Aquatic Pollution & Health Risks

CVL100: Environmental Science - Water Pollution Overview

• Prof. Sovik Das from the Department of Civil Engineering at IIT Delhi teaches the Environmental Science course, CVL100.
• Contact Prof. Das at [email protected]; his office is Block-V, Room No.-305.
• The course will explore water pollution.

What is Pollution?

• Water pollution occurs when water's physical, chemical, or biological characteristics are altered through natural or human activities.
• The water becomes unsuitable for its designated use.

Water pollution

• During the Middle Ages, diseases such as cholera and typhoid fever broke out across Europe, related to unsanitary conditions
• By the 1800s, unsanitary living conditions and water contamination were understood to contribute to disease epidemics.
• Chicago built the first major sewage system in the United States in the mid-1850s to treat wastewater.
• The World Economic Forum has identified water scarcity as one of the major global risks.
• Globally, two-thirds of the world's population live in areas facing water scarcity for at least one month a year.
• About, 50% of this population lives in China and India.
• In India, only 37% of wastewater produced gets treated.
• More than half of the Indian cities fall under water stress regions.

Sustainable Development Goals (SDG)

• SDG 6 focuses on clean water and sanitation.
• Target 6.1: Achieve universal and equitable access to safe and affordable drinking water for all.
• Target 6.2: Achieve access to adequate and equitable sanitation and hygiene for all and end open defecation.
• Special attention is paid to the needing women and girls, and others in vulnerable situations.
• Target 6.3: Improve water quality by reducing pollution, eliminating dumping and minimizing the release of hazardous chemicals/materials.
• Halve the proportion of untreated wastewater, and substantially increase recycling/safe reuse globally.
• Target 6.6: Protect and restore water-related ecosystems like mountains, forests, wetlands, rivers, aquifers, and lakes.
• Water quality is addressed under other SDGs (health, poverty reduction, ecosystems, and sustainable consumption/production).
• Water should be linked to the key environmental, socioeconomic, and development issues (Goals 1, 3, 12, 15 and Targets 1.4, 3.3, 3.9, 12.4, 15.1).

Baseline water stress

• India was thirteenth among the world's 17 "extremely water-stressed" countries in 2019.
• This is according to the Aqueduct Water Risk Atlas, released by the World Resources Institute (WRI).
• Orange and dark-orange areas on the map are highly or extremely highly water-stressed.
• More than 40% of the annually available surface water is use each year.
• In rural India as of 2009, a significant number of habitations faced water quality challenges.

Water pollution in India

• 1 billion liters of raw, untreated sewage gets dumped in the Ganga regularly.
• The Ganga has more than 60,000 fecal coliform bacteria per 100ml, which is a threat to human health.
• Ganga is considered the most polluted river.
• 57% of Delhi's waste is thrown into the Yamuna.
• Only 55% of Delhi's residents are connected to a proper sewerage system.
• Around 80% of Yamuna's pollution is due to raw sewage.

Sources of water pollution

• A point source is a single, identifiable source of pollution, such as a pipe or a drain.
• Industrial wastes are commonly discharged to rivers and seas in this way.
• Example includes pipes attached to factories, effluents coming out from industries, oil spills from tankers.
• Non-point source pollution source is not known or pollution does not come from a single discrete source.
• Difficult to control, may come from different sources like pesticides, fertilizers, industrial wastes etc.

Types of water pollution

• Surface Water Pollution: Can occurs in 3 ways:
• Naturally: flooding or tsunamis can pick up fertilizers, pesticides, debris, and other contaminants.
• Accidentally: From oil spills and runoff of agriculture.
• Intentionally: This is done when industries dump waste directly into waterways.
• Groundwater Pollution: A key source is agriculture; fertilizers/pesticides applied to farmland absorbed into the ground/transported as runoff.
• Landfills and septic systems can contaminate it when waste leaches into the ground. Thermal Pollution: Reduces the capacity of water to hold dissolved oxygen (DO).
• As the temperature of water rises, the level of DO decreases.
• Increases the rate of metabolism in fish and damages larvae/eggs.
• Main source of thermal pollution comes from plants discharging cooling water into rivers.

