midterm Flashcards

Question

what is the function of a pesticide

Answer 1

The function of a pesticide is to kill or harm some form of life

Answer 2

All of the chemical insecticides in use today are neurotoxicants and they act by poisoning the nervous system of target (also non-target) organisms. Classes of Insecticides: Organochlorine Insecticides Organophosphate/Carbamate Insecticides Pyrethroid Insecticides

Answer 3

dichlorodiphenylethanes (e.g. DDT) chlorinated cyclodienes (e.g. Endrin) chlorinated cyclohexanes (e.g. lindane) Chlordecone (e.g. kepone) the organochlorineare chlorinated hydrocarbons

Answer 4

Properties which made them good insecticides: low volatility chemical stability lipid solubility slow rate of biotransformation and degradation These properties also led to their demise because of their persistence in the environment, bioaccumulation, and biomagnification through the food chains.

Answer 5

Chronic exposure with kepone can cause impairment of spermatogenesis and epileptic convulsion, and skin rashes

Answer 6

Patch test develops hyperpigmentation in 15-20% of subjects tested with dienochlor - resembles reaction to Balsam of Peru

Answer 7

periodic sequences of persistent tremoring and/or convulsive seizures suggestive of repetitive discharges in neurons. these tremors, seizures can be initiated by tactile and auditory stimuli, indicating that the sensory nervous system appears to be much more responsive to stimuli. There is a characteristic prolongation of the falling phase of the action potential. The nerve membrane remains in a partially depolarized state and is extremely sensitive to complete depolarization again by very small stimuli.

Answer 8

1) DDT affects the permeability of the nerve cell membrane to K+ ions reducing K+ transport across the membrane. (2) DDT alters the Na+ channels, they open normally but are closed (inactivated) slowly. (3) DDT inhibits neuronal ATPase activity particularly Na/K ATPase and Ca ATPase which play a role in repolarization of the neuron.

Answer 9

These insecticides act in the CNS. (1) Mimic the action of the chemical picrotoxin, a nerve excitant and antagonist of the neurotransmitter GABA found in the CNS. GABA induces the uptake of chloride ions by neurons. The blockage of this uptake results in only partial repolarization of the neuron and a state of uncontrolled excitation.

Answer 10

Very slow rate for DDT due to complex aromatic ring structure and chlorination. Half-life is 335 days in cattle. DDT broken down to DDE both nonenzymatically and by cytochrome P450 reductive dechlorination. All metabolites are highly lipophilic.

Answer 11

Aldrin and Heptachlor are converted by cytochrome P450 oxidation reactions to dieldrin and heptachlor epoxide without a change in lipid solubility or toxicity.

Answer 12

In addition to decontamination and supportive treatment, diazepam or phenobarbital may be administered to control the convulsions

Answer 13

Both organophosphate and carbamate insecticides act by inhibiting the action of acetylcholinesterase (AchEase) at the synapse between two neurons or between a motor neuron and a muscle. AChEase is the enzyme responsible for the breakdown of the neurotransmitter acetylcholine (ACh). Organophosphate compounds are irreversible inhibitors of AChEase while carbamate compounds are reversible inhibitors of AChEase. organophosphates cause damage that is irreversible The reaction between an organophosphate and the active site on AChEase (a serine hydroxyl group) results in the formation of an intermediate that undergoes partial hydroylsis with the loss of the "Z" group, leaving a stable, phosphorylated, permanently inhibited enzyme. Signs and symptoms are prolonged and persistent. Without intervention, the toxicity will persist until sufficient amounts of "new" AChEase are synthesized in 20 to 30 days

Answer 14

Collect serum, urine, & clothing samples Hospitalize for severe symptoms Specific treatment Atropine Pralidoxime (2-PAM)--OPs only Workplace restrictions

Answer 15

Reverses SLUD, DUMBELS syndrome Intravenous dose: -Diagnostic 1 mg adult 0.01 mg/kg pediatric -Therapeutic 1 mg - 4 mg adult 0.05 mg/kg pediatric Repeat every 10-30 minutes

Answer 16

(2Pam) Enzyme aging occurs if not treated Treatment effective within 48 hours 2-PAM reactivates cholinesterase Cholinesterase levels rise

Answer 17

phase 1 and phase 2 One reaction, oxidative desulphuration, results in a significant increase in toxicity. In parathion, methyl parathion and malathion, the presence of the P = S reduces the AChEase inhibiting properties of the compound.

