LEAD POISONING – It can happen to you!

 By

Jens Heider

 Staff Member, PPSC

 

The daily exposure to toxic materials in our shooting/training environment creates a sword of Damocles above our heads. 

 

You might have received a standard form from your medical department  informing you about your lead blood level test results. Hopefully notifying you that your levels are within the permissible range. However, what does it mean to have high lead blood levels?

 

This article will try to give you the information that will be useful for you as a firearms instructor and potential victim of overexposure. It will illustrate:

 

I.                    Substance Identification

II.                 Exposure

a.      Sources

b.      Examples

III.               Health Hazards

a.      Medical Screening and Monitoring

                                                              i.      Short term (acute) symptoms

                                                            ii.      Long term (chronic) symptoms

b.      Treatment

IV.               Regulation Standards

a.      Occupational Safety & Health Administration (OSHA)

b.      National Institute for Occupational Safety and Health (NIOSH)

c.      American Conference of Governmental Industrial Hygienists (ACGIH)

d.      Environmental Protection Agency (EPA)

V.                 Prevention

VI.              Conclusion

 

I.                   Substance Identification

 

Here are some chemical facts about LEAD [1] . Inorganic lead is defined as lead oxides, metallic lead, and lead salts. The molecular formula is Pb (Latin-Plumbum). The chemical and physical properties are:

 

a.      Color: bluish-white, silvery, gray metal.

b.      Odor: odorless

c.      Molecular weight: 207.19

d.      Boiling point (at 760 mmHg): 3,164 F

e.      Melting point: 621.5 F

f.        It is insoluble in water 

g.      Properties: very soft & malleable, easily melted, cast, rolled, extruded.

h.      Use: ammunition production, material for tank linings, piping, solder, cable covering, production of other metal products, building construction, storage batteries, metallurgy, plastics, ceramics and electronic devices, gasoline additives, paint, etc.

i.        Lead consumption in the USA by product: ammunition 4.0 % of a total of 1.2 million metric tons in 1984.

 

II.                Exposure

a.      Sources

                                                               i.      The most common way in which lead enters your body is either through inhalation or indigestion. All of the lead that is stored in the body and not naturally removed, is stored in the bones and teeth. Lead is generally not absorbed through the skin.

1.      Airborne lead particles are usually created by:

a.       Combustion of either Lead Azide or Lead Styphnate in primers

b.      Exposure of the projectile base to hot gases

c.       Friction of the projectile and the barrel itself

d.      Impact against the bullet/target impact area.

2.      Lead residues can also be indigested if they get into your mouth and being swallowed. Common sources for ingestion are:

a.       Food

b.      Beverages

c.       Chewing or smoking tobacco

d.       Lipstick/make-up

e.       Lip treatments

f.        Facial hair

g.       Polluted hands/fingernails

b.      Examples

                                                               i.      54 trainees and 31 firearm instructors were evaluated at two indoor firing ranges in Amman, Jordan[2]. In the trainees, levels of BLL rose from a pre-training mean of 2.2 to 22.9 μg/dl.

                                                             ii.      81 employees of New York metropolitan police agencies[3] were tested. More than half (52 %) had blood levels exceeding 40 μg/dl, while 14 % had blood levels between 50 and 59 μg/dl at the second examination, which took place after the winter indoor season; in three cases (5 %), the blood level exceeded 60 μg/dl. The highest recorded level was 87 μg/dl.

                                                            iii.      Research[4] at an indoor range operated by the Colorado Department of Public Safety. The research shows the following lead air concentrations:

1.      Lead bullets, dilution ventilation, 2453 μg/m3

2.      Lead bullets, local exhaust ventilation, 1233 μg/m3   

3.      Copper-jacketed bullets, dilution ventilation, 205 μg/m3  

                                                           iv.      Testing was done at a covered, outdoor police range located in Richmond, VA[5]. When shooters fired conventional, non-jacketed, lead bullets, the mean exposure to airborne lead were 128 μg/m3 in personal breathing zone air samples and 68 μg/m3 in the general area air samples. The mean exposure for totally copper-jacketed bullets were 9.53 μg/m3  in  the general area air samples and 5.88 μg/m3 in personal breathing zone air samples. The airborne lead levels were reduced by a factor of 21 in the personal and by a factor of 7.5 in the general area air samples.

