Green mussels or locally known as “tahong” or green mussels shells in the Philippines were tested 100% positive for microplastics. The recent findings follow with information gathered across different countries relating to global marine pollution.
The Philippine study was conducted on three samples across three different locations—two of which were tested positive for microplastics while the third set tested positive for “suspected microplastics.”
The study was conducted by Dr. Jose Isagani Janairo from the De La Salle University in coordination with the Philippine Department of Science and Technology (DOST). Furthermore, the researchers conducted the experiment using Fourier-transform infrared spectroscopy (FTIR).
“This is the first time we encounter analyzing samples with possible contamination of microplastic in the tahong or green mussels shells using FTIR,” said Dr. Araceli Monsada, director of the DOST-Advanced Materials Testing Laboratory.
Fourier-transform infrared spectroscopy or FTIR is a widely used technology in detecting microplastics since fragments are too small that they are invisible to the naked eye. Other countries, such as the UK and China, also conducted studies regarding the matter.
The microplastic identified in the study were Polyethylene or PET. Janairo describes this type of plastic as a resource commonly used in making plastic bottles, textiles, and fabrics.
The discovery raises attention towards possible health risks from consuming mussels with microplastics in its system. Janairo says that it is likely that humans will digest microplastics while eating mussels.
From a different perspective, a study conducted last October 2018 where researchers gathered data on microplastics in mussels from coastal waters and supermarkets in the United Kingdom, discovered that coastal mussels sampled all contain microplastics.
Moreover, supermarket bought mussels for human consumption also all contain microplastics where 43% or 57% of debris items from coastal/supermarket mussels were microplastics. The researchers predicted consumers ingested 70 microplastic items in 100 g processed mussels.
Fortunately, the Philippine Bureau of Fisheries and Aquatic Resources claim that the findings do not pose a threat to human health and remain to be safe for public consumption.
Roy Ortega chief of the BFAR Aquaculture Division urges that the recent findings on green mussels harvested in the Philippines are not something to be worried about unless there is a red tide alert.
However, microplastic levels found in mussels may not affect human health — it affects the health and survivability of the aquatic animal.
Microplastic is an emerging pollutant in marine environments. The continued human pollution in the ocean has led the filter-feeding organisms to consume plastic through tiny amounts. The problem could result in devastating impacts on ocean ecosystems, as well as a worldwide industry worth between 3 to 4 billion US dollars per year.
An article published in Science Daily tells that continued microplastic consumption by mussels affect their ability to attach themselves to their surroundings such as rocks.
The recent research, published in the journal Environmental Pollution, was led by Dr. Dannielle Green of Anglia Ruskin University and was carried out at the Portaferry Marine Laboratory in Northern Ireland.
The study found that increased microplastic consumption by mussels led to the aquatic animal to produce lesser byssal threads, which are thin fibers that help mussels attach themselves to rocks and ropes. This enables the mussels to defend itself against strong waves and tides.
Moreover, the study also noted that byssal threads functioned more than just enabling mussels to have a firm grip unto rocks. The byssal threads also help in creating extensive reefs that provide habitats for other marine animals.
Dr. Green, a senior lecturer in Biology at Anglia Ruskin University, said: “Tenacity is vital for mussels to form and maintain reefs without being dislodged by hydrodynamic forces. Our study showed that the presence of non-biodegradable microplastics reduced the number of byssal threads produced by the mussels, which likely accounts for the 50% reduction in their attachment strength.
“Byssal threads help mussels to form aggregations, increasing fertilisation success and making mussels more resistant to predation. A reduction in these byssal threads in the wild could lead to cascading impacts on biodiversity as well as reducing yields from aquaculture, as mussels are more likely to be washed away by waves or strong tides.”
“Our research also shows that even biodegradable microplastics can affect the health of mussels. Both biodegradable and non-biodegradable plastic are used in making single-use packaging, which if it becomes litter can break down into microplastics. Better recycling and an overall reduction of these materials can play an important role in helping to safeguard our marine environment.”