GENERAL TERMINOLOGY
Group 2: Group 2: The agent (mixture) is probably carcinogenic to humans and Group 2A: The exposure circumstance entails exposures that are probably carcinogenic
to humans. Group 2B: The exposure circumstance entails exposures that are possibly carcinogenic to humans. Group 3: The agent (mixture, or exposure circumstance) is unclassifiable as to carcinogenicity in humans, Group 4: The agent (mixture, exposure circumstance) is probably not carcinogenic to humans.
Iridocyclitis: Iridocyclitis is an inflammation of the iris (the colored part of the eye) and of the ciliary body (muscles and tissue involved in focusing the eye).
This condition is also called "anterior uvetitis. 'I The condition can be marked by red eye, pain, photophobia (light sensitivity, literally "fear of light"), watering of the eyes and a decrease in vision. If only one eye is affected, shining light in the good eye can produce pain in the affected eye. This is closely related to conjunctivitis, swelling of the mucous membranes around the eye. Treatments
HAZARDS IN THE CHEMICAL PROCESS INDUSTRIES 47
include steroid, atropine, antibiotic or antiviral eyedrops. Exposure to chemicals that irritate the eyes (such as lachrymators) can cause iridocyclitis or aggravate an existing case. Seek medical treatment, if the condition does not clear up on its own. If you are not certain, whether a chemical was splashed in your eye or you are suffering from iridocyclitis, you should consult a physician immediately.
Ketosis: Ketosis is the presence of excess ketones in the body. Ketones are chemicals with a carbonyl unit (a carbon doubly bonded to an oxygen), that has two alkyl or aromatic (hydrocarbon) substituents, bonded to the carbon atom.
Ketones are a byproduct of fat metabolism (the breaking down of fat into energy). Normally, your body is efficient at removing these, but when certain enzymes are absent or damaged, the amount of ketones in the body can build up to dangerous levels. Certain individuals are predisposed towards ketosis. For example, those with diabetes have low insulin levels and can not process glucose (sugar) for energy. Therefore, their bodies break down fat, leading to a rise in ketone levels. Ketones can be excreted through the urine and those that are volatile (such as acetone) can be expelled through the lungs. Diabetics can be mistaken for being drunk by the odor on their breath, and acetone being expelled through the lungs can give a false positive result on early model breathalyzers.
However, don't expect to escape a ticket as driving while impaired (due to low blood sugar) is still a traffic offense whether you are drunk or not. Ketosis can lead to coma and death, if untreated.
Lachrymator: A lachrymator is an irritant that causes tearing (watering of the eyes). Examples include onions, tear gas, and pepper spray (capsacin). Some typical lachrymating chemicals are thionyl chloride (SOCl,) and acrolein (CH, =CH-CHO). Certain chemicals may say lachrymator on the label so treat these with respect. Use these only in a fume hood. Goggles or safety glasses are not adequate protection for lachrymators, because the fumes can still reach your eyes directly or through inhalation.
LC5,, 50% Lethal Concentration: An LC,, value is the concentration of a material in air that will kill 50% of the test subjects (animals, hopefully), when administered as a single exposure (typically 1 or 4 hours). This value gives you an idea of the relative toxicity of the material. This value applies to vapors, dusts, mists and gases, Solids and liquids use the closely related LD,, value (50%
lethal dose). The formula for determination of an LC50 is rather complex and can be found in 49 CFR 173.133(b)(l)(i). Both LC50 and LD50 values state the animal used in the test. This is important, because animal toxicity studies do not necessarily extrapolate (extend) to humans. For example, dioxin (of Love Canal, Times Beach, Sveso, and Agent Orange fame) is highly toxic to guinea pigs and ducklings at extremely low levels, but has never been conclusively linked to a
single human death even at very high levels of acute (short term) exposure.
