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Enst 403/Envr 403: Spring 2009. Tues, Thurs room 11AM-12:15AM Location: Dey Hall room 201 Call number 36019 , Section 001 http://www.unc.edu/courses/2009fall/enst/403/001/ Richard Kamens; 966 5452 kamens@unc.edu http://airsite.unc.edu/~kamens/. Textbook

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enst 403 envr 403 spring 2009
Enst 403/Envr 403:Spring 2009
  • Tues, Thurs room 11AM-12:15AM
  • Location: Dey Hall room 201

Call number 36019, Section 001

  • http://www.unc.edu/courses/2009fall/enst/403/001/
  • Richard Kamens; 966 5452
  • kamens@unc.edu
  • http://airsite.unc.edu/~kamens/
slide2
Textbook
  • "Environmental Chemistry by Colin Beard and Michael Cann, ISBN 0-7167-4877-0, publishers W.H. Freeman and Company, New York, 652 pages, 2005
who is richard kamens
Who is Richard Kamens
  • Professor of Atmospheric chemistry and teach graduate classes in Environmental chemistry
  • Direct a smog chamber research gorup
  • Focus on aerosol formation in the atmosphere
  • Direct a student exchange program between UNC and Thai Universities
slide5
On smoggy days in LA, Atlanta, Beijing and other major cities ~50 - 80% of FINE particle organic carbon comes from atmospheric reactions.
  • Atmospherically aged aerosols appear to be more toxic than freshly emitted particles.
  • A strong need for predictive aerosol models that can simulate complex atmospheric processing?
link the phases that toxics exist in

Thermodynamic Equilibrium

Cgas +surf Cpart

Temperature

Chemical nature of gas

Humidity

and particle

Link the phases that toxics exist in

Trace toxic gas

particle

predict organic particle formation in the presence of complex urban atmospheres

O3

NO

NO2

NOy

Predict organic particle formation in the presence of complex urban atmospheres

25

20

15

3

g/m

m

8:00

10:24

12:48

15:12

17:36

slide10

Aerosol Model and data from particles generated from aromatics and O3 and NOx in sunlight

1ppmC o-xylene

1ppmC toluene

field site director for a unc thai exchange
Field site director for a UNC-Thai exchange
  • Since 2001, UNC undergraduates (CEP)participated in a 6+ month experience in Thailand that begins at the end of May and finishes in late December.
  • Small groups of UNC students come together with Thai students to study and work on a research project at Thai universities.
  • Thai students come back with UNC students for a semester at UNC.
impact of bio fuels use on photochemical smog
Impact of Bio-fuels Use on Photochemical Smog
  • The widespread use of gasohol and bio-diesel in Bangkok will most likely lead to an increase in ground level ozone.
  • Bio-fuel use will benefit the Thai economy.
  • Bio-fuels can supply at most 10% of the Thai petroleum needs.
introduction to environmental chemistry
Introduction to Environmental Chemistry
  • Environmental chemistry may be defined as "the study of sources, reactions, transport, effects, and fates of chemical species in water, soil, and air environments, and the effects of technology thereon.” Manahan, 1994
class objectives
Class objectives:
  • Highlight some important areas in environmental chemistry
  • present some of the common techniques that environmental chemists use to quantify process that occur in the environment
  • It is assumed that everyone has courses in calculus and general chemistry.
class objectives1
Class objectives:
  • We will cover general topics: Global warming, Strat. O3, aerosols, photochemical smog, acid rain, etc.
  • Develop relationships will be used to help quantify equilibrium and kinetic processes
thermodynamics
Thermodynamics
  • ui = uo1 +RT ln pi/p*iL
  • fi = i Xipi*pure liquid
  • RT lnfi hx /fiopure liq = RT lnfi H2O/fiopure liqfihx = fi H2O
  • ln Kp = a 1/T+b
vapor pressure
Vapor pressure

