Publication - Research and analysis

Marine plastic pollution: research

Research on the plastic value chain in Scotland to better understand this landscape and the potential for intervention to address marine plastic pollution.

Marine plastic pollution: research
3. Research Findings

3. Research Findings

Research Findings


Of the products studied, key pollution points in the supply chain commonly occur during their use and at the end of life. Considering this in isolation would suggest the consumer or end user is responsible for stemming the tide of marine litter. The research found that the drivers for this pollution were heavily influenced by decisions made further up the supply chain. For example, the loss of microplastic crumb from artificial pitches during use could be avoided or reduced through different design and procurement decisions. There is a disconnect, however, between who bears the additional cost of the mitigations and the wider society who benefit from the reduced microplastic (or the avoided cost of not dealing with the clear up).

Commercial fishing gear

Commercial fishing gear is regularly found in marine litter surveys and is particularly problematic due to the long lasting impacts of ghost fishing, ingestion and entanglement. Modern nets and fishing gear typically contain a mixture of different plastic polymers. Gear may be lost accidentally but there are also reports of it being intentionally dumped at sea or sabotaged by other users of the marine environment. The research found stakeholders, including large and small fishing groups, ports and harbours, environmental groups and academic researchers, net producers and waste management businesses were positive about taking action to tackle marine plastics from fishing.

Fishing is a dangerous activity and risks of injury or worse are increased when handling damaged gear, therefore it is not always possible to recover lost nets or gear, even if the gear hasn't yet been swept away. However, much of the gear used by Scottish vessels is expensive to dispose of both in terms of cost, time and access to appropriate infrastructure. No strong incentive currently exists, other than environmental stewardship, to dispose of nets appropriately. This increases the risk of nets being lost at sea or being stored indefinitely in secure or insecure locations (sheds or on the harbour side).The Scottish Government is working as part of our British Irish Council commitment to improve recycling opportunities for fishing gear and to address the knowledge gap around how much fishing gear is in storage, how much is bought each year and how it is managed around Scotland.

Peterhead Port was an exemplar in this area. A pilot was underway raising awareness of the problem with fishers and the local community. Infrastructure and space was provided for vessels to land their waste and a 'leader board' was used to recognise good behaviour among the fish vessels operating from the port. Harbour dues include a flat fee for waste disposal meaning that fishers aren't penalised for responsible waste disposal.

Not all ports however can afford to offer this services on a flat fee or indeed have the infrastructure required to handle large quantities of waste such as fishing nets at end of life. Furthermore, even if waste is managed appropriately the vast majority currently ends up in landfill.

Menstrual products

In the 2018 MCS Great British Beach Clean survey[1], sewage related debris (menstrual products included) accounted for 12.6% of coastal litter in Scotland, compared with a UK average of 6.2%. In a survey of the public conducted as part of this research, 24% of respondents indicated that they always or frequently flushed tampons and 9% always or frequently flushed sanitary towels. Once flushed down the toilet they can cause blockages in the sewage network and may be discharged to waterways either via combined sewage overflows or occasionally from passing through waste water treatment. Plastics are found in the actual tampons and pads, as well as in applicators and wrappers. Plastic-free versions are available but are less popular in Scotland, potentially due to convenience, habit and marketing behaviour. Similarly, reusable cups and period pants are available but their market share is so far small.

The upfront cost of reusable cups and pads are higher than single use products but over the length of time in use are significantly cheaper. Whilst this is good for the consumer over the longer term, if the upfront cost is affordable, this represents a significant revenue loss to suppliers in this market. This is illustrated by the research findings around the number of new businesses supplying the reusable and plastic free menstrual product market compared to the incumbent suppliers largely resisting changing their main offer. Further, competitive advantage is gained by including plastic elements to increase perceived user convenience.

Zero Waste Scotland recently ran the "Trial Period" campaign[2] which aimed to raise awareness of and encourage the use of reusable menstrual products. The campaign also involved distributing 2,000 reusable products for people to trial and encouraging them to complete a survey to gather experiences.

Artificial Pitches

Artificial grass pitches are a valuable resource in Scotland helping to keep our population fit and active all year round. Modern pitches are manufactured using plastic-based crumb to improve the playing surface for performance and safety. This plastic-based crumb can be lost from pitches on players boots and clothes or by wet and windy weather. It can then find its way down drains either in the street or through showers and washing machines. Losses also occur at the end of pitch life during removal, transportation and storage – if not handled and managed appropriately.

A key issue was highlighted regarding improper waste management of these pitches. It was suggested that some companies are transporting and disposing of pitches illegally in storage facilities. Better enforcement and audit of waste transfer notes could reduce the incentives of managing waste in this way.

Mitigations are available in the form of: designs to minimise the loss of the plastic-based crumb during use i.e. barriers and scrapers for shoes; alternative materials, and; next generation pitches. However, these mitigations are not being implemented as there is little understanding of the problem at the key points in the value chain.

The installation and disposal of pitches in Scotland is largely procured by local authorities. Maintenance may also be included as part of the same contract. Discussions at the workshop suggested that procurement exercises are driven almost entirely by cost whilst environmental issues are not valued. This puts any suppliers wishing to improve the sustainability of pitches at a competitive disadvantage. Even if the mitigations are cost neutral, the understanding is not there to counter the risk of a slightly different product.

Fidra[3], a Scottish environmental charity based in East Lothian, together with KIMO International[4] have produced best practice guidelines for minimising plastic loss from artificial pitches. They have also developed "Pitch In!", a community toolkit to engage the public and users of pitches and provide some practical examples of ways to reduce plastic loss.[5] The research highlighted the need for better standards on environmental requirements in procurement and pitch management since the industry is so cost competitive.

Crisps, snack and sweet wrappers

Wrappers are consistently one of the top categories identified in marine litter surveys. They are mostly used on products that are designed to be eaten on the go meaning that packaging is required per serving and must be designed to keep the product fresh, protected from damage, light-weight and appetising. These attributes mean that materials containing plastic are most commonly used and unfortunately these materials are also very difficult to recycle and therefore have little value after being used as a wrapper.

Very little of the value chain for this product category is located within Scotland. Initial research identified few opportunities for Scottish Government to act on marine plastic originating from this industry. International brands are less likely to voluntarily modify product design to suit one market and so international collaboration would be required to create change in this industry. Scotland could take the opportunity to show leadership in this area by engaging international action.

As with other products there is no single silver bullet and any intervention would benefit from a holistic approach. The research identified the following recommendations for crisp, snack and sweet wrappers: voluntary agreements, packaging innovation, increasing recyclability and extended producer responsibility. A pan-UK consultation on reforming the UK packaging producer responsibility system closed in May 2019, the research noted that industry are currently waiting for a clear steer from government on future directions.