Waste management and soilborne diseases Flashcards
What does waste accumulation cause?
Waste accumulation causes water, soil, and air pollution.
What can happen if waste comes into contact with food?
Wastes can accidentally tough and contaminate foods
Waste becomes a breeding ground for?
Pests
Name the laws that the US has made to improve environmental health.
1906 – Food & Drug Act = pure food
* 1947 - Insecticide, Fungicide, and Rodenticide Act = control pesticide wastes
* 1965 - Solid Waste Disposal Act
* 1970 - Clean Air Act
* 1972 - Clean Water Act
* 1982 - Nuclear Waste Policy Act
✓ Requirements for disposal of high- level radioactive wastes
Name the ways in which you can classify waste?
- The state of waste
- Biodegradability
- Toxicology
- Chemistry, biotic, and abiotic composition of the waste.
Describe how to classify waste based on its state.
- Based on state of the waste
a. Solid wastes (e. g. plastics, feces, hooves, horns, & bones from
slaughterhouses)
b. Liquid wastes (e. g. sewages from residents, wastewater from
slaughterhouses, & industries)
c. Gaseous wastes (CO, NO2, SO2, O3, ammonia)
Describe how to classify waste based on its biodegradability.
- Based on biodegradability
a. Biodegradable (paper, organic wastes)
b. Non-biodegradable (glass, metals, etc.)
Describe how to classify waste based on toxicology.
- Based on toxicology
a. Toxic wastes (e. g. chemical & nuclear wastes)
b. Non-toxic wastes (e. g. food leftovers)
Describe how to classify waste based on chemistry, biotic, and abiotic composition of the waste.
- Based on chemistry, biotic & abiotic composition of the waste
a. Biological (infectious) wastes
b. Chemical wastes (metals, pesticides, organic vs. inorganic drugs)
c. Radioactive or nuclear wastes
d. Physical wastes (e. g. glass, nails, food leftovers, feces, bones)
Name the different sources of waste.
- Household
* garbage
* toiles - Agricultural Waste e.g.,
* Animal farms
* animal slaughterhouses - Industrial waste
- Commercial/public centers:
✓ Hospitals,
✓ research centers, laboratories,
✓ schools, colleges, universities,
✓ shops,
✓ offices
✓ Airports
Name the different forms of waste the USA produces each year.
- 292 million tons of municipal solid wastes e. g. papers, food leftovers, plastics, textiles in 2018
- One billion tons of fecal wastes from humans, cattle, pig, & poultry each year
- Million tones of bones, tendons, blood, sewages, etc. at abattoir
- Air pollution with large quantities of dispersed particles (e. g. cement), hydrocarbons, CO, CO2, NO, NO2, SO2, O3, etc., from industries
- Heavy metals are used in industries for manufacturing products, which can
contaminate soil, water, food, plants, fish, animals and humans.
How much fecal waste is produced in the USA annually?
How is this calculated?
As per EPA, about 1x109 tons of fecal material produced in U.S. each year
1. - Human (0.01%)
2. - Poultry
3. - Cattle
4. - Swine
Formula to calculate total
fecal kg produced/day/animal
= 0.01 x animal body weight
(kg) to the power of 0.83
Describe waste products produced by abattoirs.
After we slaughter, a lot of waste left behind.
See lower left
Name the Wastewater sources at different stages of processes in slaughterhouses
What water source is vital for washing carcasses?
Clean POTABLE water availability is critical for washing carcasses and the entire building.
✓ In the absence of water everything in the
building is horribly dirty
What is the fate of wastes from abattoir, industries, human & animal feces, farms, & municipal sewages?
The fate of wastes from abattoir, industries, human & animal feces, farms, & municipal sewages sometimes ends in polluting air, soil & water.
Abattoirs generate millions of gallons of wastewater after washing that often pollute the streams and rivers of lower-income, rural communities. This waste pollutes rivers and water bodies –> fish killed.
Location of slaughterhouses in U.S. that discharge more than 250,000 gallons of wastewater per day directly into U.S.
✓ rivers,
✓ streams and
✓ other waterways
- Sometime the waste disposal act (1965) & clean water act 1972 are not respected.
- The abattoirs committed Frequent Permit Violations in chemical contaminants in
the discharges e. g. total maximum daily load of chlorine.
Describe the effect of natural disasters on water sources.
What types of health hazards are present in wastes?
Source/origin of the hazards
1. GIT of humans & animals
2. Lung of humans & animals
3. Skin of humans & animals
4. Industries
Discharges and gaseous wastes from industries have what effect on our environment?
