MSDSMaterial Safety Data Sheets • How toxic is that chemical? • If a child swallows it, what do I do? • A Pakistani woman recently drank household bleach to avoid an arranged marriage, how much bleach is fatal? • MSDS sheets provide many answers, our project for this dry lab experiment
Material Safety Data Sheets • Required for chemicals used in commerce • Many listings from suppliers http://sciencelab.com/ • Standard format in 15 parts • NPFA diamond with values for health, fire, reactivity • (1-2) Identification, Composition • (3-4) Hazards identification, First Aid measures • (5) Fire & explosion risk • (6) Accidental release measures • (7-8) Handling and storage, Exposure controls • (9-10) Physical and chemical properties, reactivity • (11) Toxicology, LD50, LC50 • (12-15) Ecology, disposal, transport, regulatory.
LD50, LC50 • A measure or index of toxic risk • The dose when 50% of population dies • LD50 measurement is exposure by mass • Ingestion most common, also injection • Mg of poison per kg of victim, mg/kg • LC50 is a gas or liquid exposure measure • Concentration of poison, usually mg/liter • Exposure could be inhalation, skin contact
LD50 details • Definition for LD50 • mg/kg = Milligrams of poison per kilogram of victim • Small number is poison, large number is victim mass • Some materials hazardous in small (mg) amounts • Nicotine 125 mg/kg (rat) • Polonium 0.00001 mg/kg • Why mice? • Immoral and illegal to use people for experiments • Nazi war crimes, Dr. Josef Mengele “angel of death” • See book, Macht Ohne Moral • Mammals have similar sensitivities to many poisons • Small animals easy to raise, mature quickly • Mice, rats, rabbits are common test subjects
Don’t experiment on people!Josef Mengele pursued as a war criminal for doing that
A leap of faith • We ASSUME human equivalency • Equivalent poison/victim mass ratio • Not always true, mouse ≠ rabbit data • Metabolism, tolerances can differ • Rasputin ate cyanide, shot 3x, then shot 4x • For Caffeine (section 2, 11) oral LD50 • 192 mg/kg [rat] • 127 mg/kg [mouse] • 224 mg/kg [rabbit] • Which best applies to humans ? • Consider mammal size, diet/metabolism • Safest to use smallest numerical value
Application to Humans Liquor Example • Ethanol LD50 = 3,450mg/kg (mouse) • For a 70 kilogram person (154 pounds) • Poison at 3400 mg/kg, victim weighs 70 kg • 3,450mg/kg*70kg = 241,500 mg = 241 gm alcohol • 50% alcohol in whiskey 241/0.5 = 482 gm • 482gm /0.915 gm/ml = 526 mL (70% of 750 mL bottle) • 12% alcohol wine 241/0.12= 2,008 gm (≈2 liter) • 5% alcohol beer 241/0.05=4820 gm (≈5 liters) • 355 mL per 12 oz, 5 liters = 13.5 cans or 2.3 6-packs
Sodium Hypochlorite NaOCl, 5% solution Often sold at 6% LD50 = 13gm/Kg (rat) 120 lb person ≈ 55kg 13g/kg*55kg = 715g Density ≈ 1.1g/mL Volume = 650mL or about 7/10 quart ! Household Bleach, MSDSan arranged Pakistan marriage resulted in suicide
Pakistan village where Shafilea drank bleach to avoid an arranged marriagehttp://www.telegraph.co.uk/news/uknews/crime/9449488/The-Pakistan-village-where-Shafilea-drank-bleach-to-avoid-an-arranged-marriage.html
Acetaminophen is active pain reliever ingredient Standard dose 325mg LD50 338 mg/kg mouse 70 kg person 23.7 gram LD50 1944 mg/kg rat 70 kg person 136 gram “Extra Strength” 500mg, or 0.50gram, reaches 24 gram level at 48 tablets Tylenol in the newsreports of illness and deaths resulted in new warning label
Used in over 600 products Overdoses linked to >500 deaths Generally safe to use as prescribed Do not use with alcoholic drinks New warning label for 2013 due to overdose liver damage For adults the recommended dose of acetaminophen is 650 to 1000 mg every 4 to 6 hours as needed, not to exceed 4000 mg in 24 hours. Some adult products (Extra Strength TYLENOL) are not intended for use in children under 12 years of age. Acetaminophen (Tylenol) http://www.nsf-rs.org/media/downloadable/files/msds/acetaminophen_msds.pdf
Common allergy pill • Acrivastine • LD50: 2500 mg/kg (mice, 2 month expose) • Dosage 8 mg • Used in treatment of allergies and hay fever. Blocks histamine receptors in body. http://www.rxlist.cosemprex-d-drug.htm
Benadryl and Semprex are trade names for antihistamine Acrivastine, 8 mg dose http://www.rxlist.com/semprex-d-drug.htm
Another common allergy remedy • Cetirizine • LD50 2,000 mg/kg(mice, 2 month expose) • Dosage 20 mg • Antihistamine commonly used for allergies, and hay fever symptoms
Zyrtec is one of several brand names for Cetirizine, 10 mg per pill http://www.rxlist.com/zyrtec-drug.htm http://www.rxlist.com/semprex-d-drug.htm
Common fungal remedies • Clotrimazole • LD50 900 mg/kg (mice, 2 month expose) • Dosage 10 mg • Anti fungal medication used for vaginal yeast infection, ringworm, thrush, athlete’s foot.