Answer 18

Low systemic toxicity Respiratory sensitization Asthma Skin reactions -Paresthesia -Allergic dermatitis

Answer 19

Examples of use -Structural & agricultural -Pet flea control -Pediculicide Vector control -West Nile virus -Aircraft “disinsection”

Answer 20

Prolong inactivation of nerve membrane sodium channels Pyrethroid structure Type I (non-cyano) Shorter inactivation Type II (alpha-cyano) Longer inactivation Type I pyrethroids affect Na+ channels in nerve membranes (both sensory and motor) and gives long afterpotential similar to DDT. Type II pyrethroids cause persistent depolarization and prolonged repetitive firing of sensory receptors and muscle fibers. Both types also inhibit Ca/Mg ATPase resulting in increased intracellular Ca++ levels and increased neurotransmitter release

Answer 21

Decontamination Vitamin E cream Symptomatic therapy Remove from further exposure if needed

Answer 22

Health effects Case reports of eye, skin irritation Death due to ingestion of large amounts Experimental studies fail to show skin irritation Mechanism of human toxicity unknown Surfactant preservative?

Answer 23

2,4,5-trichlorophenoxyacetic acid (2,4,5-T) Derived from tetrachlorobenzene Dioxin byproducts 2,4-dichlorophenoxyacetic acid (2,4-D) Derived from phenol Dioxin contaminants not present

Answer 24

Acute CNS depression Skin, GI, mucous membrane irritation Renal failure, myopathy Chronic Anemia, hepatic, renal effects Tumor formation(?)

Answer 25

Halogenated hydrocarbons -Methyl bromide -Ethylene dibromide, DBCP Inorganic compounds -Sulfuryl fluoride Pro-fumigants -Metam sodium Metal phosphides -Aluminum, Zinc, Magnesium

Answer 26

High vapor pressure Heavier than air Odorless -Chloropicrin (tear gas) added Toxic mechanism -Tissue methylation

Answer 27

Vesicant -Blistering dermatitis Lower respiratory toxicant -Delayed pulmonary edema Central nervous system depressant -Usual cause of death CNS depression Other CNS depressants Pulmonary edema Hepatic & renal disease Acute severe asthma

Answer 28

Central nervous system -Cognitive, behavioral effects -Polyneuropathy Reproductive system -Teratogen -Genotoxic, mutagenic

Answer 29

-Pulmonary ---Dyspnea, cough, delayed pulmonary edema, fatal hypoxia -Renal CNS ---Weakness, nausea, vomiting, restlessness, muscle twitching, seizures

Answer 30

Hydrolyzes to mixture of irritants health effects -Irritant dermatitis -Reactive airways dysfunction syndrome/asthma

Answer 31

Metal phosphides hydrolyze Aluminum, zinc, magnesium Phosphine Colorless, fish/garlic odor Highly explosive, corrosive Rapidly oxidizes to phosphoric acid

Answer 32

Thiocarbamates -Zineb, maneb, ziram, thiram Pthalimide derivatives -Captan, captafol, Substituted aromatics Chlorothalonil, hexachlorobenzene Inorganic Sulfur

Answer 33

Acute Irritant & allergic dermatitis Chronic Chronic dermatitis Possible carcinogens

Answer 34

Resemble rubber accelerator thiuram Sensitization reported in exposed workers

Answer 35

Fungicide- substituted aromatic Blue-gray pigmentation in antecubital area Positive skin reaction to chlorothalonil Diagnosis: Ashy dermatitis -Disruption of basal membrane of epidermis Melanin deposits in dermis

Answer 36

fungicide Potent skin irritant -Animal experiments equivocal Airway irritant

Answer 37

Botanicals Red squill – effects heart Strychnine – blocks glycine receptors in spinal cord - convulsions Inorganics Phosphorous – GI track Thallium – hair loss, nervous system Zinc phosphide – GI track Anticoagulants Warfarin – inhibits blood clotting Vacor – newer blood clot inhibitors

Answer 38

Specialized area of toxicology that deals specifically with animal, plant, and microbial toxins The science of toxic substances produced by or accumulated in living organisms, their properties and their biological significance for the organisms involved

Answer 39

Any agent capable of producing an adverse response in a biological system

Answer 40

Poisonous Animals Animals whose tissues, either in part or in their entirety, are toxic No mechanism or structure for delivery of their poisons Venomous Animals Animals that are capable of producing a poison in highly developed glands Toxin can be delivered during a biting or stinging act

Answer 41

Proteins Amines Lipids Steroids Free amino acids Histamine Phospholipases Etc.

