Daily Prelims Notes 5 February 2025

February 5, 2025
Posted by: OptimizeIAS Team
Category: DPN

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Daily Prelims Notes

5 February 2025

Table Of Contents

1. Discovery of Nearby Black Holes: Gaia’s Breakthrough Observations

Sub : Sci

Sec: Space sector

Why in News

Astronomers have discovered a massive black hole, Gaia BH3, relatively close to Earth. It is the largest known stellar-mass black hole in the Milky Way and was identified using data from the European Space Agency’s Gaia telescope. This discovery enhances our understanding of black holes and their formation.

About Black Holes:

Black holes are regions in space where gravity is so intense that nothing, not even light, can escape.
They are usually detected through their gravitational influence on nearby stars or through the X-ray emissions produced when matter falls into them.
However, some black holes remain ‘silent,’ with no X-ray emissions, making them difficult to detect.
Identifying Black Holes:
- Orbital Motion Analysis: When a visible star orbits a black hole, it appears to be moving around empty space.
- Doppler Effect Observations: Ground-based telescopes detect shifts in the star’s light spectrum, revealing changes in velocity.
- Mass Estimation: By analysing the star’s orbit using Kepler’s third law, astronomers infer the mass of the unseen object.
Formation: Black holes form when massive stars collapse at the end of their life cycle. This can happen through:
Supernova Explosions: Some high-mass stars explode, leaving behind black holes.
Direct Collapse: In some cases, stars collapse into black holes without an explosion.
Neutron stars, which form from less massive stars, have a maximum limit of around three solar masses. If an unseen companion exceeds this threshold, it must be a black hole.

About Gaia Telescope:

Launched by the European Space Agency (ESA) in 2013, Gaia is a space observatory designed to chart a three-dimensional map of the Milky Way.
Measure the positions, distances, and motions of approximately one billion stars with unprecedented precision. Study the composition and evolution of our galaxy.

Gaia’s Role in Black Hole Discovery:

The European Space Agency’s Gaia telescope has been monitoring billions of stars since 2013. By tracking their motion, Gaia helps identify anomalies indicating the presence of invisible massive objects like black holes.
The latest discovery, Gaia BH3, adds to the previous findings of Gaia BH1 and Gaia BH2, reinforcing the telescope’s crucial role in uncovering hidden black holes.

Gaia’s First Black Hole Discovery: Gaia BH1

Location: 1,560 light-years away, making it the closest known black hole to Earth.
A star was found orbiting an unseen massive object every six months. Data from the Large Sky Area Multi-object Fiber Spectroscopic Telescope (LAMOST) and Magellan Clay Telescope in Chile confirmed rapid motion.
Kepler’s third law calculations indicated a mass nine times that of the Sun, confirming it as a black hole.

The Second Discovery: Gaia BH2

Approximately nine solar masses. Identified through a similar technique of tracking a visible star’s motion around an invisible massive object.

The Largest Stellar-Mass Black Hole: Gaia BH3

Discovery in April 2024.
33 solar masses, surpassing the previous record-holder Cygnus X-1 by 12 solar masses. 2,000 light-years, located in the constellation Aquila.
A nearby yellow giant star orbits Gaia BH3 every 11.6 years at a distance comparable to that between the Sun and Uranus.
First black hole found in the outer Milky Way. It appears ‘passive,’ meaning it does not actively pull in matter or emit X-rays.

First Galactic Equivalent of LIGO-Detected Black Holes:

In 2015, LIGO and VIRGO detected gravitational waves from black holes of similar mass merging in distant galaxies (1-2 billion light-years away). Gaia BH3 provides a local counterpart for in-depth study.

Kepler’s Laws of Planetary Motion:

First Law (Law of Ellipses): Planets orbit the Sun in elliptical paths, with the Sun located at one focus of the ellipse.
Second Law (Law of Equal Areas): A line connecting a planet to the Sun sweeps out equal areas during equal intervals of time, indicating that planets move faster when closer to the Sun and slower when farther away.
Third Law (Law of Harmonies): The square of a planet’s orbital period is proportional to the cube of the semi-major axis of its orbit, establishing a relationship between the time a planet takes to orbit the Sun and its average distance from the Sun.