 

 

III.             Health Hazards

a.      Medical Screening and Monitoring[6]

                                                               i.      Anyone with potential exposures to lead should be monitored in a medical surveillance program. This should include the education, early detection, possible temporary transfer to a safe environment, and treatment if necessary. In order to evaluate any changes the physician should evaluate the medical history including tests concentrating on:

1.      Function and integrity of kidneys

2.      Measure blood pressure

3.      Focus on the gums (“lead line”) and

4.      Hematologic (blood cell forming)

5.      Nervous

6.      Gastrointestinal (stomach and intestines)

7.      Reproductive system

8.      Blood testing[7] including:

a.       Blood lead level (BLL)

b.      Zinc protoporphyrin (ZPP)

c.       Erythrocyte protoporphyrin (EP)

d.      Hemoglobin

e.       Serum creatinine

f.        Urinanalysis

9.      For blood testing the following guidelines[8] should be used:

a.       Every 6 months if < 40 μg/dl.

b.      Every 2 months if > 40 μg/dl.

c.       Monthly during medical removal from exposure.

Both BLL, EP, and ZPP are most commonly used as a diagnostic tool. The blood level  gives a relative direct measure of recent exposure. The zinc protoporphyrin enzyme (ZPP; same for EP) level provides a more indirect measurement starting to increase if the BLL is greater than 30-40 μg/dl and usually lags it 3 to 8 weeks. A normal ZPP/EP and increased BLL is a sign of recent exposure. A more reliable indicator of the total burden of lead is an x-ray fluorescence (XRF) of the bones. 

                                                             ii.      Short term (acute) overexposure symptoms

1.      Due to the toxic nature of lead, any overexposure leads to poisoning. High doses of lead can cause acute encephalopathy, a brain dysfunction, which leads to seizures, coma, and death from cardiorespiratory arrest. Cases [9] have been reported where a firearms instructor died after two weeks of  daily exposure on the range.

                                                            iii.      Long term (chronic) overexposure symptoms

1.      Chronic exposure may lead to the damage of your blood-forming, nervous, stomach & intestine, and reproductive system. Common symptoms include[10]:

a.       Loss of appetite

b.      Metallic taste in the mouth

c.       Anxiety

d.      Constipation

e.       Nausea

f.        Pallor

g.       Excessive tiredness

h.       Weakness

i.         Insomnia

j.        Headache

k.      Nervous irritability

l.         Muzzle or joint pain or soreness

m.     Fine tremors

n.       Numbness

o.      Dizziness

p.      Hyperactivity

q.      Colic

r.        Encephalopathy

 

These symptoms represent mild, moderate and severe toxic signs of exposure. Studies show that lead has a cardiovascular effect and there seem to be positive association between increased blood levels and blood pressure. The International Agency for Research on Cancer (IARC) as well as the EPA has determined to classify lead and some compounds as possibly carcinogenic to humans.

 

b.      Treatment

                                                               i.      The first step should be the removal from the exposure.

Chelation therapy[11] is being used for anyone showing severe symptoms, which is usually associated with BLL’s above 100 μg/dl. The therapy works by reducing lead in blood and soft tissues. Since the treatment is somewhat controversial it should only be done in consultation with an experienced physician.

           

IV.              Regulation Standards and Toxicity

a.      OHSA Regulations (Standards – 29 CFR) / Substance data sheet  for occupational exposure to lead, #1910.1025 App A.

                                                               i.      Permissible exposure: the Permissible Exposure Limit (PEL) set by the standard is 50 micrograms of lead per cubic meter of air (50 μg/m3), averaged over an 8-hour workday.

                                                             ii.      Health protection standard for lead blood (PbB) levels: levels are maintained at or below 40 micrograms per one hundred grams of whole blood (40 μg/100g). Blood levels of workers (both male and female) who intend to have children should be maintained below 30 μg/100g to minimize health effects. The units of milligrams (mg) or micrograms (μg) as well as 100 milliters (100 ml) or 1 deciliter (dl) or 100 gramm (100g) of a fluid are essentially the same. 

 

b.      NIOSH

Recommended exposure: the Recommended Exposure Limit (REL) is 100 microgram of lead per cubic meter of air (100 μg/m3), averaged over a 10-hour workday.

