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LEAD PRECAUTIONS FOR AIRGUNNERS

Joe Matusic,  MD
Originally published at http://www.babymd.com/safelead.htm



This article is intended to inform airgunners of appropriate precautions to take regarding lead. There are legitimate risks to lead exposure just as there are from pointing a cocked and loaded airgun at someone. It is not my intent to scare anyone away from airguns nor do I want you to stop using your airgun. Just as you wouldn’t take apart a spring piston gun without adequate instruction and equipment, you should not ignore the risks of lead. Only with knowledge can you make appropriate decisions regarding the safe handling of lead pellets. Further, if we all approach lead with the respect it deserves, then no special interest groups can use lead poisoning in their arguments for gun control. The main risk that lead posses to you and your family is from inhalation of lead dust, ingestion of lead from lead on your finger tips from handling pellets and accidental ingestion of lead pellets.

PRECAUTIONS: THE SHORT VERSION

HEALTH EFFECTS OF LEAD: Lead can affect several areas as outlined below. The effects of lead are still not completely understood. We do know that cumulative exposure, such as through the workplace, can cause damage just as a single high dose exposure can. With chronic exposure, lead toxicity does not just abruptly show up with a symptom, rather it is a continuum of symptoms as the blood lead level increases. Some of the effects are due to permanent damage, while others are only present while the lead is present and resolve once the lead is removed.
BLOOD: Lead inhibits two enzymes necessary for blood production even at low levels. Zinc ProtoPorphyrin (ZPP) is a byproduct of lead poisoning that was first used as a screen for lead poisoning. A blood lead level of 10 ug lead / dl blood is the current limit for children. ZPP is elevated with levels as low as 20 ug lead / dl blood. As the lead level increases above 50 ug lead / dl blood, anemia is produced by two mechanisms. Acutely, poisoning leads to decreased red blood cell survival (normal adult red blood cells last 120 days and are continually produced). Chronic poisoning inhibits the body’s ability to replace the red blood cells. The symptoms of anemia include: dizziness, fatigue, weakness and increased heart rate. The normal healthy body has more than enough blood, lung and heart capacity, but those with a blood, lung or heart disorder may not have enough extra capacity to handle even minor anemia.

NEUROLOGIC: There are separate effects on the central nervous system (brain) and peripheral nervous system (nerves between the brain and muscles)

BRAIN: Ingestion or inhalation of LARGE amounts of lead, such as eating lead pellets or paint chips, can lead to rapid onset of unstoppable seizures, coma, cardiorespiratory arrest (heart and lung failure) and death. On a literature search, I did find several reports of death from lead paint chip ingestion and work related exposure, but none from lead pellet ingestion (this does not say that it cannot or has not happened). Chronic exposure can lead to irritability, restlessness, insomnia, sleep disturbances, fatigue, vertigo, headache, poor memory, muscle tremor, depression, apathy and as the level increases drowsiness, stupor, hallucinations, delirium, seizures and coma can occur. These symptoms usually do not occur below 60 ug lead /dl blood. Once these symptoms occur, they are sometimes not reversible or even recur once therapy is stopped. The treatment involves a chemical that binds the lead available in the blood and this combination is then removed from the blood. Some of the lead is deposited in the bones permanently and cannot be removed through this therapy.

NERVES TO MUSCLES: Lead seems to selectively damage the nerves leading to muscles rather than those you sense and feel with and the damage can occur at levels above 50 ug lead / dl blood. Lead also seems to affect the most used muscles more. The first effects may be seen in those muscles that extend the fingers and hand in the most commonly used extremity. This is occasionally followed by weakness in the wrist or ankle. The muscles can also develop fibrillations and fasciculations (tremors). These effects can occasionally be partially reversed with therapy.

GASTROINTESTINAL: Levels above 80 ug lead / dl blood can lead to abdominal pain, gas spasm type pain, constipation, diarrhea, anorexia, nausea, vomiting.

KIDNEY: Lead damages the ability of the kidney to filter out the toxins while retaining what the body needs. Since the kidneys have much more capacity that we normally need, the early effects of lead poisoning are difficult if not impossible to detect. Eventually, lead will result in end stage renal disease, high blood pressure, and hyperuricemia (possibly causing gout). The problem is that routine screening tests such as urine dipstick, urinalysis, and blood tests of kidney function will not show kidney disease until 2/3 of the kidney function is lost.

REPRODUCTIVE: Because of the following effects, OSHA recommends blood lead levels of less than 30 ug lead / dl blood in men and women whom wish to bear children.

MALE: Lead levels above 40 ug lead / dl blood can cause decreased sexual drive, impotence, decreased sperm production, malformed and dysfunctional sperm.

FEMALE:

MENSES (periods): Lead can cause abnormal periods, heavy blood flow or cause periods to stop happening.

FERTILITY: Lead can cause sterility, premature births, miscarriages, and stillbirths.

EGGS: Genetic and other damage con occur leading to failure to implant in the uterus, miscarriage, still birth and birth defects.

