Environmental Final pt.1 (Bio-4850)

Hereditary effects of radiation

effects which do not become apparent until further generations are born

Somatic effects of radiation

effects experienced by people directly exposed to radiation

• raditation may make a mutation (cause cancer)

Ionizing Radiation in Proliferating cells

1. DNA damage

2. Inability to replicate

3. cell death

Ionizing Radiation in nonproliferating cells

• lipid peroxidation of membrane phospholipids

• loss of membrane integrity

Primary peroxidation products

they wont be able to make the membrane

Secondary perioxidation products

complete cleavege of primary products

Three Mile Island (1979)

• Meltdown of reactor 3 failed effort to clear water air line, it overheated and radioisotopes were released

• mainly xenon and krypton

• took a long time to find

• microsoft just bought it to fix and restart it

Chernobyl

• 200 times the radiation unleashed by the atomic bomb blasts in Hiroshima and Nagasaki combined

• epidemic of thyroid cancer among children in Belarus and Ukraine

• cause birth defects in tons of children since 1986

• up to 150,000 deaths as direct result of the catastrophe

• russians died trying to invade through during the war

Fukushima Daiichi nuclear disaster

• earthquake and automatic shutdown, tsunami disabled generators, operating cooling pumps

• One confirmed death and 1500 long-term effects

Radium Watch Dial Painters (1940’s and 1950’s)

many died from making the watchs because they had such high exposure for so long

risk of ionizing radiation

• There is no threshold dose

• 25% of people currently develop fatal cancer, this increases by 4% when using nuclear energy

unit of radiation

Sievert

Radon

• based on different geographical places

• important to have good

• Schools are often checked

effects of radiation in ecology

• The Oak Ridge bomb factory released isotopes into the water

• studys were shown in mosquitofish

radon in mosquitofish

it was shown that the exposure changed the lengths of DNA, more total strand breakages but less double strand breakage

• This also increased genetic diversity by the amount of mutations

nuclear power gen I

early prototype reactors

• shipping ports

• Dresden

• magnox

nuclear power gen II

commercial power reactors

• LWR-PWR, BWR

• CANDU

• WER/RBMK

nuclear power gen III

Advanced LWR’s

• ABWR

• System 80+

• AP600

• EPR

nuclear power gen IV

no later than 2030, significant advances in sustainability, safety and reliability, and economics

• can now use nuclear waste as power

CANDU

• canadian pressurized deuterium reactor

• designed in 1950’S and still used today

• 6 units were built, now 31 and 18 are running

• uses enriched uranium

SMR

• smaller more compact, designed to be pre-fabricated elsewhere and moved

• generate 300MW of power

• go longer without refueling

• less power grid requirements

Resurgence of nuclear energy

• electrification demands are currently logistically different

• AI and data center requirement increase power need by 30% in 2030

• wind and solar are not reliable

• only viable carbon neutral option

Structure of HAH

they are all the same and changed by adding between 1 and 8 chlorine atoms. But there cannot be a chlorine at the alpha carbon

PCBs

specifically manufactured due to their dielectric heat stability and fire retardant properties

• estimated that 1.5 million tonnes were produced, 65% in land fills, 31% in environment, 4% has been incinerated

• name depends on how long you cook it for

• the degree of chlorination is controlled by contact time of reactants

Dioxins

• incineration of municipal solid waste

• production of copper and steel

• combustion of any organic material

• accidental burning of PCB laden electrical equipment

• chlorine bleaching of paper products

TCDD

the most potent HAH

• LC50 of 0.001mg/kg

Ah receptor of AhR

• a ligand-activated transcription factor involved in the regulation of several genes, including those for metabolizing enzymes such as cyp450 1A and 1B

• the Ahr and ARNT dimerize and are involved in transcription regulatory proteins

genes regulated by the Ah receptor

• CYP1A1

• CYP1A2

• CYP1B1

• glutathione s-transerase Ya

• mostly CYP genes

exposure of chlorinated dioxin

• contamination of vietnam soldiers with agent orange

• dioxin cloud escapes after an explosion at Philips-Duphar. It killed 4 people and 50 others suffered from the exposure. this plant produced 2250 tonnes of agent orange

• large amounts of dioxin was released in a industrial accident at seveso

• dioxin was one of the contaminants that forces the evacuation of the love canal in niagra falls, New York

• exacuation of times beach, missouri

• parts of Czechoslovakia were contaminated by them, which flushed from a factory into a Labe river during the 2002 european flood

• Belgium, entered the food chain through contaminated feed

• clinical changes in woman who had high contamination in their bodies

Dioxin Poisoning in a Ukranian Politician

exposed to the second-largest measured dose of dioxins, this was the first known case of single high dose TCDD poisoning.