LIGO (Laser Interferometer Gravitational-Wave Observatory):

Detect gravitational waves—ripples in spacetime caused by massive cosmic events like merging black holes or neutron stars.

Consists of two facilities in the United States, located in Hanford, Washington, and Livingston, Louisiana.
In 2015, LIGO made the first direct detection of gravitational waves, confirming a major prediction of Einstein’s general theory of relativity.

Virgo Detector:

A large interferometer located near Pisa, Italy, designed to detect gravitational waves.
Works in conjunction with LIGO and KAGRA to form a global network of gravitational wave observatories.
Participated in the joint detection of gravitational waves from merging neutron stars and black holes, enhancing the ability to localize and study these cosmic events.

2. Monitoring Asteroid 2024 YR4

Sub : Sci

Sec: Space sector

Why in News

The United Nations’ planetary defence organizations are closely tracking an asteroid, designated 2024 YR4, which has a small probability of impacting Earth on December 22, 2032. While current estimates suggest a 98.7% chance that the asteroid will pass safely, global space agencies are actively monitoring its trajectory.

Key Points:

Detected on December, 2024.
Size Estimate: Between 40m and 90m in diameter.
Impact Probability: Currently estimated at 1.3%.
Potential Damage: Comparable to the energy of a nuclear explosion, significant if it impacts a populated area.
Current Torino Scale Rating: Level 3 out of 10, indicating a close encounter that warrants further monitoring.
In 2004, asteroid Apophis was initially assessed to have a 2.7% chance of impacting Earth in 2029. However, subsequent observations ruled out the possibility of collision.

UN-Endorsed Asteroid Reaction Groups:

International Asteroid Warning Network (IAWN) – Led by NASA, responsible for tracking and assessing asteroid threats.
Space Mission Planning Advisory Group (SMPAG) – Chaired by the European Space Agency (ESA), responsible for coordinating international response measures.

Possible Mitigation Strategies:

If 2024 YR4 maintains a risk above 1%, SMPAG may recommend intervention strategies, including:
Kinetic Impactor Mission: Similar to NASA’s DART (Double Asteroid Redirection Test) Mission (2022), which successfully altered an asteroid’s trajectory by colliding a spacecraft into it.
Continuous Observation: Ground and space telescopes will keep tracking YR4’s movement to refine calculations and assess potential risks.

Torino Impact Hazard Scale:

A tool for categorizing potential Earth impact events by near-Earth objects (NEOs) like asteroids and comets.
Established by the International Astronomical Union (IAU) in 1999 to aid public communication regarding asteroid impact hazards.
Scale Range: Integer values from 0 to 10, each with associated colour coding.
- 0: No risk; the likelihood of a collision is zero or negligible.
- 1: Normal; a routine discovery with a very low chance of collision.
- 2-4: Meriting attention; a close encounter with a possible threat that warrants monitoring.
- 5-7: Threatening; a significant threat of collision requiring action.
- 8-10: Certain collisions; a collision is certain, with varying levels of destruction based on the object’s size.

NASA’s Double Asteroid Redirection Test (DART) Mission:

To test a method of asteroid deflection by altering an asteroid’s motion through kinetic impact.
Target: Dimorphos, a moonlet of the asteroid Didymos.
Method: A spacecraft was intentionally crashed into Dimorphos to change its orbit.
The impact successfully altered Dimorphos’ orbit around Didymos by 32 minutes, demonstrating the feasibility of kinetic impact as a planetary defense strategy.

3. Building Blocks of Life Identified in Samples from Asteroid Bennu

Subject: Science

Section: Space Technology

Why in News?

NASA’s latest analysis of samples from asteroid Bennu has revealed vital chemical compounds necessary for life, reinforcing the theory that asteroids may have contributed to delivering these essential building blocks to early Earth.