Discharges & gaseous wastes from industries can have chemical and biological hazards e. g. anthrax spores
Describe how hazardous gases & particles from industries may pollute air, water, & soil.
- ozone (O3)
- carbon monoxide (CO)
- sulfur dioxides (SO2)
- nitrogen dioxides (NO2)
- lead
- atmospheric particulate matter e. g. cement
- Aerosolized spore of pathogens e. g. anthrax
& fungi in tanneries
Rain & winds make pollutant in air to drop on people, soil, & water bodies.
Discharges from industries may contain chemicals that pollute water, soil & air such as?
- Antimicrobials
- Heavy metal
- Pesticides
- radiological hazards
- Detergents
Gaseous wastes from respiratory system of humans & animals may contain?
biological hazards
Name the waste gases from humans?
CO2
Name the waste gases from animals?
CO2, Methane, Ammonia
Human & animal fecal waste contain 100s of pathogens that contaminate water, food, & soil
There are Spore forming: Anthrax, bacillus, clostridium, bacteria 2 genera, virus = no, fungi = almost all, protozoa = almost all
and non-spore forming.
Waste from what parts of the body can contaminate water, food, & air with pathogens? How does this happen?
gut, skin, & respiratory tract
If there is no control on waste disposal, pathogens
Pathogens from digestive tract contaminate water and food. They are also contagious, foodborne, and waterborne.
Pathogens in the feces & wastes spread to humans through 7 Fs fecal-oral transmission pathways. Name these pathways.
Pathogens in feces are recycled between the GIT & the environment through the fecal-oral route if not controlled
Contaminated air with viral, bacterial, & fungal pathogens
can be recycled between air & respiratory tract
How are fecal-oral transmission pathways controlled?
How is waste treatment controlled via thermal waste treatment methods?
Thermal waste treatment methods
1. Burning (incineration)
2. Boiling
3. Autoclave
4. UV treatment
5. Microwave use
How is waste treatment controlled via chemical waste treatment methods?
Chemical waste treatment methods
1. Oxidation by treating with radicals e. g.
hydroxyl radical .OH, ozone, chlorine)
2. Hydrolysis using sulfuric acids followed by
neutralization by alkaline (NaOH or Ca(OH)2)
3. Detergent and disinfectants
How is waste treatment controlled by physical waste treatment methods?
Physical waste treatment methods
1. Screening (separating by size)
2. Drying (dehydration)
3. Evaporation
4. Sedimentation
5. Membrane Filtration
How is waste treatment controlled by biological waste treatment methods?
Biological waste treatment methods
1. Composting/decomposing
2. Anaerobic decomposition
3. Aerobic decomposition
4. Enzyme treatment
How is sludge treated before it is disposed?
- The commonly used 7 sludge treatment methods include thickening, digestion, dehydration, drying,
incineration, solidification and comprehensive utilization. - Among them, sludge thickening, digestion and dehydration are the main treatment methods widely used at
present. - The most common sludge digestion options include anaerobic digestion, aerobic digestion, and composting.
After treating the sludges, how is waste treated?
What is soil made up of?
Soil is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life
What function does soil serve?
Soil provides readily available nutrients to plants and animals by converting dead organic matter into various nutrient forms
A gram of soil contains how many microorganisms?
A gram of soil can contain 10 billions of organisms, belonging to 1,000 species, mostly microbial and largely still unexplored.
What is the mean prokaryotic density of soil?
Soil has a mean prokaryotic density of roughly 108 organisms per gram, whereas the ocean has no more than 107 prokaryotic
organisms per milliliter (gram) of seawater
Does soil harbor pathogens? If so, what types?
Soil also harbors pathogenic microorganisms, spores, fungi, protozoa, parasites, and arthropods.
➢ Pathogens from digestive tract of animal kingdom also pass to the ecosystem to join soil
What chemical hazards contaminate soil?
A. Chemical hazards from farms, industries
1. organic chemicals – pesticides,
fertilizers, herbicides
2. Inorganic chemicals - heavy metals,
acids, alkaline
What biological hazards contaminate soil?
B. Biological hazards from municipal, farm
animal waste, & abattoirs
1. Spore-forming microbes
2. Non-spore forming microbes
Where are soil-borne pathogens commonly found?
- Soil-borne pathogens are commonly found in diverse
locations, including:
✓ soil,
✓ sewage,
✓ marine sediments, e. g. Botulism
✓ animal and plant products,
✓ intestinal tract and
✓ in wounds of man & animals
How are soil-borne pathogens classified?
Name the spore-forming soil-borne microbes and the diseases they cause.
