Warming Seas and Microplastics Are Harming Sardines—And Us

March 23, 2025 / activist360

Infographic showing how feeding behavior and temperature affect plastic fibre ingestion in European sardines (Sardina pilchardus). Sardines that use filter-feeding ingest more plastic fibres, expel them faster, and have a lower condition index compared to particulate-feeding sardines. Warmer temperatures (19°C) increase plastic fibre ingestion and speed up intestinal transit time.

Feeding behavior and warming seas influence plastic fibre ingestion in sardines. Sardines that filter-feed ingest significantly more plastic fibres than those that eat larger particles (particulate-feeding). Warmer water temperatures (19°C) lead to faster digestion but also more plastic consumption. Filter-feeding sardines show lower health scores, highlighting the combined stress of microplastic pollution and climate change. (Source: Rodriguez-Romeu et al., 2024)

Sardines may be small, but they play a big role in the ocean—and on our dinner plates. These little fish are a key food source for larger marine animals like dolphins and tuna, and millions of people around the world eat them, too. They’re also packed with nutrients and are considered one of the most sustainable seafood choices out there.

But sardines are in trouble. In the Mediterranean Sea, their population has dropped sharply in recent decades. And scientists are discovering that two major forces—warming ocean temperatures and plastic pollution—are teaming up to make life even harder for these essential fish.

What’s harming sardines may be a warning sign for us all.

The Hidden Threat: Plastic Fibres in the Ocean

Microplastics are tiny pieces of plastic that break down from larger items like bottles, bags, and packaging. But not all microplastics are the same. A specific type called plastic fibres is even more common in the ocean—and more likely to be eaten by fish.

Plastic fibres are tiny thread-like pieces that come from clothing, fishing gear, and other waste. They’re too small to see with the naked eye but can float in the water, where fish easily mistake them for food. In fact, up to 91% of microplastics in ocean water are fibres, making them the most common type of plastic pollution in the sea.

The Experiment: What Scientists Found

To better understand how sardines interact with plastic fibres, scientists designed a unique experiment. They took wild sardines and placed them in tanks that mimicked ocean conditions. The tanks contained a realistic amount of plastic fibres—five fibres per liter of water, similar to what’s found in polluted areas of the sea.

They fed the sardines in two different ways:

Particulate-feeding: Fish were given large food pellets, which they eat one by one.
Filter-feeding: Fish were given tiny particles, similar to how they naturally eat plankton by filtering water through their gills.

The scientists also tested two water temperatures:

16°C, which reflects current Mediterranean conditions.
19°C, which represents a possible future scenario as oceans warm due to climate change.

Startling Results: What Happened to the Sardines

The results were clear—and concerning.

Sardines that fed by filter-feeding accidentally ate about eight times more plastic fibres than those eating larger particles. On average:

Filter-feeders ingested 4.95 fibres per fish
Particulate-feeders ingested only 0.6 fibres per fish

Temperature also made a difference. At warmer temperatures (19°C):

Sardines expelled plastic fibres faster, likely due to faster digestion.
But they also ingested more plastic, probably because their metabolism increased and they needed more food.

Another discovery: Plastic fibres stayed in the sardines’ digestive system longer than real food. Half the food was gone in about 12–14 hours, but it took 23–25 hours to get rid of just half the plastic fibres.

The Health Impact on Sardines

Over the course of the experiment, filter-feeding sardines didn’t just eat more plastic—they also got weaker.

They lost more weight and had lower body condition scores compared to those eating larger particles.
Their stomachs were less full, which suggests they ate less food overall and didn’t get enough energy.

Interestingly, the plastic alone wasn’t what made them unhealthy. Instead, it was the combination of filter-feeding and warmer water that seemed to hurt them most. Warmer oceans can lead to smaller plankton, which makes filter-feeding more common—and that leads to more plastic being ingested.

Why This Matters for Climate and Human Health

The health of sardines isn’t just a fish problem—it’s an ocean problem and a human problem.

Here’s why this matters:

Warming oceans = smaller plankton
Smaller plankton = more filter-feeding by fish
More filter-feeding = more plastic consumed

If sardine populations continue to shrink:

Predators like tuna, dolphins, and seabirds could lose a key food source.
People who depend on sardines for protein or income may struggle.
Ocean ecosystems could become unbalanced.