FETUS: Lead does cross the placenta as early as 12-14 weeks of gestation, but direct effects on the fetus are not well understood at this time. Certainly the neurologic effects do occur and are the most concerning. Hyperactivity can occur at blood levels of 25 ug lead / dl blood and levels of 50-60 can cause neurobehavioral impairments.

OTHER: Hypertension has been found in those whom work around lead in their job. Thyroid, blood vessel, EKG and other endocrine problems have been associated with lead poisoning, but are not well studied to date.

RISKS TO SPECIFIC AGES: All of the above are self explanatory and apply to all ages. Children are more sensitive to the neurologic effects due to their rapidly developing nervous system, while adults are more susceptible to the gastrointestinal effects. Many adults feel they are not at risk, but this is not true.

LEAD METABOLISM: When swallowed, adults absorb about 10% and children absorb about 40% of lead. Approximately 90% of inhaled lead is absorbed. Once in the blood stream, 99% of the lead is bound to red blood cells, while 1% is available to other tissues. Over time 95% of the lead is deposited in bone. Lead in the blood is excreted from the body for 6 or so months after ingestion, then the rest remains, while lead in the bone can remain for life. The average daily intake of lead through normal environmental sources is 0.2 mg and the body can handle up to 0.6 mg per day. As the amount of intake increases above this, the lead starts to accumulate. If you ingested 2.5 mg per day, it would take about 4 years to reach toxic levels. The amount of lead you can tolerate over this decreases exponentially, so that only 3.5 mg per day can cause toxicity within a few months. The average wad cutter .177 lead pellet is 7.5 grains or 487 milligrams or 812 times the amount your body can handle without starting to accumulate lead (1 gram = 15.432 grains, 1000 mg = 1 gram, 0.6 mg is upper limit for tolerance). The 0.6 mg works out to about one thousandth of the pellet. Since this is the smallest pellet, you can see how much more the other caliber pellets contain and how little it takes to cause poisoning.

NON-GUN SOURCES OF LEAD

LEADED GASOLINE: The reduction of lead in gasoline has been the most important factor in reducing by four fold the population average blood lead level over the past several decades. Leaded gasoline is still available and inhalation by adolescents trying to get high (huffing gasoline) still causes some cases of lead poisoning. Since there has been a major shift to unleaded gasoline, the percent of kids between 1-5 years with elevated blood lead levels went from 88% in 1976 to 4 % in 1991.

LEADED PAINT: This is currently the most important risk factor for children. Ingesting paint chips, while a definite source of lead poisoning, is not as common a cause of poisoning as the inhalation of lead in house dust created by deteriorating lead paint or remodeling. Lead was widely used in paint, but its use was stopped after 1978 in the USA. The older the house, the more likely you have lead based paint. For example, 85% of houses built before 1978 have lead paint, while houses built before 1950 have a higher risk of lead poisoning due to deterioration. Lead control and removal is too large a topic to cover in this article, but I will touch on it briefly below (section 6)

WORKPLACE: Certainly I would expect those whom work around lead to know that fact and take precautions as outline by OSHA rules. If you work with metal, paint removal, grinding metal or paint and you are unsure if you are working with lead, then talk with your employer or coworkers.

HOBBIES: This is an uncommonly thought of source that has caused many causes of lead poisoning. Often, since we don’t think of the hobby as a source and are not properly screened, we must wait until signs of lead poisoning show up to find these cases, but in some cases the damage is irreversible. Lead is found in certain ceramic glazes (home made pottery), stained glass (the channel holding it and the solder), lead figures, some jewelry, leaded crystal, and pewter.

OTHER: Some supplements, herbal and other home remedies (especially Chinese herbal medicine) have been found to have high lead levels and some children have actually died from lead poisoning from this source. There are isolated reports of lead being used to repair things that contain food, thus the lead has contaminated the food and lead to food poisoning. There is also lead in artist paint pigments, ashes and fumes of burned painted wood, home battery manufacture, jewelers waste, lead type and illegally distilled alcohol (they commonly use radiators, condensers and other components soldered with lead). Cheap imported window blinds and some imported toys occasionally are found to contain high amounts of lead also.

GUN RELATED SOURCES OF LEAD: This one is fairly obvious in that we use lead bullets and lead pellets. There are sources you may not be aware of such as, lead based chemicals used in the primers and lead dust being produced in indoor ranges. Workers who clean indoor ranges and work inside the range can inhale enough lead to get lead poisoning. For firearms, there are jacketed bullets and zinc bullets, but this is not a viable option for airguns.

HOW TO PROTECT YOURSELF AND YOUR FAMILY:

NON-GUN RELATED SOURCES: After reading this article, you should look for sources and take the appropriate precautions. I think most of these are self explanatory in that you should remove the source. Lead abatement is beyond the scope of this article and you should consult your doctor, local health department or local government for information on proper lead removal (abatement). If you work around lead, then you should already be aware of what you should do or you should contact OSHA for information.

