All generators of hazardous waste are required to follow specific rules and regulations regarding labeling, storage, and disposal of laboratory chemical waste. The Science Center is a Small Quantity Generator (SQG) in that we generate less than one thousand pounds of hazardous waste and less than 2.2 pounds of acutely hazardous waste per month. There are lists of each kind of waste in the Science Center Office and in the stockroom. As a SQG we are allowed to store waste for up to six months before disposal.
Satellite Accumulation Area: an area as close as possible to the point of waste generation. This area can be part of the hood space of a teaching or research laboratory. When the waste container is filled it must be dated and removed within three days.
Waste Accumulation Area: an area where waste is stored for up to six months before disposal. The waste accumulation area for the Science Center is the shed on the loading dock.
Labelling: All waste containers (usually one gallon plastic-coated bottles) must be labeled with the name of all constituents of the waste in English (no chemical formulas allowed), the percentage of each component, the hazards of the material (flammable, corrosive, poison, or reactive), and the words "Hazardous Waste" in one inch high letters. The proper labels are available in the stockroom.
Pickups: When a container is 80% full call Harry Clark in the stockroom (x 3133) to arrange for removal.
Unknowns: Complete unknowns will need to be analyzed by the disposal company, at extra expense, before they can be removed.
General Rules: Unlabelled or incompletely labelled material cannot be taken. In addition, all waste containers must be securely capped except when adding materials to the bottle. This is always the most frequent complaint when Environmental Protection Agency or Department of Environmental Protection inspects laboratories.
Acrylamide is often used for separation of protein and nucleic acids according to size by electrophoresis and is a suspected carcinogen and a known neurotoxin.
Handle unpolymerized solutions of Acrylamide with great care. Wear lab coat, gloves and safety goggles and coat your lab bench with absorbent bench paper. Avoid any contact of Acrylamide solutions or polyacrylamide gels with skin. To avoid handling powdered Acrylamide, purchase premixed solutions when possible. If a powder must be used, it should be handled in a chemical fume hood using an electric or beam balance. It is recommended that the user wear a dust mask to avoid inhalation when working with the powder. OSHA regulations specify that certain requirements be met before purchasing masks. Respirators
Acrylalmide solutions and polyacrylamide gels should be disposed of as chemical waste and never put down the drain. Label waste and call the stockroom to arrange for pickup.
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Formaldehyde and Formalin, commonly used as fixatives and as nucleic acid denaturants, are suspected carcinogens. The OSHA Permissible Exposure Limit is 1 PPM in an eight hour time weighted average. Approximately 1.5 grams of vaporized Formaldehyde will achieve this concentration in a typical laboratory (not accounting for air flow). The odor threshold of formaldehyde is reported to be as low as 0.1 ppm.
Health - A suspected carcinogen. Must be used in a Designated Area. (This area can be part of a lab or fume hood, but must be labeled as the Designated Area).
- Eye, nose, throat, and upper respiratory system irritant - Strong.
- Skin contact irritant - Strong
- Flammability - Moderate.
- Reactivity - Severe with strong oxidizing agents, strong acids, strong bases, alkali metals, amines and ammonia, phenol, and strong reducing agents.
Required Protective Equipment
Wear goggles, face shield, lab coat, vinyl apron and neoprene gloves. Place all breakable containers in an approved bottle carrier for transport. Always work inside a fume hood. Transfer the required amount of formaldehyde into a secondary measuring beaker, and immediately close the container. Return the formaldehyde container to the solvent cabinet.
Hot Solutions of formaldehyde containing agarose should be handled in the chemical fume hood; gels should be poured and allowed to set in the hood. It is preferable to run formaldehyde gels inside the chemical hood, but they can be run on the bench in enclosed gel boxes when necessary. A recent report has suggested that it may not be necessary to include formaldehyde in the gel in order to get an accurate molecular weight determination of RNA. Inclusion of formaldehyde as a denaturant to the sample buffer could be sufficient (Biotechniques 9:558). If you can adopt this procedure, the use of significant quantities of formaldehyde could be greatly reduced. Please evaluate it for acceptability in your lab.
September 16, 2011t screw-cap container and labeled correctly before notifying the stockroom for pickup.
Accidental Exposure or Spills
If eye contact occurs, flush with cold water for 15 minutes, and obtain medical attention. If skin contact occurs, flush with cold water. If shoes or clothing become contaminated, remove them under an emergency shower and discard or wash thoroughly before wearing again. If spills occur inside the hood, absorb the material with the spill kit, and place the waste in a sealable container. If a spill occurs outside the hood, evacuate the lab and call for help.
