(F) 22 - Plastic Pollution

Question 1

What is plastic made of, and why is it so challenging to recycle?

Answer 1

Plastics are polymers
- strong, light and durable which makes them so useful and so problematic
- can only recycle a small percentage

Question 1

The plastic cycle: what it is, and why it is important to acknowledge

Answer 1

The continuous and complex movement of plastic materials btw different abiotic and biotic ecosystem compartments, including humans.
- land to ocean to sediment (biogeochemistry, trophic transfer, human health)

Must consider the plastic cycle like any other biogeochemical cyle
- to help identify the relationships btw plastic manufacturing and pollution to serious environmental problems
- for the potential ramifications on policy development and management
- as a foundation for the development of thoughts, ideas, and sustainable solutions

Question 2

Impacts of plastic on wildlife, at different levels of organization; potential impacts on us

Answer 2

Subcellular
- oxidative damage
- altered gene expression

Cellular
- elevated antioxidant responses
- altered cellular division
- apoptosis
- stress response
- altered fatty acid metabolism

Individual
- altered feeding
- increased metabolic demand
- reallocation of energy resrves

Population
- reduced growth
- decreased reproductive output
- reduced offspring viability
- population decline

Question 3

Classification of plastics based on size

Answer 3

nano, micro, meso, macro, plastics

Nanoparticle: <1um in diameter
Microparticle: btw 1-5000um in size

Question 4

Focus on nanoplastics/microplastics:
- sources and fate in the environment
- how they enter the human body
- microbeads, plastic fibers, degraded plastic

Answer 4

Sources and Fate
- come from secondary sources due to degradation of larger plastics

How they enter:
- ingestion
- inhalation
- skin contact

Microbeads (microparticle)
- made of polyethylene; problem is they don’t degrade
- found in a lot of skin care
- easily ingested by filter feeders, not digested, can end up in food chain and accumulate in gut
- often too small and lightweight to be removed by standard wastewater treatments

Plastic fibers
- similar to microbeads; consumed by filer feeders, don’t degrade, move up food chain
- clothing

Degraded Plastics
- degraded by UV, resulting in smaller pieces that can aggregate and potentially precipitate
- benthic organisms can influence the partitioning of microplastics btw water column and sediments

Question 5

Focus on plastic use during the covid19 pandemic: types of plastics, impacts on plastic waste management

Answer 5

Types:
- biomedical wastes

Impact
- managing all the extra plastic waste worldwide; increased load on waste dumps and landfills

Question 6

Possible solutions to plastic pollution

Answer 6

1. vote with your $
   - read labels and look for ingredients such as polyethylene
   - buy merino wool
   - care for your clothing
2. cooperation across sectors (gov/policies, education, waste management, research, producers, consumers etc.)
3. strategies towards zero goal
   a. reduce plastic production
   b. innovative materials and product design
   c. reduce waste generation
   d. improve global waste management
   e. improve litter capture
   f. reduce input concentrations into oceans (zero goal)