How to calculate boiling points

vapor pressure and henry s law
Vapor pressure and Henry’s law

sat

P

sat

sat

*

i

K

P

V

iL

iw

sat

iaw

iw

C

iw

Solubility and activity coefficients

Octanol-water partitioning coefficients

additional principles
Additional Principles
  • Organic Acid-bases and LFERs
  • diffusion
  • chemical spills and mass transfer
  • Organic reactions in the environment
  • Solid- liquid interactions
  • photochemistry
homework quizzes exams
Homework, quizzes, exams
  • To insure that most of us stay reasonably current with the lectures and readings, an option is to have 8-10 unannounced quizzes throughout the semester.
  • They will take ~10 minutes. Quizzes will count 10% of your grade.
slide24
Another option is a set of short questions to be answered and handed in before most lectures (20% of your grade)—your choice!
slide25
There will be a homework problem set associated with each lecture. These are due one week after the completion of the chapter or lecture series.
  • These problem sets should take between 1 and 3 hrs.
important environmental issues
Important Environmental Issues
  • Global warming and stratospheric ozone depletion
  • Concentration of environmental pollutants at the poles; pesticides in foods, etc.
  • Buildup of environmental chemicals in the oceans; contamination of soil and ground water
  • Particle exposure, photochemical oxidant exposure, acid deposition
  • Energy shortages
slide28

Why the interest?

There are more than 70,000 100, 000 synthetic chemicals that are in daily use:

solvents

components of detergents

dyes and varnishes

additives in plastics and textiles

chemicals used for construction

antifouling agents

herbicides, insecticides,fungicides

pharmaceuticals

polynuclear aromatic hc pahs dioxins pcbs cfcs ddt o 3 no 2 aerosols so 2

Some examples of environmental chemicals

Polynuclear Aromatic HC (PAHs)

Dioxins

PCBs

CFCs

DDT

O3, NO2, aerosols, SO2

slide30

PAHs

Formed from small ethylene radicals “building blocks” produced when carbon based fuels are burned

Sources are all types of burning

in ChiangMai, Thailand:a) 2-stroke motorcycle engines b) cars- light diesels c) open burning d) barbecued meat??

combustion formation of pah
Combustion Formation of PAH

Badger and Spotswood 1960

some pah structures
Some PAH structures

fluoranthene

naphthalene

anthracene

benz(a)anthracene

phenanthrene

benzo(a)pyrene [BaP]

slide33

PAHs

Naphthalene, phenanthrene and anthracene are found in the gas phase

pyrene and fluoranthene are in both the gas and particle phase

BaA and BaP are mostly on the particles, Why???

slide34

PAHs

Metabolized to epoxides which are carcinogenic; O PAH

are indirect acting mutagens in bacterial mutagenicity tests (Ames-TA98+s9)

methyl PAHs are often more biologically active than PAHs

slide35

Carcinogenic tests with PAHs

Professor Gernot Grimmer extracted different types of smoke particles

He then took the extract and applied it to mouse skin

and implanted it into rat lungs

How did he obtain extracts?

How did he fractionate his extracts??

slide38
The solvent in the filter chamber then drains back into the heated flask withchemicalsfrom the particleson the filter

Heat

slide39
The organic liquid in the soxhlet flask can be concentrated by evaporation by a dry nitrogen stream or rotary evaporation
  • the extract can then be fractionated into different polarity compound groups
professor grimmer fractionated the exhaust extracts
Professor Grimmer fractionated the exhaust extracts

HPLC

uv orfluorescencedetector

Total

Total

PAH 2&3 rings

PAHs>3 rings

Total-PAHs

what did grimmer see when exposed rats and mice to the different fractions
What did Grimmer see when exposed rats and mice to the different fractions?
  • skin painted mice
  • implanted rat lungs
analysis of reaction products
Analysis of reaction products
  • soxhlet extraction for 3 hours
    • blow up with dry gentle flow of nitrogen to about 0.5 to 1 ml
  • evaporation to about 0.5 to 1 ml
  • 1 to 2 ul injected directly to GC-MS (EI and CI)
  • The remainder solution: derivatization
slide44

Chlorinated dibenzo dioxins and Furans

These are some of the most toxic organics in the environment - LD50

Created by burning organics which have chlorine; incineration is a big source of atmospheric dioxins and furans

bleaching in making paper is another source

combustion formation of dioxins from polychlorinated phenol
Combustion Formation of Dioxins from Polychlorinated phenol

O

H

Clx

.