###Causes of Water Pollution

• Agricultural Runoff
• Sources include farmland Irrigation events, Rainfall Events, Livestock Operations, Overland Flow.
• How it causes water pollution:
• Runoff carries nitrogen and phosphorus from fertilizers, leading to nutrient pollution.
• Rain and irrigation water can transport pesticides/herbicides into rivers/lakes, impacting aquatic ecosystems.
• Water erodes exposed soil from farming, carrying sediment, and runoff from areas containing livestock can contribute to pathogens.
• Industrial Discharge: Sources of pollution include:
• Liquid waste discharged directly.
• Rainwater carrying pollutants from industrial areas into nearby rivers/streams that cause unintended releases of chemicals or pollutants.
• Deforestation is an indirect cause of water pollution
• Soil erosion and runoff of chemicals and nutrients that are released into the water sources.
• It also leads to the loss of riparian zones and banks, as well as altered Water Flow with increased contamination risk.
• Municipal Sewage discharges:
  • Effluents released from sewage treatment facilities into water bodies
  • Discharges occurring during heavy rainfall when rainwater carries the waste of pollutants to the water sources
  • Leaks, breaks blocks and/ or blockages in municipal sewer lines that carry pollutants to water sources
• Oil Spills:
  • Causes include shipping accidents, offshore drilling, pipeline ruptures, well blowouts, natural seepage, industrial activities, and more.
  • They release toxic substances, such as polycyclic aromatic hydrocarbons (PAHs), harming aquatic life and contaiminating water.
  • It affects breathing and feeding and microbes consume oxygen from the water.
  • Reaching beaches and shores, affects coastal ecoystem

Atmospheric deposition

• Airborne pollutants released by industries that settle on water surfaces.
• Pollutants from vehicle emissions and transported pesticides and fertilizers transported settling into rivers and lakes.

Environmental impacts

• Bioaccumulation and biomagnification - refers to the concentration of chemicals within an organism that disrupts the food chain.
• Leads to loss of habitat, biodiversity, and effects on aquatic life.

Effects on aquatic life

• High levels of pollution decline or extinct various aquatic species, disrupting the balance of ecosystems.
• Organic matter and nutrients stimulate growth of microorganisms, leadin to increased microbial activity that consumes oxygen ( "dead zones" where aquatic life cannot survive).
• Toxic chemicals, heavy metals, or nutrients can lead to fish kills and affecting the food chain.
• Heavy metals and pollutants can accumulate in tissues, gradually reaching higher concentrations as they move up the food chain (risks to predators, including humans).
• Sedimentation and general pollution can degrade aquatic habitats, affecting reproduction and survival of various species and can alter reproductive patterns.

Effects on aqaatic life, continued

• Exposure can cause genetic mutations in organisms.
• Changes in nutrient levels and pollutants can disrupt the web of relationships within ecosystems, and pollutants can hinder the growth of aquatic organisms.
• Altered behavior in aquatic species, can affecting feeding and migration patters, and overall ecosystem dynamics.

Human health implications

• Chemicals in water affecting health include:
  • Heavy metals such as Fluoride, Arsenic, Lead, Cadmium, Mercury, petrochemicals, chlorinated solvents, pesticides, and nitrates.
• Fluoride, below 0.5mg/L causes dental carries and mottling of teeth, higher than 1mg/L can lead to fluorosis.
• Arsenic contaminates water through tanneries, insecticide, ceramic and chemical factories.
  • Arsenic can cause bladder and lung cancer as well as respiratory cancer, plus arsenic skin lesions.
• Lead contaminates drinking water from household plumbing systems, which affects the central nervous system, plus blood and kidneys.
  • Children and pregnant women are more prone to lead exposure.
• Mercury contaminates through smelters and manufacturers (batteries, thermometers, pesticides, fungicides, etc)
• Minamata disease is caused by eating fish containing methyl mercury.
• Contaimnation can cause chromosomal changes/neurological damage and biological magnification in aquatic ecosystems.

Water-related diseases

• Water-borne diseases resulting from ingestion include gastroenteritis, hepatitis, cholera, dysentery, leptospirosis, poliomyelitis, and typhoid/paratyphoid fever.
• Water-washed diseases result from skin, ear, or eye contact that include conjuctivitis trachoma and helminth infections.
• Diseases due to inhalation of pathogens include legionellosis and phiesteria.
• Water-based disease from worm infection that involves the parasites with schistosomiasis and bilharziasis.
• Insect vectors breeding in/near insect borne pathogens that include dengue, lymphatic filariasis, malaria, onchocerciacis, trypanosomiasis and yellow fever.
• Death rates due to unsafe water sources were gathered for 2019.
• Globally 2 billion people lack safe drinking water of which nearly 300,000 are children under 5 dying annually from disease (diarrhea).

Monitoring and Measurement

• Growth of water polution in India was updated as of CPCB of 2009.

