By: Christy Fischer Erin Mascarenas Sadie Yurista.
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Transcript of By: Christy Fischer Erin Mascarenas Sadie Yurista.
By: Christy FischerErin Mascarenas
Sadie Yurista
IntroductionPlastics• have been around since the mid 1800s
• are in everything from cosmetics to medical equipment
• are known to have toxic components such as bisphenol A (BPA) and di(2-ethylhexyl) phthalate (DEHP) that are capable of leaching out
Because plastics are so prevalent in our lives, the environmental and health implications should be further investigated
Take a moment and think…
How many times a day do you, your food, or drink come in
contact with plastics?
1839
Beginning of Plastic Era
Celluloid developed to replace ivory for billiard balls
1863 1872
PVC first created
1908
Cellophane developed
Plasticized PVC (Vinyl)
1926 1953
Saran Wrap introduced
1970
Thermoplastic Polyester (Mylar)
BPA first synthesized
1891
Commonly-Used Plastic Components
BPA and DEHP are found in polyvinyl chloride (PVC) and polycarbonate plastics
BPA is an organic building block of several plastics including type 3 and 7 plastics.
DEHP is a common organic additive used to impart plasticity (fluidity) to materials such as plastic.
BPA and DEHPProduction• BPA is prepared by the condensation of
acetone with phenol, catalyzed by an acid, such as hydrochloric acid.
• DEHP is created by the reaction of phthalic anhydride with 2-ethylhexanol
Other Plasticizers• Though BPA and DEHP have been well-
studied, other plasticizers are now being used
BPA and DEHP UsesBPA has been used in:• Coating of food cans, baby bottles, food
containers, water bottles, dental sealants, toys, makeup, lotion, shampoo
DEHP has been used in:• IV tubing and bags, blood-storage bags,
medical devices, PVC gloves, garden hoses, food packaging, toys, paints, adhesives, floor and wall coverings
BPA ADAMEAbsorption• Ingestion, inhalation, dermal contactDistribution• Depends on point of origin, circulated throughout body by circulatory systemAction• BPA mimics estradiol – endocrine disruptor• Disrupts differentiation of androgen-dependant tissues• Causes failures in cleavage plane determination and
cytokinesis due to disruption of microtubule formation (SEE LINK to sea urchin development, Control (without BPA): http://www.youtube.com/watch?v=nrJcQCTvuh4
with BPA: http://www.youtube.com/watch?v=RJ0uGeMxgX0
• BPA has an oral LD50 of 3250 mg/kg in rats
BPA ADAME (continued)MetabolismBPA has an oral LD50 of 3250 mg/kg in ratsBPA conjugated with glucuronic acid to form
glucuronide Nearly entire oral dose metabolized during
first passExcretionGlucuronide completely excreted via urine
within 24 hours
DEHP ADAMEAbsorptionIngestion, inhalation, dermal contactDistributionDepends on point of origin, circulated
throughout body by circulatory systemActionPeroxisome proliferationInhibits fetal testicular testosterone
production
DEHP ADAME (continued)MetabolismDEHP hydrolyzes to mono-ethylhexyl
phthalate and then to phthalate salts. The released alcohol is susceptible to oxidation to aldehyde and carboxylic acid.
Excretion90% of metabolites excreted in urine10% of metabolites excreted in fecesOne-time dose no longer in plasma after 24
hours, 70% excreted from body by that time
Studies on BPAInduces fibroblast differentiation into adipocytes in
vitroDevelopmental toxicity, carcinogenic effects, and
possible neurotoxicity at low doses in animal modelsLinked to obesity by triggering fat-cell activity and
produces precursors of breast cancerInterferes with chemotherapeutic agents in breast
cancer cellsStudies by the Centers for Disease Control and
Prevention found BPA in the urine of 93% of children and adults tested in 2003–04.
Studies on BPA (continued)Infants fed with liquid formula are among the
most exposed and those fed from polycarbonate bottles can consume up to 13 μg/kg/day of BPA. Some animal studies show effects at much lower doses.
The U.S. Environmental Protection Agency considers exposures up to 50 µg/kg/day to be safe.
Some research methods and funding sources have been criticized: some involved injecting BPA directly into animals and some were funded by plastic manufacturers.
BPA Health ImplicationsLow doses of BPA can mimic the body's
hormones, possibly causing negative health effects. Long term low dose exposure to BPA may induce chronic toxicity in humans.
High BPA levels were significantly associated with heart disease, diabetes, and abnormally high levels of certain liver enzymes.
Can promote breast-cancer cell growthHigh exposure may be associated with recurrent
miscarriage
Control 2.2 µM BPA
Studies on DEHPHepatotoxic at 300 mg/kg in rodents Metabolites produced by soil microbes are
more toxic than the original substanceBrief oral exposure to high levels caused
sperm damage in miceReduces testicular testosterone levels in fetal
and neonatal male ratsHumans may be affected by lower levels than
study animals
DEHP Health ImplicationsDecreased motility of sperm was noted in
men exposed to phthalates
Exposure to phthalates resulted in increased birth weights and longer gestation periods
May be carcinogenic
May be linked to kidney damage
Environmental ImpactsThe abundance of plasticizers has lead to their and the presence of their metabolites in the environment, sometimes in high concentrations
•Many plastics end up in landfills•Degradation/chemical release
-soil micro-organisms degrade plasticizers -these metabolites can be more toxic than original and resist further biodegradation
•Chemicals can seep into water supplies, which effects all biological life to some degree
ConclusionMore studies should be conducted as to the long-
term effects of BPA, DEHP, and other plastic compounds on health and the environment
Avoid microwaving food in plastic containers, putting plastics in the dishwasher, using harsh detergents, and avoid storing containers above room temperature to minimize leaching
Recycling reduces the amount of plastic that the environment is exposed to and protects our water
Refrences Barnabe, S., Beauchesne, I., Cooper, D.G., Nicell, J.A. 2008. Plasticizers and their
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Bellis, M. The history of plastics: time line of plastics. [Internet]. 2009 April [cited 2009 April 25]. Available from http://inventors.about.com/od/pstartinventions/a/plastics.htm
Biello, D. 2008. Plastic (not) fantastic: Food containers leach a potentially harmful chemical. Scientific American. Available from http://www.sciam.com/article.cfm?id=plastic-not-fantastic-with-bisphenol-a
Cao, X., Corriveau, J. 2008. Survey of bisphenol A in bottled water products in Canada. Food Additives and Contaminants: Part B. 1: 161-164.
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