Document ZnqMZ38Rk8ODq2VM3OVaQnvoV

NOTICE The suggestions contained in this Manual are based upon LIA's evaluation of what it believes to be the best and most reliable data available concerning the health hazards of occupational exposure to lead. LIA notes, however, that certain of the topics dis cussed in this Manual,particularly those relating to the issue of what constitutes '"safe" biological guidelines, are the subject of continuing research and controversy. No single biological index or en gineering technique can fully protect workers; this can be accomplished only by a complete and inte grated health program which provides for biological and environmental monitoring, as well as for routine medical surveillance. PhYCOCOO.a^ TABLE OF CONTENTS Page 1. INTRODUCTION...................................................................................... 5 1.1. PURPOSE OF THE MANUAL..................................................... 5 2. WHAT IS LEAD POISONING?........................................................... 6 2.1. WHY DOES LEAD POISONINGOCCUR? ............................. 6 2.2. SUSCEPTIBILITY............................................................................. 6 2.3. FORMS OF LEAD ......................................................................... 6 3. MEASURING LEAD CONCENTRATION ................................. 7 3.1. BIOLOGICAL MONITORING................................................... 7 3.1.1. Frequency of Blood Tests................................................. 7 3.1.2. Advantages of Biological Monitoring........................... 8 3.1.3. Urinalysis ........................................................................... 8 3.2. AIR MONITORING ....................................................................... 8 3.2.1. Experience Is Required ................................................... 8 3.2.2. Personal Air Monitors ..................................................... 9 3.2.3. Air Sampling Has Limited Value ................................. 9 3.3. IF LEAD POISONING IS DETECTED..................................... 10 3.3.1. Chelation Therapy............................................................. 10 4. ENGINEERING CONTROLS AND WORKPRACTICES................. 10 4.1. ENGINEERING CONTROLS ....................................................... 10 4.2. HYGIENE ............................................................................. !.......... 11 4.2.1. Special Clothing................................................................. 12 4.3. RESPIRATORS................................................................................. 12 4.3.1. Proper Use of Respirators............................................... 13 5. KEEPING INFORMED ........................................................................... 13 5.1. 'LEAD IS UNIQUE......................................................................... 13 5.1.1. Monitoring Does Not Control Exposure .................... 13 6. CONCLUSION............................................................................................ 14 PNYC00008176 1. INTRODUCTION With the passage of the Occupational Safety and Health Act in 1970, industrial in-plant air standards were set up for the first time on a federal level. OSHA became an official part of the National Labor Law in April, 1971. The following year, in January, the National Institute of Occupational Safety and Health (NIOSH) introduced the Target Health Hazards Pro gram, with emphasis on five materials: 1. Asbestos. 2. Lead. 3. Silica. 4. Cotton Dust. 5. Carbon Monoxide. National attention, therefore, has been focused on lead because it is one of these target materials. The lead industry, of course, has been involved in re search from an occupational point of view for many years. This experience has been extremely valuable in updating the safety requirements for handling lead and lead products. 1.1. PURPOSE OF THE MANUAL Lead is toxic; nothing can make it non-toxic. The effort must focus on preventing lead's toxicity from becoming a hazard. As manager of a plant which uses lead and lead products, you have a special responsibility to pre vent lead's toxicity from becoming a hazard in the work place by providing a safe environment. Each employee shares that responsibility because, in a complete program of industrial hygiene, everv per son in the plant has a role. This Manual elaborates on the message presented in the film, "Occupational Lead Poisoning ... It Needn't Be," and has been written for manage ment personnel. It reviews the subject of work ing with lead and lead products and can be used as a guide when explaining your program to employees. The publication outlines the joint responsibility that is shared by you and your employees and suggests how to provide a healthy environment with engineering controls. You should have a program of biological