Part 2 Flashcards
Identify the primary waste emitted by the pulp and paper industry
bleaching and finishing processes,
sludge from wastewater treatment, and
air emissions from combustion of fossil fuels and biomass.
Describe the general process of how the pulp and paper industry operates
. Bark is separated from the rest of the wood
2. Production of pulp
3. Treatment of pulp to give paper qualities
4. Pulp goes into a paper machine where it is formed into paper and dried
There are two ways to produce pulp
− The Sulfite Process
− The Sulfate/Kraft Process
More BOD : Sulfite
Acidic = sulfite
Greater variety of wood types= sulfate
water treatment for pulp and paper pollutants
pre-treatment, primary treatment, secondary treatment, tertiary treatment
Tertiary treatment:
further reduce BOD and SS, lower toxicity, and mitigate color, odor, and taste problems
How to reduce the toxic chemical in industrial effluents ( Solution )
Remove the toxic chemical from manufacturing process
Recover and recycle the toxicants before discharge
Remove toxicant from wastewater and dispose of it an environmentally friendly manner
2 processes that influence oxygen levels
Respiration of microbes that consume organics matter in the wastewater ( decreasing oxygen saturation%)
Reaeration of water with oxygen from atmosphere ( increasing oxygen saturation %)
What would the conditions of the wastewater to be in order to create such a curve
Wastewater high in organisms that consume oxygen
Organic matter that is food decomposers
Define pesticides
kill or control insects, or other unwanted organisms
Classification of Pesticides ( Target species ) Herbicides
designed to kill plant growth
Selective herbicides kill only one type of plant
Non-selective herbicides kill all plants
Fungicide
designed to kill fungi growth
Insecticide
designed to kill insect
Chemical nature
(i) Chlorinated Organics
chemically stable and can accumulate in fatty tissues, leading to bioaccumulation and biomagnification
Some chlorinated organics like DDT are highly toxic to fish and birds
DDE, DDD, and methoxychlor are alternatives to DDT
Chlordane, heptachlor, aldrin, and dieldrin have been banned due to their carcinogenic
Chemical nature
(ii) Organophosphates
They are less stable, do not bioaccumulate/biomagnify as readily
classified as the most toxic of all pesticides to most animals, including humans
Examples of organophosphates are malathion and parathion
Malathion is less toxic to humans and can be found in garden store pesticides
Parathion is highly toxic to humans and has caused most of the human pesticide poisonings worldwide due to improper use
Chemical nature
(iii) Carbamates
They are all derivatives of carbamic acid
they don’t bioaccumulate/biomagnify
not very toxic to fish but are highly toxic to birds and bees
Two common carbamates are aldicarb and carbofuran
Chemical nature
(iv) Pyrethroids
Pyrethroids are synthetic relatives of natural pyrethrin esters obtained from Chrysanthemum flowers
pyrethroids require lower application rates and are generally less toxic to animals
Pyrethroids are highly toxic to beneficial insects and extremely toxic to fish
Examples of pyrethroids are allethrin and dimethrin.
Pesticides Use
Public Health:
Animals can act as a carrier for infectious diseases, making it easier to attack the animal instead of the disease itself.
Mosquitoes are an example of a vector that can transmit diseases
DDT is a pesticide used to control mosquitoes that carry malaria
Pesticides use
2. Agriculture
The Green Revolution increased agricultural production worldwide, especially in developing countries..
High-yielding varieties (HYV) have a larger proportion of their structure usable for food, increasing the harvest index.
HYVs require large amounts of fertilizer, water, and pesticides to perform well.
Pesticides use
3) Forestry
Damage to forests from pests is difficult to estimate, but losses include:
* Reduced growth rates
* Loss of reproductive ability
* Direct mortality of trees
* Loss of recreational value
Pesticide Effects on Aquatic Communities
They impact fish species (non-target organisms)
They contaminate groundwater (due to their persistence)
They bioaccumulate and biomagnify (food chain magnification)
Pesticide Effects Non-Target Species
Pesticides can cause death in aquatic ecosystem when they runoff
DDT was sprayed in large amounts in New Brunswick forest in 1952
Low levels of chronic exposure to pesticides can lead to health risks such as cancer
Frogs are especially susceptible to pesticides due to their thin skins
Human are a non-target species for pesticide use
Pesticide Persistence in the Biosphere
The persistence of a pesticide depends on the environment
Pesticide persistence can contaminate groundwater
Pesticide Food Chain Magnification
Persistence of pesticides is related to food chain magnification.
The study found higher DDT residues at higher trophic levels.
