The Seashell Solution

Photo by Joseph Robertson |

Water contamination has been a pressing issue for decades because of its implications for both the health of the environment and the species living within it. Developed countries especially produce large amounts of pollution that eventually find their way into our waterways. We have long been aware that factories produce enormous amounts of pollution that end up in our water supply, harmful chemicals (pesticides, herbicides etc.) which leach into rivers and that other chlorinated solvents make their way into our water systems. Despite our efforts to sample, test and clean sources of drinking water, new pollutants are introduced everyday without our knowledge. 

I read about a proposed solution that was successfully carried out two years ago – the Clam Clean Up. Dr. Hariette Phelps explained that clams were used as “pollutant traps”. Clams are filter feeders, “drawing water into their shells and removing the food they find”. By continuing this process, they can filter large amounts of water. In addition to the food they eat, other compounds in water can be found in the muscle of the clam, which includes pollutants and other toxic substances.

Researchers can then examine these for presence of toxins and identify specific sources of pollution. This method is an inexpensive, efficient way of purifying water, understanding the transfer of pollutants throughout an ecosystem, and the effects of biomagnification – the collection of toxins passed from prey to predator through ingestion. However, there are several problems to address in using this method. 

Firstly, not all species belonging to the class Bivalvia are considered invasive. As such, over usage of these species could lead to a significant depletion in their numbers. In addition, high levels of pollution can translate into high toxin concentrations found in clams.

For this reason, it is important to note that several other species feed on clams, including seagulls, starfish, eels, seals and certain species of fish. This can cause a dangerous accumulation of toxins all across the food chain. Furthermore, humans can be severely affected by ingesting contaminated clams, leading to respiratory diseases and other health problems.

It is important for us to support innovative solutions that use biological resources to resolve environmental problems. However, we must be skeptical about the value of the outcome and mindful of the consequences that might occur. Take some time this month to learn about causes of water pollution in your area and how you can help to circumvent the problem!