monitoring to check the health of the workers at regular intervals, and you should provide certain facilities (or adequate alternatives), such as showers, tockers, and lunch rooms along with definite work practices. The work place, however, will be safe only if the employees cooperate with you. Through an educa tion program, you should explain why, for their own health and safety, the employees should abide by the work practices and biological monitoring program. PNYC0G003177 2. WHAT IS LEAD POISONING? increased concentrations of lead in their bodie Without a measure of the amount of lead in the bod' no one is aware of this build-up until the lea concentration reaches a high enough level to caui lead poisoning symptoms. You should make certain, therefore, that vou ha\ fulfilled your responsibility of insuring a safe wor environment. At the same time, each employee mu: follow the plant guidelines. 2.2 SUSCEPTIBILITY Certain people--regardless of their race, color c sex--have biological characteristics which mak them more susceptible to lead poisoning than others It is for this reason that a potential employee shouL have a thorough medical examination, including blood sample, before being considered for employ ment. The employment of any individual for lea' work must be dependent on the advice of a physi cian with knowledge about lead toxicology. Lead is absorbed through mucous membranes of lung, stomach or intestines. Nearly every chemical is a potential poison if taken in excess. It is equally true that every chemical has its own safe level or concentration at which it can be safely handled in a work environment. Lead, a natural substance, is absorbed into the body through one of the mucous membranes--the lungs, stomach, or intestines--and then enters the blood stream. If a person absorbs an excessive amount of lead, the resulting toxicity can cause a number of serious, though non-specific effects, such as anemia, fatigue, headache, weight loss, and con stipation. Severe lead poisoning can cause serious and permanent brain damage, even death. 2.1. WHY DOES LEAD POISONING OCCUR? Since lead is a natural part of many of the foods and liquids that we eat and drink, we all take some lead into our bodies each day, and we excrete some lead daily. Those people who work in lead manufac turing plants and lead-associated industries have a greater exposure to lead than the general population. This is the reason why they are more likely to have 6 2.3. FORMS OF LEAD It is well known that different lead compound exhibit vastly different solubilities. Such materials a lead sulfide, ceramic frits, or lead bisilicate, fo example, are relatively insoluble in stomach fluids. ! a person is working in this type of environment rather than in a plant containing soluble lead com pounds, that employee will probably absorb into th body a much smaller percentage of lead. When lead is absorbed, it is circulated by th blood to some location where toxicity will occur the concentration of lead is great enough. Fumes In some plants lead must be heated, sendin invisible lead fumes into the air. The fumes enter th lungs easily and, the lead can be readily absorbe into the body. Lead Dust When working in a lead-contaminated area, lea dust can collect on clothing. If proper work hygien practices are not followed, this dust can be rrans ferred to the mouth, swallowed, and absorbed mt the body. aL?s cooo pH'I 3. MEASURING LEAD CONCENTRATION More scientific data probably have been collected about lead and lead toxicity than about any other industrial chemical or metal. It is possible, therefore, to determine accurately the levels of lead absorption and to relate specific levels to toxic effect or, more importantly, the lack of toxic effect. As a result, realistic biological guidelines have been established with respect to lead concentration in the body. 3.1. BIOLOGICAL MONITORING 3.1.1. Frequency of Blood Tests Bv conducting biological monitoring, it is possible to determine accurately the concentration of lead present in the blood. Most medical authorities regard blood-lead levels above 80 micrograms of lead per 100 grams of whole blood as unacceptable. This does not mean that lead poisoning begins at the 80 level. It does mean, however, that a person's lead concentration should not be allowed to go above 80. When the blood-lead level enters that range, the risk of developing lead poisoning increases greatly. It is not possible to establish one single blood testing schedule for all employees. Blood sampling frequency depends on the individual employee and the plant in which he is working. If a person is continually absorbing large quantities of lead, you should make sure that his lead level is tested once per month. If his absorption is sufficiently low, his blood may have to be tested less frequently. Blood samples should be collected by a