2. WARM-UP
1. Turn in homework
1. Turn in Lab Notebook at the end of the period
2. Put signed papers in PER 1-2 INBOX
2. Take out a scratch sheet of paper and solve the following
3. List out things you consider a toxin. What is not a toxin?
3. Paracelsus, 1493 - 1541
“The right dose differentiates a poison and a remedy”
4. mans. We need to
ose- response
effect (e.g. relieve
ermine how toxic substances are. By exposing
o different concentrationshttp://www.merciasales.co.uk/images/PillsLeft.jpg
of a chemical and
of organisms that die in each, they can generate
ponse
the left.
w toxic substances are. By exposing
t concentrations ofbe a toxin! and
Anything can a chemical
he point on the
e population in each, they can generate
ms that die dies,
sponding LD 50 =
s the LD 50 value 1/ 2 t easpoon
n the
on dies,
impor tant to compare their effect, as
LD 50 =
0 value and 1/ 2 t easpoon right.
of sugar nicotine to the LD 50 = 3 quart s
160 pounds
nt to compare their effect, as
http://www.modernguidetohealth.com/wp-
content/uploads/2009/03/tobacco-nicotine .jpg
http://www.look-good-feel-great-
secrets.com/images/sugar .jpg
ego Pg 2
and nicotine to the right. LD 50 = 3 quart s
5. ns. We need to
ffect (e.g. relieveis LD50?
What
http://www.merciasales.co.uk/images/PillsLeft.jpg
LD 50 (Lethal Dose 50)is the dosage or amount of a chemical
onse that causes 50% of the population react (usually die).
toxic substances are. By experiment testing tobacco gives 10 people ½
For Example: An
exposing
concentrations of a chemical and many people should die if the LD50
a teaspoon of tobacco. How
s that die in each,teaspoon? generate
is ½ a they can
the
dies,
LD 50 =
value 1/ 2 t easpoon
6. -Science in Personal and Social P
How would you find theBackground
LD50 of a
It is impor tant to know toxic
chemical? know how much medicine we can ta
our headache), while not taking too
Toxicologists find the LD50 50% Response Toxico
by performing a test 100 assessm
called dose-response model o
Response (%)
assessments where they obser ving
expose model organisms
to varying concentrations 50 a graph lik
of a chemical.
curve whe
0 we can fin
5 10 15
concentra
Dose (mg/kg) for that ch
Determining these values for
illustrated by the values for a 160-p
7. Another way to measure response to
toxins…
Daphnia heat rate test
8. What kind of toxins can we find in the
water?
http://www.colbertnation.com/the-colbert-report-videos/232640/july-
01-2009/nicholas-kristof
9. Trends in wildlife reproductive health
Figure adapted from Edwards et al. 2006
10. Trends in wildlife reproductive health
Figure adapted from Edwards et al. 2006
11. Trends in wildlife reproductive health
Figure adapted from Edwards et al. 2006
12. Trends in wildlife reproductive health
Figure adapted from Edwards et al. 2006
14. EDCs
Endocrine disrupting compounds
Incidences of altered reproductive health grouped by
geographic area, suggesting an environmental cause
Endocrine disrupting compounds (EDCs)- alter
hormonal and homeostatic systems
15. Endocrine system
System of communication between
tissues via chemical signals (e.g.
hormones) that regulates:
Development
Growth
Metabolism
Reproduction
Calcium regulation
Immune function
Glucose homeostasis
Digestion
Circadian rhythm
Formation of adipose tissue
Diamanti-Kandarakis et al. 2009
16. EDCs- chemical intruders
How can chemicals alter reproductive health?
Endocrine system uses chemical signals
(hormones) - how tissues “talk” to each other
Endocrine system critical for gonad development
and reproductive function
brain gonad
Internal signal
17. EDCs- chemical intruders
How can chemicals alter reproductive health?
Endocrine system uses chemical signals
(hormones) - how tissues “talk” to each other
Endocrine system critical for gonad development
and reproductive function
External signal
18. Limited knowledge about EDCs
How can we identify which chemicals act like hormones?
What are the effects?
What happens when we’re exposed to low-dose
mixtures?
How can we calculate risk?
Where are these compounds found in the environment?
1996 Congress passed legislation to create the EPA
Endocrine Disruptor Screening Program to assess
potential risk to human health and wildlife
19. Health effects on fishes from
urban areas
endocrine disruption endocrine disruption
liver lesions increased risk of disease
cancer damaged nervous system
20. Human diseases linked to EDCs
Development
Growth
Metabolism
Reproduction
Calcium regulation
Immune function
Glucose homeostasis
Digestion
Circadian rhythm
Formation of adipose tissue
Diamanti-Kandarakis et al. 2009
21. Limited knowledge about EDCs
How can we identify which chemicals act like hormones?