Dioxin Poisoning

• gives the worst ever case of acne

• doesnt normally kill people

• induces depression and suicide

• was given to people in the KGB (only pure poison)

• in anything we eat but it not carcigenic

PCB contamination

• Yusho oil diease

• contaminated rice oil poisoning

• contains PCDF as trace compounds

• associateed with low birth weight

• great lakes are highly contaminated

Yu-Cheng syndrome

low birth weight due to PCB contamination

fish and wildlife impacts of HAH

• herring gulls showed particularly high dioxin levels and lack of reproduction is related to behaviour

• showed colder air = less parental care

fish in the great lakes

• dioxins/PCBs suspected to cause the collapse of the populations

• very potent to trout

• decrease in size due to: overfishing, lamprey, and other compounds

Trichlosan

• a HAH that breaks down faster

• used as a disinfectant

PFO’s

hugh domestic useage for flourinated surfactants (used in carpets).

• 37% used in surface treatment

• 42% on paper products

• and other used in fire foams

• in all drinking water and now in polar bears

Narcotic

agent that numbs, named by the greek physician Galen.

• DOES NOT MEAN A DRUG

Narcosis

term used by Hippocrates for the process of benumbing or the benumbed state

• gives a generalized depression in biological activity in the presence of toxicant molecules

Nitrous oxide

used as laughing gas in the dentist office

Narcosis observations

1. reversible when exposure to the narcotic is removed

2. reversible by high pressure

3. potency related to lipophilicity

their action was related to the partiction coefficient between water and olive oil, used on fish to see they stop swimming

Meyer-Overton rule

potency of a narcotic is related to lipid solubility, expressed as [ED50]xP=a, where a = concentration and P=partition coefficient.

• pressures of 150atm can restore consciousness to an anesthetized animal and has been central to several theories

critical volume hypothysis

narcosis occurs when the membrane volume is increased to by the narcotic to a critical level

Lipid bilayer fluidity

Narcotics alter lipid bilayer fluidity. Through unlikely due to high dose required and opposite from expected effects of temperature

Phase transition

Narcotics alter the transition from gel to liquid crystal phase. all narcotics have a different Tm

membrane changes from narcotics

small but can be permenant at clinic doses, also to proteins

Anesthetics with globular proteins

interact like they most likely have molecular targets at clinically relevant concentrations are ionchannel receptors.

• many volatile anesthetics modulate GABAA receptors. however the group of inhaled anesthetics mainlu influence function of postsynaptic glutamate NMDA receptors instead

exceptions to the meyer-overton rule

non immobilizers (support protein model). these may allow gases to bind to cytosolic globular proteins but not to ion channel receptors, which possess smaller hydrophobic cavities, thereby producing moderate neuronal dysfunction.

they cannot cross the membrane and can be chiral (left or right handed)

Thermodynamics theory to narcosis

showed is can be reversed by any mechanism that raises the transition temperature and restores the free energy difference to its original value. recognize its crazt becuase of how dominant the ion channel picture

Coordination Chemistry

based on a metal’s tendency to seek oxygen or nitrogen/sulphur groups for bonding

• offer a basis upon which the behaviour of metals in biological systems can be predicted

Metals and metalloids

• occur naturally and are considered contaminants upon mobilization and modification by human activities

• involves changing form and/or location

• 90% of contaminated places are from metals

Copper mining

we now need to mine double the amount that has ever been mined in total before, we need it but its also toxic

biological metals

function as cofactors

iron cofactor

constituent of hemoglobin

magnesium cofactor

constituent of chlorophyll

essential elements

• zinc

• iron

• maganese

• copper

• flourine

• molybdenum

Non-essential elements

• cadmium

• nickel

• lead

• aluminum

• colbalt

• arsenic

dissolved metals

• free cations and anions, biologically available

• hydroxy-ions

• complexed with organic ligands

not dissolved metals

• complexed with inorganic ligands

• forma flocculent

• absrbed to colloidal particles

monovalent cations

remain as ions over natural pH ranges in freshwater

divalent cations

form hydroxy-complexes in basic waters

trivalent cations

form hydroxy-complexes at natural pH ranges

pH effects of hydrolysis

makes toxic metals non toxic when the acidity goes to basic conditions (aluminum is most complex)

hardness

refers to the concentration of divalent ions Ca and Mg in terms of CaCO3 equivalents

hardness effects on toxicity

• reduces metal toxicity

• WQC for some metals is adjusted for hardness

• care must be taken to tease out effects of pH/alkalinity from hardness

Dissolved Organic Carbon

• metals like Cu form soluable inorganic and organic complexes with many substances (95% of dissolved Cu can be bound by organic carbon)

• natural DOC occurs as fulvic and humic acids, which have many functional groups

Effects of DOC on toxicity

ameliorates toxicity through formation of less bioavailable metal-organic carbon complexes (carbon gives water the brown colour)

Free Ion Activity Model (FIAM)