qualified person (e.g. plant nurse) who is familiar with the technique to avoid contamination of the sample. Analysis of the samples should be performed by a qualified laboratorv. Table 3-1 outlines a suggested biological monitoring pro gram. New Employees A new employee who has never before been occu pationally exposed to lead should initially be tested more frequently than a long-term employee--until his work habits are determined and his biological reaction to the environment is established. (Refer to Table 3-1.) Table 3-1 SUGGESTED FREQUENCY OF BIOLOGICAL MONITORING Previous BloodLead Level_________ Frequency of BloodLevel Determination Below 40 fi%!lOOg .......... At least yearly 41-60 #tgil00g.................. Every 3 months Above 60 Mg'lOOg .......... Monthly New Employees .. .Monthly for first 4 months PNYC00008179 Action Level A lead concentration of 60 micrograms per 100 grams of rvhole blood has been recommended as the "Action Level." There is no magic in this number; it is used as a guide only in order to assure that action to control exposure is taken before the 80 level is reached. Also, blood-lead testing should become more frequent (monthly) when the blood-lead reaches'60 or higher. 3.1.2. Advantages of Biological Monitoring Biological monitoring indicates the amount of lead that has actually been absorbed into the body. This information cannot be determined as accurately bv any other method. Biological monitoring has these advantages: It is possible to detect potential hazards and a small build-up before the employee has absorbed a toxic amount of lead. Any increase in exposure to small lead particles, or to lead compounds that are soluble enough to enter the blood stream, will show up in the blood test long before an employee begins to feel the effects of lead in his system. The initial symptoms of lead poisoning are so general that they could easily be mistaken for a stomach upset, influenza, or similar conditions. A regular biological monitoring program is the only method by which lead build-up. and potential lead poisoning, can be detected. Only biological monitoring can measure total ab sorption of lead from all sources, both on and off the job. 3.1.3. Urinalysis Biological monitoring by urinalysis is useful as a screening method for determining the relative expo sure to lead. However, urinalysis is less dependable than blood-lead analysis. Urinalysis may not give a true indication of the lead concentration in the body. If an employee should drink an unusually large amount of fluid before the sampling, for example, the lead would be diluted, and the resulting urinalysis would indicate a lower lead concentration than actu ally exists. Blood sampling, on the other hand, is much less subject .to variation, as the concentration of lead in the blood is uniform throughout the circulatory sys tem. It does not vary with fluid intake. Other tests, such as urinary coproporphvrins, uri nary delta aminolevulinic acid (d-ALA), free erythro cyte protoporphyrin (FEP), zinc protoporphyrin 8 (ZPP), or delta aminolevulinic acid dehvdratase (ALA-D) in blood, have been studied for their po tential use for biological monitoring. At present, these tests are not as well documented as bloodiead levels. Although thev mav be used as screening tools, the blood-lead should serve as a final basis for action. 3.2. AIR MONITORING Air monitoring is a method of determining the concentration of lead in the plant atmosphere to which an employee is exposed. This monitoring method is a valuable tool for testing engineering controls. If the lead concentration in the atmosphere has increased since the previous air monitoring, von should check all controls and determine whv the lead increase has occurred--then correct the problem. However, air monitoring or sampling should not be used as a substitute for biological monitoring, for these reasons; 1. Air sampling is one step removed from the employee. 2. While air sampling does give an indication of the relative amount of lead present in the air. it does not indicate whether that lead is readily soluble (easilvabsorbed) or insoluble (absorbed at a low rate). 3. Under occupational exposure conditions, there is no predictable relationship between the lead concen tration in air and that in the blood stream of an employee. 4. Air sampling cannot indicate that an employee is building up a lead concentration. Such a build-up can be detected only by the biological monitoring method. 5. While the monitors may also indicate the need for personal protection devices, such as a respirator, they will not judge their effectiveness. 