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Safety. Basic Safety Rules. No unauthorized experiments. Use common sense. No horseplay. Handle chemicals/glassware with respect. Safety Features of the Lab. safety shower. fire blanket. fire extinguisher. eye wash. fume hood. circuit breaker switch. Government Regulation of Chemicals.
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Basic Safety Rules No unauthorized experiments. Use common sense. No horseplay. Handle chemicals/glassware with respect.
Safety Features of the Lab safety shower fire blanket fire extinguisher eye wash fume hood circuit breaker switch
Government Regulation of Chemicals The government regulates chemicals to reduce the risk to the… • Consumer FDA, USDA, FAA, Consumer Product Safety Commission • Worker OSHA Chemical Stewardship • Environment EPA Is this an appropriate role for government?
Thalidomide • Prescription drug for morning sickness • Drug can be made in two ways • Put together same material in more than one way. • A = “good” drug (stops morning sickness) • B = “bad” drug (birth defects) • Side-effect from “bad” drug • Stopped development in fetus • Short arms; “flipper-babies”
“Happy” & “Sad” Balls • Cis-isomer • Sad ball • Trans-isomer • Happy ball
Mercury Poisoning One tiny drop of mercury shatters lives and science LYME, N.H. (AP) — It was just a drop of liquid, That night, Leon drove her to the emergency just a tiny glistening drop. It glided over her glove room. It was Monday, Jan. 20, 1997, five months like a jewel. since she had spilled the drop in the lab. Scientist Karen Wetterhahn knew the risks: The Just a single drop of liquid. Yet somehow it had bad stuff kills if you get too close. penetrated her skin. She took all the precautions working with mer- By the weekend, Karen couldn't walk, her speech cury in her Dartmouth College lab — wearing pro- was slurred and her hands trembled. Leon paced the tective gloves and eye goggles, working under a house. "Virus" seemed an awfully vague diagnosis, ventilated hood that sucks up chemical fumes. for symptoms that were getting worse every day. So on that sunny day in August, when she acci- "It's mercury poisoning," Dr. David Nierenberg dentally spilled a drop, she didn't think anything of said. "We have to start treatment immediately." it. She washed her hands, cleaned her instruments Leon hung up with relief. At last, they understood and went home. the problem. Now maybe they could fix it. It was just a drop of liquid, just a tiny glistening It seemed impossible to believe that anything drop. could be wrong with Karen Wetterhahn, one of At first, friends thought she had caught a stomach those quietly impressive individuals whose lives bug on her trip to Malaysia. It wasn't until she seemed charmed from the start. started bumping into doors that her husband, Leon Serious and hardworking, she excelled at every - Webb, began to worry. Karen, always so focused, thing she turned to — science or sailing or skiing. always so sure of her next step, was suddenly falling She grew up near Lake Champlain in upstate New down as if she were drunk. York in a family so close that when she and her only In 15 years together, she had never been sick, nev- sister became mothers, they named their daughters er stopped working, never complained. Leon was after each other: Charlotte and Karen. stunned when she called for a ride home from work. Karen was always the brilliant one of the family, Over lunch a few days later, Karen confided to her the one who would do great things. And she did, be-best friend, Cathy Johnson, that she hadn't felt right coming the first woman chemistry professor atfor some time. Words seemed to be getting stuck in Dartmouth, running a world-renowned laboratoryher throat. Her hands tingled. It felt like her whole on chromium research, devoting herself to herbody was moving in slow motion. work. "Karen," Johnson said as she drove her back to It was important work, the kind that could lead to the college, "we've got to get you to the hospital." cures for cancer and AIDS. Karen thrived on it. She "After work," Karen promised, walking unsteadi- loved nothing more than experimenting with a ly into the Burke chemistry building for the last chemical, figuring out its bad side and how it breaks time. down living things. Karen Wetterhahn, a chemistry Professor at Dartmouth College, died of mercury poisoning after spilling just one drop in a labor- atory on Aug. 14, 1996. The mercury penetrated her skin through gloves.
