Enviro Final Flashcards
How can we e exposed to VOCs?
Ingestion
Inhalation
Dermal Absorption
What are the main systems affected by VOCs?
Hematologic, Nervous, Immune
Benzene toxicity can cause what pathology?
Leukemia due to bone marrow suppression
What is the component of teflon?
Polytetrafluorethelyne (PTFE)
What water soluble substance prevents access to lower respiratory tracts?
formaldehyde
The VOC is 25x more reactive that Benzene and is a commonly used “huffing” agent
Toluene
This VOC is used in dry cleaning clothes
Tetrachloroethylene (PERC)
What VOC is the precursor to medication and found in oral anesthetic agents like Carma and Chloraseptic?
Phenol
What is the most common VOC that is potentially hazardous to people working in histology labs>
Xylene
What is the source the new car smell
Vinyl Chloride and PVC
What is the main ingredient in mothballs?
Napthalene
What is the major component of tar from charred grilled foods?
Benzo-a-pyrene
What does PAH stand for?
Polyvinyl aromatic hydrocarbon
What is the most concerning pathology from Asbestos?
Mesothelioma
Which #s are the safest plastics?
2 and #4
What is used in plasticizers and are concerning due to leeching abilities?
Phthalates
What is the substance in packaging and metal can coating?
Bisphenol A (BPA)
What is the species of black mold?
Staphbotrys chartarum
What is the major sever health effect of vinyl chloride exposure from off-gasing/ leeching?
Hepatic Angiosarcoma
What are the 6 components of smog?
Ground level ozone Particulate matter CO NO sulfur dioxide lead
What is a xenobiotic?
Any substance that is foreign to the body
What are the 3 routes of toxin excretion?
Urine
Bile
Breath
What are 3 route of toxin absorption?
Ingestion
Inhalation
Dermally
What is the predominant CYP in the liver?
3A4
How does fasting affect biotransformation? Is fasting a good idea for biotransformation?
fasting is not a good idea because it requires energy that has to be spared in the fasting state at the expense of gluconeogenesis
What are MRLs?
limits set by the EPA to determine how much pesticide is in our food
Which heavy metal is common in organic form in shellfish and is the reason you should test someone with a weak immune system?
Arsenic
What are the 2 pollutants that form ground-level ozone?
NO and VOCs
What is the primary cause of acid rain?
SO2 and NO
What is the immune response associated with eosinophilic responses and atopy?
Th2
What are the 2 metal exposures that can lead to inability to kill candida?
Mercury and Lead
What is the main health effect of CO poisoning?
tissue necrosis and cell death
What particulate matter size is most concerning because of the ability to penetrate tissue from the blood?
0.1 microns
What form of mercury bioaccumulate in fish and is most concerning for humans?
methylmercury
What type of pesticide is DDT?
Organochlorine
Methylglobinemia is a result of exposure to what?
Nitrate fertilizers
Bioaccumulation definition:
accrual of toxic chemicals in tissue or a particular organism/ food chain
Who is the first female MD in the USA?
Elizabeth Blackwell
Sick building syndrome vs Building-related illness?
SBS: symptoms of illness when in a building but without specific known cause
BRI: illness from a building with an identifiable cause
What is the main chemical in Brazilian blow-outs?
Formaldehyde
What maternal occupation is at increase risk for cleft palate in their children?
preschool teachers
What are the components of natural gas?
fossil fuels, hydrocarbons
What are the health effects of natural gas?
hematologic changes with exposure to hydrogen sulfate High RBC, High HCT, HGB, PLT, LOW WBCs)
What exposure risk is there for a broken fluorescent bulb?
mercury
What is the common chemical in fabric softeners?
Phthalates
What is the agent added to vaccines to promote immune response?
Aluminum
What does OSHA stand for?
occupation safety and health administration
What is MSDS?
Material Safety Data Sheet
What is the 4th review?
study reporting the human exposure to environmental chemicals, updated regularly
Chemical found in forest fires, volcanoes, crude oil, exhaust and cigarettes?
Benzene
Chemical founding paint thinners, added to gasoline and adhesives?
Toluene
Chemical used in histology labs, found in coal, petroleum and wood tar
Xylene
Main effect of Xylene?
CNS depression
While volatile crystalline solid that is produced from petroleum?
Phenol
Used in plywood construction, automotive, appliance parts, a plastics precursor:
Phenol
Used adhesive glues, dyes, pressed wood, carpets, particle board:
Formaldehyde
What are health effects of Formaldehyde?
UPPER respiratory tract and mucus membranes symptoms
What is Acroosteolysis and what can cause it?
dissolution of terminal phalanges and SI joints0 caused by PVCs and vinyl chloride
From combustion of carbon-based fuels and contains multiple benzene rings:
PAH
What are the 2 forms of PAH?