However, it is best to err on the safe side, when evaluating animal toxicity studies and assume that most chemicals that are toxic to animals are toxic to humans. Typical units for LC50 values are parts per million (ppm) of material in air, micrograms = 0.000001 g) per liter of air and milligrams = 0.001 g) per cubic meter of air, Never be exposed to an LC50 dose of a hazardous chemical - by definition, there is a 50% chance this’will kill you.. .and if you survive you’re not going to be in good shape. Pay close attention to the permissible exposure level (PEL) instead. This is a more realistic determination of the maximum safe exposure to a material and is usually based on the known effects of the chemical on humans, rather than laboratory animals.
LD,, 50% Lethal Dose: An LD,, value is the amount of a solid or liquid material that it takes to kill 50 % of test animals in one dose. LC50 (50% lethal concentration) is a related term used for gases, dusts, vapors, mists, etc. The dose may be administered orally (by mouth), or injected into various parts of the body. The value is usually reported along with the administration method. Both LC,, and LD,, values state the animal used in the test, This is important, because animal toxicity studies do not necessarily extrapolate (extend) to humans. For example, dioxin (of Love Canal, Times Beach, Sveso, and Agent Orange fame) is highly toxic to guinea pigs and ducklings at extremely low levels, but has never been conclusively linked to a single human death even at very high levels of acute (short term) exposure. However, it is best to err on the safe side when evaluating animal toxicity studies and assume that most chemicals, that are toxic to animals, are toxic to humans. Typical units for LD,, values are milligrams or grams of material per kilogram of body weight (mg/kg or g/kg, recall that 1 kg
= 2.2 pounds). Never be exposed to an LD,, dose of a hazardous chemical- by definition, there is a 50% chance this will kill you.. .and if you survive you are not going to be in good shape. Pay close attention to the permissible exposure level (PEL) instead. This is a more realistic determination of the maximum safe exposure to a material and is usually based on the known effects of the chemical on humans, rather than laboratory animals.
Metastasis: Metastasis is the spread of a disease (usually cancer) from an original site of infection to other parts of the body. This usually happens when cancer cells break off from the original tumor and travel through the blood
vessels to a new site. This kind of cancer is called malignant, meaning that it is life-threatening and usually fatal.
Mutagen: A mutagen is a substance or agent that causes an increase in the rate of change in genes (subsections of the DNA of the body’s cells). These mutations (changes) can be passed along as the cell reproduces, sometimes leading to
HAZARDS IN THE CHEMICAL PROCESS INDUSTRIES 49
defective cells or cancer. Examples of mutagens include biological and chemical agents as well exposure to ultraviolet light or ionizing radiation. There are many types of mutations, some of which are harmful and others, which have little or no effect on the body's function. See the Life Science Dictionary at the University of Texas, for examples. Mutagens can be identified using the Ames test and other biochemical testing methods. Do not confuse a mutagen with a carcinogen (a substance that causes cancer). Mutagens may cause cancer, but not always. Do not confuse a mutagen with a teratogen (a substance that causes change or harm to a fetus or embryo). Whenever you work with a mutagen be sure to wear proper protective equipment (PPE) and minimize your exposure.
Narcosis: Narcosis is a state of deep stupor or unconsciousness, produced by a chemical substance, such as a drug or anesthesia. Inhalation of certain chemicals can lead to narcosis. For example, diethyl ether and chloroform, two common organic solvents, were among the first examples of anesthesia known. Many other chemicals that you would not suspect can also cause narcosis. For example, even though nitrogen gas comprises 80% of the air we breathe and is considered chemically inert (unreactive) it can cause narcosis under certain conditions.
Always work with adequate inhalation and avoid inhaling chemical fumes, mists, dusts etc. whenever possible. Use fume hoods and respirators as necessary.
Necrosis: Necrosis is the death of cells or tissue due to disease, injury, exposure to chemical agents, radiation etc. Necrotic tissue can be found anywhere in the body, but is generally a localized phenomenon. When extremely large areas of tissue are involved, the condition is generally called gangrene. Corrosive materials may cause painful chemicals burns and necrosis of the skin or eyes.
