Ch. 17 in F/R text:
- mod 56 Human Disease
- mod 57 Toxicology and chemical risk
- mod 58 Risk Analysis
- 1992 Jack in the box-CA, 700 infected, 3 died
- 2002 ConAgra beef, recalled 19 million pounds of beef
- 2005 California spinach
- 2015 Chipotle restaurant
- 2017 IM Healthy granola
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- Epidemic: rapid increase in disease (think of EPIdermis, the top layer of your skin)
- Pandemic: entire continent or world (e.g. COVID19)
- Plague: bacterium from fleas (modern antibiotics can cure this if given in time)
- Malaria: from the Spanish for "bad air", also why Buenos Aires is such a nice place. Plasmodium in blood, no cure, just cure for symptoms. Once you have it, you have it for life, and it can recur. Vaccine recently developed (!)
- Tuberculosis: airborne bacterium (like in Les Miserables), very contagious, modern threat is from drug resistant TB, esp. in Russia (selling antibiotics for alcohol)
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- First showed up in babies, homosexuals and blood transfusion recipients
- No known cure, but can be managed with drugs, which are expensive, so this is still a threat in Sub Saharan Africa, among other places.
- HIV mutates to avoid the immune system, and folks usually die from opportunistic infections, like pneumonia
- "Prion" protein pathogen, basically a toxic protein that survives cooking, originally found in UK, banned all beef from there for a certain time in 1996.
- Caused by using ground up sick cows as feed for other cows (gross!)
- Influenza = Italian for "under the influence"
- Also where we get the word "quarantine" = 40 days off shore from Venice in boats during the plague
- Both jumped from animals to humans (like Covid-19). If this jump is not human-to-human transmitted, then only a few humans die, if it jumps or mutates, then things get serious.
- H5N1 refers to the histology (H) and nucleotides (N) in the virus, so we can discern it from others
- 18000 deaths in 2009 from swine flu
- Severe Acute Respiratory Syndrome, 2002, 10% fatality rate, air transmission, coronavirus
- All boarders from Asia were kept at HPA for the year due to this breakout in Asia
- Person to person transmission, 8000 infected, 10% fatality rate
- another coronavirus in 2012, ME stands for Middle East, 34% fatality rate (!)
- SARS-CoV-2: Coronavirus, airborne and contact on surfaces (also through food), mutated with "variants" with different internal and spike protein structures.
- Named COVID19 for Corona Virus Disease 2019
- Pfizer vaccine 100% effective for kids 12-15
- Vaccines are either binary or solo (Johnson and Johnson), based on testing not on structure
- Vaccines prep the immune system by mimicking the spike proteins on COVID-19, one reason you have an immune response.
- Deb Birx the COVID coordinator said in 2020 400,000 deaths could have been prevented with masking
- #3 cause of death in 2020-2022 behind CV disease and cancer
- "Long COVID". patients have many long term challenges, some have seen vaccine improves their outcome even after exposure
- Exposure impacts everything in the cardiovascular system and kidneys, as it attacks the lining of blood vessels and the angiotensin pathway that regulates blood pressure
- 2 day latency period (no symptoms, asymptomatic)
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Others:
- Neurotoxins-disrupt the nervous system, e.g. insecticides, lead, mercury
- Carcinogens-cause cancer, e.g. dioxin, PCB, many others
- Mutagens-cause mutations and often cancers, e.g. radon, asbestos, formaldehyde, tobacco
- Teratogens-cause birth defects, e.g. mercury, thalidomide, alcohol
- Allergens-cause allergic reactions, e.g. dust, pollen, animal dander
- Endocrine disruptors-interfere with hormones, e.g. BPA
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- Heavy metals (mercury, lead, arsenic)
- Artificial chemicals (PVC, VC, Alcohol, phthalates)
- Pesticides(atrazine, DDT)
- Asbestos is a natural fiber, used in places that can cause cancer through inhalation in humans (insulation, flooring, etc.)
- Radon occurs naturally, and concentrates in lower dwellings or in the lower lobes of your lungs, potent alpha radiation emitter
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APES withgott 6e.14
BPA-bisphenol-A Water bottles, food, baby bottles, tupperware
Endocrine disruptors: what are they, how do they work?
BPA is an estrogen analog: https://en.wikipedia.org/wiki/Bisphenol_A
Hormone mimicry:
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Possible impacts of hormone disruptors:
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- Physical e.g. UV radiation (DNA damage)
- Chemical e.g. drugs, pesticides, venoms, synthetic and natural
- Biological e.g. infectious diseases (vectors)
- Cultural e.g. smoking, COPD, seat belts, hang gliding, swimming with sharks
Non-infectious diseases: genetics + environmental factors, e.g. cancer, heart disease, obesity
Infectious diseases (ID): ebola, influenza, AIDS, SARS, Covid-19
These spread much faster due to air travel, trains, trucks (see AIDS in Africa, bubonic plague, SARS)
Kinshasa "AIDS highway" https://en.wikipedia.org/wiki/Kinshasa_Highway
Toxicology-chemical hazards
Radon: 226 mass, stays in lower lobes of the lungs, found in basements where Uranium ores are present (Colorado, Alaska)
Asbestos: fibrous non-burning insulating material, mined for ages as an insulator, tabletop, flooring, insulation. Fibers in the air cause asbestosis in the lungs, and various forms of lung cancer (carcinoma)
lead: used in many manufacturing processes, batteries, plumbing/solder, gasoline (yes, gasoline as tetra ethyl lead), causes brain retardation (see romans and lead), replaced in gasoline by MTBE, which causes cancer.
PBDE (polybrominated diphenyl ethers) fire retardants (e.g. TRIS), PBDEs are also hormone disrupters
Risk vs. reward (see malaria and DDT)
VOC in drinking water, also atomizers (like in some classrooms)
Heptachlor in green chop hawaii
EDB in water on Oahu (ant poison)
DDT-foggers in 1960’s….
Toxins
Carcinogens-cause cancer, long term or short term
Mutagens-mutate you or your kids (reproductive DNA)
Teratogens-cause birth defects: fetal alcohol syndrome (huge in Russia), thalidomide
Neurotoxins-mercury and other heavy metals (Minamata Bay), many derived from insecticides
Allergens-airborne or food borne
Pathway inhibitors-endocrine disruptors, BPA, Phthalates (plastics)
Exposure can be acute (short) or chronic (long term)
Bioaccumulation-A single creature
Biomagnification-MANY trophic levels, MANY creatures (see below)
Dose response analysis: determining the dose to have some sort of immediate impact, usually on test animals, but can also be part of a "natural experiment" where something happens to a human or other population, not planned, but well documented.
LD50 and ED50 (not the same)
LD50 is the dose that kills 50% of the population, so LD50 means "lethal dose to 50%"
ED50 is the effective dose (ED) in a test, which can be good or bad: good might be aspirin, but usually it means amount to cause some non-lethal effect, like mice losing their hair.
Threshold dose (non linear)
Pesticide poisoning: Yaqui indians, PCB endocrine disruptors
Synergistic effects-combined impact greater than sum of separate impacts, e.g. Endocrine disruptors
Risk probability: perception vs. reality
Regulation: Innocent until proven guilty vs. precautionary principle
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Laws to know:
TOSCA (Toxic Substances Control Act) 1976 in the US
REACH 2007 in EU (see difference below)
12 POPs: persistent organic pollutants: review for AP exam:
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