OH

Clx

Flame

.

O

O

H

+

Polychlorinated

Phenol

C

l

y

O

+ OH

O

Cly

Cly

Clx

O

Clx

O

H

Chlorinated dibenzo dioxin

Shaub & Tsang, ES&T 1983.

slide47

Cl

x

Cl

y

They have the following general structures

O

Cl

x

O

Cl

y

chlorinated dioxin

O

chlorinated furan

the most toxic is either the 2 3 7 8 tetrachlorodibeno dioxin or furan

O

Cl

Cl

Cl

Cl

O

More than 200 different structures are possible

The most toxic is either the 2,3,7,8 tetrachlorodibeno dioxin or furan

slide49

These types of compounds produce toxic enzymes: arylhydrocarbon hydroxylase and 7-ethoxyresorufin deethylase

At low concentrations they may behave as environmental estrogens

slide50

Environmentally, they are unreactive and can be transported long distances

They did not start to show up in the environment until the 1920s when there was a big increase in the production of chloro-organics (Professor Ron Hites, and students)

environmental fate of chlorinated dioxins and furans czuczwa and hites 1984
Environmental Fate of Chlorinated Dioxins and Furans(Czuczwa and Hites, 1984)
  • Collected core sediment samples from southern Lake Huron in the USA
  • Based on sedimentation rates they established age vs. concentration profiles for chlorinated dioxins and furans
pcbs in the u s great lakes
PCBs in the U.S. Great Lakes
  • PCBs were banned in the early 1970s
  • In 1980 Eisenreich and co-workers estimated that still 85% of the PCBs in the US great lakes came from atmospheric sources.
polychlorinated biphenyls pcbs
Polychlorinated biphenyls (PCBs)
  • Total Flux = Jair + Jrain + Jparticles
  • Jair = vw ( Cw-P/KH)if resistance to mass transfer is in the water phase
  • Jair = va (Cw KH - P)/RT if resistance is in the gas phase
slide56

In the late 1980s a fugacity model was used to represent the distribution of PCBs in different environmental compartments

  • RT lnfair /fiopure liquid = RT lnf H2O/fiopure liquid
  • fair= f H2O
slide57
In 1990 Eisenreich and co-workers reported that ambient measurements over the great lakes were generally constant for the past 10 years.
  • For the past 15 years sources to the lakes had declined because of the PCB ban.
  • Based on mass transfer calculations it was proposed that during the summer months the lakes were actually a source of atmospheric PCBs.
slide58

Polychlorinated biphenyls (PCBs)

used as coolants - insulation fluids in transformers, capacitors , plastercisers, additives to epoxy paints

are thermally stable and biologically stable

can exist in the gas and particle phases

slide59

Cl

x

Cl

y

PCB structures

  • Environmentally, they used to be considered unreactive, but there is evidence for some bio-degradation; they can be transported long distances
slide60

Up until the 1970s there was a lot of dumping of industrial wastes in the USA

In one example, from 1950 to 1975 there were two capacitor manufacturing plants on the Hudson river in New York State, which discharged into the river.

slide61

Levels in the river sediments downstream from the plants exhibited concentrations of 10 ppm which was a factor of two higher than commonly found.

Dredging was considered financially impossible

it was also believed that is very difficult to bio-degrade PCBs with multiple chlorine atoms

slide62

Investigations in the 1980s revealed that PCBs in sediments were being slowly converted to the mono and dichloro forms via very slow anaerobic processes.

{CH2O} + H2O + 2Cl-PCB---> CO2 +2H++ 2Cl-- +2H-PCB

what do we do now when new compounds are introduced into the environment
What do we do now, when new compounds are introduced into the environment...??
  • toxicity??
  • low concentration health effects?
  • damage to the ecosystem ?
  • where will it show up in the environment?
  • how is it transported in the environment and what is its life-time?
slide64

Some examples of environmental exposures

In 1976 there was a significant industrial explosion in the town of Seveso, Italy that spewed out chlorinated dioxins.