Always wear proper personal protection equipment (PPE) such as gloves and goggles when dealing with such materials.
Neoplasm: A neoplasm is an abnormal growth of tissue that has no useful function. A synonym is "tumor, " Neoplasms may be benign (no ability to spread to other parts of the body) or malignant (cancerous). Chronic (long-term) exposure to certain chemicals can result in the formation of neoplasms. While not all of these tumors are cancerous, benign tumors have the potential to interfere with vital body functions or become malignant. Limit your exposure to chemicals that are known to cause neoplasms (tumors). This includes reducing the usage of such chemicals in your workplace as well as using proper personal protective equipment (PPE) such as gloves, respirators and fume hoods. Related terms are carinogen, carcinoma, malignant, mutagen, and teratogen.
NIOSH
-
National Institute for Occupational Safety and Health: The National Institute for Occupational Safety and Health, NIOSH, is part of the U.S. federal government's Centers for Disease Control and Prevention (CDC). NIOSH's website is http://www .cdc.gov/niosh/homepage.html. NIOSH is the only federal Institute responsible for conducting research and making recommendations for the prevention of work-related illnesses and injuries. NIOSH was created by the Occupational Health and Safety (OHS) Act of 1970. OSHA is responsible for creating and enforcing workplace safety and health regulations while NIOSH is in the Department of Health and Human Services and is a research agency.
Examples of NIOSH activities include: investigating potentially hazardous
working conditions as requested by employers or employees; evaluating hazards in the workplace, ranging from chemicals to machinery; creating and disseminating methods for preventing disease, injury, and disability; conducting research and providing scientifically valid recommendations for protecting workers; providing education and training to individuals preparing for or actively working in the field of occupational safety and health; creating new ways to
prevent workplace hazards is the job of NIOSH. Many NIOSH-approved standards appear on MSDSs. Other examples of NIOSHs involvement with MSDSs: NIOSH cooperates with other world agencies in providing International Chemical Safety Cards which, while not strictly MSDSs, provide workers with succinct information about the hazards of chemicals; NIOSH plays a role in establishing PEL, TLV and STELs for a variety of chemicals; the NIOSH Pocket Guide to Chemical Hazards (NPG); NIOSH publishes Occupational Health
Guidelines for Chemical Hazards listed by chemical; The Registry for Toxic Effects of Chemical Substances (RTECS), a toxicology database containing over 140,000 chemicals substances.
NTP- National Toxicology Program: The National Toxicology Program (NTP) is a unit of the U.S. Department of Health and Human Services. NTP coordinates toxicology research and testing activities within the Department and provides information about potentially toxic chemicals to regulatory and research agencies and the public. NTP is the world leader in designing, conducting, and interpreting animal assays for toxicity and carcinogenicity. Their web home page is http://ntp-server.niehs.nih.gov/. The NTP consists of relevant toxicology activities of the U.S. National Institutes of Health's National Institute of Environmental Health Sciences (NIH/NIEHS), the U.S. Centers for Disease Control and Prevention's National Institute for Occupational Safety and Health (CDC/ NIOSH), and the U. S. Food and Drug Administration's National Center for Toxicological Research (FDA/NCTR). The NTP's Annual Reports on Carcinogens (see the latest edition) are one of the four sources used by OSHA to declare substances as carcinogens. NTP is one of your most trusted sources when it comes to information about toxic chemicals or potential carcinogens.
Nystagmus: Nystagmus is a rapid, involuntary, motion of the eyeball (side to side, up and down, rotating and/or oscillating). Nystagmus can be caused by
HAZARDS IN THE CHEMICAL PROCESS INDUSTRIES 51
tumors or drugs (such as barbiturates). It can also be a congenital condition (present at birth). Exposure to certain chemicals can cause nystagmus. This condition is very easy for other persons to observe. Be certain you read the MSDS's for all chemicals that you are working with and note whether exposure to any of these can cause this condition.