It is unclear whether the higher concentration is from the water or from consuming food rich in DDT.
Pest Resistance
certain pesticides become virtually worthless for controlling pests,
a large amount of money must be spent to achieve a satisfactory level of pest control
Alternatives to Synthetic Pesticide Use Biological control
Ladybugs reduced the pest population,
is the introduction of natural pest predators, competitors or pathogens to a cropland
Genetic control
is the use of natural hormones to alter the growth or development of a pest
Chemical control
Using hormones or natural biochemicals to alter pets growth or development and make them unable to grow, feed or reproduce
Two classes chemical methods to control pets
Using pheromones to attract or confuse insects, e.g., to trap or prevent mating.
Metals pollution
Metals are toxic to aquatic organisms and humans at high exposure levels
Some metals (such as iron and zinc) are essential micronutrients
Most metals are insoluble in water with a neutral or basic pH
They are rapidly adsorbed to particulate matter or assimilated by living organisms
toxic metal pollutants
Mercury (Hg) Production and Uses
Mercury is found in all terrestrial rocks and soils, but concentrations are low.
Cinnabar is the only ore that contains significant concentrations of mercury.
Global production of mercury has declined due to health concerns.
used as a catalyst in the production of polyvinyl chloride (PVC), the most widely used plastic in the world.
- mercury was used in the chlor-alkali industry, dry cell batteries, antifouling paints, electrical apparatuses, thermometers, dental fillings, mercury-based fungicides, and pharmaceutical products.
Fluxes to the Environment
Inputs to the atmosphere
anthropogenic source for
Mercury= coal
Cadmium= smelters/coal
lead= smelters
Sources of Hg to the atmosphere include:
Mercury = Volcanoes
Cadmium= River runoff /Atmospheric deposition
Mercury ( Hg) Inputs to Aquatic Systems
Rain washes Hg from the atmosphere
Direct discharge of industrial wastewaters is another significant source of Hg to aquatic systems
Speciation of Mercury
The toxicity of mercury depends on the chemical form it is in
Mercury can be classified as organic or inorganic
Inorganic Unreactive and generally not dangerous
Organic Reactive and dangerous
What makes MeHg+ so dangerous?
because it is easily absorbed by the body and can travel freely throughout the body, including across the placenta and blood-brain barrier, as well as through breastmilk
MeHg+ is more lipophilic and reactive, and its concentration increases as it moves up the food chain from producers to humans
Mercury (Hg): Impacts to Aquatic Organisms
Aquatic organisms are sensitive to MeHg+ just like humans
These organisms spend their whole lives in water, making them more vulnerable to mercury contamination
2) Cadmium (Cd): Production and Uses
Cadmium occurs in low concentrations in rocks and soils
It is mainly obtained as by-product of mining other metals
Cd used in Ni-Cd batteries, pigments, plastic stabilizers
Cadmium (Cd) :Toxicity
Cadmium is not essential for human health
Only one species of Cd, Cd2+, is toxic
Once ingested, Cd is distributed throughout the body via the bloodstream
The highest concentrations of Cd are found in the liver and kidneys, causing damage or failure
Cd cannot penetrate the placenta or blood-brain barriers.
3) Lead (Pb): Production and Uses
Lead (Pb) is found in rocks and soils and is easily separated by heating.
It has been used historically by the Romans to line aqueducts, by the Greeks and Romans to line cooking vessels, and by Europeans to sweeten wine.
Today, Pb uses are mainly industrial, including batteries, ammunition, paints, pigments, and glass and ceramic products.
Lead (Pb): Production and Uses
Batteries Paints , pigments , Ammunition
Lead (Pb): Environmental Impacts
Analyses of marine sediments suggest significant historical lead contamination
Seawater analyses show that surface waters (0-500m) are enriched with Pb compared to deep waters.
Human Health
Exposure through food
Humans are mainly exposed to Pb through food.
Atmospheric deposition due to smelting and coal combustion is a significant cause of contamination.
Pb has an atmospheric lifetime of a few days to a month, so emissions can easily reach farmlands.
Another source of contamination is lead-soldered cans
Canned foods make up 10-15% of American diets, and FDA estimates that 20% of Pb in an average daily diet is from canned food
Exposure through drinking water
Pb found in drinking water from raw water supply and corrosion of plumbing materials
Corrosion of plumbing materials is more common
Tap water often has higher Pb concentration than water entering distribution systems.
Pb lead to a variety of health impacts
Anemia , Damage to the central nervous system , Kidney damage, Effects on children and reproduction
Case Study: Grassy Narrows, ON
- The Dryden Chemical Company discharged mercury into the Wabigoon-English River System, leading to contamination.