FIREARM RELATED SOURCES: Shoot outside or only in indoor ranges with appropriate ventilation systems. You can inhale lead from the gunpowder smoke (actually the primer smoke) and from the lead aerosolized when it hits metal. If you work in an indoor range, then follow OSHA guidelines for cleaning (wear protective clothing, wear appropriate and fitted air filtration masks, wet the dust when removing it and cleaning out the slugs and wash hands and face before eating, drinking or touching children).Wearing a OSHA approved and properly fitted dust mask for the purpose of lead protection may give you more protection when firing frequently in an indoor range. Unless you go to the range a lot or the range does not have the required ventilation system, then masks are probably unnecessary. Those who make their own bullets, should follow OSHA guidelines regarding lead vapor (I found at least one report of a death from an untrained person not following guidelines making lead figures in his kitchen).

AIRGUN RELATED SOURCES:

CONSIDERATIONS FOR LEAD TESTING
SYMPTOMS OF LEAD TOXICITY: If you have any of these, consult your doctor as soon as is appropriate. Make sure to tell your doctor you handle lead, as most of the following symptoms are not specific to lead poisoning. Your doctor will most likely place lead poisoning at the bottom of his or her list as a likely cause of most of these symptoms unless you tell him or her of your exposure.
GENERAL: weakness, fatigue, irritability, restlessness, depression, insomnia, sleep disturbances, apathy.

NEUROLOGIC: developmental delays and hyperactivity in children(all others in adults and children), muscle tremors, weakness, wrist or foot drop, headache, vertigo, poor memory, stupor, hallucinations, delirium, seizures and coma.

GASTROINTESTINAL: metallic taste in the mouth, constipation (early), diarrhea, abdominal pain, gas spasm type pain, anorexia, nausea and vomiting.

REPRODUCTIVE: Males may have decreases sexual desire, impotence and sterility. Females may have abnormal periods, miscarriages or sterility.

HOW TO GET TESTED: Blood testing currently must be ordered by a physician or other health care provider. There are tests that just involve a simple fingerstick and those that you must have drawn from the arm (less than a teaspoon or 5ml is required). Most local labs do not perform the test, but rather send the specimen out to a reference lab. The results should be available in less than a week. If the lead level is less than 10, then your doctor may tell you it was normal and not to worry. Please ask for the number the lab reported. The testing lab may not be able to report that no lead was found due to the inherent nature of the lab equipment, but rather will report the lowest amount as <2 ug / dl. When I see a result of <2 ug / dl, I tell my patients none was detected. When the amount is between 2 and 10, I ask the patient to repeat the test in 3 to 6 months to make sure the amount does not increase. If the level is above 10, then your doctor will have a long talk with you regarding the further evaluation and treatment required (there are standard protocols to follow and these change periodically, therefore I won’t cover them indepth here). If you have the fingerstick test, then please make sure you have not handled a lead pellet recently and have washed your hands many times thoroughly before the test is performed and ask them to stick the finger you are least likely to have touched a pellet with (or ask for the regular blood test). If you are considering having a child in the near future, then your blood lead level should be 30 or less and you should discuss this with your doctor.

HOW TO TEST YOUR ENVIRONMENT:

Water: There are test kits available at local home improvement stores to test the water. The most accurate kits involve sending a water sample to a reference lab. If your plumbing was installed by a professional after 1956, then you should be safe, but the test only costs a few dollars.

Paint: There are several ways to test the paint, from sending in paint scrapings to a lab to a special meter that is placed over the paint and can actually tell if there is lead present without destroying the paint. In West Virginia, the state will test your house for free (but only if a household member is found to have lead poisoning). Check with your local government agencies to find out how to test your paint. Lead paint for household use was outlawed in the USA after 1978, but some could be around or could be imported without customs finding it.

Dust: Dust samples can be tested by reference labs. I heard about swipes that change color if they touch lead, but I do not know enough about them to comment at this time.

ABOUT THE AUTHOR: The author is a graduate of the West Virginia University School of Medicine, did a residency in Pediatrics at the Charleston Area Medical Center in Charleston WV, is Board Certified in Pediatrics, is a Fellow of the American Academy of Pediatrics (FAAP), is an Assistant Clinical Professor of Pediatrics at the West Virginia University School of Medicine, is on several hospital and insurance company committees, has been featured in a nationally circulated video on immunizations, has appeared in numerous local television broadcast regarding childhood health, has been in private practice in Charleston WV since 1992, and is designated by the Federal Aviation Administration as an Aviation Medical Examiner. The author maintains a web site at www.babymd.com. The author is an avid airgunner, enjoys wood working and paramotoring (paragliding with a motor) and to date has two children. You may reach the author via e-mail at [email protected].

REFERENCES:

Morbidity and Mortality Weekly Report (MMWR)

Occupational Safety and Health Administration (OSHA) web site

National Institute for Health (NIH) web site

Nelsons Pediatrics (latest edition)

The Pharmacological Basis of Therapeutics, 9th ed, Goodman & Gilman’s

Dr. Matusic's silent (and lead contained) airgun pellet  trap

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