class 10 Flashcards
What common uses does Bisphenol A (BPA) have?
BPA is used to make polycarbonate plastics and epoxy resins found in food containers, water bottles, and many other items.
How are people most commonly exposed to BPA?
Through ingesting food and drinks stored in containers made with BPA, inhaling dust, and skin contact with items like receipts.
What happens to BPA once it enters the human body?
Most of it is quickly broken down and excreted in urine within 24 hours, with less than 5% being absorbed.
How does BPA potentially affect the brain?
Studies suggest BPA can disrupt the endocrine system, mimicking or blocking hormones and possibly affecting brain structure, function, and behavior.
What are microplastics, and how do they differ from nanoplastics?
Microplastics are tiny plastic particles under 5mm, while nanoplastics are even smaller, under 100 nanometers. Both can come from the breakdown of larger plastics or be manufactured for specific uses.
How might humans be exposed to microplastics?
Through eating contaminated food, drinking water, breathing air with microplastic dust, and through skin contact.
Can microplastics be found in human tissues?
Yes, studies have shown that microplastics can enter the body and have been found in organs and tissues, including the brain.
What are the potential health impacts of microplastics on the brain?
Early research in animals suggests microplastics can lead to brain inflammation, alter behavior, and potentially impair learning and memory.
How do microplastics enter the brain?
They might enter through the bloodstream or potentially cross the blood-brain barrier by mimicking substances the body naturally transports into the brain.
Are there studies on the effects of microplastics on human brain development?
Research is limited, but the presence of microplastics in breast milk and the placenta suggests a need for studies on their impact on neurodevelopment.
Why is BPA considered an endocrine disruptor?
BPA can mimic or interfere with the body’s natural hormones, like estrogen, disrupting the normal functioning of the endocrine system.
How do microplastics become a part of the food chain?
Microplastics enter waterways, where they are ingested by aquatic life, eventually making their way up the food chain to humans.
What are some sources of microplastic pollution in the environment?
They come from the breakdown of larger plastic waste, synthetic fibers from clothes, cosmetics, and industrial processes.
What effects do BPA and microplastics have on brain structure?
Exposure can lead to changes in dendrite morphology, spine density in the brain, and possibly affect neuron viability and behavior.
How do BPA and microplastics exposure differ in terms of health risk assessment in Canada and Europe?
Europe’s safety threshold for BPA exposure is significantly lower than Canada’s, suggesting different assessments of health risks associated with BPA.
What role do phthalates play in the context of endocrine disruption?
Phthalates, like BPA, can interfere with hormone activity, affecting the production, secretion, and function of natural hormones.
How does adolescent exposure to BPA differ in effects compared to prenatal exposure?
Adolescent exposure can specifically impact cognitive functions and synaptic plasticity, indicating that the timing of exposure alters BPA’s effects.
How are microplastics detected in human bodies?
Through analyzing tissues, blood, and other bodily fluids, indicating widespread environmental exposure.
What potential pathways allow microplastics to affect brain health?
They may induce neuroinflammation, alter neurotransmitter levels, and disrupt normal brain function and behavior.
How does the environmental persistence of microplastics complicate their impact on health?
Their durability and resistance to degradation mean they can accumulate in ecosystems and the human body, posing long-term health risks.
How do BPA and microplastics potentially impact human reproduction?
They may disrupt hormone-regulated reproductive processes, leading to fertility issues and altered development of reproductive organs due to their endocrine-disrupting properties.
Can washing synthetic clothes contribute to microplastic pollution?
Yes, washing synthetic fibers releases microplastics into wastewater, which can end up in aquatic environments and contribute to pollution.
What are the environmental sources of BPA exposure for humans?
BPA exposure can come from food and beverage containers, water bottles, the lining of canned foods, dental sealants, and thermal paper products like receipts.
How does the size of microplastics influence their potential toxicity?
Smaller microplastics are more likely to be absorbed, distributed, and accumulate in the body, potentially leading to greater toxicity due to their ability to penetrate cells and tissues more easily.