Background on OSIRIS-REx Mission

NASA’s OSIRIS-REx spacecraft was launched to collect samples from asteroid Bennu, a rocky remnant from a larger celestial body.
Bennu formed 4.5 billion years ago, near the dawn of the solar system.
The spacecraft collected samples in 2020 and returned them to Earth in 2023, landing in Utah.

Scientific Significance of Bennu Samples

Analysis of Bennu’s samples revealed chemical building blocks of life.
Findings support the theory that space rocks may have seeded early Earth with ingredients necessary for life.

Key Discoveries in Bennu Samples

Two studies (published on January 29, in Nature Astronomy & Nature) found:
- Diverse organic compounds, including key molecules needed for life.
- Presence of amino acids (40 types), crucial for protein formation.
- Discovery of DNA and RNA nucleobases, supporting theories of life’s extraterrestrial origins.

Importance of Findings

Suggests that chemical building blocks of life are widespread in space.
Increases likelihood that life could have emerged elsewhere in the solar system.
Supports the hypothesis that early Earth received these compounds via meteorites or asteroids.

Composition & Origin of Bennu

Bennu is a carbon-rich asteroid, containing organic molecules found in other meteorites.
Unlike meteorites, Bennu’s samples were not contaminated by terrestrial sources, making them valuable for study.
Bennu’s parent body (asteroid) formed around 100 km in diameter and likely existed 12 billion years ago before breaking apart.

Implications for Astrobiology

Supports the theory that life’s building blocks may have arrived from space.
Reinforces the idea that organic material was present before Earth fully formed.
The essential components of life are organic compounds necessary for biological functions.
All living organisms, including human cells, are composed of four primary biomolecule classes: proteins, carbohydrates, lipids, and nucleic acids.

What Are Asteroids?

Asteroids are ancient, rocky celestial objects that orbit the Sun, primarily concentrated in the asteroid belt between Mars and Jupiter. These remnants from the early solar system, formed around 4.6 billion years ago, provide valuable insights into planetary formation and the origins of cosmic materials. While the majority reside within the asteroid belt, some asteroids follow orbits that extend beyond this region, occasionally crossing paths with Earth’s orbit or venturing into the outer solar system.

Asteroid Bennu:

Bennu is a carbon-rich asteroid with an approximate width of one-third of a mile. It approaches Earth every six years.
Scientists believe Bennu originated from a much larger carbon-rich asteroid, breaking away between 700 million and 2 billion years ago. It likely formed in the main asteroid belt before drifting closer to Earth.

4. Why the tax Cuts are a One-Way Gamble

Sub : Eco

Sec: Fiscal Policy

Context: Union Budget & recent Tax Cuts

The latest Union Budget has introduced significant income tax cuts, largely benefiting the middle class (2-3% of the population).
Key changes:
- Tax-free income limit raised from ₹7 lakh to ₹12 lakh.
- Exemption limit raised for high earners (₹12L+) from ₹3 lakh to ₹4 lakh.
- Marginal tax rates reduced across slabs.
- Estimated revenue loss: ₹1 lakh crore (~8% of direct tax collections).

Two (2) Scenarios and their implications

Assumption by Government: Higher Income Growth Will Cover the Shortfall

Despite reducing tax rates by 8%, the Budget projects a 14% increase in direct tax collections.
To achieve this, incomes need to grow by 24%, which is over twice the nominal GDP growth (10.1%).
Possible ways:
- Rapid rise in the number of high-income taxpayers.
- Higher tax buoyancy, meaning an increase in tax collections despite lower rates.

The Risk: What If Incomes don’t grow as expected?

Worst-case scenario: If tax revenue falls short, government spending will have to be cut.
Since under Fiscal Responsibility and Budget Management (FRBM) Act restricts government spending beyond tax revenue, making fiscal policy pro-cyclical (reinforcing economic cycles) rather than counter-cyclical (stabilizing them).
Budget Deficit Targets:
- 2024 Revised Estimate: 4.8%
- 2025 Budget Estimate: 4.4%
A lower deficit target means less flexibility to increase spending during economic slowdowns.

Will this strategy work?