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NOTE: Prior approval is needed to use Benzene at Wellesley College Science Center. Contact Harry Clark or Administration for application.
When possible, use a substitute of benzene.
Substance: Benzene (Benzol)
BI 80.1°C, 5.5°C
Slightly soluble in water (0.18 g/100 mL)
"Paint-thinner like" odor detectable at 12 ppm
PEL (OSHA) 1 ppm (3.2 mg/m3)
TLV-TWA (ACGIH) 10 ppm (3.2 mg/m3)
STEL (ACGIH) 5 ppm (16 mg/m3)
Highly flammable; chronic toxin affecting the blood-forming organs; OSHA "select carcinogen".
Storage and Handling
Because of its carcinogenicity and flammability, benzene should be handled using the general laboratory procedure described in the Chemical Hygiene Plan. In particular, work with benzene should be conducted in a fume hood to prevent exposure by inhalation, and splash goggles and impermeable gloves should be worn at all times to prevent eye and skin contact. Benzene should be used only in areas free of ignition sources.
In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally). If chloroform is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once by calling x3000. In the event of a spill, remove all ignition sources and call x3133.
Excess Benzene and waste material containing this substance should be placed in an appropriate container and clearly labelled. Call Harry Clark at 3133 to arrange a pick-up.
The acute toxicity in benzene is low. Inhalation of benzene can cause dizziness, euphoria, giddiness, headache, nausea, drowsiness, and weakness. Benzene can cause moderate irritation to the skin and severe irritation to eyes and mucous membranes, Benzene readily penetrates the skin to cause the same toxic effects as inhalation or ingestion.
The chronic toxicity of benzene is significant. Exposure to benzene affects the blood and blood-forming organs such s the bone marrow, causing irreversible injury; blood disorders including anemia and leukemia may result. The symptoms of chronic benzene exposure may include fatigue, nervousness, irritability, blurred vision, and labored breathing. Benzene is regulated by OSHA as a carcinogen (Standard 1910.102) and is listed in IARC Group 1 ("carcinogens to humans"). This substance is classified as a "select carcinogen" under the criteria of the OSHA Laboratory Standard.
Flammability and Explosibility
Benzene is a highly flammable liquid (NFPA rating = 3), and its vapors may
travel a considerable distance to a source of ignition and "flask back". Vapor Air mixtures are explosive above the flash point. Carbon dioxide and dry chemical extinguishers should be used to fight benzene fires.
Reactivity and Incompatibility
Fire and explosion hazard with strong oxidizers such as chlorine, oxygen, and bromine (in the presence of certain catalysts such as iron) and with strong acids.
Substance: Chloroform (Trichloromethane) CAS 67-66-3
Bp 61°C, mp-63.5°C
Slightly soluble in water (0.8g/100 mL)
Ethereal, sweet odor detectable at 133 to 276 ppm (mean = 192)
160 mmHg at 20°C
Low acute toxicity; skin and eye irritant
Storage and Handling
Chloroform should be handled in the laboratory using the "basic prudent practices" described in general laboratory procedures. In addition, all work should be conducted in the fume hood.
In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 minutes (lifting upper and lower lids occasionally). If chloroform is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once by calling x3000.
Excess chloroform and waste material containing this substance should be placed in an appropriate container and clearly labelled. Call Harry Clark at 3133 to arrange a pick-up.
The acute toxicity of chloroform is low by all routes of exposure. Inhalation can cause dizziness, headache, drowsiness, and nausea, and at higher concentrations, disorientation, delirium and unconsciousness. Inhalation of high concentrations may also cause liver and kidney damage. Exposure to 25,000 pm for 5 min can be fatal to humans. Ingestion of chloroform is irritating to the skin and eyes, and liquid splashed in the eyes can cause burning pain and reversible corneal injury. Olfactory fatigue occurs on exposure to chloroform vapor, and it is regarded as a substance with adequate warning properties. Chloroform shows carcinogenic effects in animal studies. It is not classified as a "select carcinogen" according to the criteria of the OSHA Laboratory Standard. Prolonged or repeated exposure to this substance may result in liver and kidney injury. There is some evidence from animal studies that chloroform is a developmental and reproductive toxin. The OSHA permissible exposure limit is 50 ppm averaged over 8 hours.
Flammability and Explosibility
Chloroform is noncombustible. Exposure to fire or high temperatures may lead to formation of phosgene, a highly toxic gas.
Reactivity and Incompatibility
Chloroform reacts violently with alkali metals such as sodium and potassium,
and sodium hydroxide, potassium t-butoxide, sodium methoxide, and sodium
hydride. Chloroform reacts explosively with flourine and dinitrogen tetroxide.