These changes don’t happen in isolation. Climate change and plastic pollution often work together, creating stress that marine life—and people—may not be able to overcome.

What Can We Do?

The good news is that small changes on land can protect life in the sea. Here are a few steps anyone can take:

Choose clothes made from natural fibers (like cotton or wool). Washing synthetic clothes sheds plastic fibres into the water.
Reduce plastic packaging by using reusable bags, bottles, and containers.
Support ocean cleanup efforts and organizations that study microplastics.
Advocate for climate action, including clean energy and reduced carbon emissions, to help slow ocean warming.
Hold your local, state, and national elected officials accountable for taking climate action and protecting our water, air, and health.

A Call to Protect What Connects Us All

Sardines may not get much attention, but they’re part of a delicate chain that connects us all. When small creatures suffer, the effects can ripple through the food web—and onto our plates.

The choices we make on land ripple into the sea—and into our future.

By staying informed, reducing plastic use, and supporting climate action, we can help protect the ocean, our food systems, and the health of generations to come.

Source: Rodriguez-Romeu, O., Constenla, M., Soler-Membrives, A., Dutto, G., Saraux, C., & Schull, Q. (2024). Sardines in hot water: Unravelling plastic fibre ingestion and feeding behaviour effects. Environmental Pollution, 363, 125035. https://linkinghub.elsevier.com/retrieve/pii/S0269749124017500

Microplastics in Our Brains?!? What Scientists Have Discovered About Plastic Pollution and Human Health

February 9, 2025 / activist360

Comparison of microplastic accumulation in human organs—brain has 10x more than liver and kidney, visualized with sugar in glass jars.

Microplastic Concentrations in Human Organs: Brain samples contained 7–30 times higher MNP concentrations than liver or kidney tissues. Median MNP concentration in the brain (2024 samples): 4,917 µg/g (range: 4,026–5,608 µg/g). Median MNP concentration in the liver (2024 samples): 433 µg/g. Median MNP concentration in the kidney (2024 samples): 404 µg/g.

Why Should We Care?

Plastic pollution is everywhere. Scientists have found microplastics in our food, drinking water, and even the air we breathe. But a new study has revealed something even more alarming—microplastics are accumulating in human brains!

Researchers found that brain samples contained up to 30 times more microplastics than other organs, raising concerns about long-term health risks. Even more shocking, people with dementia had five times the amount of microplastics compared to those without the disease.

What does this mean for our health? Let’s break it down.

What Did Scientists Find?

A team of researchers studied liver, kidney, and brain samples from people who had passed away. Using advanced technology, they found:

All organs contained microplastics, but the brain had the highest levels—even more than the liver and kidneys, which naturally filter toxins.
The most common type of plastic found was polyethylene (PE)—used in plastic bags, food packaging, and containers.
The average microplastic concentration in the brain was 4,917 µg per gram of tissue—compared to 433 µg/g in the liver and 404 µg/g in the kidneys.

To put the quantity of microplastic concentration into perspective, imagine you’re filling three jars with sugar to represent the amount of microplastics in different organs:

The kidney jar gets a small teaspoon (404 µg/g).
The liver jar gets about the same—just over a teaspoon (433 µg/g).
But the brain jar? You dump in more than 10 times that amount—nearly half a cup (4,917 µg/g)!

Now picture that sugar as tiny plastic shards instead of something sweet. Your brain—one of the most protected organs in your body—is absorbing these particles at a dramatically higher rate than the liver or kidneys, which are designed to filter out waste.

While other organs process and remove toxins, the brain seems to be holding onto plastic, potentially for life. Scientists still don’t know exactly what that means for long-term health, but they do know the levels are rising quickly, and that’s a cause for concern.

This is the first time scientists have confirmed that microplastics are accumulating in the human brain—a place that should be well-protected from foreign substances.

Why Is This a Big Deal?

Plastic doesn’t belong in our bodies, let alone inside our brains! Scientists are especially worried because:

Microplastics in the brain may contribute to neurological diseases. In people diagnosed with dementia, microplastic levels were over 26,000 µg per gram of brain tissue—more than five times higher than in non-dementia cases. These tiny plastics were found inside blood vessel walls and immune cells, suggesting they might be affecting brain function.

Microplastics can bypass the brain’s defense system. The blood-brain barrier normally protects the brain from harmful substances. This study suggests nanoplastics (as small as 100–200 nanometers) may be slipping through, raising concerns about how they could impact brain health over time.

