Advances in environmental hygiene

ADVANCES IN

ENVIRONMENTAL

HYGIENEBy: Abdulrahman Mohammed

(L-2012-V-21-D)

School Of Public Health and Zoonoses, GADVASU, Ludhiana

DEFINITIONSEnvironmental Hygiene: is that branch of public health that is concerned with the control of all those factors in man’s surroundings or physical environment which may have deleterious effect on human health and wellbeing

Alternatively, it could be defined as all those aspects of public health that are determined by physical, chemical, biological, social and psychological factors in the environment.

It also includes theories and practices of assessing, correcting, controlling and preventing the factors present in the environment that can potentially affect the health of present and future generations.

Environmental sanitation: refers to interventions to reduce people’s and animals’ exposure to disease by providing a clean environment in which to live and these measures break the cycle of disease.

Objectives of Environmental

Hygiene

Prevention and control of:

Biological hazards

Chemical hazards

Physical hazards

Sociological hazards and psychological

hazards.

Scope of Environmental Hygiene

Water supply

Waste-water treatment and water pollution control

Solid waste management

Vector control

Prevention and control of soil pollution

Food hygiene

Air pollution control

Radiation pollution control

Noise pollution control

Occupational health

Scope of Environmental Hygiene

cont.…

Housing with particular reference to public health aspects

Urban and regional planning

Environmental health aspects of air, sea or land transport

Accident prevention

Public recreation and tourism

Sanitation measures during epidemics, emergencies, disaster and population migration

Wildlife and forest conservation

Preventive measures to ensure freedom from health risk of the general environment.

Advances in environmental hygiene

includes:

Carbon sequestration

Bioremediation

Rain water harvesting and artificial recharge

Echo-friendly technologies in India

Carbon sequestration

Also known as “carbon capture”

A geoengineering technique for the long-term storage of carbon

dioxide (or other forms of carbon) for the mitigation of global warming

More than 33 billion tons of carbon emissions (annual worldwide)

Ways that carbon can be stored (sequestered):

In plants and soil “terrestrial sequestration” (“carbon sinks”)

Underground “geological sequestration”

Deep in ocean “ocean sequestration”

As a solid material (still in development)

Terrestrial Carbon

Sequestration

Terrestrial Carbon Sequestration

The process through which Co2 from the atmosphere is absorbed naturally through photosynthesis & stored as carbon in biomass & soils.

Tropical deforestation is responsible for 20% of world’s annual Co2

emissions, though offset by uptake of atmospheric Co2 by forests and agriculture.

Ways to reduce greenhouse gases:

avoiding emissions by maintaining existing carbon storage in trees and soils

increasing carbon storage by tree planting or conversion from conventional to conservation tillage practices on agricultural lands

Terrestrial Carbon Sequestration

(continued)

Carbon seq. rates differ based on the species of tree, type of soil, regional climate, topography & management practice

Pine plantations in SE United States can accumulate almost 100 metric tons of carbon per acre after 90 years (~ 1 metric ton : 1 year)

Carbon accumulation eventually reaches saturation point where additional sequestration is no longer possible (when trees reach maturity, or when the organic matter in soils builds back up to original levels before losses occurred)

After saturation, the trees or agricultural practices still need to be sustained to maintain the accumulated carbon and prevent subsequent losses of carbon back to the atmosphere

Geological Sequestration

Storing of CO2

underground in rock

formations able to

retain large amounts of

CO2 over a long time

period

Held in small pore

spaces (have held oil

and nat. gas for millions

of years)

Layers shown: Coal, brine aquifer, gas bearing sandstone, gas bearing shale

Geological Sequestration

(case study)

Midwest Geological Sequestration Consortium (Illinois Basin)

assess geological carbon sequestration options in the 60,000 square mile Illinois Basin (Within the Basin are deep, noneconomic coal resources, numerous mature oil fields and deep saline rock formations with potential to store CO2)

Feb 2009: Successfully completed 8,000 ft deep injection well

By 2013, a total of one million metric tons of carbon dioxide (roughly the annual emissions of 220,000 automobiles) is expected to be stored within the formation.

Ocean Sequestration

Ocean Sequestration

Carbon is naturally stored in the ocean via two pumps, solubility

and biological, and there are analogous man-made methods,

direct injection and ocean fertilization, respectively.