Mycelex, Lotrimin are brand names for anti-fungal agent clotrimazole, dose 10mg http://www.rxlist.com/mycelex-drug.htm
Terbinifine hydrochloride LD50 20,000 mg/kg 250 mg dose (oral) Antifungal agent, internal and external Lamasil Antifungal
Lamisil anti-fungal http://www.rxlist.com/lamisil-drug.htm
Common allergy remedies Loratadine LD50 = 50 mg/kg(mice, 2 month expose) 10 mg/tablet Antihistamine for allergies. Chemically related to anti-depressant and anti psychotic drugs.
Claritin is brand name for Loratadine http://www.rxlist.com/mycelex-drug.htm
How dangerous are these? • Assume 154 pound (70 kg) person • How much for 50% risk of death?
“Mad Monk” Rasputin murdered 1916 Given enough Cyanide to kill 5 people Stabbed with entrails hanging out Shot and clubbed into submission Shot 4 more times by assassins Tied up and wrapped in a carpet Thrown into icy Niva River Escaped from carpet and bonds Autopsy cause of death …. Drowning ! You could be more sensitive than others, or maybe like Rasputin. MSDS values are only a guideline, be careful. Not all people have same sensitivityGrigori Rasputin, Russian mystic and confidant to the Tsars
What about herbicides?Tough on plants, “Roundup” very commonly used, low riskbest to wear gloves, note dermal (skin absorption) risk, “G” = general usehttp://pubs.cas.psu.edu/freepubs/pdfs/uo222.pdf (for a long list)
InsecticidesMalathion in aerial spray used to combat fruit-fly infestationskin absorption more dangerous than ingestion?, “R”=restricted use
Why use Malathion? • Malathion is a pesticide that is widely used in agriculture, residential landscaping, public recreation areas, and in public health pest control programs such as mosquito eradication. In the US, it is the most commonly used organophosphate insecticide. • Malathion was used in the 1980s in California to combat the Mediterranean Fruit Fly. This was accomplished on a wide scale by the near weekly aerial spraying of suburban communities for a period of several months. Formations of three or four agricultural helicopters would overfly suburban portions of Alameda County, San Bernardino County, San Mateo County, Santa Clara County, San Joaquin County, Stanislaus County, and Merced County releasing a mixture of malathion and corn syrup, the corn syrup being a bait for the fruit flies. Malathion has also been used to combat the Mediterranean fruit fly in Australia. • Malathion was sprayed in many cities to combat West Nile virus. In the Fall of 1999 and the Spring of 2000, Long Island and the five boroughs of New York City were sprayed with several pesticides, one of which was malathion. While it was claimed by some anti-pesticide groups that use of these pesticides caused a lobster die-off in Long Island Sound, there is as of yet no conclusive evidence to support this.
B.T. Collins’ Malathion cocktaila potentially dangerous publicity stunt
Hazardous Materials, NFPA-704 DiamondSymbol in white for specifics (radioactive, don’t use water, etc.) Firemen might NOT enter area with danger value >2
LC50 • Lethal Concentration, kills 50% population • Applies to liquids & gaseous poisons • Termite tenting of house • “Bug Bombs” • Insecticides • War gases (Chlorine, “nerve gas”) • May have skin exposure, inhalation values • Expressed in various concentration units • Milligrams poison per liter of air • Micrograms poison per cubic meter of air
grams of poison per liter of gas or liquid Insecticides Nerve gas Cyanide (Zyklon B) Carbon Monoxide WWI chlorine LC50 examples
Sarin, or GB, is an organophosphorus compound with formula [(CH3)2CHO]CH3P(O)F. It is a colorless, odorless liquid, used as a chemical weapon due to extreme potency as a nerve agent. It is classified as a weapon of mass destruction in UN Resolution 687. Production and stockpiling of sarin is outlawed by the Chemical Weapons Convention of 1993. Sarin can be lethal even at very low concentrations, with death following within one minute after direct ingestion due to suffocation from lung muscle paralysis, unless some antidotes,typically atropine or Biperiden and pralidoxime, are quickly administered to a person. People who absorb a non-lethal dose, but do not receive immediate medical treatment, may suffer permanent neurological damage. Sarin nerve gasrecently released in Syria civil war
Sarin attacks nervous system by stopping nerve endings in muscles from switching off. Death will occur as a result of asphyxia due to the inability to control the muscles involved in breathing function. Sarin is a potent inhibitor of acetylcholinesterase, an enzyme that degrades the neurotransmitter. Acetylcholine is the neurotransmitter used at the neuromuscular junction, where signals are transmitted between neurons from the central nervous systems to muscle fibres. Normally, acetylcholine is released from the neuron to stimulate the muscle, after which it is degraded by acetylcholinesterase, allowing the muscle to relax. A build-up of acetylcholine, means the neurotransmitter continues to act on the muscle fibre, so that nerve impulses are continually transmitted. Its mechanism of action resembles some commonly used insecticides, such as malathion. In biological activity. It resembles carbamate insecticides, such as Sevin, and medicines including pyridostigmine, neostigmine, and physostigmine. How Sarin works
Sarin Exposurehigh levels kill in minutes, low levels cumulative over time http://www.cdc.gov/niosh/ershdb/EmergencyResponseCard_29750001.html
Go to http://sciencelab.comclick on “chemical MSDS” Listing.A list of chemical MSDS also on Jaguar
Chem 32A MSDS Experiment 2 • Worksheets in Lab Manual • Questions • Calculations involving MSDS • We are interested in sections 9-11 hazards • Everybody does Sugar and Salt • Two items YOU choose, select here or at home • Look up data on web for items at home • Medications, garden products, household chemicals • Don’t forget cover sheet with your review