While scientists haven’t proven that microplastics cause diseases like dementia, the fact that they are accumulating in the brain demands more research.

How Do Microplastics Get into Our Bodies?

You may not realize it, but we consume and inhale plastic particles every day. Here’s how they might be reaching our brains:

Breathing in tiny plastic particles from dust, air pollution, and synthetic fabrics.
Eating plastic-contaminated food—studies have found microplastics in seafood, salt, fruits, and vegetables.
Drinking bottled water, which contains nearly double the amount of microplastics as tap water.
Absorption through the bloodstream—scientists believe that some nanoplastics are small enough to pass through protective barriers in our bodies.

Once inside, these plastics don’t just disappear. They may stay trapped in organs like the liver, kidneys, and brain for years.

Has This Problem Gotten Worse?

Yes—dramatically. Scientists compared brain samples from 2016 and 2024 and found that:

Microplastic levels in the brain have increased by nearly 50% in just 8 years.
Similar increases were found in the liver and kidney, suggesting we are all being exposed to more plastic than ever before.
Older brain samples (1997–2013) contained far fewer microplastics than recent ones, proving this is a rapidly growing problem.

With plastic production and pollution continuing to rise, scientists predict that microplastic exposure will only get worse unless major changes are made.

What Can We Do About It?

While the full health effects of microplastics are still unknown, reducing exposure is a smart move. Here’s how:

Use fewer plastics: Switch to reusable bags, glass or metal water bottles, and cloth grocery bags.
Filter your water: Some high-quality filters can remove microplastics from drinking water.
Limit processed foods: Fresh, whole foods are less likely to contain microplastics than packaged and processed foods.
Ventilate your home: Indoor air contains plastic particles from synthetic fabrics and household dust—keeping air clean can reduce inhalation.
Support policies to reduce plastic pollution: Push for laws that limit plastic waste and promote better recycling solutions.

Summing Up

Microplastics are inside our brains, and their levels are rising at an alarming rate. Scientists don’t yet know the full impact on human health, but the findings from this study suggest a need for urgent action. While research continues, the best thing we can do is reduce plastic exposure and push for solutions to stop plastic pollution at its source.

The next time you drink from a plastic bottle or open a plastic-wrapped snack, remember—some of that plastic may never leave your body.

Would you like to see a future where our brains stay plastic-free? At activist360, we sure would!

Nihart, A. J., Garcia, M. A., El Hayek, E., Liu, R., Olewine, M., Kingston, J. D., Castillo, E. F., Gullapalli, R. R., Howard, T., Bleske, B., Scott, J., Gonzalez-Estrella, J., Gross, J. M., Spilde, M., Adolphi, N. L., Gallego, D. F., Jarrell, H. S., Dvorscak, G., Zuluaga-Ruiz, M. E., … & Campen, M. J. (2024). Bioaccumulation of microplastics in decedent human brains. Nature Medicine. https://www.nature.com/articles/s41591-024-03453-1?error=cookies_not_supported&code=79978c49-7500-4963-807e-3de1d60b6782

How Fossil Fuels, Plastics, and Agrichemicals Delay Climate Action

January 26, 2025 / activist360

Split-screen visual with two contrasting scenes: Left Side: A sandy beach littered with plastic waste, including plastic bottles, straws, and various other trash items, emphasizing pollution and environmental degradation. Right Side: A serene and clean beach at sunset, with a golden sun reflecting on the calm waves of the ocean, symbolizing natural beauty and a sustainable, unpolluted environment. The image symbolizes the contrasts between environmental harm and the potential for a clean, thriving ecosystem.

Unmasking Climate Obstruction

Climate change is one of the most pressing issues of our time, but did you know that some of the biggest industries in the world are working together to block meaningful action? Fossil fuels, plastics, and agrichemicals are deeply connected, and they often use clever strategies to delay or deny the need for urgent climate action. These industries are obstructing progress and impacting on our planet as well as the health of ourselves and our loved ones.

Fossil Fuels and Climate Change

The Root of the Problem

Burning fossil fuels like coal, oil, and gas is the main driver of climate change. These fuels release greenhouse gases, such as carbon dioxide, into the atmosphere. These gases trap heat, causing the Earth’s temperature to rise. This leads to more extreme weather, rising sea levels, and harm to ecosystems and biodiversity.