6. Air monitoring cannot measure total exposure, both on and off the job. 3.2.1. Experience Is Required Air monitoring must be supervised by a qualified person who is experienced in conducting an indus trial hygiene survey. It is advisable to take repeated air samples over a period of time in order to average out fluctuations in airborne concentrations of lejJ which might occur on any particular day. This long term method will make it possible to measure more accurately the air-lead levels to which worker** are actually exposed. If there seems to be an increase ;n lead concentration, you should check all engineering controls and determine the reason for the build up--rthen correct the problem as quickly as posable pNtCOOOO8100 Air mortitonng is valuable tool for testing engineering controls. 3.2.2. Personal Air Monitors These can be used to indicate how much airborne lead is present in the breathing zone of an individual employee. When conducting a test with a personal air sampler, take these precautions. 1. Become familiar with the proper operation of the sampling equipment. 2. Insure that the air pump is properly calibrated. 3. Avoid contamination of the filter. 4. Be certain that the lead analysis of the filter is carried out by a qualified laboratory. NOTE: Simple air samplers do not differentiate between large and small particle sizes. Large lead particles will not enter the lungs; small particles can enter and may be absorbed. This is one of the reasons why, under occupational exposure condi tions, there is no predictable relationship between lead concentration in the air and lead concentra tion in an employee's body. Biological monitoring must be used to determine the lead concentration in the bloodstream. 3.2.3. Air Sampling Has Limited Value Air sampling is not as reliable as measurement of lead in blood for protecting the health of the em ployee for many reasons; such as: If an employee, who has poor hvgiene habits, or work practices, works in an area in which the lead concentration is low, he may collect lead dust on his clothes. Then, by rubbing his hands on the clothes, he could transfer the lead dust to his mouth. This ingestion of lead cannot be detected by air sampling. Very small lead particles are inhaled and absorbed into the blood stream much more easily than large particles. Shape and density of particles, as well as the solubility of lead compounds, also affect the amount of lead entering the blood stream. NOTE: Personal samplers are more easily con taminated than stationary samplers. They operate at low rates, and are subject to all problems as sociated with battery-operated equipment. Even with the most sophisticated instrumentation, environmental monitoring cannot indicate the amount of lead absorbed by any employee in a work area. Air monitoring cannot distinguish between good and poor hygiene, or good and bad work habits. 9 p*XCOOOC^Sl 3.3. IF LEAD POISONING IS DETECTED It is your responsibility as plant manager to estab lish a schedule of good work practices and install reliable engineering controls. Under these circum stances. no employee should develop symptoms of lead poisoning, provided each one cooperates fully with you bv (It participating in a proper biological testing program, and (2) developing good personal habits. But if an employee does happen to develop early lead poisoning symptoms for some reason, the employer should do the following: 1. Put him under medical supervision im mediately. 2. Remove him from all lead exposure. 3.3.1. Chelation Therapy A chelating agent is any substance that chemically binds another substance. A chelating agent for lead, for example, combines with the lead in the blood, producing a chemical complex which is excreted from the body. Chelation therapy must be prescribed only by a physician. Chelation therapy should not be used as a preven tive to rid the body of lead before lead poisoning occurs. The proper way to prevent lead poisoning is to prevent absorption--not by the use of drugs. IV/iem To Use Chelation Therapy Chelation therapy is a fairlv effective treatment for lead poisoning if it is prescribed by a physician and carried out carefully under medical supervision. WARNING A person should not treat himself for lead poison ing at any time. Chelation therapy should be pre scribed only by a physician. Employees receiving this treatment should not be exposed to lead at any time during chelation therapy, and chelation must not be routinely used to maintain lowered bloodlead levels. A specific chelator for lead will also remove other metals from the body, such as zinc and copper. This could upset the biological balance in a per son's body, again indicating the need for medical supervision during therapy. 