Water Quality Parameters

• Indicates how clean/polluted the sample of water is
• The three types include physical, chemical and biological
• Physical: Turbidity, Solid content, Temperature, Conductivity and Color
• Chemical: pH, Alkalinity, Hardness, Nutrients and Dissolved Ions
• Biological: Virus, Protozoa, Bacteria and Helminths

Solids

• Solids can be retained by a filter paper and pass through a filter.
• It can be suspended, colloidal or dissolved.
• Suspended solids µm size ranges from 1 to 100.
• Colloidal solid µm size ranges to the 10^-3 power.
• Dissolved solid µm size ranges to the 10^-5 to 10^-3 power.

Turbidity

• Measure of the extent to which light is adsorbed or scattered by suspended material.
• Indirect measure of solids in water
• Mostly due to colloidal particles in surface waters
• Commonly used in water treatment plants (WTP) to measure quality of potable water.
• Expressed as NTU (Nephelometry turbidity unit).

Alkalinity

• It represents the water's ability to neutralize acids.
• Most common constituents are hydroxide, carbonate, bicarbonate.
• It is pH dependent and is used as a process control variable in wastewater treatment.

pH

• The measure of how acidic (low pH value) or basic (high pH value) is alkaline the water is.
• The term pH comes from the French: "puissance d'Hydrogène", meaning the strength of the hydrogen.
• It is defined as the negative log of the hydrogen concentration and this goes from 0 until the number of 14.
• The scale is logarithmic and for each whole number increase (1 -> 2) the hydrogen ion concentration decreases ten fold and the water becomes less acidic
• Many reactions inside aquatic organisms and growth require a narrow of pH

Hardness

• Defined as the concentration of multivalent metallic cations in solution.
• In natural waters, hardness is caused by magnesium and calcium ions.
• It can be classified as either carbonate and noncarbonate hardness depending on its association with the amount of anion with which it associates.
• Carbonate hardness precipitates readily during water treatment and carbonate hardness is an equivalent to alkalinity.
• It can be measured through titration.

Conductivity

• Represents the ability of a solution to carry an electoral current- and increases in direct relation to the concentration of ions present.
• The current can be carried by sodium, magnesium, potassium, calcium, chloride, and more nitrates, sulfates, and phosphates.
• The conductivity can be used to estimate the TDS value of water

###Nutrients

• Nitrogen and Phosphorus serve as limiting nutrients for aquatic plant life
• High amounts in surface water can lead to eutrophication.
• Large nitrate content can result in methemolobinemia/blue baby syndrome

Pathogens

• The organisms involved that transmit or infect diseases to humans are bacteria, helminths, protazo, and viruses.
• Bacteria Salmonella typhi, Vibrio cholerae, Shigella dysenteriae
• Viruses include polio and hepatitis.
• A protozoa is amoebic dysentery.
• Most critical test for drinking water quality

Organic Content Estimation

• It has to be analyzed in the laboratory by Chemical and Biochemical Oxygen Demand (COD & BOD).
• In addition of total Organic Carbon (TOC)
• TOC analyzer uses high temperature (720°C max) in addition to an oxidation chamber for conversion in addition to a sensor
• Carbon dioxide generated by oxidation is measured with a sensor.

Biochemical Oxygen Demand (BOD)

• Quantity of oxygen required for matter present in the water under aerobic conditions.
• Test premise is that biodegradable and organic matter will be oxidized to carbon dioxde/water. Is by microrganisms that use molecular oxygen.
• BOD is going to yield lower compared to other methods of estimating ox demand, in part because new bacterial cells synthesized carbon.
• Reaction continues when there is DO, when it is anaerobic conditions take place.
• A typical polluted water value is that of 0.23 per day and K (base 10, 20°C) is 0.10 per day. A wide variety range, including waste water, will be 0.05-0.3.10-7.0,

BOD Profile

• Ultimate oxygen exerted is the max, it has an infinite achievement time.
• When that part of horizon has been achieve is when most of the bod is over.
• T BOD is going to take chemical/chemical process to take part of
• It doesn't indicate however the oxygen will deplete if there be receiving of water.

Formula for BOD estimation

• The test bottle with seeded dilution water is to have it's DO level drop by 1.0 mg/L in a 5-day incubation. A 300 milliliter BOD filled with 10 millimeter of waste water and the rest seeded dilution water experiences 6.2 mg/L. In the same time period determine the five-day sample for the waste water is the solution here (BODt=((DOi-DOf)-(DOi seed-DOfseed)(Vol seed/Vol sample))/DOi-DOf

Temperature Correction

• The biochemical reactions are temperature dependent and the microorganism activity are determined.
• Temperature affects all oxygen consumption to the rates utilization that affect it.
• The standard temperature which it's to be is 20°C
• Water temperature is place to place with different factors.

