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Basic Safety Rules Use common sense. No unauthorized experiments. 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, Consumer Product Safety Commission • Worker OSHA • Environment EPA Chemical Stewardship
Government Regulation worker OSHA environment EPA The government regulates chemicals to protect the… FDA USDA FAA CPSC consumer
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 Karen Wetterhahn, a chemistry Professor at Dartmouth College, died of mercury poisoning after spilling just one drop in a laboratory on Aug. 14, 1996. The mercury penetrated her skin through gloves. LYME, N. H. (AP) — It was just a drop of liquid, just a tiny glistening drop. It glided over her glove like a jewel. Scientist Karen Wetterhahn knew the risks: The bad stuff kills if you get too close. She took all the precautions working with mercury in her Dartmouth College lab — wearing protective gloves and eye goggles, working under a ventilated hood that sucks up chemical fumes. So on that sunny day in August, when she accidentally spilled a drop, she didn't think anything of it. She washed her hands, cleaned her instruments and went home. It was just a drop of liquid, just a tiny glistening drop. At first, friends thought she had caught a stomach bug on her trip to Malaysia. It wasn't until she started bumping into doors that her husband, Leon Webb, began to worry. Karen, always so focused, always so sure of her next step, was suddenly falling down as if she were drunk. In 15 years together, she had never been sick, never stopped working, never complained. Leon was stunned when she called for a ride home from work. Over lunch a few days later, Karen confided to her best friend, Cathy Johnson, that she hadn't felt right for some time. Words seemed to be getting stuck in her throat. Her hands tingled. It felt like her whole body was moving in slow motion. "Karen, " Johnson said as she drove her back to the college, "we've got to get you to the hospital. " "After work, " Karen promised, walking unsteadily into the Burke chemistry building for the last time. That night, Leon drove her to the emergency room. It was Monday, Jan. 20, 1997, five months since she had spilled the drop in the lab. Just a single drop of liquid. Yet somehow it had penetrated her skin. By the weekend, Karen couldn't walk, her speech was slurred and her hands trembled. Leon paced the house. "Virus" seemed an awfully vague diagnosis, for symptoms that were getting worse every day. "It's mercury poisoning, " Dr. David Nierenberg said. "We have to start treatment immediately. " Leon hung up with relief. At last, they understood the problem. Now maybe they could fix it. It seemed impossible to believe that anything could be wrong with Karen Wetterhahn, one of those quietly impressive individuals whose lives seemed charmed from the start. Serious and hardworking, she excelled at every thing she turned to — science or sailing or skiing. She grew up near Lake Champlain in upstate New York in a family so close that when she and her only sister became mothers, they named their daughters after each other: Charlotte and Karen was always the brilliant one of the family, the one who would do great things. And she did, becoming the first woman chemistry professor at Dartmouth, running a world-renowned laboratory on chromium research, devoting herself to her work. It was important work, the kind that could lead to cures for cancer and AIDS. Karen thrived on it. She loved nothing more than experimenting with a chemical, figuring out its bad side and how it breaks down living things.
Lead Poisoning (Plumbism) LD 50 = 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. 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. GLOVES This symbol is to remind you to wear gloves to protect your hands from contact with corrosive substances, broken glass, or hot objects. 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. . 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. 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. EXPLOSION This symbol indicates that the potential for an explosive situation is present. When you see this symbol, read the instructions carefully and follow them exactly. . POISON This symbol indicates the presence of a poisonous substance. Do not let such a substance come in contact with your skin and do not inhale its vapors. ELECTRICAL SHOCK This symbol indicates that the potential for an electrical shock exists. Read all instructions carefully. Disconnect all apparatus when not in use. 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 laboratory 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 Caustic Substance Waste Disposal
Safety Equipment Safety Goggles Fire Extinguisher Type A Type B Type C Safety Shower
Chemical Burns Flammable Health Reactive Special 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
Material Safety Data Sheet (MSDS) • Gives information about a chemical. • Lists “Dos” and “Don’ts. ”
Chemical Exposure acute exposure a one-time exposure causes damage chronic exposure damage occurs after repeated exposure
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 toxicity time – Acute toxicity: immediate effect of a substance as a result of toxicity a single dose • “Lethal Dose 50%” LD 50
Toxicity Which is more toxic? http: //lansce. lanl. gov/training/FST 2004/images 04/chemicals 1. gif
Toxicity Which is more toxic? Chemical A: LD 50 = 3. 2 mg/kg Chemical B: LD 50 = 48 mg/kg Chemical A is more toxic because less of it proves fatal to half of a given population.
LD 50 the lethal dosage for 50% of animals on which the chemical is tested There are various ways an LD 50 can be expressed. For example, acetone has the following LD 50 s: ORL-RAT LD 50: IHL-RAT LD 50: SKN-RBT LD 50: 5, 800 mg/kg 50, 100 mg/m 3 -h 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