21 microplastics & phthalates Flashcards
what is the outline of this lecture?
-microplastics and phthalates
-where do they come from?
-how do they contaminate the environment?
-what are the major pathways of exposure?
-what are their toxicological impacts?
-what are the current regulatory strategies?
what are the size categories of plastic pollution?
what are microplastics?
-microplastics are tiny pieces of plastic smaller than 5mm in diameter
what are the types of microplastics?
what are the sources of primary microplastics?
what are the sources, routes and fate of MPs in the environment?
which country emits the most plastic waste in the ocean?
we send out to be processed by separate parts of the world (illegally)
-more than 1000 rivers account for 80% of global riverine plastic emissions into the ocean
where do the ocean’s microplastics come from?
what are the impacts of microplastics?
-ingestion by organisms and/or trophic transfer
-vectors for toxins/pathogens
-gets attached, clogs gills; affects movement, behavior, body (fitness)
what are the adverse effects on fish?
adverse physiological effects:
-behavioural, sensory and neurological functions
-intestinal permeability and gut microbiome diversity
-metabolism and growth
what is the occurrence, human exposure and risk of microplastics in the indoor environment?
what are the MPs in food and beverage?
how many nanoplastics do we drink from water bottles?
filters used for water was a major source of MPs in water
what are the potential human health effects based on rodent studies?
disrupts gut epithelium
-more permeable=very problematic
-glucose spikes, so insulin goes up
what is very dangerous about plastic shards?
highest amount in brain
what are the pathways of human exposure to MPs and associated risks?
what are the regulatory challenges of MPs?
-no universally accepted definition of MPs
-no standardized analytical techniques for detection
-lack of understanding of what factors influence their bioavailability
-toxicological information is extremely limited
-regulatory strategies are rudimentary!
what are phthalates?
what are commonly used phthalates?
high molecular weight (HMW): 9-13 C atoms
-used to make vinyl plastic more flexible
low molecular weight (LMW): 3-8 C atoms
-used as solvents in personal or cosmetics care products
what are the chemical properties of phthalates?
where are phthalates used?
how are plastics formed (phthalates)?