Lead Poisoning(Plumbism) LD50 = mg / kg Small children may accidentally ingest lead-based paints that peel off from window sills and walls. Lead accumulates near bone joints – lighter color on X-ray is lead. Effects: slow mental development, lack of concentration
Safety Symbols SAFETY CLOTHING This symbol is to remind you to wear a laboratory apron over your street clothes to protect your skin and clothing from spills. DANGEROUS VAPORS This symbol indicates the presence of or production of poisonous or noxious vapors. Use the fume hood when directed to do so. Care should be taken not to inhale vapors directly. When testing an odor, use a wafting motion to direct the vapor toward your nose. SAFETY GOGGLES This symbol is to remind you that safety goggles are to worn at all times when working in the laboratory. For some activities, your teacher may also instruct you to wear protective gloves. EXPLOSION This symbol indicates that the potential for an explosive situation is present. When you see this symbol, read the instructions care- fully and follow them exactly.. GLOVES This symbol is to remind you to wear gloves to protect your hands from contact with corrosive substances, broken glass, or hot objects. POISON This symbol indicates the presence of a poi- sonous substance. Do not let such a substance come in contact with your skin and do not inhale its vapors. HEATING This symbol indicates that you should be careful not to touch hot objects with your bare hands. Use either tongs or heat-proof gloves to pick up hot objects.. ELECTRICAL SHOCK This symbol indicates that the potential for an electrical shock exists. Read all instructions carefully. Disconnect all apparatus when not in use. FIRE This symbol indicates the presence of an open flame. Loose hair should be tied back or covered, and bulky or loose clothing should be secured in some manner. RADIATION This symbol indicates a radioactive substance. Follow your teacher's instructions as to proper handling of such substances.. CORROSIVE SUBSTANCE This symbol indicates a caustic or corrosive substance - most frequently an acid. Avoid contact with skin, eyes, and clothing. Do not inhale vapors. DISPOSAL This symbol indicates that a chemical should be disposed of in a special way. Dispose of these chemicals as directed by your teacher. BREAKAGE This symbol indicates an activity in which the likelihood of breakage is greater than usual, such as working with glass tubing, funnels and so forth. HYGIENE This symbol is to remind you to always wash your hands after completing a labor- atory investigation. Never touch your face or eyes during a laboratory investigation.
Safety Symbols Eye Protection Required Heat Protection Clothing Protection Required Glassware Safety Hand Protection Required Laboratory Hygiene Chemical Safety Sharp Object Hazard Waste Disposal Caustic Substance
Safety Equipment Safety Goggles Fire Extinguisher Type A Type B Type C Safety Shower
Flammable Health Reactive Special Chemical Burns Chemical burns on feet. Skin burned by chemicals
DANGER Laboratory Safety Rules
SAFETY in the Science Classroom Obey the safety contract • Use common sense • No unauthorized experiments • Wear safety glasses • Safety is an attitude! • Don’t take anything out of lab • Read and follow all instructions • NO HORSE PLAY!
Material Safety Data Sheet (MSDS) • Gives information about a chemical. • Lists “Dos” and “Don’ts.”
acute exposure chronic exposure Chemical Exposure damage occurs after repeated exposure a one-time exposure causes damage
How Toxic is “Toxic?” Chemicals may cause harm in many different ways. • Flammable • Explosive • Radioactive • Corrosive • Irritant • Toxic • Chronic toxicity: low doses repeated over a long period of time • Acute toxicity: immediate effect of a substance as a result of a single dose • “Lethal Dose 50%” LD50
Toxicity Which is more toxic? http://lansce.lanl.gov/training/FST2004/images04/chemicals1.gif
Toxicity Which is more toxic? Chemical A: LD50 = 3.2 mg/kg Chemical B: LD50 = 48 mg/kg Chemical A is more toxic because less of it proves fatal to half of a given population.
LD50 There are various ways an LD50 can be expressed. For example, acetone has the following LD50s: the lethal dosage for 50% of animals on which the chemical is tested ORL-RAT LD50: 5,800 mg/kg IHL-RAT LD50: 50,100 mg/m3-h SKN-RBT LD50: 20 g/kg
Knowledge = Safety • Material Safety Data Sheet (MSDS) • Lists hazards, special handling instructions, and risks associated with a material. Supplied by manufacturer. • Acute Exposure • Single episode can cause great damage • Chronic Exposure • Many episodes over a period of time cause damage • Carcinogen – causes cancer • Mutagen – causes mutations (genetic defects) • Tetragen – causes birth defects • Neurotoxin – severely poisonous and toxic