Answer 42

Venom must be “taken apart” to look at components Quality of venom may be destroyed Interplay between various components may be lost

Answer 43

Determined by: Composition Molecular size Amount or concentration gradient Solubility Degree of ionization Rate of blood flow to exposed tissue Site of exposure (or route of exposure!) Is venom injected?

Answer 44

Injection (possible IV injection!) Active transport Facilitated diffusion Pinocytosis

Answer 45

Tissue destruction Receptor-mediated toxicity -Receptors have highly variable degrees of sensitivity -Complex venoms may affect many receptor types (or even sub-types)

Answer 46

Protein binding Variations in pH Membrane permeability Rate of blood flow to a particular site Etc.

Answer 47

Insects, crustaceans, arachnids (scorpions, spiders), and myriapods (centipedes) that are characterized by a chitinous exoskeleton and a segmented body to which jointed appendages are articulated in pairs More than one million species All are not significantly venomous Most don’t have fangs or stingers long or strong enough to penetrate human skin

Answer 48

Signs and symptoms of scorpion envenomation Localized pain Swelling Mild paresthesia Tachycardia and hypertension Rare systemic reactions including fever and muscle fasciculations in adults Systemic reactions in children more common; lead to motor weakness and respiratory paralysis Symptoms often resolve in 12-36 hours

Answer 49

Latrodectus (Widow spiders) Found worldwide in temperate and tropical climates Only female has fangs large enough to penetrate human skin Venom affects neurotransmitter release

Answer 50

latrotoxins Major latrotoxin is a presynaptic toxin which depolarizes neurons by increasing [Ca2+]i Stimulates exocytosis of neurotransmitter at nerve terminals

Answer 51

Clinical symptoms include numbing pain in affected extremity Pain, cramping, and rigidity in large muscle masses Local skin reactions rare Muscle fasciculations Rarely fatal

Answer 52

Initial sting Burning sensation at bite site Swelling and redness in mild bites Serious bite cases exhibit hemorrhage, blistering, pustule formation, necrosis Systemic effects may include fever, nausea, hematuria Rarely fatal

Answer 53

type of arachnida Saliva is toxic Microbacterial organisms transmitted by ticks Rocky Mountain spotted fever, typhus, tick-borne encephalitis, Lyme disease

Answer 54

Caused by bacterium Borrelia burgdorferi The action of Borrelia toxin is to prevent, through its action as a proteolytic enzyme, the release of the neurotransmitter acetylcholine Bite symptoms include fever, headache, fatigue, and a characteristic circular skin rash at bite site If left untreated, infection can spread to joints, lymph nodes, the heart, and the nervous system If caught early, antibiotic therapy is often successful

Answer 55

Centipedes Found worldwide First pair of legs are modified poison jaws Venom contains proteinases, esterases, histamine, etc. Venom causes redness and swelling Necrosis rare

Answer 56

lepidoptera Most possess urticating hairs (setae) which are attached to unicellular poison glands at the base of each hair In most cases, itching and redness subside shortly

Answer 57

Formicidae (Ants) Solenopsis (Fire ants) are clinically important Native to S. America and Southern US Venom contains formic acid, and alkaloids Stings give rise to intense burning, swelling, pustule formation, and necrosis Severe envenomations may result in respiratory difficulties and rarely death

Answer 58

Apidae (Bees) Venom contains phopholipase A, histamine, etc.

