11. Environmental pollutants Flashcards
What are chemical pollutants called in the new PB framework?
Novel entities
What are novel entities?
New substances or structures that from a natural point of view do not exist.
Name some examples of novel entities
PFAS, pharmaceutical/recreational drugs, chemical waste.
When are novel entities a concern? Name all four reasons.
- Persistence
- Mobility across scales and consequent widespread distribution
- Accumultation in organisms and the environment
- Potential negative impacts on vital Earth System processes or subsystems (e.g. toxicity)
Provide an example for a biological impact of a novel entity.
Decline in top predactors due to widespread use of chemicals (e.g. DDT)
Provide an example for a physical impact of a novel entity.
Reduced light reflection due to emission of black carbon particles.
Provide an example of a chemical impact of novel entity.
Breakdown of ozone by CFC.
Name 2 examples of point sources for novel entities and 2 examples for non-point (diffuse) sources.
Point sources:
- Domestic wastewater discharges
- Combined sewer overflows
- Stormwater discharges
- Industrial discharges
- Spills
Non-point (diffuse) sources:
- Agricultural runoff
- Livestock
- Landfills
- Recreational activities
Provide an example of transportation of a NE.
Wind
Provide an example of a transformation of a NE.
Degradation
Provide an example of exposure to an NE.
Inhalation.
Name 2 classes of (organic) environmental pollutants.
- Endocrine disrupting compounds
- Pharmaceuticals
- Illicit drugs, sweeteners
- Personal care products
- Nanoparticles
- Flame retardants
- Fluorinated compounds
- Organic solvets, complexing agents
- Pesticides
- Microplastics
- Emerging contaminants
According to the EU, what are the 2 strands of pollutants? Provide the acronyms and what each letter stands for.
PBT (stays in body)
- Persistent: remain in the environment for long
- Bioaccumulative: concentrations increase in human or animal tissues
- Toxic: have negative effects
PMT (mobile)
- Persistent
- Mobile: substances can easily move in the environment
- Toxic
What is difficult about mobile substances?
Mobile means substances that are difficult to remove.
Why are pesticides different in contrast to other compunds?
They are meant to kill.
Why are toddlers easily exposed to flame retardants?
Flame retardants are in chairs, dust, etc., and toddlers put things in their mouths.
Name 2 examples of where endocrine disrupters can be found.
- Food preservatives
- Personal care products
- Clothing
- Furniture
- Plastic
- Manufacture
- Resins
- Pharmaceuticals
- Synthetic hormones
- Solvents
- Pesticides
- Herbicides
- Fungicides
- Food packaging
What do endocrine disruptors interfere with?
The natural hormones in the body.
True or false: the chemical industry is the largest manufacturing industry globally?
False.
True or false: production of chemicals has increased tenfold since the 1950s.
False, it has increased 50x.
True or false: production volume of chemicals is expected to quadruble from 2010 to 2050.
False, expected to triple.
Name 3 reasons why plastic pollution is persistent.
- Natural removal is (very) slow
- Clean-up is difficult (because of fragmentation: “weathering” -> becomes brittle after being exposed to environment)
- Plastic can fragment into micro- and nano-plastic
- It is also a poorly reversible pollutant: difficult to go back to safe operating space
Name 3 impacts of plastic pollution
- Long term and global
- Accumulating and poorly reversible
- Wide-reaching: geophysical & biological
- Impacts on nutrient cycling
- Habitat change
- Impacts on carbon cycling (changes in sediment structure)
- Societal impact
- Entanglement
- Starvation
- Pressure on ecosystems already exposed/stressed
What are the definitions of microplastic and nanoplastic?
- Microplastic: plastic particles <5 mm
- Nanoplastic: plastic particles <1 micrometer
Name 2 ‘blind spots’ of microplastic research (terra icognita)
- Nano-sized plastic particle analysis (development phase)
- How reliable (quality) is plastic particle data available
- Spatial and temporal trends (comparable data), sources, sinks
- How microplastics pollution impacts ecosystems
- How to effectively determine human exposure
- What the risk of plastic particles is to human health
- How the current pollution paradigm can be shifted
What does the precautionary principle dictate regarding the use of novel entities?
We shouldn’t use them until we know their effects.
Why is PFAS such a problem? Name 3.
- “Forever chemicals” -> difficult to degrade
- Some bioaccumulate in our organism
- Health effects
Why should PFAS be a planetary boundary? Name 2 reasons.
- Global
- Negative effects discovered now
- Poorly reversible
Why is mixing of chemicals dangerous?
Mixing is dangerous because alone chemicals might not be a harm but mixed they might be dangerous.
What are regrettable substitutions?
Regrettable substitution happen when a hazardous chemical is replaced by something that is also hazardous.
What are the three pillars of Green Chemistry?
- Efficiency
- Safety
- Circularity