OSHA- Occupational Health and Safety Administration: The U.S
.
Occupational Health and Safety Administration, OSHA, is a federal government agency in the U.S. Department of Labor. OSHA's web site is http://www.osha.gov/. The primary goals of OSHA are to save lives, prevent injuries and protect the health of America's workers. OSHA employs over 2,000 inspectors to ensure job site safety. OSHA was created by the Occupational Health and Safety (OHS) Act of 1970. While many see OSHA as an intrusive government agency intent on enforcing arcane rules, the fact is that OSHA saves lives. And if that is not enough for you, their Voluntary Protection Plan (VPP) saves money by reducing the cost of injuries, accidents, downtime and litigation.
OSHA's Hazard Communication Standard 1910.1200 requires employers to establish hazard communication programs to transmit information on the hazards of chemicals to their employees by means of labels on containers, material safety data sheets, and training programs. Implementation of these hazard communication programs will ensure all employees have the "right-to-know" the hazards and identities of the chemicals they work with, and will reduce the incidence of chemically-related occupational illnesses and injuries. The OSHA HazCom standard specifies the required elements that must be on an MSDS among other important data. It is a very readable document, and it is suggested that anyone involved with MSDS management print out a hard copy for future reference. OSHA has a suggested format for MSDS's, Form 174 (OMB #1218- 0072). You can download this form in HTML or PDF format from the U.S.
Department of Labor's Occupational Safety and Health Administration world wide web site, if you wish. While this format is nonmandatory, it is a frequently utilized format. An MSDS can contain more information than that required by OSHA, but not less. Form 174 has the following sections: Chemical Identity- The identity of the substance as it appears on the label. Section I. Manufacturer's Name and Contact Information: Manufacturer's name, address, telephone number and emergency telephone number. Date the MSDS was prepared and an optional signature of the preparer
.
Section 11. Hazardous IngredientsIIdentity Information - Lists the hazardous components by chemical identity and other common names. Includes OSHA PEL (Permissible Exposure Limit), ACGIH TLV (Threshold Level Value) and other recommended exposure limits.Percentage listings of the hazardous components is optional. Section 111.
Physical/Chemical Characteristics - Boiling point, vapor pressure, vapor density,
specific gravity, melting point, evaporation rate, solubility in water, physical appearance and odor. Section IV. Fire and Explosion Hazard Data
-
Flash point (and method used to determine it), flammability limits, extinguishing media, special firefighting procedures, unusual fire and explosion hazards. Section V.Reactivity Data - Stability, conditions to avoid, incompatibility (materials to avoid), hazardous decomposition or byproducts, hazardous polymerization (and conditions to avoid). VI. Health Hazard Data - Routes of entry (inhalation, skin, ingestion), health hazards (acute = immediate and chronic = build up over time), carcinogenicity (NTP, IARC monographs, OSHA regulated), signs and symptoms of exposure, medical conditions generally aggravated by exposure, emergency, and first aid procedures.VI1. Precautions for Safe Handling and Use
-
Steps to be taken in case material is released or spilled, waste disposal method, precautions to be taken in handling or storage, and other precautions. VIII.Control Measures
-
Respiratory protection (specify type), ventilation (local,mechanical exhaust, special or other), protective gloves, eye protection, other protective clothing or equipment, worklhygienic practices. A competing format, the ANSI format is emerging as the standard format for MSDS. This format contains all of the information found on Form 174, but includes additional information/categories and has a consistent organization.