735 people were evacuated from the immediate vicinity.

Now excess cancers are showing up.

seveso italy dioxin release
Seveso, Italy Dioxin release
  • Over the past eight years the birth ratio has changed from 106 males: 100 females to 26:48
  • observed increases in cancers
  • decline in number of males born
a similar observation has been made in the bird population
A similar observation has been made in the bird population
  • In the Great Lake region of the USA during the 1980’s, hatchlings of crested cormorants with a crossed bill deformity were almost always female
  • Male birds did not show the deformity
  • Scientist speculate that the chemicals causing the deformity were killing the males before they hatched.
slide67
1. There is a general concern that if we observe abnormalities in wildlife, similar kinds of mechanisms may exist in humans.
mercury poisoning off the coast of minamata japan is an example
Mercury poisoning off the coast of Minamata, Japan is an example
  • Fishermen in the 1950s noticed sea birds were dying and feral cats that scavenged fish from the docks were “stiff legged”
  • Cerebral palsy and mental retardation started showing up in children.
2 toxic loads
2. Toxic loads
  • Scientists have hypothesized that the fetus is sharing the mother’s toxic load, and may actually provide some protection to the mother by reducing her internal exposure.
2 toxic loads1
2. Toxic loads
  • Children get 12% of their lifetime exposure to dioxins during the 1st year.
  • Their exposure is 50 times greater than an adult during a very critical developmental period.
2 toxic loads2
2. Toxic loads
  • Firstborns from dolphins off the coast of Florida usually die before they separate from their mothers
2 toxic loads3
2. Toxic loads
  • It is speculated that mother dolphins unload 80% of their accumulated pollutants into their calves, probably during nursing.
  • The greatest exposures occurs with the 1st born
  • Does this have any implications for humans?
3 pesticide exposures
3. Pesticide exposures
  • Children of farm families in the western Minnesota area of the US have significantly higher rates of birth defects than the general population.
  • The highest rates are among children conceived in the spring when spraying of pesticides is most intense; male babies had far more birth defects than females
4 the end points may not only be cancer but compromised immune systems and generally poorer health
4. The end points may not only be cancer, but compromised immune systems and generally poorer health.
4 immune systems mother s milk
4. Immune systems & Mother’s milk
  • In the Netherlands researchers have found that children with higher levels of dioxins and PCBs in their bodies have more health problems (immune system and hormonal changes) than children with lower levels.
  • This was linked to levels of PCBs in Mother’s milk.
4 mother s milk
4. Mother’s milk
  • Overall, however, it was concluded that nursing was still of greater benefit than bottle feeding babies, but that even mild exposures may weaken immunity
4 mother s milk1
4. Mother’s milk
  • Mother’s milk from Inuit Indians in the Canadian Arctic has 7 times the PCBs as mother’s milk from women in the urban industrialized areas of southern Quebec.
4 mother s milk2
4. Mother’s milk
  • During the first year, Inuit babies suffer through 20 times more colds than babies in southern Quebec.
  • Acute ear infections are rampant.
4 mother s milk3
4. Mother’s milk
  • Babies nursed by mothers with the highest contamination levels in their milk are afflicted with more acute ear infections than bottle fed Inuit babies.
  • Many of these children don’t seem to produce enough antibodies for childhood vaccinations to take.
5 pcbs and lower intelligence
5. PCBs and lower intelligence
  • There is evidence of lower intelligence in babies exposed to PCBs.
  • In adults, a blood-brain barrier insulates the brain from many potentially harmful chemicals circulating through the body
  • In a human child this barrier is not fully developed until 6 months after birth.
5 pcbs and lower intelligence1
5. PCBs and lower intelligence
  • In 1979 in Taiwan, more than 2000 people were exposed to PCB-contaminated cooking oil.
  • In the 1st 3 months many babies died outright. As the surviving children grew up, many were slower intellectually than other kids their age, were hyperactive and had behavioral problems.