Temperatures

• A sewage solution incubated for one day at 30°C has the been found to be 100 mg/L. Assume K = 0.12 (base 10) at 20°C, and θ = 1.056
• L = 10/1-e-0.12= 834
• K 30c = 0.12*(1.028)10C= 0.186
• BOD = 83.4 (1-e-0.1125*2.3)-=68.18 mg/L

Chemical Oxygen Demand (COD)

• This test includes to determine of the oxygen requirement of the waste water, and is only the strong oxidizing agent 'potassium dichromate' is to be used. Acidic environment accelerates with the addition of sulfuric acid/test reflux is used and the heat goes until 150 C.
• With catalyst silver recovery, organic compounds that have a percent greater by a percent of 92 get measure and virtually are all oxidizable whether biodegradable or not, and some compounds can resist the oxidation.
• The code proportional in BOD are readly used in matter from dissolved form.

COD Cont

• No correlation between BOD and COD unless sample should be present in the form.
• It's tested with the ratio of being dairy with 0.92 is an equivalent form.
• However, there should also be necessary to evaluate and test that of long time.
• So all routine control will be available for longer periods.

Theoretical oxygen demand (ThOD)

• The theoretical oxygen demand for the wastewater is calculated as oxygen required for oxidizing the organic matter to end products.
• For example, for glucose, the theoretical oxygen demand can be worked out as below (C6H12O6 + 6O2 →6CO2 + 6H2O). Most of ThOD are equivalent to the COD.

Self Purification of Natural Streams

• Self purification of natural water systems is a complex process with chemical, biological, and physical parameters
• Commonly-used indicator of a rivers health relies on the amount of Dissolved Oxygen (DO )
• The lower the dissolved oxygen, the lower forms of life that can survive.
• A minimum do of about 2mg/L is required to maintain higher life forms.
• Remove do; plants add it by respiration of oxygen.
• Rising temperature reduces oxygen, while lower flows lower oxygen from the atmosphere.

Factors affecting self-purification

• Temperature
• Dilution
• Sunlight and other environmental factors
• Rates of Oxidation and Depletion

Oxygen Sag Curve

• Oxygen sag or oxygen deficit can be analyzed by time of purification based on content of DO.
• DO depends on the temperature and salts present.
• When initial BOD load occurs with the current, the oxygen start depleting and oxygen increases.
• The variation of oxygen can effect a river/stream; max deflection or point.

Rate of reoxygenation

• Lower velocity of current for stagnant bodies of water
• Oxygen deficit below saturation
• Water based on solubility of temp, saturations decrease/lower
• Oxygen reoxygenation in shallow depth.

Streeter – Phelps Analysis

• The rate of oxygen can be assessed by suggesting that a graph and test by deoxygenation. K, t and B all to do factors on the oxygen deficit The deficit value helps to analyze any pollutants.

Greenhouse Gases/Global Warming

• Global warming refers to the increase of average global temperature.
• Extensive investigations are being done on global warming and issues are still controversial.
• Solar energy reaches earth as a visible light portion gets absorbed, a larger of the radiant energy has longer wave lengths and is re trapped.
• Some of the gases that assist in doing the above effects are as follows CO2, CH4, N2O, CFCs, and H2O Vapor
• The green house effect is essential to have for existing for supporting life on the earth,
• Earth temperature would be -21 °C but now it is 14 °C

###Atmosphere/Global Warming

• Air consists of different gases, for example
• In the presence of CO2 it may not be available.
• The increase in CO2 since has caused problems. -The earth increase .3 to .6 annually
  • End of the century may increase 2.5 degrees. In India we can see a big change.

###Global Warming + Effects

• The effect could very unpredictable such as: - Red tides, increases water submergence, water, etc.
• This in turn causes problems by a rise global sea level.
• Warming can not occur fast enough to be dissolved in the water.

Effects of Climate Change

• The hydrological cycles can easily affect as they contribute towards the 70% of water on Earth
• Heavy rain and drought can be results which we may not be prepared or know.

Co2

• The use and production of plants and photosynthesis (C3/C4). Is not to a certain degree affected. The pest are another problem as well as well the global warming.

###Culprits of Global Warming

• CO2 and some greenhouse gases have different quantities.
• CO2 has enormous release such as thermal combustion, auto, biomass, and anaerobic.
• All which contribute, the list can go on, though.

