Sponges In Polluted Water: Survival Or Extinction?

Sponges are among the most abundant benthic animals, able to live in tropical zones, coral reefs, rocky shores, and even artificial structures. They are also one of the most common indicators of pollution in marine coastal areas. Sponges can filter a large volume of water, with one kilogram of sponges able to process over 24,000 litres per hour. They can withstand polluted habitats with the help of ammonia-oxidizing microorganisms and have been shown to accumulate other pollutants. Sponges are also sensitive to changes in their environment, such as water temperature, acidity levels, and the presence of pollutants, which can cause changes in their cellular structure and biomarkers. With increasing pollution from fertilizers, oil spills, and human waste, understanding the impact on sponges and the potential for sponges to be used in bioremediation is a growing area of research.

Sponges can act as bioindicators for pollutants

Sponges are among the most abundant benthic animals, able to live in a variety of habitats, including tropical zones, coral reefs, rocky shores, and even artificial structures. They are also able to filter a great volume of water, with one kilogram of sponges capable of processing over 24,000 liters per hour. This makes them ideal candidates for bioindicators of pollutants.

Bioindicators are local organisms that are collected and analyzed to determine their level of exposure to pollutants. They are used in a process called biomonitoring, which is necessary for consistent monitoring of persistent organic pollutants in marine coastal areas. Invertebrates like sponges are often used as bioindicators because they have a higher capacity to accumulate contaminants than vertebrates.

Sponges are particularly effective bioindicators because they are sessile animals and are widely distributed across all aquatic habitats. They are also able to withstand polluted habitats due to ammonia-oxidizing microorganisms that live inside them. Sponges can incorporate fine foreign particles, including microparticulate pollutants, which are a growing threat to the world's oceans. These micropollutants are defined as man-made substances or products of their degradation, smaller than 5mm in size, and include microplastics, textile fibers, and particulate toxins that leach from household and cosmetic products.

A study conducted in 2020 analyzed 15 coral reef demosponges around Bangka Island in Indonesia and found that the sponges had accumulated and embedded very fine sediment ( < 200 µm) in their ectosome (outer epithelia) and spongin fibers (skeletal elements). Another study identified 34 different particle types, including polystyrene, particulate cotton, titanium dioxide, and blue-pigmented particles. These particles were not found in the surrounding sand, indicating that the sponges had effectively captured and retained these microparticles.

In conclusion, sponges have a strong potential to be used as bioindicators for biomonitoring microparticulate pollutants in aquatic environments. Their ability to filter large volumes of water and accumulate foreign particles makes them ideal for detecting and monitoring pollution levels in their habitats.

They can be used for bioremediation to clean polluted water

Sponges are among the most abundant benthic animals, able to live in tropical zones, coral reefs, rocky shores, and even artificial structures. They can filter a great volume of water: one kilogram of sponges can process over 24,000 litres per hour. Sponges are also found in a wide variety of colours, shapes, and sizes and are often mistaken for plants.

Sponges can be used for bioremediation to clean polluted water. Bioremediation is a process in which organisms are used to remove pollutants. Sponges are ideal for this because their pores are big enough to absorb large pollutants, such as bacteria or oil droplets, without clogging. In fact, researchers have found that sponges can absorb substances better than oysters. For example, one sponge stood out in laboratory tests due to its ability to filter lead and biological agents, including the bacteria E. coli and Vibrio aestuarianus, which kill shellfish.

Sponges have also been found to be effective in removing microparticulate pollutants, such as microplastics, from water. In a study, the Mediterranean sponge Petrosia ficiformis was found to have accumulated 30.6% of the inoculated microplastic particles after 72 hours.

In addition to removing pollutants, sponges can also help preserve water quality by filtering water, collecting bacteria, and processing carbon, nitrogen, and phosphorus. This is especially important in nutrient-depleted coral reefs, where sponges can make carbon biologically available by excreting a form of "sponge poop" that other organisms feed on, thereby fuelling productivity throughout the ecosystem.

Researchers are studying the possibility of using sponges on an industrial scale for water purification. One example is the development of low-cost sponges by Pavani Cherukupally, which can remove pollutants from water. These sponges are made of plastic and coated with another material that has a surface chemistry complementary to the pollutant. This allows the bacteria or oil droplets to stick to the sponge quickly, while at the same time repelling water. The coated sponge absorbed 90-99% of tested oil within 3 hours and could be easily cleaned with a solvent and reused without any loss of absorbency.

