns about their impact on our health.

2 Scientists have discovered these tiny plastic particles in various human body parts, including blood, lungs, gut, and even in organs involved in reproduction. But the big question is: what are they doing to our health? Scientists are still determining. Nanoplastics are so small that they are challenging to detect and study, which makes understanding their effects complicated.

Research Process
3 Doctors Wei Min and Beizhan Yan at Columbia University enhanced a high-tech imaging technique known as stimulated Raman scattering (SRS) microscopy to grasp this issue better. This method, which Dr. Min co-developed with support from the National Institutes of Health (NIH) about 15 years ago, allows researchers to see small molecules inside living cells. It uses two laser beams to make molecules give off a unique type of light, making them visible. One of the great things about SRS microscopy is that it does not require the molecules to be specially marked to find them, which is a significant advantage over other methods.

4 In their latest research, the team developed a new version of this technique to detect microplastics and nanoplastics as small as a single particle. They created a machine learning algorithm to identify seven common types of plastic.

Research Results
5 They tested their new method on bottled water from three well-known brands. The recently published study revealed that a single liter of bottled water could contain about 240,000 tiny plastic pieces. Astonishingly, about 90% of these were nanoplastics. This finding far exceeds the amount of plastic detected in earlier studies, which focused mainly on larger microplastics.


Using lasers, scientists could detect
hundreds of thousands of previously invisible
tiny plastic particles in bottled water.

6 The water samples contained particles from all seven types of plastics the team was looking for. The most common were polyamide (a type of nylon often used in water filters) and polyethylene terephthalate (PET), commonly used to make the bottles themselves. Other plastics found are also frequently used in water purification processes. Interestingly, the method also identified millions of additional particles that did not match any of the seven known plastic types, leaving their identity a mystery.

7 Dr. Yan highlighted the significance of this breakthrough, saying it opens a new window into a previously unseen world of plastics. This advancement is about both understanding our exposure to tiny plastics and also opening up a new field of study.

8 Looking to the future, the research team aims to apply their method to more types of environmental samples, like tap water, air samples, and biological tissues. They are also focusing on developing filters to reduce plastic pollution from everyday sources, such as laundry wastewater. Many fabrics contain plastics like nylon and PET, so reducing their release into the environment is important.

Potential Health Effects
9 The health implications of microplastics and nanoplastics are a major concern. When plastics break down into these tiny particles, they can be absorbed through our skin, eaten, or inhaled. In the digestive system, microplastics can cause blockages and irritation, potentially leading to swelling and a range of digestion issues, including pain, bloating, and changes in bowel habits. These particles can also carry dangerous chemicals, leading to symptoms like nausea and vomiting.

10 When inhaled, microplastics can cause less oxygen to enter into our lungs and airways, leading to respiratory problems like coughing, sneezing, and shortness of breath. This stress can also cause fatigue and dizziness due to lower oxygen levels in the blood. Damage to respiratory cells and an increased risk of diseases like chronic obstructive pulmonary disease are also concerns.

11 Microplastics can interfere with our hormone systems, potentially causing a wide range of disorders, including those affecting metabolism, development, and reproduction, such as infertility and birth defects. These particles can also carry harmful substances, impacting the endocrine and reproductive systems. In a striking example, microplastics were found in the uterine lining of pregnant women, suggesting their potential to affect unborn children.

12 The immune system is not impervious to the effects of microplastics either. Long-term exposure in animals has shown long-term swelling and changes in immune responses. Studies on human lung cells indicate that microplastics can activate our immune systems.

13 Microplastics and nanoplastics represent a significant health concern due to their ability to enter and affect various body systems. More research is needed to fully understand these impacts on our health. Thankfully, the advancements in detection and analysis methods are paving the way for a deeper understanding and better management of this modern environmental challenge.



Sources Consulted:
Contie, Vicki. “Plastic particles in bottled water.” National Institutes of Health. Web. Updated January 2024. Accessed February 2024. nih.gov/news-events/nih-research-matters/plastic-particles-bottled-water#:~:text=The%20researchers%20found%20that%2C%20on,mostly%20focused%20on%20larger%20microplastics.
Lee, Yongjin, Jaelim Cho, Jungwoo Sohn, and Changsoo Kim. “Health Effects of Microplastic Exposures: Current Issues and Perspectives in South Korea.” NIH National Library of Medicine. Web. Updated May 2023. Accessed February 2024. ncbi.nlm.nih.gov/pmc/articles/PMC10151227/#
Doubek, James. “Researchers find a massive number of plastic particles in bottled water.” NPR. Updated January 2024. Accessed February 2024. npr.org/2024/01/10/1223730333/bottled-water-plastic-microplastic-nanoplastic-study
Krajick, Kevin. “Bottled Water Can Contain Hundreds of Thousands of Previously Uncounted Tiny Plastic Bits, Study Finds.” State of the Planet. Updated January 2024. Accessed February 2024. news.climate.columbia.edu/2024/01/08/bottled-water-can-contain-hundreds-of-thousands-of-previously-uncounted-tiny-plastic-bits-study-finds/

Image Credits:
Qian, Naixin. “Nanoplastics in bottled water.” State of the Planet. In the public domain. news.climate.columbia.edu/2024/01/08/bottled-water-can-contain-hundreds-of-thousands-of-previously-uncounted-tiny-plastic-bits-study-finds/
“Health Effects of Microplastics Exposure.”National Institutes of Health. In the public domain. ncbi.nlm.nih.gov/pmc/articles/PMC10151227/#

Read the sentence from paragraph 5.

Astonishingly, about 90% of these were nanoplastics.

What can the reader infer from this statement?
Microplastics cause more pollution than nanoplastics.
Most of the pollution caused by plastics is difficult to detect.
There is less pollution from plastics than researchers believed.
The new method of testing for plastic pollution is more effective.

Answer 1

The correct inference from the statement "Astonishingly, about 90% of these were nanoplastics" is:

**Most of the pollution caused by plastics is difficult to detect.**

This inference is drawn from the fact that a large majority of the detected particles are nanoplastics, which are much smaller and harder to detect than larger microplastics, suggesting that significant amounts of plastic pollution are in the form of nanoplastics and may have gone unnoticed in previous studies.