GWP Units

• Carbon dioxide emissions for each ton
• This gives an estimate of each molecule.

Co2 Continued

• Co2 continues its problems since industrial, pre etc/all continues to affect.

Mitigation Measures

• The earth in 99 in the city is the year to prevent carbon from green affects.
• Nations have agreed to give financial incentives to countries to lower .
  • The US was not in full acceptance in certain treaties

Japan and Carbon Credit

• In order to fix, there have to be financial funds and economic support from wealthy countries or high carbon emitters. Carbon credits can be the solution to reduce carbon emissions. That countries can have the credits to lower it to 5.
• Currently the largest concern relates to CO2.

GHGs

• Global monthly/yearly and estimates of the million is needed to be shown in the graph, so governments know where to change.

• Sweden and others can give example in efforts to reduce, etc -Reforestation -Reducing non fossil fuels -Converting disposal practices - Proper cultural -Looping combustion -Carbon use

###CO Sequestration

• As a result of human, nature cannot correct in enough time.

• A CCS (Carbon Capture storage) device is a source

    -From at the point of extraction
    -Removing 
  

CCS

• Store underground
• inject it into oceans, or convert is needed in the environment
• Vegetation and soil can act as carbon units.
• There are different means of storage geological -Used wells - Unmineable coal

Ocean Sequestration

• Injection and increase, as one or stimulation or increase in phytoplankton and decrease in atmosphere.
• Looping combustion

###CLC

• Oxygen has much fuel to burn, with CO2, etc.

###Lopping

• This happens with metal oxcides, oxygen transfer to fuel is to be used, but air from contact is no more. -Only water from combustion.

• There, costs and separated materials have to go. -Pure CO2 collect, inject into mines, time has passed. -The CLC can take action, to all, with reactions at hand.

• There's no 271 which the space is in.

###Space Issues -Earth is not alone, in the way has to be a different sphere. -Space is adding debris and pollution, but rocks, cosmic rays, etc.

###Space Debris -Rockets, spent, all have pieces. -There a dangerous level of waste, and sizes and dimensions are the problems. -They can act as shrapnel - The objects act to collide

What to do With Space Junk?

-IADC. Can fix

• It can be detected

  • It does not have the time and it’s to crowded. So there
  • Many proposals interdiction-reidirection.

###Ocean Debris

• It will get very bad and they may turn to earth and explode

      +Solar collectors
      +Collision
  

• Nuclear explosions -There many be small asteroids or debris which can be used for that. Interdiction and reaction must take care of.

More Threats in Space

The Gamma Rays are as follow, -If you were to get hit by, there a danger - If you were to were in the way.

• Solar flares can disrupts communications on the surface.

Pollution from the Space

Oceans, all affect and draw -There so much about it we don't Know and what there is to affect.

• A 20 feet ocean, there is a heavy one as that is the same volume with 5x less than air
• But more, movement is affected and a much worse is water, that effect is still to be know at more. - They take an enormous amount of resources. -They follow temperature and salinity. Which if all gets messed up -Elino there a huge problem

Marine Concerns

    -Oceans that create carbon over geological.
    -A lot that's happening is out control
    -There much need of materials such the food

Algal Bloom

-Algal Blooms and warmer waters cause a huge problem for the ocean.

• The blooms can also block oxygen that comes to hurt more, there something that more can not be for in order fix this issue. 80
• It causes problems, but can come and it can clear. Also chemicals can add in there.

Solutions

Oil Continued

• Burning can cause harm, sinking to and from are a harm.

Conclusion

• The future and the current, is in the mix, but we should take it seriously to make sure we don't have a future problem

Macro

Ozone, there a lot which a big problem,

-With those two men investigating and showing that this is.
- Our atomosphere can fix only up to a certain extent where after we are done

Ozone

It a important thing for is to not have because of uv -Can do more that one thin such it may also not be good for something Distribution- all is what is up in there. Can be destroyed with chlorine that can be regenerate

• It can effect poles, and it can effect radiation

History of Chemicals in the Air

We have found out that it doesn't work, although it was a good fix in the way was now doing

• Chemical have changed that fix

-With 3 layers in the sky, uv can only have so much to be blocked Fixing must can effect as 3oo mg It will have to be no ODS to go all the way. Altenantives exist, some exist that they all have global and long year

More on That

Releasing can find. But then be a more to the environment then all this which can have harm. -They are a series of events. They cause a series of problems

-This must end soon when the ODS goes and with it we shall see that of in our future.

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