4. ENGINEERING CONTROLS AND WORK PRACTICES The plant manager and all employees have a joint responsibility for protecting all workers from lead poisoning. You, as the manager, must provide the proper working environment, along with engineer ing controls to maintain that environment. You must also provide special facilities, such as a shower room, a locker room, and a separate area for eating, or adequate alternatives. At the same time, the employees should follow a good program of personal hygiene, and they should abide by the work practices. Neither smoking nor eating should be allowed in exposed areas. Full cooperation is absolutely necessary to protect the health of each employee. If any worker does not follow these suggestions, he could develop lead poisoning. Lead can accumulate in the body. The metal can build up each day, and if an employee does not 10 follow the recommended procedures on personal hygiene, it could build up to a dangerous level, and poisoning may result. There is a long recovery period of many months. 4.1. ENGINEERING CONTROLS The plant manager must take special precautions in all hazardous areas in order to eliminate the possibility of lead poisoning. Follow these sug gestions: 1. Isolate the more hazardous operations from the general plant area. House them in a room by themselves. 2. Enclose lead-containing vessels, whenever pos sible. to prevent the escape of fumes. 3. Always remove dust at the source by means of PNVC00008I82 7. Dispose of lead-bearing waste in an environ mentally acceptable manner. 8. Don't create dust clouds by poor work practices, such as clapping together contaminated objects or clothing. When possible, sources of fume should be enclosed. local exhaust ventilation, or by enclosed dis charge and collection systems. 4. Do not let fumes circulate through the plant. Extract them at their origin by means of air cleaning systems whenever possible. 5. When transporting, mixing, or feeding leadbearing materials into vessels: Take steps to prevent spillage. Dampen any dry, powdery materials, when ever possible, to prevent them from becoming airborne. 6. NEVER DRY-SWEEP THE FLOOR. If dust, or other lead-bearing materials, collect on the floor, always try to use vacuum scrubbers to clean up, whenever plant design and house keeping permit it. 4.2. HYGIENE 1. VVhen working in a lead-contaminated area, an employee is certain to get lead dust on his hands. Caution him on these critical points: Always wash hands before eating or smoking. Eat in a lunchroom which is completely separate from lead-processing area. Never put hands in mouth. Smoking should be discouraged within the plant but, if permitted, should be only in specific "clean'' areas. Never put any object in the mouth; it may have lead dust on it. Avoid touching lips and nostrils. Avoid rubbing sleeve of work clothing against face. Avoid inhaling dust-laden plant smoke. When lead is in a finely divided state, it is easily dissolved in the body fluids and absorbed. NOTE: It is the responsibility of the plant manager to reduce the lead concentration to the extent feasible in any contaminated area. Sever dry sweep--it only stirs up lead dust: Never put hands in mouth--lead dust may be on fingers. 11 PNYC00008133 One tupe of dual locker system used to separate soiled clothing from dean clothing. 4.2.1 Special Clothing Clothing control is an essential part of lead expo sure control. Advise the employees to follow these work practices and procedures. 1. Store street clothes in a special locker. 2. Store soiled work clothes in a special locker completely separate from street clothes or pick up a clean set each day. 3. At the end of the work day. take off the work clothes and hang them in the "dirty" locker, or have them laundered each day after work. 4. Take a shower. 5. To leave the plant, go to the "clean" locker and dress in street clothes. 6. Never take contaminated clothes home--for washing or any other purpose. These clothes could spread lead dust around and contaminate the home, where wives and children may be exposed. 4.3. RESPIRATORS Respirators are not as good as engineering con trols; however, there are some plant areas in which it is difficult, or impossible, to install adequate en gineering controls. Examples: Near a blast furnace. In a spraying operation, where an operator may have to be close to the spray gun. 12 Anv operation that is performed for only a fev minutes each day. In such cases, it may be prohibi tivelv expensive to install engineering controls. IMPORTANT Although an employee would be in this area only a short time each day, it is essential to point out to him that the area has a high lead concentration He must therefore wear a respirator for his own safety, even if only for a few minutes a day. PNYCOO0O818'. 4.3.1. Proper Use of Respirators Workers should be instructed in the proper use of respirators. You should check these kev points: 1. The respirator must be worn properlv. 2. An employee should use his own respirator only; he should not lend it to anyone else. A respirator, after repeated use, develops a contour which soon fits the face exactly. If different people use the same respirator, a close fit is never possible. 3. There must be a tight seal to prevent dust, fumes, or any foreign matter from getting to the nose or mouth. 