Answer 59

insecta Heteroptera (True bugs) Six legs, most have wings Venom has protease function (digestive enzymes) Some bugs have no mechanism to deliver their venom and are therefore poisonous! Envenomation usually very mild

Answer 60

amphibians they are classified and dendrobates and phyllobates

Answer 61

Batrachotoxin Arguably the most toxic naturally produced poison Steroidal alkaloid with high specificity for certain nerve structures in the peripheral nervous system Sodium channel blocker -Locks the channel in the open position Results in constant stimulation and release of acetylcholine -Muscles contract and are unable to relax Death may result from respiratory paralysis

Answer 62

Gila monster Venom contains phospholipases as well as proteolytic and hyaluronidase activities (increases tissue permeability) Venom drawn up via capillary action along grooves in the teeth

Answer 63

Crotalid venoms: Rich in proteolytic activity and thrombin-like enzymes Vipirid venoms: Moderate-rich in proteolytic activity and thrombin-like enzymes Elapid venoms: Little or no proteolytic activity (although phospholipases may be strongly represented), few thrombin-like enzymes, neurotoxic activity! Venoms may cause death in as little as 5-10 minutes

Answer 64

Crotalid and viper envenomation -Hypotension/shock from decrease in circulating blood volume secondary to capillary permeability -Elapid envenomation Respiratory arrest from neurotoxic activity

Answer 65

Contain neutralizing antibodies -Monovalent or polyvalent Antibodies bind to venom components rendering them ineffective

Answer 66

All venoms have the capability of inducing anaphylaxis Anaphylaxis is an acute systemic (rapid, multi-system) and severe allergic reaction Anaphylactic shock—will usually lead to death in minutes if left untreated

Answer 67

Symptoms of anaphylaxis are related to the action of IgE and other anaphlatoxins, which act to release histamine and other signaling substances In addition to other effects, histamine induces vasodilation of arterioles and constriction of bronchioles in the lungs – also known as bronchospasm (constriction of the airways) May occur in response to venom or antivenom!

Answer 68

A solvent is a liquid at room temperature used to dissolve other substances examples like alcohol, glycols, aldehyde, ketones

Answer 69

Solubility Non-flammability/ Flammability/ Explosivity Volatility Metabolism Complex mixtures

Answer 70

Inhalation Absorption -skin -mucous membranes Ingestion Injection

Answer 71

Solvent exposure affected by airborne concentration, solubility, and exposure frequency. Higher vapor concentrations for enclosed spaces with poor ventilation, and with solvents having a high vapor pressure. When inhaled, lipid-soluble solvents will easily enter the blood Solvents also can pass through the skin, although not usually a significant route of exposure. Solvents often de-fat or irritate the skin.

Answer 72

-Toxic effects of solvents include: depression of the central nervous system, and irritation of membranes and tissues. -CNS depression tends to increase as the length of the carbon chain increases. --Molecules with more than 5 carbons generally are not volatile enough to cause hazardous exposures. -CNS-depressant properties are increased with the addition of halogens and alcoholic functional groups: alkanes

Answer 73

All organic chemicals can cause tissue irritation. -Solvents can extract lipids from cell membranes, casing irritation and cell damage. As the molecular size increases, the potential for irritation increases In general, irritation increases with the addition of functional groups Unsaturated compounds are stronger irritants than their saturated counterparts

Answer 74

Chemical hepatitis, with transaminases indicating hepatocellular injury Steatosis (fatty liver), occasionally progressing to hepatic necrosis Possible cirrhosis on recovery Reduced metabolism of other xenobiotics ? Acetylcysteine Mechanisms of hepatotoxicity -free radical formation -Halogenated hydrocarbons have greatest toxicity carbon tetrachloride, chloroform >> 1,1,1-trichloroethane, trichlorethylene >> non halogenated hydrocarbons

Answer 75

Acute tubular necrosis -acute heavy exposure -halogenated HCs, glycols, toluene, petroleum distillates Glomerulonephritis -chronic, long term exposure -gasoline implicated

Answer 76

General anesthesia-like activity or selective inhibition narcosis euphoria agitation (disinhibition) dyscoordination, ataxia, dysarthria

Answer 77

It is a chlorinated hydrocarbons TCE is a widely used solvent for metal degreasing At high acute exposure TCE can cause respiratory depression and cardio toxicity There is a weak association between TCE exposure and multiple myeloma, Hodgkin disease and cancers of the prostate, skin and cervis The IARC concluded that TCE is “probably carcinogenic to humans” based on its assessment of sufficient evidence in animals and limited evidence in humans

