FIGURE 29: IMPACTS OF MACRO AND MICRO PLASTIC
FISHERIES AND AQUACULTURE
MARINE TOURISM ECONOMIC IMPACTS SHIPPING
MACROPLASTICS
PLASTICS IN THE OCEAN
SECONDARY MICROPLASTICS
CLEAN UP COST
ENTANGLEMENT
INGESTION: DIGESTIVE SYSTEM IMPACTS
PRIMARY MICROPLASTICS
PHYSICAL IMPACTS
TRANSPORTATION OF INVASIVE SPECIES
PBTs SUBSTANCES DESORPTION
INCLUDED IN THE VALUATION MODEL MATERIAL BUT NOT INCLUDED IN THE VALUATION MODEL
ADDITIVES LEACHATE
CHEMICAL IMPACTS
MONOMER LEACHATE
ECOLOGICAL IMPACTS Plastics in the ocean generate economic impacts which are often paid by those affected rather than plastic producers or consumers. Economic impacts relate to the loss of revenue caused by marine plastics. Industries concerned by this issue are fisheries and aquaculture, marine tourism and shipping. Additionally, plastics litter on beaches will imply clean-up costs.5 ECOLOGICAL IMPACTS Ecological impacts refer to the morbid or lethal effects endured by marine biodiversity. These impacts can be broken down into physical impacts, referring to the impacts coming from the shape of plastics objects, and into chemical impacts, referring to the impacts coming from the toxic substances present in the plastic. PHYSICAL IMPACTS Entanglement: marine biodiversity such as marine mammals can be entangled, which can lead to suffocation, starvation, drowning or increased vulnerability to predators. Ingestion: marine species can ingest plastic by mistaking it for food. This can lead to starvation, malnutrition or internal injury.6 Transportation of invasive species: floating plastic can act as vector of invasive species which would alter community structure.6 This impact has not been included in the valuation model due its complexity and for lack of quantitative data. CHEMICAL IMPACTS Persistent Bioaccumulative Toxic substances (PBTs) desorption: plastics can act as a carrier for the ingestion of PBTs.25 PBTs are chemicals that degrade slowly in the environment and accumulate in organism tissues. Due to industrial activity, the oceans now have varying concentrations of PBTs to which marine life is already exposed. However, due to its chemical characteristics, plastic in the ocean absorb these PBTs increasingly over time. If the plastic is then ingested by marine wildlife, PBTs can be transferred to the animal and potentially bio-accumulate further through the food chain. While PBTs absorption and desorption impacts are likely to be more material that additives leachate, the data available was specific to certain situations, and did not lend itself to broad-based application through the valuation model. Research in this field is constantly evolving. Additives leachate: additives are chemicals added to plastic feedstock in order to enhance their properties including but not limited to heat and corrosion resistance, hardness and colours. The quantity of additives varies based on the type of plastic and its usage – for example plasticisers are often used in PVC products to improve flexibility and flame retardants in electronics and automobiles for safety reasons.
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