4. The inhalation valve must be free. If valve sticks, breathing becomes difficult. 5. Clean respirator filters must be used. 6. Respirators are to be stored in a dean place so that they are not contaminated. 7. Make sure respirators are maintained properlv. 5. KEEPING INFORMED It is essential to have a thorough education pro gram so that all workers will understand the reasons for the health practices observed in the plant. New employees should receive special orientation fol lowed by periodic training programs. Because lead poisoning gives no advance warning, and because there is no way of knowing when employees are building up the lead concentration in their bodies (except by biological monitoring), it is often difficult for them to understand the reasons for specific work practices on a daily basis. Employees must be reminded that some lead con centration will be in their bodies--whether that concentration is measured or not. There is only one way a lead build-up in the body can be detected, and that is by biological monitoring. It is too late to avoid the problem if an employee waits until he has developed lead poisoning symptoms. The recovery program is long, and un necessary, when the alternative is preventive action based on an orderly biological monitoring program. Normally, when working in a lead exposed area where the exposure is continuous and fairly con stant, blood lead levels should stabilize. This is because lead is being excreted at approximately the same rate as it is being taken in. If the worker is moved to a different operation where his exposure could be different, his absorption may change, and blood leads should be checked more frequently until his lead level has again stabilized. Under no circumstances are employees being used as "guinea pigs" when they agree to a biological monitoring program. It should be emphasized that the blood tests are for the health of the employees, so that the lead concentrations in their bodies can be monitored at regular intervals. Only in this way can their exposure be controlled to prevent excessive lead absorption. 5.1. LEAD IS UNIQUE With most other materials, it is not possible to employ biological monitoring as a means of measur ing absorption of a toxic material. However, because of the great amount of scientific and medical infor mation on lead--due to nearly 50 years of research to define lead's behavior in the body--it is possible to utilize biological monitoring for lead. This work has provided a unique and effective tool which should be used for the protection of the health of lead workers. 5.1.1. Monitoring Does Not Control Exposure It is important to recognize the obvious and to tell employees that biological monitoring does not con trol exposure of lead; it only reports on that exposure. As well as providing proper controls, you must encourage employees to adopt the work practices outlined in this manual. For their own safety, they should agree to a biological monitoring program. pNfC00008185 6. CONCLUSION As a plant manager, you should review the opera tion of vour plant carefullv to make sure that en gineering controls are adequate and properly main tained. Make certain that safetv precautions and work practices are followed by vour employees, as outlined m this Manual. Only in these ways can you be sure that vour employees will have a good health record, free of hazardous levels of lead in their blood. Any employer who uses or produces lead in com mercial quantities should test the blood level of each employee at least once a year, or more frequently, depending on the emplovees's individual absorption. 1. If the blood level of any employee exceeds the action level of 60 micrograms per 100 grams of whole blood, immediately determine the source of that employee's exposure to lead. 2. Check engineering controls, work practices, and personal hygiene. 3. Make sure you have a clearly understood and continuing education program. Onlv in this way will you be able to explain to vour employee the reasons for safety procedures, and the need for periodic blood tests. 4. Continually urge employees to be alert to the potential of over exposure to lead, which, ex cept through biological monitoring, provides no specific warning about the onset of poison ing. By the time a person is aware of the symptoms, a toxic amount of lead has alreadv been absorbed. 5. There is a long, difficult period of recovery from lead poisoning. The best rule tor preventing this condition is to follow the recommendations in this Manual. Remember that it is your responsibility to protect your employees. However, everyone must cooperate in order to assure a safe, healthy work place. PNYCOOOCti 1S6 14 A man can go home reasonably assured that neither he nor his family have been exposed to the hazards of lead--a hazard that need not be. PNYC00008187