If the gamble works: Higher income growth → more tax collections → fiscal stability.
If it fails: Lower revenues → budget cuts → economic slowdown → further revenue loss.
Criticism: Relying solely on tax cuts to drive economic recovery is risky, especially when corporate investment remains weak.

Risk and Concerns

Past budget trends show that when tax revenues fall, the government reduces spending across key sectors.
Even flagship schemes linked to the Prime Minister saw budget cuts in the Revised Estimates for 2024.
The most affected: Welfare programs for the poor and disadvantaged.

Fiscal Consolidation or Contraction?

The government is prioritizing deficit reduction over economic stimulus.
Key concern: If 4.8% deficit couldn’t boost growth, how will 4.4% do so?
In a slowdown, economies need stimulus (exports, corporate investment, or government spending).
With exports weak and corporate investment uncertain, the government is banking on tax cuts alone to drive growth.

K-shaped growth

K-shaped growth describes an uneven economic recovery, often observed after a recession or a major economic disruption.
In a K-shaped recovery, some sectors or groups of people experience a strong rebound, moving upwards like the upper arm of the “K”. Meanwhile, other sectors or groups continue to struggle and decline, resembling the lower arm of the “K”.
This type of recovery creates a widening gap between the winners and losers in the economy.
Examples of K-shaped growth: During the COVID-19 pandemic, Technology companies and certain sectors thrived, while industries like tourism, hospitality, and small businesses struggled.

5. How beggar-Thy-Neighbour Policies a threat to Global Trade

Sub : Eco

Sec: External policy

Why in News?

The term “Beggar-Thy-Neighbour” has gained renewed relevance amid growing trade tensions and currency devaluations, particularly between major economies like U.S. and China.

Context:

Beggar-thy-neighbour policies refer to protectionist economic measures that benefit one country’s economy at the expense of others.
Such policies can include high tariffs, strict import quotas, and currency devaluations.
Critics argue that global trade wars, often fueled by these policies, can cripple international commerce, leading to economic downturns like the Great Depression.

Economic Mechanism

These policies are adopted to protect domestic industries but often result in economic retaliation from other countries.
The most common examples include:
- Trade Barriers: Imposing high tariffs and import quotas on foreign goods.
- Currency Wars: Central banks depreciate domestic currencies to boost exports and discourage imports.

Historical Origins

The term was first introduced by Scottish economist Adam Smith in 1776 in his book The Wealth of Nations.
Smith criticized mercantilist policies, arguing that free trade benefits all nations, while protectionism only leads to economic decline.

Supporters’ Arguments

Protecting Domestic Industries & Jobs:
- Some industries require government protection for national security or to survive in their nascent stage.
Boosting Exports via Currency Depreciation:
- A weaker domestic currency makes exports cheaper and more competitive globally.
- Higher exports & lower imports can lead to a trade surplus, benefiting the domestic economy.

Critics’ Concerns & Global Impact

Risk of Trade Wars & Economic Retaliation
Tit-for-tat tariffs and devaluations often lead to a cycle of retaliation, reducing global trade.
The interwar period (1918-1939) saw widespread trade barriers and currency devaluations, worsening the Great Depression.
Recent Examples:
- China & Japan have faced accusations of currency devaluation to maintain trade surpluses.
- U.S.-China Trade War (2018-2020) saw heavy tariffs imposed by both countries, impacting global markets.

Impact on Consumers

Higher tariffs may protect domestic producers but increase prices for consumers.

Example: U.S. tariffs on Chinese goods helped American manufacturers but raised costs for U.S. consumers.

Currency devaluations can reduce purchasing power, making domestic goods more expensive.

Alternative Approach: Unilateral Free Trade

Some economists argue that retaliatory tariffs hurt the imposing country’s consumers.

Example: If the U.S. imposes tariffs on Chinese goods, China retaliating with tariffs on U.S. goods will further harm its own consumers.

Free trade proponents believe that avoiding retaliatory tariffs can allow one country to benefit from another’s protectionist mistakes.