- Mercury poisoning occurred among the Grassy Narrows and Whitedog First Nations populations.
- Mercury poisoning is expected to continue due to leaking mercury wells.
Case Study: Itai-Itai Disease
Two physicians reported a mysterious disease in the Jintsu River basin of Japan in 1955.
Symptoms included severe pain, kidney lesions, and loss of calcium from the bones.
- The cause of the disease is linked to the Mitsui Mining Company’s discharge of wastewater into the Jintsu River that contained high levels of cadmium and zinc, as well as nutritional deficiency.
Flint Water Crisis
Flint River not properly treated and contaminated by untreated materials
City switched to cheaper water from Flint River , which was not treated adequately
Neglect of proper maintenance and treatment led to high levels of lead and TTHM, causing health issues and fatalities
Groundwater
water that occurs in permeable saturated strata of rock, sand or gravel called aquifers”
Groundwater Pollution
two main types of aquifers:
Unconfined aquifers are filled with water that freely flows to the surface
Confined aquifers are filled with water that is held in place by impermeable layers of rock or clay
Overdrafting Groundwater
Aquifer recharge occurs when precipitation exceeds evapotranspiration.
Groundwater Pollution = Natural Process
Some pollution incidents can occur naturally, such as the leaching of certain ions from deposits of uranium.
Examples of natural pollutants include chloride, sulfate, fluoride, iron, and arsenic ions
Groundwater pollution human activities
Groundwater pollution is mainly caused by human activities.
The activities that contribute to groundwater pollution include waste disposal accidents, agricultural activities, mining, highway deicing, acid rain, saltwater intrusion, overdrafting, improper well construction, and maintenance
Septic Tanks
- Bacterial and nutrient pollution from septic tank leakage
- Contamination of groundwater and surface water
- Damage to aquatic ecosystems.
Saltwater Contamination
Contamination of fresh groundwater can occur by several mechanisms
Overdrafting of freshwater aquifers can cause saltwater intrusion from the saline groundwater below
Highway deicing can lead to groundwater contamination when deicing salts percolate into underground aquifers
Groundwater Pollution: Fracking
- Migration of methane and other gasses into groundwater
- Disposal of wastewater containing chemicals used in fracking into groundwater
- Leaking of brine and other toxic substances into groundwater.
Groundwater Pollution: Sewage
Leaks in sewer lines due to: age, disruption by tree roots, seismic activity, poor construction
Leakage from inadequately sealed sewage lagoons
Improper land disposal of treated wastewater * The principal components of sewage that are a threat to groundwater are: nitrates, heavy metals and pathogens
Groundwater Pollution: Mining
Coal deposits containing iron pyrites can create sulfuric acid, which contaminates groundwater.
Drainage water and wastewater from metal mines can contain heavy metals that pollute groundwater.
Groundwater Pollution: Leaking Underground Storage Tanks
Underground storage tanks have been used to store gasoline and other petroleum products underground
were previously made of bare steel and therefore these tanks have begun to leak
Gasoline, diesel, kerosene and oil have contaminated aquifers
Groundwater Pollution: Illegal Disposal
The costs of proper disposal of hazardous waste are increasing, leading to more illegal dumping incidents.
ABM Disposal was convicted for dumping dangerous pharmaceutical wastes into a groundwater
Illegal dumping today is complex and hard to locate.
Groundwater Pollution: Magnitude of the Problem
EPA study indicates 0.5-1% of US aquifers contaminated
Contamination affects areas reliant on groundwater
39 public wells in San Gabriel Valley & 19 rural CA wells closed due to contamination
Case Study: Bhopal’s Second Disaster
Gas leak caused many death and injuries
Samples revealed general contamination of the area
VOCs were present in groundwater above WHO guidelines limits
Case Study: Coal’s Poisonous Legacy
Burning coal produces hazardous chemicals that have polluted groundwater.
The USA conducted a study in 2018 which showed that 91% of coal plants had dangerously high levels of toxins.
Specifically, 52% had excessive amounts of arsenic and 60% had too much lithium in the groundwater.
Two of the most contaminated sites:
In Texas, levels of cadmium and lithium in groundwater have been found to be over 100 times the safe level near a family ranch near a power plant. 2. In North Carolina, cobalt levels in groundwater near a power plant were found to be over 500 times the safe level. 8 other pollutants were also present at unsafe levels. 3. The two sites are highly contaminated with dangerous pollutants, posing a threat to public health.
