ENVS 1100 Lecture Notes - Lecture 3: Rachel Carson, Endocrine Disruptor, Bioaccumulation
3 May 2018
School
Department
Course
Professor
Information Literacy in Science and Statistics
September 11, 2014
CHAPTER 3 REVIEW:
• BPA is a synthetic chemical from the 1940s used to line metal food cans and
production of plastic bottles
• Studies showed an association between BPA and serious medical problems
• BPA was first banned in Canada
• Plastic industry challenged science saying that BPA was perfectly safe
• BPA is an endocrine disruptor (blocks hormone from binding to a receptor so
no proteins may be synthesized)
• BPA has large effects at low doses
We live in an environment full of toxins.
Toxic substances are substances that cause damage to living organisms through
immediate or long-term exposure.
Synthetic toxins – many and persistent; do not degrade over time
Natural toxins – natural does not always been safe; arsenic can cause cancer and
nervous system damage in humans
Rachel Carson wrote a book in 1962, which uncovered some discrete impacts of
DDT and other herbicides/pesticides. DDT is responsible for killing mosquitoes
carrying malaria but can also cause cancer and many other serious health effects. No
one was concerned about the potential issues of DDT while it conquered mosquito-
borne diseases during WWII and combating world hunger by boosting food
production
According to Environment Canada:
• 23,000 chemicals were in commercial use in 1986
• since then, 800-1000 new chemicals have entered the Canadian marketplace
each year
A substance’s solubility (ability of a substance to dissolve in a liquid or gas) must be
considered when discussing the potential damage to the environment. Water-soluble
chemicals may be better for humans because we can excrete them in our urine but
are easily taken up by aquatic environments. Fat-soluble chemicals do not dissolve
in water and are not so easily excreted. These chemicals can build up in the tissues
of organisms (=bioaccumulation).
Biomagnification describes the consequence of bioaccumulation. Animals higher
up on the food chain (predatory animals) consume prey containing a larger amount
of accumulated toxic substance so they have increased levels of this toxin in their
tissues. Therefore, animals higher up on the food chain accumulate far more toxic
substances than those lower on the food chain.
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
We live in an environment full of toxins. Toxic substances are substances that cause damage to living organisms through immediate or long-term exposure. Synthetic toxins many and persistent; do not degrade over time. Natural toxins natural does not always been safe; arsenic can cause cancer and nervous system damage in humans. Rachel carson wrote a book in 1962, which uncovered some discrete impacts of. Ddt is responsible for killing mosquitoes carrying malaria but can also cause cancer and many other serious health effects. No one was concerned about the potential issues of ddt while it conquered mosquito- borne diseases during wwii and combating world hunger by boosting food production. According to environment canada: 23,000 chemicals were in commercial use in 1986, since then, 800-1000 new chemicals have entered the canadian marketplace each year. A substance"s solubility (ability of a substance to dissolve in a liquid or gas) must be considered when discussing the potential damage to the environment.