• the model states that the free ion is the best predictor of metal bioavailability

• the cells negatively charged sites are veiws as a ligand where free metal binds

• the free ion interacts with the cell surface and is transported into the cell

Biotic Lagnad Model

shows toxicity in cupric, cadmium, and copper. A middle of the other two models

Mercury

• outbreak of poisoning in Japan (1950) from a chemical plant

• human poisoning in iraq following consumption of Hg-treated grain

• light bulbs had enough to kill a child

• pollution from chlor-alkali plants in canada and sweden

• high in aboriginal people due to hydroelectric reservoirs

• flooded areas give bacteria a lot of it to break down into the food web

• loons in Keji have a high concentration of it

elemental mercury

volatile, scarcely soluable in water

Divalent inorganic mercury

sparsely soluable, associates readily with particles and water

methyl mercury

most important organic form of Hg

main source of mercury

coal

toxicity of Hg

• methyl Hg is of greatest concern

  • behaves like an organic contaminant and moves across the membrane

• most available and toxic form

• neurotoxicant in mammals

• affects several systems at higher concentrations

• the actual biochemical mechanisms of toxic actions

• lower forms of life are less susceptible to Hg poisoning

lead occurrence and sources

• Pb occurs naturally in small amounts. Exists in a valence of 2 and 4

• anti-knocking in car engines

Mobilization of lead

• weathering, volcanic activity

• 5th most common metal in the world

Transport of Pb

• The atmosphere is a major Pb transport vector

• inorganic Pb in particulates travels varying distance depending on particle size

• transport also depend on winds and precipitation

Behaviour of Pb

• limited chemical changes occur to Pb upon deposition from the atmosphere

• majority of the Pb in the environments is from atmosphere

• doesnt bioaccumulate

• accumulates in setetives

Pb exposure to other biota

• bad in water to plants, and fish

• highest exposure from ingestion of contaminated objects

• toxic effects to aquatic biota is unlikely except if high exposure occurs in soft waters at low pH

• benthic organisms accumulate high levels with no adverse effects

Toxicity of Pb

• multisystem toxicant, mostly connects to CNS

• inhibits hemoglobin and RBC synthesis

Copper

• exists in trace amounts in the environment

copper mobilization

• extraction of Cu from its ore

• agriculture

• wasta disposal

• CuSO4 makes the water blue

Sources of copper

• soils are usually contaminated by atmoshpere, fungicides, and sewage sludge

• aquatic systems receive Cu from same + algicides

• Cu is a fungicide allowable for organic farming, used on the island

Environmental chemistry (Copper)

• its solubility depends on pH

• it forms strong complexes with organic ligands in water, sediments and soil

Physiology of copper

• essentail trace nutrient in all living organisms (cofactor in >30 enzymes)

• it is also toxic, therefore regulated by all organisms

• biological effects of Cu conform to FIAM

toxicity of copper

• kidney and liver in mammals make it non-toxic, with low bioavailability in food

• soil microbial activity makes terrestrial systems a bit susceptible

• aquatic animals are 10-100x more susceptible

• mainly found as fractions with sulphide

Cadmium occurence and sources

• rare trace metal common by mining and smelting

• released from coal combustion, refuse incineration, steel manufacture, and cigarettes

• used in Ni-Cd batteries, pigments, and manufacture of plastics

• ~7000 metric tonnes released annually into the environment

Properties of Cd

• only 2+ state is reflected in its compounds

• Cd has no physiological function

• Bioavailability is best predicted by free Cd ion activity

Cd toxicity in humans

• category 1 carcinogen: respiratory exposure linked to lung and prostate cancer

• most serious case was Itai-Itai disease

• most Cd accumulates in kidney and liver

pH of acid rain

any precipitation with a pH of 5.62 at 1 atm

Sulfer and nitric oxides

produced by burning of organic material or mining/melting. much from making steel (16% of all greenhouse gases)

where does 5% of all world green houses gases come from

the superstack in sudbury, Ontario

where is most of canada’s energy from

60% of it is from Hydro

how are acids formed

through gas phase chemistry, and liquid phase chemistry

Sulfur

a major component of acid rain

• 80% from fossil fuel burning and industrial activity

• the other from natural fires and volcanoes

• having it in the air corrods metals

Nitrogen

the most critical species in air pollution

Robert Smith

noted acid rain in 1852 (before the concept of pH), this was ignored until 1981

• silent spring book catalyzed the research

• several feilds began to study acid rain

Gorham (1954-1961)

a series of papers on the modern foundations of acid rain

• more acid rain near industrial regions

• this can increase acidity of bog waters

• this then goes into the soil

• it can be linked to bronchitis in humans

• metal smelters deteriorate the environment around it

• showed effects on crops in 1940 sweden

• evolved to european air chemistry

energy to acid rain

in china is showed that coal was the main source of energy and that they often get more acid rain