Eventually equilibrium between the ocean and the atmosphere

will be reached with or without human intervention and 80% of

the carbon will remain in the ocean.

The same equilibrium will be reached whether the carbon is

injected into the atmosphere or the ocean. The rational behind

ocean sequestration is simply to speed up the natural process.

Ocean Sequestration

Carbon sequestration by direct injection into the deep ocean involves the capture, separation, transport, and injection of CO2 from land or tankers

1/3 of CO2 emitted a year already enters the ocean

Ocean has 50 times more carbon than the atmosphere

Current Status Carbon

Sequestration

At the global level, the IPCC Third Assessment Report estimates that

~100 billion metric tons of carbon over the next 50 years could be

sequestered through forest preservation, tree planting and improved

agricultural management.

Offset 10-20% of estimated fossil fuel emissions

Carbon Sequestration is not yet viable at a commercial level

Small scale projects demonstrated (lab experiments) but CS is still a

developing technology

Concern with injecting carbon dioxide into ground or ocean

because fear of leaks into water table or escape of CO2 into a massive bubble that can potentially suffocate humans and animals

Bioremediation

Biodegradation - the use of living organisms such as bacteria, fungi, and

plants to degrade chemical compounds

Bioremediation – process of cleaning up environmental sites

contaminated with chemical pollutants by using living organisms to

degrade hazardous materials into less toxic substances

Bioremediation: Purpose

Initiative of the U.S. Environmental Protection Agency (EPA)

To counteract careless and even negligent practices of chemical dumping and storage, as well as concern over how these pollutants might affect human health and the environment

To locate and clean up hazardous waste sites

Bioremediation

Environmental Genome Project

Purpose is to study and understand the impacts of

environmental chemicals on human disease

Why use bioremediation?

Most approaches convert harmful pollutants into

relatively harmless materials such as carbon dioxide,

chloride, water, and simple organic molecules

Processes are generally cleaner

Biotechnological approaches

Biotechnological approaches are essential for

Detecting pollutants

Restoring ecosystems

Learning about conditions that can result in human

diseases

Converting waste products into valuable energy

Bioremediation Basics

What needs to be cleaned up?

Soil, water, air, and sediment

Pollutants enter environment in many different ways

Tanker spill, truck accident, ruptured chemical tank at industrial site, release of pollutants into air

Location of accident, the amount of chemicals released, and the duration of the spill impacts the parts of the environment affected

Bioremediation Basics

9.2 Bioremediation Basics

Chemicals in the Environment

Carcinogens

Mutagens

Cause skin rashes, birth defects

Poison plant and animal life

Fundamentals of Cleanup

Reactions

Microbes convert chemicals into harmless substances

by either

Aerobic metabolism (require oxygen) or anaerobic metabolism (do not require oxygen)

Fundamentals of Cleanup Reactions

Aerobic and

Anaerobic

Biodegradation

Stimulating Bioremediation

Nutrient enrichment (fertilization) – fertilizers are added

to a contaminated environment to stimulate the

growth of indigenous microorganisms that can

degrade pollutants

Bioaugmentation (seeding) –bacteria are added to the

contaminated environment to assist indigenous

microbes with biodegradative processes

Cleanup Sites and Strategies

Soil Cleanup

Ex situ bioremediation

Slurry phase bioremediation

Solid phase bioremediation

Composting

Land farming

Biopiles

In situ bioremediation

Bioventing – pumping either air or hydrogen peroxide into the contaminated soil



Bioremediation of Water

Wastewater treatment

Groundwater cleanup



Applying Genetically Engineered Strains to Clean Up the

Environment

Petroleum-Eating Bacteria

Created in 1970s

Isolated strains of pseudomonas from contaminated

soils

Contained plasmids that encoded genes for breaking

down the pollutants

Applying Genetically Engineered Strains to Clean Up the

Environment

E. coli to clean up heavy metals

Copper, lead, cadmium, chromium, and mercury

Biosensors – bacteria capable of detecting a variety of environmental

pollutants

Genetically Modified Plants and Phytoremediation

Plants that can remove RDX (Research Department Explosive) and TNT

(Trinitrotoluene)

Shrishti Eco-Research Institute, Pune, INDIA

Develops eco-friendly technologies to control pollution of water, air and soil.

