Lead and Environmental Considerations
Robert D. Putnam
(This article is reprinted from the First National Shooting Range Symposium, 1990 with permission from International Association of Fish and Wildlife Agencies, Wildlife Management Institute and U.S. Fish and Wildlife Service.)
Lead is a unique and versatile element, well suited for use in ammunition. However, like many other constituents it can be toxic and as such, lead is highly regulated on the state and federal level. Regulations by the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) were designed to insure that ammunition is produced safely, but the manner in which it is used warrants special precautions.
The potential for adverse health effects resulting from excessive exposure to lead has placed sources which introduce lead into the environment under scrutiny. The Environmental Protection Agency is considering using Section 6 of the Toxic Substances Control Act (TSCA) to regulate sources of lead which they believe pose an “unreasonable risk.” Applications utilizing lead, including ammunition, will be evaluated for their potential to impact human health and the environment and the existence of possible substitutes. In the event a particular use is determined to present “unreasonable risk” to human health or the environment, and a technical and economically feasible substitute exists, lead could be banned from that application.
In addition to TSCA, there are a number of Congressional initiatives currently in circulation which would authorize lead product bans. Of the two approaches, the proposed legislation is potentially the most troublesome for those of us who support the continued use of lead ammunition for recreational shooting, namely because it does not require a showing of unreasonable risk. It is imperative that risk assessment and risk management become integral parts of the decision making process when regulating products. Every effort should be made to insure that products are judged and regulated in the context of their relative risk to human health or the environment, as well as our ability to properly manage any perceived risks. Legislation authorizing product bans without a showing of unreasonable risk should be discouraged, regardless of the product under consideration.
INDOOR FIRING RANGES
There are a number of different ways in which lead dust and fume originates at ranges. These include; primers using lead styphnate as a detonator, and the vaporization and splintering of the projectile as it passes through the weapon after being fired (NIOSH 1975). Studies by researches from the National Institute for Occupational Safety and Health (NIOSH) measured air lead levels in the breathing zones of 90 persons firing .38-caliber revolvers. Shooters firing lead bullets had mean lead exposures of 110 gglm3, calculated as an 8 hour time weighted average (TWA). 89 percent of the recorded exposures exceeded the Occupational Safety and Health Administration (OSHA) permissible exposure level (PEL) of 50 gg/m3 for occupational exposure to lead (Lee 1986). Although most indoor firing ranges are not subject to OSHA standards, lead exposures should and can be maintained below levels of concern for protection of human health.
Children, and in some instances the unborn child, are at greatest risk to high level lead exposures. If a woman of child bearing age were continually exposed to air lead levels in this range due to employment in, or active participation in recreational shooting, her blood lead level could exceed 10 – 15 gg/dl, the level of concern for the fetus. Since the blood lead level of the unborn fetus is the same as that of the mother, some would argue that an undue risk has occurred. Therefore, some form of risk management should be undertaken to reduce the risk of lead exposure to the most sensitive populations.
The simplest measure to minimize exposure is to implement administrative controls such as limiting the time a person spends in the range. Range employees such as range masters or instructors are most susceptible to higher exposures since they spend a greater amount of time in the firing area. Where possible, range workers should operate within glass enclosed work spaces with ventilation separate from that of the firing area. Employees responsible for the general housekeeping of the range and anyone involved in the reclamation of spent lead collected at the bullet trap should wear NIOSH approved respirators. Remelting of spent lead within the confines of the range should be prohibited. Additionally, biological monitoring programs that include routine physicals and periodic checks of blood lead levels should be implemented for all range employee’s. Blood lead levels should be maintained below the OSHA standard of 50 gg/dl. Levels in excess of 50 gg/dI would indicate high exposures in the range and necessitate more extensive monitoring and measures to control the exposures.
Proper ventilation systems can be sufficient to protect range employee’s and shooters, but they can be difficult to institute, especially as retrofits, and highly efficient ventilation systems are costly to bring on line and operate (NIOSH 1975). When a weapon is fired, much of the dust and fumes which result are released at right angles to the direction of fire. This “side blast” creates turbulence in the breathing zone of the shooter and poses special problems for ventilation systems since excessive turbulence could cause the lead dust and fumes to be blown back into the shooters face. Caution must be exercised in design to insure even air flow across the shooting position.
All air being exhausted from the range should be passed through a High Efficiency Particulate Filter (HEPA) or equivalent to insure that state or federal regulations for airborne lead are not violated. Accessibility to duct work and fans should become part of the overall design and intake and exhaust velocities should be monitored periodically.