Answer 78

TCE contamination in ground water can release TCE vapors to the subsurface At many sites these vapors may then enter buildings from below, similar to radon Indoor air concerns may lead to cleanup of groundwater not considered a current or potential drinking water source (e.g., water table aquifers), and therefore not subject to drinking water regulations There is no single regulatory standard set by rulemaking for TCE in air

Answer 79

With rare exceptions, the toxicities associated with TCE are thought to be mediated by metabolites rather that by the parent compound The majority of TCE undergoes oxidation via cytochrome P450s, with a small proportion being conjugated with GSH via glutathione transferases

Answer 80

The human relevance of TCE induced rodent tumor is an unresolved issue For liver tumors: humans appear to be similar to rats than mice in the oxidative metabolism capacity For kidney tumors evidence exists that the rat have a greater GSH metabolism capacity With regards to lung cancer, the CYP450 content and the number of Clara Cells in the human lung are but a fraction of those in the mouse Based on the above, it appears that direct extrapolation from rodent data would overstate human TCE cancer risk

Answer 81

they are organic solvents and halogenated hydrocarbons Carbon tetrachloride, CCl4 --Strong CNS depressant --Potent liver toxin -----Acute exposure can cause death ------Chronic exposure can cause cirrhosis Chloroform, CHCl3 --CNS depressant --High exposure levels can cause liver and kidney damage and cardiac arrhythmias.

Answer 82

-Vinyl chloride , CH2CHCl --Skin irritant with CNS depressant properties --Much industrial hygiene concern over this chemical is due to its carcinogenic potential -----Chronic exposure may result in liver cancer (angiosarcoma) and other cancers as well.

Answer 83

Methvlene chloride, CH2Cl2 Not as toxic as the other chlorinated methanes A suspected carcinogen An excellent solvent Widely used in industry The 1997 OSHA methylene chloride standard should result in a reduction in the use of this chemical.

Answer 84

organic solvent aromatic hydrocarbon Benzene has been used for many industrial purposes, component of gasoline High exposure levels can cause death by CNS depression or cardiac arrhythmias Skin exposure causes dermatitis Inhalation of high concentrations may result in bronchial irritation or pulmonary edema. Chronic exposure causes blood disorders of aplastic anemia and leukemia. Victims of chronic benzene poisoning usually have a red blood cell count that is only 50% of normal.

Answer 85

organic solvent alkyl benzene Alkyl benzenes include toluene, xylenes, etc. More powerful narcotic effect than benzene Not known to cause blood disorders

Answer 86

organic solvent alcohol Irritant and a depressant The toxicology of this compound is well know through centuries of voluntary ingestion It does not have the neurotoxic properties of methanol

Answer 87

organic solvent alcohol Methanol, CH3OH (wood alcohol, methyl alcohol) Common industrial solvent Methanol poisoning may result in blindness, other neurological damage, or death. -Methanol poisoning 8 - 36 hrs after ingestion -Caused by compounds produced by methanol metabolism -Inhibited by administering ethanol

Answer 88

Mechanism of toxicity Methanol slowly metabolized to formaldehyde Formaldehyde rapidly metabolized to formic acid -Acidosis -Ocular toxicity

Answer 89

Fomepizole (4-methylpyrazole) Inhibits alcohol dehydrogenase Produces same end result as ethanol without causing intoxication

Answer 90

Antifreeze (95% ethylene glycol) Tastes sweet Kids, animals like taste/drink large quantities

Answer 91

Mechanism of toxicity Metabolized via alcohol dehydrogenase to glycoaldehyde then to glycolic , glyoxylic, and oxalic acids Acids lead to anion gap metabolic acidosis Oxalate binds with calcium -Forms crystals causing tissue injury -Produces hypocalcemia

Answer 92

Overdose Presentation (first 3-4 hours) Patient may appear intoxicated Gastritis, vomiting Increase in osmolar gap No initial acidosis Overdose Presentation (after 4-12 hours) Anion gap acidosis Hyperventilation Seizures, coma Cardiac conduction disturbances, arrhythmias Renal failure Pulmonary, cerebral edema