Permissible Exposure Limit (PEL): A Permissible Exposure Limit (PEL) is the maximum amount or concentration of a chemical that a worker may be exposed to under OSHA regulations. PEL can be defined in two different ways as discussed in the OSHA regulation on air contaminants 1910.1000: Ceiling values at no time should this exposure limit be exceeded. 8-hour Time Weighted Averages (TWA): This is an average value of exposure over the course of an 8 hour work shift. TWA levels are usually lower than ceiling values. Thus, a worker may be exposed to a level higher than the TWA for part of the day (but still lower than the ceiling value) as long as he is exposed to levels below the TWA for the rest of the day. See 1910.1000 for the formulas used in the calculations. PELs are defined by OSHA in 3 Tables: Table 2-1 Limits for Air Contaminants, Table 2-2 Acceptable maximum peak above the acceptable ceiling level for an 8 hour shift, Table 2-3 Mineral dusts. In general, PELs refer to substances that may be inhaled, although some can be absorbed through the skin or eyes. When working with materials that have a PEL or TWA listed use proper precautions to minimize the generation of a vapor or dust in the first place, Always use appropriate personal protective equipment (PPE) such as gloves, dust masks, and respirators to limit your exposure to chemicals, Remember, exposure limits are not some magic threshold that define the border between safe and dangerous. A PEL that was acceptable in 1950 may be recognized as dangerously high today. Therefore, always do everything reasonable to limit the
HAZARDS IN THE CHEMICAL PROCESS IMlUSTRIES 53
airborne release of chemicals or dusts in the first place. Chemical Sampling Information at OSHA lists the PELS and/or TWAs for many substances, health effects, and equipment/manufacturers that can monitor concentration for PEL/TWA compliance.
Poison: A poison is a substance that adversely affects one's health by causing injury, illness, or death. A gas poisonous by inhalation is defined by 49 CFR 173.1 15 as "material which is a gas at 20
"C
(68 OF) or less and a pressure of 101.3 kPa (14.7 psi) (a material which has a boiling point of 20"C
(68 OF) or less at 101.3 kPa (14.7 psi)) and which: (1) Is known to be so toxic to humans as to pose a hazard to health during transportation, or (2) In the absence of adequate data on human toxicity, is presumed to be toxic to humans because when tested on laboratory animals it has an LC50 value of not more than 5000 d / m 3. . .
LC50values for mixtures may be determined using the formula in Sec.
173.133(b)( l)(i) of this subpart. I' A poisonous substance (other than a gas) is defined by 49 CFR 173.132 as a material "which is known to be so toxic to humans as to afford a hazard to health during transportation, or which, in the absence of adequate data on human toxicity: Is presumed to be toxic to humans because it falls within any one of the following categories when tested on laboratory animals (whenever possible, animal test data that has been reported in the chemical literature should be used): Oral Toxicity: A liquid with an LD,, for acute oral toxicity of not more than 500 mg/kg or a solid with an LD,,for acute oral toxicity of not more than 200 mg/kg. Dermal Toxicity: A material with an LD,, for acute dermal toxicity of not more than 1000 mg/kg. Inhalation Toxicity:
A dust or mist with an LC,, for acute toxicity on inhalation of not more than 10 rng/L; or A material with a saturated vapor concentration in air at 20 "C (68 O F ) of more than one-fifth of the LCso for acute toxicity on inhalation of vapors and with an LC,, for acute toxicity on inhalation of vapors of not more than 5000 ml/m3 or Is an irritating material, with properties similar to tear gas, which causes extreme irritation, especially in confined spaces. " Treat poisonous materials with respect! Read the MSDS sheet to find out what ways a poison can kill you - is it by inhalation, ingestion and/or skin contact? What precautions should you take with the material? What kinds of personal protective equipment are recommended?
Registry of Toxic Effects of Chemical Substances
(RTECS):
The Registry of Toxic Effects of Chemical Substances (RTECS) is a toxicology database of over 140,000 chemicals compiled, maintained, and updated by the U.S. National Institute of Occupational Safety and Health (NIOSH). Its goal is to include "all known toxic substances...
and the concentrations at which...
toxicity is known to occur. RTECS was mandated by the same act that created the U.S.Occupational Health and Safety Administration (OSHA). It was originally called