Sponges can withstand polluted habitats

Sponges have a unique ability to withstand polluted habitats thanks to the help of ammonia-oxidizing microorganisms. They can also withstand polluted habitats because of their ability to accumulate significant quantities of pollutants. This makes them ideal bioindicators for persistent pollutants. Regular sampling of the sun sponge along the Rio de Janeiro coasts, for example, will provide a more holistic and detailed profile of PAH contamination than the brown mussel as offshore oil exploration in the region continues to grow.

Sponges are also being studied for their potential use in bioremediation, where they can be used to remove pollutants from water. Researchers are working on developing low-cost sponges that can remove pollutants from water. The core concept is that they fill with polluted water, then the pollutant sticks to the sponge surface. The cleaned water is squeezed out, and then the pollutant is washed off the sponge with a solvent and collected for reuse.

Sponges are also being used to study the potential impacts of climate change on marine environments. Because sponges are so sensitive, they can detect even the slightest variances over a long period of time, variances that may have otherwise gone unnoticed.

They can detect even the slightest variances in water

Sponges are incredibly sensitive to their environments. They can detect even the slightest variances in water over a long period of time. This makes them ideal bioindicators for persistent pollutants. Their strong skeletal structures help them withstand the high volume of water that flows through them each day.

Sponges are among the most abundant benthic animals, able to live in tropical zones, coral reefs, rocky shores, and even artificial structures. They can be found in a wide variety of colours, shapes, and sizes and are often mistaken for plants. Certain species have a fossil record that dates back approximately 600 million years to the earliest (Precambrian) period of Earth’s history.

Sponges are filter feeders, meaning they extract and retain particles from the water column, across a broad size range. They can filter a great volume of water: one kilogram of sponges can process over 24,000 litres per hour. This makes them excellent candidates for biomonitoring, where local organisms are collected and analysed to determine their level of exposure to pollutants.

In a laboratory setting, researchers can artificially increase water temperatures, add pollutants, or alter acidity levels to reflect the predictions of climate change. They can then observe any changes in the cellular structure of sea sponges to determine the impact of these changes. For example, sponges may exhibit changes in colour, shape, size, attachment, and the release of protective proteins in response to stressors.

The sensitivity of sponges to their environment and their ability to accumulate pollutants make them valuable tools for monitoring water quality and predicting future changes to marine environments.

Sponges can be used to deliver clean water

Sponges are among the most abundant benthic animals, able to live in a variety of habitats, including tropical zones, coral reefs, rocky shores, and even artificial structures. They are also incredibly efficient at filtering water, with one kilogram of sponge able to process over 24,000 litres of water per hour. This makes them ideal for delivering clean water.

Sponges have a porous exterior that allows water to pass through, bringing the sponge food and oxygen and carrying away waste. Tiny hair-like structures called flagella create currents that filter bacteria out of the sponge's cells and trap food within them. This filtering process is so effective that sponges are now being considered for use in water purification systems, particularly in low-income economies or off-grid communities.

Sponges have been shown to accumulate significant quantities of pollutants, including microplastics, pesticides, medicines, and chemicals. This ability to absorb and retain particles from the water column makes them excellent candidates for bioremediation, a process where organisms are used to remove pollutants from the environment. By using sponges to absorb and trap pollutants, clean water can be squeezed out, and the pollutants can be washed off the sponge for safe disposal or reuse.

To enhance the effectiveness of sponges in delivering clean water, researchers are designing sponges with specific surface coatings. These coatings are engineered to have a complementary surface chemistry to the target pollutant, causing the pollutant to stick to the sponge while repelling water. For example, Pavani Cherukupally is working on developing low-cost sponges coated with materials containing chemical groups like carboxy and amine, which change charge depending on the pH. These engineered sponges have been shown to effectively remove bacteria from water, with the process being more efficient in acidic conditions.

The use of sponges to deliver clean water offers a cheaper and simpler alternative to current water purification technologies, which can be expensive and time-consuming. By deploying these sponges on an industrial scale, communities around the world could gain improved access to basic clean water and sanitation, helping to address the UN Sustainable Development Goal 6 and reduce the impact of waterborne diseases.

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