Answer 93

Lavage if within 2 hours Sodium bicarbonate Fomepizole or ethanol Folic acid, pyridoxine, thiamine (enhance metabolism of glyoxylic acid to nontoxic metabolites)

Answer 94

organic solvents -Aldehydes are strongly irritating to mucous membranes Can cause CNS depression, but their irritating nature usually prevents significant exposure. -Formaldehyde is regulated by OSHA as a carcinogen. -Can cause sensitization in about 4 - 8% of the population. -Glutaraldehyde --Commonly used in hospitals to sterilize endoscopes and other equipment --Also causes sensitization.

Answer 95

organic solvents CNS depressants Irritating effects cause workers to avoid high exposures -Toxic properties of ketones generally increase with increasing molecular weight. Acetone, (2-propanone) is a relatively safe solvent, as its principle toxic effect is irritation.

Answer 96

Organic solvents Anesthetic effect of ethers increases with the size of the molecule Very flammable, and they can be easily oxidized to explosive peroxides. Ethyl ether, CH3CH2OCH2CH3 (diethyl ether) Had been widely used as an anesthetic

Answer 97

Phenols are extremely irritating, capable of causing severe burns from direct contact. Phenol is cytotoxic to all cells and tissues, and is toxic by all routes of exposure -Rapidly absorbed through the skin -Fatalities have resulted within 10 minutes of skin exposure.

Answer 98

Delayed contact sensitivity aka allergic contact dermatitis standard chemistry for sensitizers -low molecular weight (haptens) -react with cutaneous proteins poison ivy and poison oak develops after one or more contacts subsequent exposure elicits response dependent on dose 3-5 weeks to develop skin reactivity

Answer 99

nettles -hollow, stinging hairs inject chemical into skin -mixture of acetylcholine, histamine, and serotonin causes local vasodilation, sweating and pain recovery in 3-5 days

Answer 100

parsnips, caraway, dill, parsley and citrus sensitize skin to long-wave UV light contain furocoumarins skin burns within 6-24 hours of contact range from mild irritation to severe blistering relieved with aspirin or corticosteroids

Answer 101

spurges, buttercups and wild pepper resembles contact with corrosive acid affected by dose, exposure time, genetics, temperature and humidity serious eye damage possible keratoconjunctivitis with transient blindness

Answer 102

Direct stomach irritation - Nausea, vomiting and diarrhea California buckthorn (sacred bark), tung nut, horse chestnut (active is called esculin), pokeweed Antimitotic (stops cell division) – Nausea, vomiting, confusion, delirium Lily family, glory lily, crocus, may apple Colchicine (gout treatment) Lectin toxicity – nausea, diarrhea, headache, confusion, dehydration, death Wisteria, castor bean (Ricinus communis) Ricin – block protein synthesis very toxic 5 to 6 beans can kill a child

Answer 103

Digitalis like glycosides – cardiac arrhythmias Foxglove (Digitalis purpurea), squill, lily of the valley Contain glycosides that are similar to digitalis The toxic effects is identical to that of Digitalis toxicity: nausea, vomiting and cardiac arrhythmias

Answer 104

Mistletoe (berries contain toxin) Cardiovascular Toxin is called phoratoxin (produces hypotension, bradychardia, negative ionotropic effects and vasoconstriction of the vessels of skin and skeletal muscle) Claviceps purpurea (ergot) is a fungus parasitic on grains of rye- this has caused an outbreak in several European countries in the Middle ages known as “Saint Anthony’s fire”.