But the problem doesn’t stop there. The fossil fuel industry is deeply connected to two other major industries: plastics and agrichemicals. Together, these industries form a powerful network that resists policies aimed at reducing fossil fuel use.

Plastics and Agrichemicals: Hidden Contributors

Plastics and Pollution

Plastics are made from fossil fuels, and their production contributes significantly to climate change. Every year, millions of tons of plastic waste end up in our oceans, harming marine life and ecosystems. Over time, plastics break down into tiny particles called microplastics, which pollute water, soil, and even the food we eat.

Agrichemicals and Their Impact

Industrial farming relies heavily on chemicals like fertilizers and pesticides, which are also made from fossil fuels. These chemicals can contaminate water sources, harm wildlife, and disrupt ecosystems. For example, pesticides can kill beneficial insects like bees, which are crucial for pollinating crops. Fertilizers can cause algal blooms in water bodies, leading to “dead zones” where marine life cannot survive.

How Industries Block Climate Action

Social Media and Misleading Messaging

Companies in these industries often use social media platforms like X to spread messages that downplay the urgency of climate action. They ignore the problem of our reliance on fossil fuels. For example, ExxonMobil has promoted carbon capture technology as a solution, but this technology is not yet widely used and doesn’t address the continued extraction of fossil fuels.

Shifting Blame to Individuals

Instead of taking responsibility, these industries often shift the blame to individuals. They might encourage people to recycle more or use less water, while ignoring their own role in creating pollution and climate change. This tactic distracts from the need for large-scale, systemic changes.

Greenwashing

Many companies engage in “greenwashing,” where they make themselves appear environmentally friendly without taking meaningful action. For instance, they might highlight small sustainability projects while continuing to expand fossil fuel production. This creates a false impression that they are part of the solution, when in reality, they are part of the problem.

Lobbying Against Change

These industries spend millions of dollars lobbying governments to resist stricter environmental regulations. They argue that such rules would hurt the economy and cost jobs, even though these regulations are essential for protecting the planet and public health.

Impact on Biodiversity and Health

Harm to Wildlife

The production and use of fossil fuels, plastics, and agrichemicals have devastating effects on biodiversity. For example:

Plastics harm marine life, with animals like turtles and seabirds often mistaking plastic for food.
Pesticides kill beneficial insects like bees, which are vital for pollinating crops and maintaining ecosystems.
Fossil fuel extraction destroys habitats and contributes to deforestation, threatening endangered species.

Health Risks

These industries also pose serious risks to human health:

Air and water pollution from fossil fuel extraction and processing can cause respiratory diseases and other health problems such as cancer.
Chemicals from plastics and agrichemicals can contaminate drinking water and food supplies, leading to long-term health issues, including cancer.

What Can We Do?

Raise Awareness

One of the most important steps is to raise awareness about how these industries work together to block climate action. Share articles like this one, and talk to friends and family about the issue. The more people know, the harder it will be for these industries to continue their obstruction.

Support Stronger Regulations

Advocate for policies that limit fossil fuel production and promote clean energy. Contact your local representatives and let them know that you support stricter environmental regulations.

Reduce Your Reliance on Plastics and Chemicals

While individual actions alone won’t solve the problem, they can still make a difference. Reduce your use of single-use plastics, choose organic foods when possible, and support sustainable farming practices.

Hold Companies Accountable

Support organizations and campaigns that hold fossil fuel, plastic, and agrichemical companies accountable for their actions. Look for brands that are genuinely committed to sustainability and avoid those that engage in greenwashing.

Summing Up

The fossil fuel, plastics, and agrichemical industries are deeply connected and often work together to resist climate action. They use social media, lobbying, and misleading messaging to delay or deny the need for urgent action, all while continuing to harm the environment and public health. To address climate change, we need to look beyond just energy and focus on the entire petrochemical industry, including plastics and agrichemicals.

By raising awareness, supporting stronger regulations, and making sustainable choices, we can push back against these industries and work toward a healthier, more sustainable future. Together, we can unmask climate obstruction and demand real action for our planet.

Source: Kinol, A., Si, Y., Kinol, J., & Stephens, J. C. (2025). Networks of climate obstruction: Discourses of denial and delay in US fossil energy, plastic, and agrichemical industries. PLOS Climate, 4(1), Article e0000370. https://journals.plos.org/climate/article?id=10.1371/journal.pclm.0000370.