Category : Health and you
The unseen biological intruders
We often think of pollution as something visible and physically experiencing, for example the smog, air quality index, waste from industry, garbage and contaminated water. Yet, some of the most consequential exposures today are biologically silent and chemically persistent. Microplastics, along with plastic-associated compounds such as phthalates and bisphenols, have become deeply integrated into our daily exposure landscape.
What makes this combination particularly concerning is not merely their presence, but their interaction. Microplastics are not mere inert debris today. They act as carriers, binding, concentrating, and transporting endocrine-disrupting chemicals (EDCs) into biological systems. In simple terms, they act like “Delivery Vehicles,” carrying harmful chemicals into the body. You can also think of them as a “Trojan Horse,” quietly bringing these substances inside without us realizing it. This makes their effects stronger and longer-lasting than we would normally expect.
What do these chemicals do in our body?
Our body depends on hormones, which are the chemical messengers that control growth, metabolism, reproduction, and many other functions. Chemicals like phthalates and bisphenols can disturb this system. Instead of working normally, they:
- Act like fake hormones
- Block natural hormones
- Confuse the body’s signals
Even very small amounts can cause problems, especially during important stages like pregnancy, infancy, and childhood.
In early stages of life i.e., during pregnancy, in newborns, and in young children, the body is still developing and more sensitive to harmful substances. The systems that help remove toxins from the body are not yet fully developed. Because of this, these chemicals can stay in the body for longer and may have stronger effects than they would in adults.
Mechanistic insights: Where chemistry meets physiology
Taking Bisphenol A (BPA) as a representative example, its metabolism relies heavily on the conjugation system in the liver. In adults, this pathway facilitates rapid clearance. However, in fetuses and neonates, as discussed earlier the reduced enzymatic capacity leads to greater bioavailability of the active compound. By “mimicking” natural hormones, they can send wrong signals to the body and over the time, this may affect how organs develop and function.
The presence of microplastics shifts the entire exposure paradigm, because it is not just the dose that matters, but themetabolic context in which the dose is encountered. Because, when these microplastics are present, they may help these chemicals stay longer in the body or enter more easily, increasing their effects.
Clinical implications: Beyond theoretical toxicology
Reproductive health:
The reproductive system appears particularly sensitive to endocrine disruptors. In females, exposure has been associated with:
- Reduced fertility
- Irregular menstrual cycles
In males, the impact is often seen in:
- Impaired sperm synthesis
- Reduced sperm quality and motility
What is noteworthy is that many of these effects trace back to early-life exposures, long before clinical manifestations become apparent.
Metabolic reprogramming:
There is increasing recognition that these chemicals do not merely cause toxicity, but also they may reprogram our metabolic pathways. Chronic exposure has been linked with:
- Increase in the risk of obesity
- Affect blood sugar control
- Contribute to diabetes
This means lifestyle diseases may not be due to diet alone, but environmental-biochemical interaction also plays a vital role.
Brain development and behaviour:
The developing brain is another vulnerable target. Hormones help the brain grow and develop properly by guiding how brain cells move, connect, and communicate with each other. Even small disturbances in these signals can affect brain development and may lead to long-term effects. Associations have been observed with:
- Learning ability
- Behaviour
- Attention span
Some studies suggest links with conditions like ADHD and autism.
Where are these chemicals found in daily life?
These substances are extremely common in modern living. You may encounter them in:
Plastic food containers and water bottles
- Packaged and processed foods
- Plastic toys
- Cosmetics and personal care products (like lotions, perfumes)
- Detergents and cleaning agents
- Food packaging materials (wrappers, cling films)
- Electronic items with plastic coatings (mobile phones cover, laptops, chargers)
Because they are so widespread, exposure happens almost daily, often without us realizing it
Who is more vulnerable?
Some groups are more sensitive to these chemicals:
- Pregnant women → exposure can affect the developing baby
- Infants and children → their bodies are still growing
- Adolescents → hormonal changes make them more sensitive
- People with chronic conditions → may be more affected by added stress on the body
In these groups, even small exposures can have stronger and longer-lasting effects.
How can we reduce exposure?
While it is difficult to avoid these chemicals completely, however few simple steps can reduce exposure:
- Avoid heating food in plastic containers
- Use glass or steel instead of plastic whenever possible
- Reduce use of packaged and processed foods
- Choose toys and products labelled “phthalate-free” or “BPA-free”
- Avoid single-use plastics
- Wash fruits and vegetables properly
These small changes can make a meaningful difference over time.
Looking ahead: Where the science must go next?
Refining detection and measurement:
One of the major challenges lies in accurately quantifying exposure. Advances in analytical techniques, particularly High-Resolution Mass Spectrometry are enabling detection of these compounds at previously inaccessible levels.
However, what we need is not just detection, but:
- Correlation with clinical phenotypes
- Integration with omics-level data
- Longitudinal exposure mapping
Rethinking materials and policy:
The long-term solution lies upstream, in material science and regulation. Developing biodegradable alternatives and enforcing stricter controls on EDC usage are essential. Equally important is shifting public perception. These are not abstract environmental contaminants, but they are biologically active agents influencing human health in real time.
Take-home message
Microplastics and related chemicals may be invisible, but they are constantly present in our daily lives. Their effects are not immediate or dramatic, which makes them easy to ignore. However, over time, they can quietly build up in the body and start influencing our health in subtle ways.
These are not just environmental pollutants. We interact with them continuously at a biological level. Understanding and reducing exposure is important, as many modern health problems may be influenced not just by lifestyle or genetics, but also by these often-overlooked environmental factors.
By,
Dr.(Lt Col) Karthik Kanakoor
Assistant Professor
Deptartment of Biochemistry
JSS Medical College/JSSAHER, Mysuru
Email: karthikkanakoor@jssuni.edu.in