APES 8.7

what are PCBs?

1) Additives in paint and plastics, released into aquatic ecosystems by industrial wastewater 2) Toxic to fish, causing spawning failure and endocrine disruption 3) Reproductive failure & cancer in humans - Human exposure comes through animal products

Examples of POPs:

1) DDT (outdated insecticide) 2) PCBs (plastic/paint additive) 3) PBDEs (fire-proofing) 4) BPA (plastic additive) 5) Dioxins (fertilizer production & combustion of waste and biomass) 6) Phthalates (Plastics) 7) Perchlorates (rocket/missile fuel, fireworks)

what are Perchlorates?

1) Given off by rockets, missiles, and fireworks 2) Especially common near military testing sites or rocket launch pads 3) Remain in soil and can leach into groundwater or runoff into surface waters

what are Dioxins POPS:

Byproduct of fertilizer production & burning of medical waste, FFs, biomass - 90% of human dioxin exposure comes from animal fats (meat, dairy, fish) since dioxins buildup in animal fat tissue

why are POPs so dangerous

Fat-soluble, meaning they also accumulate and persist in animals' fat tissue instead of passing through the body (don't easily dissolve into blood/urine) Can slowly be released from fatty tissue into bloodstream and impact the brain & other organs over time (esp. reproductive system)

Explain why the release of PCBs into an aquatic ecosystem may have longer-lasting negative impacts on organisms than the release of synthetic nitrates.

PCB bind to soil and other particles in the water but only small amounts will dissolve in water. Small concentrations of PCBs can also evaporate and be carried long distances in the air. PCB stay longer in the soil and sediments more than nitrate. - When PCB is inside the ocean or aquatic environment,the fish or water organisms will absorb it from the water and sediments in their habitat. Too much accumulation of it can lead to their death and when such aquatic organisms are consumed, it will prone bad health to humans and even foetus. Over accumulation of PCB will affect the heat of individual.

How do POPs travel?

POPs travel long distances through wind & water, impacting ecosystems far away - Wastewater release from industrial processes, leachate from landfills or improperly buried industrial waste, fertilizer/pesticide production, emissions from burning waste/biomass - Enter soil/water, eaten by animals, stored in their fat, eaten by humans or taken in via drinking water

What does POPs stand for?

Persistent (long-lasting) Organic (carbon-based) Pollutants

why are persistent organic pollutants (POPs) long lasting

Persistent organic pollutants (POPs) do not easily break down in the environment because they are synthetic, carbon-based molecules (such as DDT and PCBs). Persistent organic pollutants (POPs) can be toxic to organisms because they are soluble in fat, which allows them to accumulate in organisms' fatty tissues. Persistent organic pollutants (POPs) can travel over long distances via wind and water before being redeposited.

what are Medications (Pharmaceutical compounds) POPs:

Steroids, reproduct. hormones, antibiotics, that pass through human bodies & into sewage release from treatment plants - Persist in streams/rivers & disrupt aq. organisms' endocrine function

what are POPs?

Synthetic (human-made) compounds that do not easily breakdown in the environment; accumulate and buildup in water & soil

what is DDT?

pesticide DDT was widely used as an insecticide before phaseout in most dev. nations - Still persists in soils & sediments in aq. ecosystems and builds up in food webs