Download MBBS (Bachelor of Medicine, Bachelor of Surgery) 1st year (First Year) Biochemistry ppt lectures Topic 43 Environmental Biochemistry Notes. - biochemistry notes pdf, biochemistry mbbs 1st year notes pdf, biochemistry mbbs notes pdf, biochemistry lecture notes, paramedical biochemistry notes, medical biochemistry pdf, biochemistry lecture notes 2022 ppt, biochemistry pdf.
Environmental Biochemistry
Health and Il -Health Effects Of
Unpol uted and Pol uted Environment
Do's and Don'ts To Maintain
Clean and Green Environment
Contents
? What is an Environment?
? Significance of an Environment on
Human Health
? Environmental Pol ution and Pol utants :
Types, Sources, Effects on human health
Control and Prevention
What Is An Environment ?
Features Of An Environment
? Next to Nutrition, Environment is most important
factor for human healthy life
? Environment is purely a natural entity where
human being in his living is surrounded with it.
? Environment of human being comprises of :
Atmosphere,air,water,soil,radiations,sound
,Temperature etc.
? Environment is directly and indirectly connected to
human body
? Natural environment is balanced and healthy
Environmental Entities
? Atmosphere
? Water
General
? physical structure
Oceans
? chemical composition
? composition, desalination
Outer Atmosphere
? ozone - photochem,
Fresh water
Troposphere
? Sulfur, acid rain
? Oxygen, water treatment
? CO
? NOx, smog
? "Green Chemistry"
? CO2, H2O
? Climate
Human Beings Leaders Of Universe
are Responsible For Maintaining State
Of An Environment
Significance Of An Environment On
Human Health
Close Relationship Of
Environment And Human Health
Environmental Pol utants
Environmental Pol utants Directly
Affect Human Health
Toxicity Of Pol utants Depends Upon
Amount,Duration,Potency
? Toxicity of pollutants is measured by dose and
response
? Dose: An amount that enters body of an exposed
organism
? Response: An amount of damage caused by a
specific dose
? LD50
? Lethal dose to 50% of test organisms
? Smaller LD50 more lethal is the chemical
? Determined for all new synthetic chemicals
Toxicity
? ED50
? Effective dose to 50% of test organisms
? ED50 causes 50% of population to exhibit whatever
effect is under study
? Dose-Response Curve
? Illustrates an effect of different doses on a
population
? Threshold Level
? Maximum dose with no measurable effects
Environmental Pol utants and Disease
? Often difficult to
link pollutants to
their effects on
people
? Persistence
? Bioaccumulation
? Biomagnification
Persistence
? A characteristic of certain chemicals that are
extremely stable and may take many years to
be broken down into simpler forms by natural
processes
? Synthetic chemicals (those not found in nature)
? Ex: DDT
? Natural decomposers (bacteria) have not
evolved a way to break it down
Bioaccumulation
? Buildup of a persistent toxic substance in an
organism's body, often in fatty tissues
? Synthetic chemical do not metabolize well
? They remain in body for extended periods of time
Biomagnification
? An increased
concentration of
toxic chemicals in
tissues of organisms
that are at higher
levels in food webs
? Diagram is example
of biomagnification
of DDT
Groupings of Chemical Pol utants:
Grouping
Grouped According to:
EDC (Endocrine Disrupting Chemical)
toxicological mode of action or
CMR (Carcinogenic, Mutagenic, toxic to
endpoint
Reproduction)
PBT (Persistent, Bioaccumulative Toxic)
environmental properties
vPvB (very Persistent, very Bioaccumulative)
POP (Persistent Organic Pollutant)
PPCPs
type of intended usage
priority pollutants and others
legislation
"emerging" contaminants/pollutants
novelty, fad, timeliness, or new
concern
PPCPs as Environmental Pol utants
? PPCPs are a diverse group of chemicals comprising all human and
veterinary drugs (available by prescription or over-the-counter;
including new genre of "biologics"
? Diagnostic agents (X-ray contrast media)
? Nutraceuticals (bioactive food supplements such as huperzine A)
? Fragrances,Perfumes,Deos Sprays (e.g., musks)
? Sun-screen agents (e.g., 4-methylbenzylidene camphor
octocrylene)
? Excipients (so called "inert" ingredients used in PPCP
manufacturing and formulation; e.g., parabens)
Mechanism of
Environmental Pol utants
? Environmental pol utant of physical, chemical or
biological origin
? Interacts with various biomolecules of human body
as per specific affinity
? Accumulate in cel s and tissues
? Disturb biomolecule structural features
? Distract biomolecules from true function
? Loads immune system, liver and kidneys
? Alter normal health
? Leads to il -effects/disorders- Anemia,Cancers
Endocrine Disrupters
? A chemical that mimics or interferes with the actions of
the endocrine system in humans and wildlife
? i.e. It effects the ability of the hormones in the organisms to
function properly
? Examples include:
? PCBs, Dioxins
? Heavy metals ? lead and mercury
? DDT
? Animals exposed to these chemicals have altered
reproductive development and are often sterile
Endocrine Disrupters and Humans
? Infertility and hormonally related cancers are
increasing
? Breast cancer and testicular cancer
? Phthalates have been implicated as potential
endocrine disrupters
? Common ingredient in: cosmetics, fragrances, nail
polish, medication, toys, food packaging
? Cannot make a link between endocrine
disrupters and human illness
? Too few studies have been performed
Determining Health Effects of Pol utants
? Toxicants to human body
? Toxicant- chemical with adverse human health
effects
? Acute toxicity
? Adverse effects occur within a short period after
exposure to toxin
? Chronic toxicity
? Adverse effects occur some time after exposure,
or after prolonged exposure to toxin
? Symptoms often mimic other diseases- hard to
assess source
Children and Chemical Exposure
? Children are more susceptible to chemicals
? Weigh less than adults
? Bodies are stil developing
? Play on floors and lawns
? Exposed to cleaning products and pesticides
? Put things into their mouths
Exposure Of Chemical Mixtures
? Generally humans body is exposed to chemical
mixtures
? Ex: automobile exhaust
? Chemical Mixtures interact by
? Additivity
? Synergy
? Antagonism
Risk Assessment
? Risk- probability that a particular adverse effect wil
result from some exposure or condition
? We assess risk daily with four steps:
1. Hazard identification
2. Dose response assessment
3. Exposure assessment
4. Risk characterization
Environmental Hazards
Composition of Atmosphere
? Composition of gases in
an atmosphere is not
uniform.