Low molecular weight (eg. Naphthalene)
High molecular weight( eg Benzo-A-pyrene)
From charred grilled foods and tar:
PAH, specifically Benzo-A-Pyrene (HMW)
What is the most carcinogenic component of tobacco smoke?
PAH, specifically Benzo-A-pyrene (HMW)
What is the first carcinogen to be discovered?
Benzo-A-pyrene
What is the metabolite found in 2nd and 3rd hand smoke?
Continine
This is found in electrical, heat, sound, brakes, clutch and tiles:
Asbestos
What are semi-safe plastic #s?
1 and 5
Is polyvinyl chloride plastic safe?
Nope, made from #3 plastics
Are IV tubing and bags safe?
Nope, made from #3 plastics (PVC)
What are the health risks of PVC?
Increased CVD and Nervous diseases
What are plasticizers?
Phthalates that leech easily
What the health effects of phthalates?
endocrine disruption
What are the acute exposure sxs of polystyrene?
mucus membrane and respiratory irritaiton
What are the chronic exposure sxs of polystyrene?
N/V, fatigue, cognitive loss, neural toxicity, renal and hepatic pathologies. can affect iron absorption
What are BPAs and where are they used?
Bisphenol’s found in food packaging, metal can coatings
What are side-effects of BPAs?
Endocrine disruption, xenoestrogens
What is the AQI?
Air Quality Index: developed by the EPA to indicate pollutant air quality
Whats the safe size of particular matter and why?
PM10 microns or greater, because it cannot get deposited in the lungs
What is the main component of haze?
particulate matter (PM 2.5)
What are the 2 classes of Acetylcholinesterase?
Organophosphates
Carbamates
What type of Acetylcholinesterase was used as a nerve gas in WWII?
Organophosphate s- banned in 1970s
How do fertilizers affect our health?
Contains nitrates that alter iron in hemoglobin from ferrous state to ferris state. This then forms methemoglobin which cannot carry oxygen
What is LD50?
Median lethal dose that will cause 50% death of a test group. The lower the LD50, the higher the toxicity
What are some common mechanisms to heavy metal toxicity?
enzyme inhibnition, disruption of membranes and transport, disruption of mitochondria, decreased neuronal function binding of sulfa groups causing protein misfolding....
Where is lead commonly found?
dust, soil, paint
Who is at greatest risk of lead poisoning?
children, pregnant women
Where is lead most commonly found in the environment?
pre 1978 homes
What jobs have high lead exposures?
smelting, mining, auto repair, plumbing, military
What hobbies have high lead exposure?
painting, stained glass, pottery, shooting
What products still contain lead today?
computers, ceramics, pewter, jewelry, auto batteries
What are S/Sxs of lead toxicity?
usu asx, decreased learning, low IQ, impaired speech, impaired hearing, body pains, fatigue, HA, tremor, weight loss, constipation, paralysis, seizures, lead lined gums
What is the best test for lead toxicity?
blood
What are acceptable BLLs for adults and children?
Adults: <20mcg/ dL
Children: <5 mcg/dL
What is seen on imaging to reveal lead toxicity?
abdomen shows lead based items swallowed. Long bones show lead lines
What are 3 types of mercury?
elemental, organic, inorganic
What are 2 types of organic mercury?
methylmercury
ethylmercury
Where is methyl mercury found?
fish (bioaccumulates)
Where is ethyl mercury found?
preservatives, vaccines
Where is elemental mercury found?
thermometers, barometers, dental amalgams, released from smelting, fossil fuels, mining
What are health risks of mercury exposure?
neurotoxicity, teratogenic
Bioaccumulation vs biomagnification
Bioaccumulation: substance builds up in one species
Biomagnification: eating animal that has accumulated substance
Where is cadmium found?
Battery manufacturing, pigmentation, coatings, plastic stabilizers, MOSTLY FROM CIG INHALATION
Where does cadmium accumulate?
Liver and Kidneys
What are health effects of cadmium?
Iron deficiency, kidney damage, lung cancer
Why is chelation of cadmium concerning?
it will need to be excreted through the kidneys, possibly doing further damage
Where is arsenic found?
medicine, cosmetics, paint, pigments, wood preservatives
What is the best test for acute heavy metal exposure?
blood
Why is hair testing not good?
can have falsely high level because hair heavy metals won’t reabsorb into body and hair is exposed to dyes, shampoos, etc.
hair testing is good for methyl mercury only
What is depuration?
process of free body of impurities
What is detoxification?
process of making toxic substances more water soluble
What is nasal fatigue?
ability to stay in an area that originally irritates the nares but , after time, the smell is no longer detected
What are major storage sites in the body?
adipose tissue, bones, liver, kidney
What are routes of excretion of chemicals?
urine, bile, exhalation
what are the problems with the research surrounding xenoextrogens?
