Glowing Plastic Detectives

Glowing Plastic Detectives

Since January, pupils from across Pembrokeshire have been investigating the plastic problem on our beaches with Sam and Amy from the Dragon Darwin Experience and support from Sea Changers.  In a method simplified by the Young Darwinian for use with school groups, pupils used fluorescent tagging to stain and count invisible microplastics in sand samples.  Two classes from Ysgol Llandudoch investigated Poppit Sands, Holy Name Catholic School used Newport Sands, St Mark’s Church in Wales VA School went to Freshwater West and Ysgol Gymunedol Croesgoch sampled Whitesands Bay.

Pupils were taken by coach to a beach of their choosing where they collected weather data, completed field sketches of the beach to be surveyed, before participating in a beach clean using equipment kindly loaned by Keep Wales Tidy.  Microplastics (if present) were swept up from the strandline for use back in class, small samples of sand were collected, and all rubbish bags were weighed.  During the 5 field trips, with 120 pupils, an impressive 95.08kg of litter was removed from Poppit Sands, Newport Sands, Freshwater West and Whitesands Bay.  Following the visit from storm Éowyn, St Mark’s Church in Wales VA School cleared a staggering 42.6kg in 9 rubbish bags, not including the large items they also removed including plastic Gerry cans, fishing boxes and crates from Freshwater West.

After the field trip pupils took part in two different workshops.  The first was an overview of the plastic problem, how it is made, how it enters the sea and impacts on food chains.  Pupils then began their investigation to answer the enquiry question ‘Are there invisible microplastics in the sand at our chosen beach?’  They carefully stained their sand samples with a dye, which were then left to dry until the following workshop.  During the second workshop pupils weighed out 1g of their stained sand and used blue torches and orange filters to look at the sand. When viewed under these conditions, plastics in the sand sample will glow brightly just like a glow stick.  They had the difficult task of counting how many pieces of glowing plastic were present.  Counts were repeated 3 times to improve accuracy, with the mean value recorded into the class results table.  

Following their classroom investigations, pupils discovered that the mean number of pieces of plastic present in 1g of sand on 4 different Pembrokeshire beaches ranged from 20.75 pieces at Freshwater West to 4.87 at Newport Sands with Poppit Sands having a mean on 9.88 and Whitesands Bay with a score of 10.

The importance of studying microplastics was discussed including ways it can enter the food chain, pupils then identified visible microplastics from the strandline and classified them into different groups – nurdles, bio beads and secondary microplastics.  Their final task was to use the ‘Beat the Microbead’ app to scan cosmetic products from home which showed how deep the plastic problem runs, with many popular cosmetic products and brand using microplastics in their ingredients.  To end on a positive, we discussed ways in which we can help solve the plastic problem and reduce our use of plastic products by switching to alternatives and looked at novel ways scientists are trying to solve the plastic problem including a plastic filtering robotic fish to mimicking the foot movement of a Hawaiian apple snail to remove microplastics from the surface of water.

Samantha Williams from the Dragon Darwin Experience said ‘The glowing plastic detectives project provides us with an additional way to highlight and monitor the plastic problem we are facing on our beaches.  Pupils and staff were amazed at how much plastic is actually out there and during discussions on the shore and in the classroom, pupils really thought about how they could be more sustainable both at school and at home, looking at ways to reduce their plastic use and switch to more environmentally friendly alternatives.  It was important for us to show the participants that every small action counts in the fight against pollution, and together, we can make a lasting impact.’