6. Home Ministry’s Directive on Preventing Misuse of the State Emblem of India

Sub: Polity

Sec: Constitution

Context: – The Union Home Ministry has asked State governments to prevent the misuse and improper depiction of the State Emblem of India.

The Ministry emphasized that the Lion Capital logo is incomplete without the motto “Satyameva Jayate” in Devanagari script.

Concerns Raised by the Ministry

Various government agencies using the State Emblem on their stationery, publications, seals, vehicles, buildings, and websites often omit the motto “Satyameva Jayate.”
The design is not in conformity with the Appendix I & II of the Schedule of the State Emblem of India (Prohibition of Improper Use) Act, 2005.
An incomplete display of the State Emblem is a violation of the Act.

Description of the State Emblem

The State Emblem is the official seal of the Government of India, adapted from the Sarnath Lion Capital of Ashoka.
It consists of:
- The profile of the Lion Capital showing three Lions mounted on the abacus.
- A Dharma Chakra in the Centre.
- A bull on the right and a galloping horse on the left.
- Outlines of Dharma Chakras on the extreme right and left.
- The motto ‘Satyameva Jayate’ written in Devanagari script below the profile of the Lion Capital.

Misuse by Unauthorized Individuals and Authorities

Various individuals and authorities not authorized to use the Emblem are displaying it on their stationery, vehicles, etc.
The use of the State Emblem of India is restricted to specific authorities and purposes, as per:
- The State Emblem of India (Prohibition of Improper Use) Act, 2005.
- The State Emblem of India (Regulation of Use) Rules, 2007.

Government’s Warning and Action

Strict action should be taken against:
- Officials responsible for the incomplete display of the State Emblem.
- Individuals and organizations using the State Emblem unauthorisedly.
- Punishment includes imprisonment up to 2 years, a fine up to ₹5,000, or both.
- Falsely claiming the right to use the emblem is also a punishable offense.

Government’s Authority

The Central Government has the power to make rules regarding the use, display, and restrictions on the emblem.
The government can seize or confiscate unauthorized emblem usage

7. Deport Foreigners, Do Not Detain Them for Eternity: Supreme Court

Sub: Polity

Sec: Constitution

Context: The Supreme Court on Tuesday (February 4, 2025) pulled up the Assam government for detaining indefinitely people declared as foreigners in detention camps.

Issue of Nationality Verification

The State’s affidavit stated that nationality verification forms were not sent to the Ministry of External Affairs as the addresses of detainees in their native country were not known.

Role of the Centre and Court’s Directives

The Court ordered the Centre to inform in what manner the cases of persons whose nationality is not known were being dealt with.
The Union government was directed to place on record the details of declared foreigners and the number of persons who had so far been deported.
The Court directed the State to file a proper affidavit reporting compliance.

Challenges in Deportation Process

Attempts are being made to figure out if Bangladesh will take these people out. Bangladesh is refusing.
India says they are not Indians. Bangladesh says they are not Bangladeshis. They have become stateless. They are in detention for over 10 years.

Monitoring of Detention Facilities

The Court directed the Assam State Legal Services Authority to conduct surprise visits at the Matia transit camp for foreigners.
The purpose of these visits is to check the facility’s hygiene and food quality.
Article 21 of the Indian Constitution grants the right to life and personal liberty to all people, including foreigners.

About Foreigners Tribunals (FTs)

Foreigners Tribunals (FTs) are quasi-judicial bodies established under the Foreigners (Tribunals) Order, 1964, under Section 3 of the Foreigners Act, 1946.
They allow local authorities to refer individuals suspected of being foreigners for determination of their citizenship status.

Foreigners (Tribunals) Order (Amendment 2019):

Specifies the procedure for handling appeals against the National Register of Citizens (NRC) decisions.
Empowers district magistrates across India to set up tribunals.
While applicable nationwide, FTs currently function only in Assam.

Composition:

Each FT is headed by a member who is a judge, advocate, or civil servant with judicial experience.
Judges/Advocates are appointed as per government guidelines under the Foreigners Tribunal Act, 1941, and Foreigners Tribunal Order, 1964.