Mostly done on animals, and half-lives will differ in humans
What patient population is best for stool testing?
children
What are the best chelators for mercury?
DMPS
(DMSA is best for lead, then mercury)
(EDTA is mostly used for lead, although it does have greater affinity for mercury)
What administration method is best for chelation?
IV
Why avoid seafood 7 days before challenge testing?
to prevent falsely elevated arsenic or mercury
What is the best method for acetylcholinesterase testing?
whole blood and plasma
What is the theory behind hydrotherapy for treatment of heavy metals?
increased bile dumping?
Why is low temperature sauna beneficial for detoxification?
increases lipolysis and can increase excreting of heavy metals stored in adipose tissue
What supplements increase glutathione production?
(glutathione is not well absorbed orally)
NAC 1500-1800 mg/day
L-cystein
What are the most supportive supplements for heavy metal exposure (and dosages!)
C: 6-12 g/day (ROS scavenger)
Fiber (helps bind bile)
Selenium 2 mcg/day (increases metal excretion and phase 2 detox)
Zinc: 30mg BID-TID (give copper too) (mercury depletes zinc)
What are the diagnostic criteria for MCS?
- Sxs reproducible with repeated chemical exposures
- condition has persisted for significant time
- low levels of exposure results in manifestations of syndrome (i.e. increased sensitivity)
- Sxs improve when the triggering chemicals are removed
- responses often occur to multiple chemically unrelated substances
- Sxs involve multiple organ systems
This chemical can penetrate most clothing
Xylene
What is found in pipes, insulation, siding and shower curtains?
PVC, Vinyl Chloride
What is HCA?
Heterocyclic amines (from grilling foods) (from HMW benzo-a-pyrene)
What are some prevention strategies to protect against PAHs?
stop smoking, limit grilled meats
increase brassicas
increase antioxidants
marinade in acids
what plastic # is transvaginal mesh and diapers?
5
What are the minor sources of air pollution?
nail salons, dry cleaners, auto and body shops
What are CFCs and what are their common use?
Chlorofluorocarbons and found in refrigerants, solvents and foam blowing agents
What soil pesticide was removed due to its biomagnification effects?
organochlorines (DDT)
How does mercury get through the BB?
its not fat soluble, transported by ending to sulfhydryl groups on cysteines
What is NAC use controversial in detox?
cysteine increase means more can get through the BB because methymercury binds to it to pass through the BBB
lead poisoning results on CBC:
microcytic hypochromic anemia with basophilic stippling
Reference range for whole blood mercury:
<5ug/L
What has increased absorption when there is iron deficiency?
Cadmium
How does cadmium contribute to osteomalacia/osteoporosis?
increased urinary excretion of calcium and phosphorous and decreased hydroxylation of Vit D metabolites
Where is arsenic absorbed in the body?
GI tract (small intestine)
What is biotransformation?
conversion of lipid soluble xenoestrogen into water soluble substance for excretion
What are some inhibitors?
heavy metals, trauma, obesity
circadian clock of glutathione production?
6pm GSH cycles between oxidation and cycled back to glutathione by glutathione reductase. If a heavy metal is present, then replenishment cannot occur, leading to GSH deficiency
Th1 vs Th2 cytokines:
Th1: IL-2, IFNg, M0 activity
Th2: IL-4, IL-5, IL-10
DS, Dioxin, DDT can cause atrophy of what glandular cells?
thymus
PCB exposure may make people prone to what?
increased allergic response
PAH exposure has decreased activity in what organs?
spleen and thymus
lead and mercury decrease ability to kill….
candida
What supplementation can be protective of immune function with cadmium exposure?
selenium
What is the main toxin causing concerns with reproductive problems in offspring?
DES
Half-life of genistein and daidzein (soy)
5-6 hours
what toxin affects the thyroid?
PCBs- bind thyroxine
What tests must you do before doing any specialty testing?
CBC, CMP, Lipids, complete UA, HCG, G6PD, TB
most accurate test for body burden of heavy metals:
none exists
What is DMPS best for, IV or oral and common SEs?
Mercury
IV best, oral is available
SEs: feeling happy, exhausted, N, dizzy, rash
dose: 3-5 mg/Kg body weight
what is DMSA best for? best route and SE?
lead Oral best (20-30mg/kg body weight on empty stomach)
SE: GI dysfxn, rash, DEF of essential elements, mood changes
What is EDTA best for? best route and SE?
lead (even though mercury is high affinity)
IV best (50mg/kg body weight)
SE: hypotension, hypoglycemia, hypocalcemia