Health protection standard for lead blood (PbB) levels: levels be maintained at or below 60 micrograms per one hundred grams of whole blood (60 μg/100g).

c.      ACGIH

                                                               i.      Threshold value: the Threshold Limit Value (TLVÒ)  is at 150 micrograms of lead per cubic meter of air (150 μg/m3).

                                                             ii.      Blood lead levels: n/a.

d.      EPA

                                                               i.      Recommended exposure for the public: does not allow a higher amount than 1.5  micrograms of lead per cubic meter of air (1.5 μg/m3) for over than 3 month.

 

V.                 Prevention

a.      Control of excessive emissions of lead through adequate environmental controls and ventilation for indoor ranges.

b.      Use of  lead-free primers.

c.      Use of completely encased bullets.

d.      Use of personal protective equipment and clothing if applicable, e.g. respirators, protective coveralls, arm/sleeve protectors, shoe covers, shoe wipe-off mats, disposable gloves.

e.      Proper personal hygiene during and after firing, which should include:

                                                               i.      Washing hands, forearms and face with soap once leaving the range

                                                             ii.      Washing the hair before going to bed

                                                            iii.      Refrain from eating, drinking, smoking in range environments

f.        Proper range cleaning/maintenance procedures:

                                                               i.      Use of approved dry/wet industrial vacuums, including

1.      High Efficiency Particulate Air (HEPA) filters

2.      Explosive protected system

                                                             ii.      Wet mopping or hydro-wash

                                                            iii.      Full protective equipment.

                                                           iv.      No dry sweeping or brushing.

g.      If you have to pick up brass:

                                                               i.      Use rubber squeegees or similar tools to move brass to avoid dust development.

                                                             ii.      Do not use personal clothing, e.g. hat as storage containers for empty cases.

                                                            iii.      Hand pick if necessary.

h.      Keep personal range clothes and shoes separated and/or wash after every use.

i.        Have your blood levels checked regularly according to guidelines.

 

VI.              Conclusion

Lead exposure cannot be prevented, but it can be minimized. Use common sense like washing your hands before eating or not having open beverages on the firing range to reduce risks. A greater part is dependent on well designed indoor range systems including ventilation choices, the design of the impact area, selection of floor materials, etc. The proper choice of any so-called “Clean Range Ammunition” can help to reduce lead contamination tremendously. Even the exclusive use of frangible ammunition helps some police departments to avoid lead contamination. Whatever you have to do to reduce your personal risks and the overexposure of your students will help to create a safe training environment. Did I mention liability? It is your job to educate your department and to establish guidelines and policies that meet federal and state standards. Protect yourself, your students, and your department by establishing a Lead Awareness Program (LAP). The ball is in your lap …

 


[1] Handbook of Chemistry and Physics, 78th edition, CRC.

[2] Lead Exposure in indoor firing ranges: environmental impact and health risk to the range users; Abudhaise BA, Int J Occup Med Environ Health 1996:9(4):323-9.

[3] Exposure to Lead in Firing Ranges; Alf Fischbein, MD; Carol Rice, MS; JAMA, March 16, 1979 – Vol. 241, No. 11.

[4] Controlling Airborne Lead in Indoor Firing Ranges;Sarah K. Robbins, Kenneth D. Blehm, Roy M. Buchan; APPL OCCUP ENVIRON HYG 5(7), July 1990.

[5] Reducing Exposures to Airborne Lead in a Covered, Outdoor Firing Range by Using Totally Copper-Jacketed Bullets; R.K. Tripathi, P.C. Sherertz; Am. Ind. Hyg. Assoc. J. (51), January 1990.

[6] Occupational Safety and Health  (OSAH) Guideline for Inorganic Lead.

[7] Lewis, R.L 1997.”Metals”. In J. LaDou, Ocupational and Environmental Medicine, 2nd ed., Stamford, CT, Appleton and Lange.

[8] See 7.

[9] Risks of Lead Poisoning in Firearms Instructors and their Students by Anthony M. Gregory, ASLET Journal March/April 1990 Vol. 4, Issue 2

[10] OHSA Regulations (Standards – 29 CFR), Substance Data Sheet for Occupational Exposure to Lead, #1910.1025 App A.

[11] Occupational Lead Poisoning Prevention Program (OLPPP) Hazard Evaluation System & Information Service (HESIS) Occupational Health Branch, California Department of Health Services, September 1997.