Answer 105

Heart nerves – decreased heart rate and blood pressure, general weakness Lily, hellebore, death camas, heath family, monkshood, rhododendron Alkaloids, aconitum, grayanotoxin (concentrated in honey) (honey poisoning) It consists of marked bradbradycardia, hypotension, weakness, GI upset and in severe cases respiratory depression The toxins gets into the honey from the nectar collected by the bees from the flowers (Rhododendrom ponticum)

Answer 106

Water Hemlock, mint family

Answer 107

Excitatory Amino Acids – headache, confusion, hallucinations Red alga (produces Kainic acid), Green alga (produces domoic acid). In 1987 there was a serious outbreak in Canada in individual eating mussels containing domoic acid) coffee bean, tea, cola nut, caffeine most widely consumed stimulant in the world

Answer 108

very excitable, muscle weakness, death locoweed

Answer 109

Poison hemlock (Conium maculatum) Coniine – neurotoxic alkaloid – Poison used by Socrates

Answer 110

demyelination of peripheral nerves is caused by Buckthorn, coyotillo, tullidora (U.S., Mexico)

Answer 111

dry mouth, dilated pupils, confusion, hallucinations, memory lose Solanaceae family – jimsonweed, henbane, deadly nightshade (Atropa belladonna), angles trumpet (atropine and scopolamine)

Answer 112

mild stimulation to muscle paralysis, respiratory failure (curare), death Coffee bean, tea, cola nut Tobacco – South American – Strychnos family (curare) Blue green alga (anatonin A)

Answer 113

Hepatitis” and cirrhosis of liver - From contaminated grain Ragwort or groundsel Pyrrolizidine alkaloids – attack liver vessels – effects humans, cattle but some species resistant Liver failure and death Mushrooms – “Death cap” (Amanita phalloides) Amatoxin and phalloidin effects RNA and protein synthesis Liver cancer Fungus that grows on peanuts, walnuts, , etc…plant Alfaltoxins– produced by fungus in poorly stored grain

Answer 114

Teratogen – malformations in offspring (sheep) Veratrum californicum – native to North America Veratrum – blocks cholesterol synthesis – seen offspring of mountain sheep Abortifacients Legumes (Astrogalus) Bitter melon seeds (Momordica) Swainsonine toxin – stops cell division Lectins - halt protein synthesis– used by humans

Answer 115

through interference with RNA polymerase II, prevents the transcription of DNA

Answer 116

are rapid-acting and interrupt actin polymerization, impair cell membrane function, has limited absorption

Answer 117

Toxicity is due to gyromitrin which is metabolized to monomethylhydrazine This metabolite reacts with pyridoxine resulting in inhibition of pyridoxal phosphate-related enzymatic reactions

Answer 118

Headache, nausea, vomiting, seizures, and hepatorenal failure Symptoms occur 6-10 hours after ingestion Toxin may be eliminated with cooking but inhalation of cooking fumes may cause poisoning

Answer 119

Pyridoxine, in dose of 25 mg/kg

Answer 120

no lethality, Small amounts of muscarine are in Amanitia muscaria Symptoms: SLUDGE within 0.5-2 hours Salivation, Lacrimation, Urination, Diaphoresis, Gastrointestinal motility, Emesis Therapy: Atropine

Answer 121

Rarely fatal Coprine has a disulfiram like effect(Blocks acetaldehyde dehydrogenase) Toxic if alcohol is consumed within 48-72 hours after mushroom Symptoms: Flushing, headache, hypotension, histamine induced vasodilation Therapy: Supportive, anti H1 and anti H2, prostaglandin inhibitors

Answer 122

Antiinflammatory effects mediated by ability to inhibit microtubule and PMN activity May cross placenta + found in breast milk

Answer 123

a potent cytotoxin (toxic at cellular level) concentrated in the castor bean also contains highly toxic glycoproteins that block the synthesis of other good proteins causing cell death used as a lubricant, boiling makes it non- toxic

Answer 124

Intravenous-Introduced into a puncture or cut. Inhalation- Aerosolized liquid or powder inhaled directly into the lungs. Ingestion- Ricin enters through contaminated food or water into the stomach. Symptoms range from fever, cough, nausea, chest tightness, sweating, cyanosis, hypo tension (very low blood pressure), dyspnea (labored breathing). Circulatory and respiratory collapse occur within 36-72 hrs leading to death.

Answer 125

Death from Castor beans is caused by two lectins in the beans: Ricin I and Ricin II (more toxic) Ricin II consists of two chains of amino acids. The A chain inactivates the 60s ribosomal subunit of cells by depurination of a single adenosine residue within the 28s rRNA and blocks protein synthesis Exposure to high or very warm temperatures and or high humidity will diminish the strength of the toxin (denaturing effect).

midterm Flashcards

(149 cards)