Spore forming microbes -
Bacillus,
Clostridium, Fungi, & protozoa spp.
1. Bacillus anthracis – anthrax (edema & hemorrhage)
2. Bacillus cereus – foodborne gastroenteritis
3. Clostridium tetani – tetanus (rigid paralysis)
4. Clostridium botulinum – botulism (flaccid paralysis)
5. Clostridium perfringens – foodborne gastroenteritis & gas gangrene of deep wound
6. Clostridium difficile – causes pseudomembranous colitis
Name the non-spore-forming soil-borne microbes and the diseases they cause.
- Non-spore forming pathogens –
Enterobacteriaceae, cestodes, nematodes
*
Enterobacteriaceae – oro-fecal route transmission & cause gastroenteritis.
*
Burkholderia pseudomallei – pneumonia, septicemia, shock & death
*
Listeria – oral transmission and causes gastroenteritis, abortion
*
Ligionella – launched from soil/water for airborne transmission (causes pneumonia)
Soil bacteria may cause what types of diseases?
gastrointestinal, wound, skin, and respiratory tract diseases.
- Bacillus and Clostridium are _________, Gram-________ bacteria.
- ______ are some of the most studied spore-producing organisms in the world.
- Intestinal spore-forming protozoa are transmitted either by ______ from person to person or through contaminated water or food by an infectious particle called a ?
anaerobic, positive, Fungi, stool, spore or oocyst.
Spore-forming bacteria attack their host using?
exotoxins
Which spore-forming bacteria produces the most toxic exotoxin? Second most impactful?
- The most dangerous spore-former is
Clostridium botulinum
which produces a potent neurotoxin that can prove fatal. - The most common food poisoning (intoxication) from a
spore-former is caused by
C. perfringens
Name the alternative names used to describe anthrax.
✓ malignant pustules,
✓ malignant edema,
✓ woolsorter diseases,
✓ ragpicker disease
What is anthrax’s disease causing agent?
✓ Spore-forming soil-borne Gram-positive bacteria
✓ Bioterrorism agent
Anthrax can infect which hosts?
✓ major is herbivores;
✓ humans and canines are occasional
Can be domestic or wild?
Anthrax
Depressed black eschar
What is the reservoir/habitat that anthrax occupies?
Infected domestic & wild herbivores contaminate the soil
during shedding the bacterium due to hemorrhage or death
What is Anthrax’s mode of transmission in humans?
- cutaneous by contact with infected tissue of farm animals dying of anthrax or
- contact with contaminated hair, wool, hides
Which population groups are most at risk of contracting anthrax? What is the incubation period?
High risk group: Occupational disease of:
✓ vets,
✓ wool, hide or bone sorters,
✓ wildlife experts,
✓ farmers
* Incubation period: 1-7 days but up to 2 months
How can you control an anthrax outbreak in animals?
- Control in animals:
✓ Vaccinate animals;
✓ do not open dead animals for necropsy rather burn the dead body;
✓ do not sale skin of anthrax exposed animals
How can you control an anthrax outbreak in humans?
Control in humans:
✓ Vaccinate people at higher risk e. g. vets
How can you control an anthrax outbreak in products and the environment?
Control in products and environment:
✓ disinfect hides, wool, bones before you handle;
✓ decontaminate soil or effluents from slaughterhouses, tanneries, rendering factories,
Clostridium botulinum
* Biotorrorism toxin
* botulism (flaccid paralysis) by its type A, B, and E toxins.
* Type E toxin is related to:
➢ seafood, fish, and
➢ meat from marine mammals
What are the three forms of botulism?
Three forms of botulism:
1. foodborne intoxication causing cranial nerve paralysis (classical form)
2. wound botulism, and
3. intestinal botulism (< 1 year infant)
Botulism
Soft and hanging loosely
Weakness/relaxatio
n of eye muscle
(flaccid paralysis)
Classic form of Botox (Type E)
Botox is what form of Botox?
Botox type A
What is the reservoir/habitat that botulism occupies?
Reservoir/Habitat: spores are ubiquitous in
✓ soil worldwide,
✓ marine sediments,
✓ agricultural products, including honey,
✓ intestinal tracts of vertebrates including fish
What is the mode of transmission of Botulism in humans?
Mode of transmission to humans:
✓ eating of poorly or broken canned foods,
✓ consuming uneviscerated fish
Name the population group most at risk of contracting Botulism.
High risk group:
✓ infants,
✓ people with wounds that have contact with soil
What is the incubation period for Botulism?
Incubation period: neurological signs (paralysis) appear in 12 - 36 h
How can you control a Botulism outbreak?