? Lighter gases tend to rise
to top.
Gases are measured in ppm volume (?L/L), which is
directly proportional to mole fraction.
Outer Atmosphere
? Sun emits radiation
across an
electromagnetic
o
f
p
h
o
t
o
n
s
spectrum.
umber
? Light in an ultraviolet
N
region has enough
energy to break
chemical bonds.
Wavelength, m
Energy
Ozone
? Ozone absorbs much of radiation between 240 and 310
nm.
? It forms from reaction of molecular oxygen with an oxygen
atoms produced in upper atmosphere by
photodissociation (< 242 nm).
O + O2 O3
Ozone Depletion
In 1974 Rowland and Molina (Nobel Prize, 1995)
discovered that chlorine from chlorofluorocarbons
(CFCs) may be depleting the supply of ozone in the
upper atmosphere.
Troposphere
Although Troposphere is made up almost entirely of
nitrogen and oxygen, other gases present in relatively small
amounts still have a profound effect on troposphere.
Radiation
Aurora
Formed {Atmosphere is first
here
line of defense against
radiation from Sun.
Chlorofluorocarbons
CFCs were used for years as aerosol
propellants and refrigerants.
Mostly = CFCl3, CF2Cl2.
They are not water soluble (so they do not
get washed out of the atmosphere by rain)
and are quite unreactive (so they are not
degraded naturally).
Water Vapor and Carbon Dioxide
? Gases in an atmosphere form an insulating blanket that
causes the Earth's thermal consistency.
? Two of the most important such gases are carbon
dioxide and water vapor.
Water Vapor and Carbon Dioxide
? This blanketing effect is
known as the "greenhouse
effect."
? Water vapor, with its high
specific heat, is a major
factor in this moderating
effect.
? But increasing levels of CO2
in an atmosphere is causing
an increase in global
temperatures.
Sulfur
? Sulfur dioxide is a by-product of burning of coal or oil.
? It reacts with moisture in air to form sulfuric acid.
? It is primarily responsible for acid rain.
Carbon Monoxide
? Carbon monoxide binds
preferentially to the iron
in red blood cells.
? Exposure to CO can
lower O2 levels to the
point of causing loss of
consciousness and death.
Nitrogen Oxides
? What we recognize as
smog, that brownish gas
that hangs above large
cities like Los Angeles, is
primarily nitrogen
dioxide, NO2.
? It forms from the
oxidation of nitric oxide,
NO, a component of car
exhaust.
Photochemical Smog
Smog also contains ozone, carbon monoxide,
hydrocarbons, and particles.
Effect of Photochemical Smog on
Human Health
Effects Of Water Pol ution
Shocking side effects of Earphones
To Brain and Ears!
? TINNITUS. [Noise in ear]. . .
? HYPERACUSIS. This is an increased sensitivity to
normal environment sounds.
? SEVERE EAR INFECTION. It is usual y unavoidable
that people share earphones. . .
? LOSS OF HEARING. . .
? AFFECTS YOUR BRAIN. . .
? EAR PAIN. . .
? LOSS OF CONNECTION WITH REALITY. . .
? LEARNING DISABILITIES.
Research findings
Sound's volume by 6 to 9 decibels
? Loud music played on earphones causes hearing
loss by having a similar effect on nerves as
multiple sclerosis,
? Research shows noise levels above 110 decibels
strip insulation from nerve fibers carrying signals
from the ear to the brain.
Human Responsibilities To Maintain
Healthy Environment
? Use Sense, time and Energy for Significance and
Health
? Be Monitor,maintainer,Constructor
? Never be Destructor
? Do sensible environmental friendly acts which
control and prevent pollution
Factors For Quality Of Health
? Intentions and Actions= Behavior (Sleep Cycle)
? Nutrition (Food Cycle)
? Environment
This post was last modified on 05 April 2022