Soil Scape Filter

Stream Ecosystem

Hydrasch Succession Pond

Phytofiltration and Biox Process

Green lake technologies

Green bridge technologies

Some of the Ecotechnological installations afre described below

It is the simulation of natural filtration of water or wastewater through the

well developed soils and fragmented rock materials below which give

purified water in the form of groundwater. Soil filter contains layers of bio-

active (i.e. biologically activated) soil.

Soil Scape Filter

It involves the use of the natural slopes of the polluted drains, beds, banks

of streams or ponds to enhance the aerobic activity in water by

generating turbulence and providing shallow depths to allow sun– light to

reach the bottom

Stream Ecosystem

It is an application of ecological succession of aquatic plants depending on characteristics of incoming effluents. Various green plants including invasive species are successfully employed in these phytofiltration and phytoremediation processes with ecoremediation to treat organic and inorganic pollution.

Hydrasch Succession Pond

It involves the use of plant fibres, roots to remove suspended solids from

wastewater effectively in well designed tank.

Some of the installations are solids by biosorption methods

Phytofiltration and Biox Process

uses floating, submerged or food web help in the

purification process. These can be termed as

macrophyte ponds also .

Macrophytes are capable to absorb large amounts

of inorganic nutrients such as N and P, and heavy

metals such as Cd, Cu, Hg Zn etc and to engineer the

growth of microbes to facilitate the degradation of

organic matter and toxicants.

Green lake technologies

Green bridge technologies

uses filtration power of biologically originated cellulosic / fibrous material in combination with sand and gravels and root systems of green plants.

Ecotechnological Applications for the Control of Pollution in India

Efficacy of Green Bridge and Green

Lake treatment systems

RAIN WATER HARVESTING (RWH)

RWH refers to collection and storage of rainwater and also other activity such as harvesting surface water extracting ground water , prevention of loss through evaporation and seepage.

PURPOSES OF RWH

Stored for ready use in containersground or below ground

Charged into the ground for withdrawal later

BENEFITS OF RWH

Rainwater harvesting prevents flooding of lowlying areas

Rain water harvesting replenishes the ground water table and enables our dug wells and bore wells to yield in a sustained manner

It helps in the availability of clean water by reducing the salinity and the presence of iron salts.

RHH TECHNIQUES

STORAGE OF RAINWATER ON SURFACE FOR FUTURE USE

RECHARGE TO GROUND WATER

1. SUBSURFACE DAMS

2. CHECK DAMS

3. ROOF TOP CATCHMENTS

4. FARM PONDS

RECHARGE TO GROUND WATER

Recharge bore pit

Recharge well

Spreading basins

Ditches

Hand pumps

RECHARGE BORE PIT

RECHARGE WELL

DITCHES

HAND PUMPS

SPREADING BASINS

References

Sengupta, M. and Dalwani, R. (Editors). 2008. Ecotechnological Applications for the Control of Lake Pollution. Proceedings of Taal 2007: The 12th World Lake Conference: 864-867

Sherikar A.T, Bachhil V.N and Thaplyal D.C. 2001.Textbook of elements of veterinary public health. ICAR, New Delhi.

Chu,S.C and Liaw,C.H 1995-1997 study of industrial rainwater catchment systems(I)-(III). Final Report of Indus. Tech.Res.Inst

Liaw,S.C and Tsai,Y.L.2002. Application of rainwater retardation and retention for a healthy water envirnoment in urban areas.Journal of water resources management

Liaw,C.H., Chen,H.K, Chang, K.c. and Tsai, Y.l. 2000. Feasibility analysis of rainwater catchment systems in taiwan,proc. East Asia 2000 Rainwater utilization symposium:131-144, oct.1,2000,Taipei,Taiwan.

http://en.wikipedia.org/wiki/Carbon_sequestration

http://www.netl.doe.gov/technologies/carbon_seq/index.html

http://www.princeton.edu/~chm333/2002/fall/co_two/oceans/

http://en.wikipedia.org/wiki/Carbon_sequestration

http://www.netl.doe.gov/technologies/carbon_seq/index.html

http://www.princeton.edu/~chm333/2002/fall/co_two/oceans/

THINK GREENTHANK YOU FOR LISTENING