Control:
✓ boil or sterilize the incriminated food then bury;
✓ do not feed honey to infants below 1 year;
✓ treat with polyvalent sera (ABE antitoxin)
Tetanus is caused by what microbial agent?
Clostridium tetani
What are the alternative names used to describe tetanus?
Also called Lockjaw because of rigidity of:
✓ neck,
✓ masseter and
✓ trunk muscles
Tetanus
“Resus sardoncus” (abnormal big smile) due to sustained spasm of facial muscle
Shows opisthotonus = “arching or bridging” of head, neck and spinal column
What is the reservoir/habitat that Tetanus occupies?
✓ Intestine of equines & other animals,
✓ soil
What is the mode of transmission for Tetanus?
deep puncture wounds contaminated with soil, feces
What is Tetanus’ incubation period?
Incubation period: 3-21 days
Which population groups are most at risk for contracting Tetanus?
High risk group: workers in contact with:
✓ soil,
✓ swage, and
✓ animals such as Vets and farmers
How can you control a Tetanus outbreak?
Control:
✓ Massive vaccination of human population with tetanus toxoid.
✓ However, priority should be for workers in contact with soil, swage, and animals such as Vets and farmers.
✓ Once vaccinated, the immunity protects for 10 years
Clostridium perfringens causes?
toxico-infection perfringens food poisoning with gas gangrene
What are the two forms of Clostridium perfringens?
Two forms:
1. foodborne gastroenteritis using its type A & C enterotoxins &
2. gas gangrene of deep wound due to wound contamination by soil or feces
What habitat does clostridium perfringens occupy?
Habitat:
✓ spices,
✓ raw meats,
✓ poultry dishes,
✓ soil (levels up to 104 CFU/g),
✓ water,
✓ sewage and
✓ dust.
✓ Asymptomatic fecal carriage occurs in animals
What is the infection dose of Clostridium perfringens?
Infection dose: > 106 CFU/g
What is the incubation period of clostridium perfringens?
incubation period: 8-22 h.
What are the symptoms of Clostridium perfringens infection?
Severe abdominal pain (cramp) with profuse watery or bloody diarrhea.
How can you control a Clostridium perfringens outbreak?
✓ massive vaccination of food animals;
✓ eliminate soil and dust contamination of food;
✓ cook food well above 75C to kill vegetative cells and inactivate preformed toxins.
Clostridium dificile causes?
Diarrhea and colitis
How is clostridium dificile trasmitted?
It is transmitted by touching feces of
infected person
✓ Thus, washing hand is important
Which population groups are most at risk of contracting clostridium dificile?
It attacks mostly people with:
✓ age above 65 years and
✓ people who are taking antibiotics
Nonspore-forming enteric (fecal) pathogens pollute soil and water; hence, become soil-borne as well as waterborne
Most protozoa
& all fungi are
spore-forming
giardia and other worms living inside intestine, tapeworms, nemaqtodes, cestodes live at one stage of their life int he soil
(relisten)
Nonspore-forming enteric pathogens survive for several weeks
outside of the host in soil (soil-borne) & in water (water-borne)
Viruses = particle in environment so they can survive. They gain more life when enter animal adn humans
bacteria = can survive for several weeks in soil despite being nonspore forming
?
Soil-transmitted helminths is the nickname for? Why is this their nickname?
because egg &
larva stages are a free living in the soil
The most known soil transmitted helminths (worms) are:
- Hookworm,
- Ascaris, and
- whipworm (trichuris)
How are soil-transmitted helminths transmitted?
They are transmitted by eggs present in human feces, which
contaminate the soil in areas where sanitation is poor.
Approximately 1.5 billion people are infected with
soil- transmitted helminths worldwide
Describe how helminths “do not care” for their offspring.
Adult live in our body, send out egg and larvae, up to larvae to survive. In the environment the egg hatches and then they come back to us through either of the 7 F pathways.
An estimated 576-740 million people in the world are infected with
hookworm
Human hookworm was widespread in the ___________ United States until the early 20th century but is now nearly eliminated.
southeastern
An estimated 807-1,221
million people in the world
are infected with
Ascaris
lumbricoides (= “Ascaris”). Ascariasis is now
uncommon in the USA
people without proper bathrooms
An estimated
604-795
million
people in the
world are
infected with
whipworm.
How can you control the transmission of soil-transmitted helminths?
✓ periodical deworming to eliminate infecting worms
✓ improved sanitation (toilet) to reduce soil contamination with infective eggs.
✓ health education to prevent re-infection,
soil born comes from human or animal impacted wastes.
In the wastes, there are multiple hazards that we need to control