Additionally, the ventilation system should be in operation at all times while the range is in use and during cleanup.
General housekeeping and maintenance of the range also plays an important role in minimizing exposures to lead. Since much of the lead dust and fume and other particulate matter ultimately settles to the ground, floors should be appropriately constructed with a smooth surface and drains to assist proper cleanup. As a further precaution, a collection trap should be installed in each drain in order to minimize any potential for insufficiently diluted contaminants being released to the environment. The floors should never be dry swept with a broom; vacuum cleaning or wet sweeping methods should be used instead. Finally, personal hygiene should be practiced by all individuals using or maintaining the firing range to minimize the potential for lead ingestion. Eating, drinking, and smoking in the range should be prohibited and toilet and washing facilities should be installed and available to everyone using the range. While these practices may appear simplistic, they have proven extremely effective in reducing lead exposure in other lead related industries.
OUTDOOR FIRING RANGES
Ventilation is not generally a problem at outdoor ranges and so concern shifts to preventing the release of spent lead ammunition into the environment. There are studies that suggest lead pellets can be readily transformed into soluble lead compounds (Jorgensen and Willems 1987), while other studies have confirmed the uptake of this soluble fraction in both plants and animals (N1a 1989). Additionally, there is the issue of lead poisoning attributable to the direct ingestion of lead shot by game birds (Carrington and Marachi 1989). While there is a great deal of controversy surrounding many of these studies, their existence has sparked public awareness to a sufficient degree to require that they be addressed.
The future of lead ammunition use at outdoor ranges rests on the facilities ability to recover or contain the spent ammunition. Recovery is possible, but it is limited to certain circumstances. In situations where rounds are fired into a “backstop” or, in the case of traditional trap and skeet facilities, where the drop patterns of the shot are predictable and isolated to a small area, the lead can be recovered. However, when ammunition is deposited in bodies of water or natural areas such as hedgerows, recovery becomes far more difficult. Sporting clay facilities present very limited possibilities for recovering the lead shot since the drop patterns and terrain vary. In any instances where it is impracticable or impossible to recover the lead, then it must be proven that the lead can be contained so as to not present any risk to human health or the environment.
Recent legal actions by environmental groups charging that shooting ranges must be considered as point sources and subject to regulations under the Clean Water Act (CWA) and the Resource Conservation and Recovery Act (RCRA) may have a dramatic impact on the design and operation of future ranges. Under the Clean Water Act,
discharges of pollutants from point sources into navigable waters of the United States is prohibited unless the discharge is in compliance with a National Pollutant Discharge Elimination System (NPDES) permit issued by the EPA or an approved state program (301(a) CWA, 33 U.S.C. ¤1311(a)). The Resource Conservation and Recovery Act prohibits unpermitted storage and disposal of hazardous waste and open dumping of solid hazardous waste (3005 RCRA, 42 U.S.C. ¤6925)(4005 RCRA, 42 U.S.C. ¤6945).
Regardless of the outcome of present or future anti-lead initiatives, it would be wise to begin selecting new range sites which would allow spent ammunition to be periodically recovered. Additionally, it would be prudent to avoid siting new ranges in areas where ammunition would be deposited in bodies of water, acid soils, or other terrain where recovery or containment of the ammunition may be impossible.
I am optimistic that lead ammunition will continue to be a viable choice for use at recreational shooting ranges, however, the continued use of lead in any application will require that proper risk management practices be employed.
Carrington, M.E. and Mirarchi, R.E. 1989. Effects of lead shot ingestion on free-ranging mourning doves. Pages 173-179. Bulletin of Environmental Contamination and Toxicology, 1989 43(2).
Jorgensen, S.S. and Willems, M. 1987. The fate of lead in soils: the transformation of lead pellets in shooting range soils. Pages 11-15. ANSIO, 1987 16(l).
Lee, S.A. 1986. Reducing airborne lead exposures in indoor firing ranges. Pages 15-18. FBI Law Enforcement Bulletin, February 1986.
Ma, W.C. 1989. Effect of soil pollution with metallic lead pellets on lead bioaccumulation and organ/body weight alterations in small mammals. Pages 617-622. Archives of Environmental Contamination and Toxicology, 1989 18(4).
National Institute for Occupational Safety and Health (NIOSH). 1975. Lead exposure and design considerations for indoor firing ranges. 31pp. NIOSH publication no. 76-130. Cincinati, Ohio