Functions & Powers:

FTs have powers of a civil court, including summoning individuals and examining documents.
Notices must be served within 10 days of receiving a reference.
Cases must be disposed of within 60 days.
As per Section 9 of the Foreigners Act, 1946, the burden of proof lies on the individual to prove their Indian citizenship.
If unable to provide proof, individuals may be sent to a detention centre (transit camp) for deportation.

Appeal Process:

Review application can be filed within 30 days of the FT’s order.
Adverse decisions can be appealed in the High Court, followed by the Supreme Court if needed.

8. U.S. sends back 200 Indians on military plane

Sub : IR

Sec :India and world

Context:

Ahead of Prime Minister Narendra Modi’s upcoming visit to the U.S., the Trump administration has begun deporting illegal Indian immigrants, with a military aircraft carrying around 200 Indian nationals departing the U.S. for India.
The deportation follows a conversation between Modi and President Trump, where Trump emphasized India’s role in addressing illegal immigration.

Deportation Method:

The S. administration has been tightening immigration laws, with over 160,000 individuals deported since June 2024, including many from India.
While the deportation of Indian nationals is not new, the use of a military aircraft for this purpose represents a novel method.
Previously, large-frame charter flights were used for deportations, but this military air transport signifies an escalation in the execution of deportation policies.

India’s position:

India’s diplomatic relations with the U.S. regarding illegal immigration are cooperative. The Indian government has been in discussions with U.S. officials, particularly under the Trump administration, about the deportation of illegal immigrants.
India has confirmed its willingness to take back its citizens who are illegally staying abroad, provided their nationality is verified.
While India has agreed to repatriate its nationals, the country has also expressed concern over the broader issue of U.S. immigration policy, especially the tough stance adopted by the Trump administration.

9. El Salvador to accept deportees from U.S. of any nationality

Sub : IR

Sec :Places in news

Context:

U.S. Secretary of State Marco Rubio reached an agreement with El Salvador’s President Nayib Bukele concerning the deportation of foreign nationals, including violent criminals currently imprisoned in the United States.

Details of the Agreement:

Under this agreement, El Salvador would accept deportees of any nationality, even those including violent criminals, who will be transferred to El Salvador’s prisons.
Only “convicted criminals” would be accepted into El Salvador’s prisons
El Salvador would charge the U.S. a relatively low fee in exchange for accepting these prisoners.
The revenue generated from this arrangement is expected to support El Salvador’s prison system, which has struggled with overcrowding and underfunding.

About El Salvador:

El Salvador is a country in Central America. It is bordered on the northeast by Honduras, on the northwest by Guatemala, and on the south by the Pacific Ocean.
El Salvador’s capital and largest city is San Salvador.
El Salvador has been under a state of emergency since March 2022, with violent gangs rampaging across the country.

10. Syria’s al-Sharaa, Turkey’s Erdogan talk Kurdish fighters, defence pacts

Sub : IR

Sec : Places in news

Context:

Turkish President Recep Tayyip Erdogan and Syria’s newly appointed interim President Ahmed al-Sharaa held discussions in Ankara, marking a significant diplomatic shift in relations between the two nations.
This meeting was al-Sharaa’s second international visit since assuming his new position, following a prior meeting with Saudi Arabia’s Crown Prince Mohammed bin Salman.
The two leaders discussed a potential new defence pact, which could include Turkey establishing additional military bases in Syria.

Details of the Discussion:

The leaders discussed deepened security ties, particularly concerning Kurdish fighters in northeastern Syria and the Islamic State of Iraq and the Levant (ISIL/ISIS).
Erdogan expressed Turkey’s readiness to support Syria’s fight against terrorism, including groups like ISIL (Daesh) and the Kurdistan Workers’ Party (PKK), which Turkey views as terrorist organizations.
The Turkish government has concerns over Syrian Kurdish groups, such as the People’s Defence Unit (YPG), which operates in the northeast of Syria and is a key component of the S. backed Syrian Democratic Forces (SDF).
Al-Sharaa rejected any form of Kurdish self-rule and called for the SDF to surrender their weapons, reflecting Syria’s desire for territorial unity.