5 pcbs and lower intelligence2
5. PCBs and lower intelligence
  • Similar observations were made in "high-PCB kids" in the Lake Michigan area.
  • This was associated with mothers eating salmon and trout from the Lake during the years before their children were born.
5 pcbs and lower intelligence3
5. PCBs and lower intelligence
  • At age 4 the high exposure group had poor short term memories. At age 11 the 30 most highly exposed kids had average IQ scores that were 6 points lower than the lowest-exposed group.
  • biomarker-metabolites???
7 sexual impairment
7. Sexual impairment
  • There is evidence for sexual impairment in both animals and humans from high PCB exposures and other environmental chemicals.
  • Male beluga whales in the very polluted St. Lawrence River have exhibited female organs.
7 sexual impairment1
7. Sexual impairment
  • Highly exposed humans, alligators and panthers exhibit smaller male sex organs and low sperm counts.
  • Testicular cancers have nearly doubled among older teenagers in the US between 1973 and 1992.
  • In previous lectures I have said these have been linked to toxic exposures....long way from finding proof.
7a sexual impairment
7a. Sexual impairment
  • In a newer study (Hardwell et al, Environ Presp, 2003) looked at woman who’ve had substantial exposure to certain environmental pollutants are more likely to have sons who develop testicular cancers (men ~ 30 years of age)
  • From 1973-1999 testicular cancers up 67%
  • Men with test-cancers had high cis nona chloridane, not PCBs, etc
  • Mothers, however, had high PCBs, HCB (hexa-chlorobenzenes) and cis nona chloridane
7b sexual impairment
7b. Sexual impairment
  • These same mothers probably had high exposures when environmental contaminants peaked in Scandinavia in the 1970s
  • Richard Sharpe of Edinburogh and Niels Skakkebek (Denmark) propose that exposure to endocrine disruptors before birth can alter testicular-cell development and some of these cells may be cancerous after puberty.
  • This may also may explain rising rates of male infertility, and other sexual deformities
8 endocrine disrupters
8. Endocrine disrupters
  • These studies have led to the notion of environmental "endocrine disrupters".
  • In the lock and key relationship between hormone and receptor molecules, these "hormone impostors" can:
8 endocrine disrupters1
8. Endocrine disrupters
  • bind with receptors and trigger biological processes
  • or bind with receptors and tie up an active hormone site
  • Some of these have been called environmental estrogens
9 other chemicals
9. Other chemicals
  • From a historical perspective, everyone is now carrying at last 250 measurable chemicals that were not part of human chemistry before the 1920s (Peter Myers, 1996)
  • The most basic toxicity testing results cannot be found in the public record for nearly 75% of the top volume chemicals in commercial use in the USA
9 other chemicals1
9. Other chemicals
  • In other words, the public cannot tell whether a large majority of the highest-use chemicals in the United States pose health hazards or not (Amicus Journal, p23, Spring 1998).
  • An example are phthalates that go into many types of plastics which have been shown to reduce the sperm counts in mice.
9 other chemicals2
9. Other chemicals
  • Bisphenol-A (BPA) is an additive in polycarbonate plastics used in food liners, dental sealants, and dental fillings.
  • BPA causes increased prostate size in mice exposed to tiny doses while in the womb. These doses were 25,000 times smaller than the EPA threshold.
9 phthalates
9. Phthalates
  • Exposure of female rates to 200 to 1000 mg/kg body weight results in much lower testosterone in male offspring( L. Earl Gray. Jr. EPA, RTP, J. Tox and Ind. Health, Mar, 1999).
  • Exposures to the herbicide linuron made the epididymis (sperm-storing organ in rats) much smaller in male rats.
recommendations
Recommendations
  • During the insecticide spraying season, farmers should not try to have children.
  • Limit exposures to pesticides around the home.
  • When possible, buy foods that were grown without pesticides.
  • Governments must try to limit PCB introduction into the environment.
  • If incineration is used, chlorinated plastics should be removed, along with modern technology.