What are the effects?
What happens when we’re exposed to low-dose
mixtures?
How can we calculate risk?
Where are these compounds found in the environment?
22. Spices - nautral & human-made chemicals from foods we eat or
plants, e.g. vanilla
Pharmaceuticals - human-made chemicals manufactured for use as
medicinal drugs, e.g. ibuprofen
Plasticizers - human-made chemicals added to plastics to make them
flexible, soft, etc., e.g. dibutyl phthalate (DI-BE-OO-TAHL THAL-ATE)
Industrial solvents - chemicals that are good at dissolving
substances, natural or human-made, e.g. benzaldehyde (BENS-AL-DUH-
HIDE)
Perfumes - a natural or human-made chemicals used to create a nice
smell or mask odors, e.g. linalool (LIN-AH-LEW-AL)
23. EDCs in common household items
Lilial Ibuprofen
Bisphenol A Dibutyl
phthalate
24. Spices - nautral & human-made chemicals from foods we eat or
plants, e.g. vanilla
Pharmaceuticals - human-made chemicals manufactured for use as
medicinal drugs, e.g. ibuprofen
Plasticizers - human-made chemicals added to plastics to make them
flexible, soft, etc., e.g. dibutyl phthalate (DI-BE-OO-TAHL THAL-ATE)
Industrial solvents - chemicals that are good at dissolving
substances, natural or human-made, e.g. benzaldehyde (BENS-AL-DUH-
HIDE)
Perfumes - a natural or human-made chemicals used to create a nice
smell or mask odors, e.g. linalool (LIN-AH-LEW-AL)
31. Your Mission
1. Choose a freshwater water source you are interested in and perform a basic water testing on the
source you collected
2. Choose a toxin you are interested in experimenting with
Types of toxins I have readily available
(http://www.pesticideinfo.org/List_AquireAll.jsp?Rec_Id=PC42993&Taxa_Group=Fish)
Caffeine
Theobromine (chocolate)
Thymol (thyme)
Cinnamic Acid
Cinnamaldehyde
Ethyl Vanillin
Vanillin
Ibuprofen
Detergent and Oil
3. Test the toxin on Daphnia to find the LD50 and a heart rate response
4. Lab Report of Findings, Earth Day and Letter to State Representative
32. What to do Toxins I Have
Get into groups of 2-3 Caffeine
- Think and research about where you want Theobromine
to get water samples from and what toxin (chocolate)
you are interested in testing and why.
Thymol (thyme)
- .Research already known effects of toxin
and save it on a google doc or any file. You Cinnamic Acid
will need it later. Keep a list of sources Cinnamaldehyde
too!!
Ethyl Vanillin
- Tell Quanina when you have decided.
Vanillin
- www.pesticideinfo.org Ibuprofen
Detergent and Oil
33. Before We Begin
Brushing up on metric conversions, dilutions, and pipetting
Unit Conversion
Ladder Method
BS Method
Algebraic Method
Pipetting
How to pipette
A test of your pipetting skills
Concentrations and Dilutions ?
34. Writing your Methods
Needs to be in paragraph form
Can split up the 3 experiments
Water testing
LD 50 or dose-response assessment test
Heart-rate test
Water testing and collecting, be sure to include the latitude and longitude of where you
got the water.
http://itouchmap.com/latlong.html
How much water you got
The depth
Average temperature
What you observed about the water
For actual testing you can write see aqua pharmaceutical master fresh water testing kit for
methods on water testing
35. EMAIL METHODS BY END OF PERIOD
Methods must include…
LD 50 or Dose Response Assessment Test:
How much water you will pour into each jar
Your concentration of toxin in each jar
How many daphnia you put in each jar and how you will transfer the
daphnia
How you will record your quantitative (#) and qualitative (words) data
Demo how to transfer Daphnia
Heart rate test
How you will place the daphnia under the microscope
The concentration of the toxin you will be using
How many daphnia you will be using
How you will record your quantitative (#) and qualitative (words) data
Demo how to take heart rate test
Editor's Notes
1. EDCs are common in products we see and use everyday, including in plastics, costmetics and personal care products. EDCs in common products that end up on or in our bodies include: Lilial – a xenobiotic that smells like lillies of the valley. Very popular in air fresheners and in antistatic sheets for driers.Ibuprofen - a common pharmaceutical used for managing pain and inflammation. Not bad for you in the right doses, but our use of this medicine can be seen in the environment.Bishphenol A (BPA) is a high-profile plasticizer - you can find re-usable water bottles on store shelves that say ‘BPA-free”Dibutyl phthalate is a plasticizer that is a common ingredient in cosmetics and an unlisted ingredient in many fragrancesPhoto: SoundCitizen volunteers collecting a sample