Turkey-Syria tensions:

The border between the Syria and Turkey is 909 kilometres long, and runs from the Mediterranean Sea in the west to the tripoint with Iraq in the east.
One of the primary sources of tension between Turkey and Syria is the presence of Kurdish militant groups in Syria. The Kurdistan Workers’ Party (PKK), which has waged an insurgency against Turkey since the 1980s, is considered a terrorist organization by Turkey.
The Kurds, an ethnic minority group in Middle East are found in Turkey, Syria, Iraq, Iran, and Armenia, with their largest population residing in Turkey. The Kurds are demanding a separate Kurdish homeland, Kurdistan.
The Syrian Democratic Forces (SDF), a Kurdish-led militia primarily composed of the People’s Defence Units (YPG), became a key ally of the U.S. in the fight against ISIS.
However, Turkey views the YPG as an extension of the PKK and has raised concerns about their growing power in northern Syria, particularly near Turkey’s southern border.

11. The Promises and Problems of Using Bacteria Against Plastic

Sub : Env

Sec: Pollution

Introduction

Plastic waste crisis has driven biologists to find sustainable solutions using bacteria and enzymes for degradation.
Scientists and companies are researching, innovating, and commercializing these solutions.
Challenges include scalability, efficiency, and industry adoption.

Challenges in Plastic Waste

Plastic is hard to degrade and persists in the environment for centuries.
Since large-scale plastic production began 65 years ago, about 8.3 billion tonnes have been produced.
Only less than 10% has been recycled, while around 4.9 billion tonnes remain in the environment.

Microbial Solutions to Plastic Degradation

Enzyme-Based Approach

Scientists have engineered enzymes to break down PET (Polyethylene Terephthalate) plastic.
Kōhei Oda’s team discovered an enzyme in 2016, IsPETase, which breaks PET down slowly.
Advancements in enzyme engineering now allow 90% degradation of PET in just 17 hours into reusable monomers like terephthalic acid and ethylene glycol.
Challenges:
- Increasing speed and efficiency of enzyme degradation.
- Reducing costs for large-scale industrial applications.

Microbial Degradation Approach

Scientists are also working on microbial solutions where bacteria directly consume plastics.
Example: A bacterium named X-32 takes around 22 months to break down plastics into CO₂, water, and biomass.
Key Process:

Microbial attachment to plastic surfaces.
Microbes use plastic as a carbon source for energy.
Polymer breakdown through enzyme secretion.

Challenges:
- Slow degradation rate compared to enzyme-based methods.
- Needs optimization for industrial scalability.

The Biological Approach: Spore-Based Biodegradable Plastic

Researchers at Harvard and Wyss Institute have developed a bacteria-based thermoplastic.
Process:
- Heat-resistant bacterial spores (Bacillus subtilis) are embedded in plastic.
- Spores remain dormant in normal conditions but activate in composting environments.
- They reinforce plastic structure and eventually help degrade it.
Advantages:
- Enhances durability of plastic when in use.
- Degrades faster in composting conditions.
- Industry-friendly alternative.
Challenges:
- Regulatory approval concerns for consumer products.
- Scaling up spore purification for mass production.

Industry Adoption and Challenges

Companies and researchers working on making bacterial and enzymatic plastic degradation industrially viable.

Example:

Carbios (French company) developed a PET-digesting enzyme that breaks down plastic in 10 hours.
North Carolina’s biomaterial companies are testing thermoplastics with spores for biodegradability.
Scaling remains a major hurdle, as commercial production requires:
- Higher efficiency in degradation.
- Lower costs for enzyme purification.
- Industries willing to adopt the technology.

Conclusion

Bacteria and enzymes offer potential solutions to plastic waste.
Research advancements are promising, but scalability, efficiency, and industry adoption remain major challenges.
Future efforts should focus on enhancing enzymatic processes, developing microbial solutions, and ensuring commercial feasibility.