Environmental pollutants in Shooting Sport

Introduction

Environmental pollutants are reaching worrying proportions worldwide with many pollutants  propagating human disease. In shooting sport - noise and lead are the major concerns. This article aims to provide useful data related to health issues that may be related to noise and lead pollutants in shooting sport. Based on the strength of the scientific knowledge regarding the adverse health effects of noise and lead pollutants and the magnitude of their impact on health, various interventions are recommended to minimize the risks. While ISSF holds an exclusive competency to intervene in the prevention and reduction of the harmful effects of noise and lead pollutants, this capacity must be transferred to all participants in the course of every day shooting training.

I) Noise pollution 

The World Health Organization (WHO) recommends that peak Sound Pressure Levels (SPL) not exceed 140 decibels (dB) for adults and 120 dB for youth (1,2). The majority of shooting guns produce between 150- and 175-dB peak SPL in an athlete’s ears (Table 1) (1). The majority of the air rifles generate more than 120 dB peak SPL limit for youth (1,2), although none exceeded than 140 dB peak SPL limit for adults.  

What are the risks associated with noise pollution?

The recommended SPL is consistently exceeded by shooting sport athletes (as the Table below shows). As a result, shooting sport poses a risk to the hearing of its athletes (1).  In fact, high intensity impulse sounds can damage cochlear structures of ear irreversibly. Shooting sport athletes are thus at a higher risk of bilateral, high-frequency, noise-induced hearing loss (NIHL) than others that do not shoot. Research also confirms that older shooting sport athletes have greater hearing loss than younger athletes as a result of sustained noise pollution over time.  NIHL varies depending on various factors including; the use of muzzle brakes, the number of shots fired, the distance between athletes, the shooting environment, the choice of ammunition, the use of a suppressor, and hearing protection fit and use. It is also interesting to note that:

·      Because of their shorter barrel lengths, pistols rank higher than Rifle and Shotguns in peak SPL due to the closer proximity of the muzzle to the ear. 

·      There is a difference in exposure between the two ears that may translate to asymmetrical hearing loss in rifle athletes. 

·      60% of left-handed athletes have a higher incidence of  hearing loss in their right ear and 66% of right-handed athletes report a greater incidence of  hearing loss in their left ear. 

·      In youth, shooting rifles or pistols from the seated position over a tabletop or bench increases the peak SPL. 

Table 1. Mean unweighted peak sound pressure levels for guns measured at the left ear of a right-handed athlete (1).

How to minimize the risks of noise pollution?

Here are a few suggestions to minimize the risks associated with noise pollution.

            Use of hearing protection devices

The use of hearing protection is essential in shooting ranges in order to minimize these above noted risks. Unfortunately, studies show that 38% of adult athletes and 62% of youth (aged 10-17 years) fail to wear hearing protection devices while shooting (1). Using the dual hearing protection (earplug worn in combination with an earmuff) provides the greatest protection. The fit of the protector is critical and should be securely in place before shooting (1,2). Wearer comfort is usually warranted by manufacturers. It is worth noting that the consistent use of hearing protection devices by adults acts as a good model of safety behavior for young athletes (1). 

            Other suggestions

•  Experts recommend that youth utilize smaller caliber guns and that they preferably shoot from the standing position to reduce the risk for auditory damage (2). 

•  Range design considerations and acoustic barriers minimize the auditory risk in indoor shooting ranges. 

• Increased distance between athletes and minimizing the number of shots fired reduces the risk of NIHL during shooting training (1).

All shooting sport athletes and support personnel should take head of the above noted risks shooting sport poses to an athlete’s hearing and are encouraged to implement the suggested preventative measures.

II) Lead pollution

Lead , or Pb,  is used in ammunition. Shooting ranges are thus  recognized as potential sources of Pb exposure (3) with studies reporting  that there is an elevated amount of Pb contamination in the soils of shooting ranges (4) and as an occupational hazard, athletes are also at risk from these lead particles. 

How does  pollution occur?

When a shot is fired, lead particles, associated with dust and fumes generating from the lead primer and the bullet fragments are ejected at high pressures (18,000–20,000 pound per square inch (psi); 124–128 Megapascal (MPa)) from the gun barrel and released at right angles to the direction of fire close to the athlete. (Note: Pistol ammunition contains less lead in its slug (52%) compared to rifles, the lead content of which is over 80% per slug).  As a result of this release of lead bullet fragments,  athletes often inhale fine lead particles. Additionally, fine and coarse particles from both the primer and bullet fragments are exposed to the athletes’ hands, and clothing resulting in inadvertent ingestion of particles. Another pathway is that Athletes are exposed to lead accumulated in soil dust in outdoor shooting ranges and bring these particulates back to their homes and pollute their families (5). 

What are the risks of lead Pollution?

The contamination of shooting range with lead originating from shots and bullets has been receiving increased attention as a result of the adverse health effects linked to elevated amounts of Pb found at ranges (4).

Blood Lead Levels (BLLs) remain elevated for a long time after cessation of participation in shooting events, especially for participants with higher BLLs. For adult men and women there is “sufficient evidence” that BLLs <10 μg/dL can cause reproductive problems (such as low birth weight, birth defects and decreased fertility), tremor, high blood pressure, cardiovascular disease, digestive problems, neurological disorders, memory and concentration problems, muscle and joint pain and kidney dysfunction (4,5). 

These adverse health effects are more pronounced in children and women. For children with BLLs <5 μg/dL,  there is “sufficient evidence” that this can cause decreased intelligence quotient (IQ), delayed puberty, damage to the brain and nervous system, behavioral and learning problems (e.g., hyperactivity and aggressiveness), slowed growth, hearing problems, headaches and impairment of vision and motor skills.

How to minimize the risks of lead pollution?

Lead pollution prevention is imperative to maintaining athletes’ health. Prevention mechanisms include:

•  Adequate ventilation systems in indoor ranges and development of airflow systems at outdoor ranges, clothes changing after shooting, and cessation of smoking and eating at firing ranges (5).

• Athletes must wash their hands and face with room temperature water and soap immediately following their shooting training. 

• Athletes must be monitored for their blood lead level by their family physician or team physician regularly (3).

Conclusion

Sensitizing athletes of all ages to the risks involved with shooting, both to their health and their hearing, is an important starting point.  Awareness, coupled with a multidisciplinary approach by scientific experts, are the best way forward to help reduce the effects of noise and lead pollutants in shooting sport and its athletes. It is up to all members of the shooting family to work together at all levels to develop effective policies for the sustainable management and reduction of these pollutants. 

The ISSF Medical and Sustainability Committees welcome any proposals on sustainable solutions to these growing concerns.

References:

1) Meinke DK, Finan DS, Flamme GA, et al. Prevention of Noise-Induced Hearing Loss from Recreational Firearms. Semin Hear 2017; 38(04): 267-281.DOI: 10.1055/s-0037-1606323.

2) Meinke DK, Murphy WJ, Finan DS, et al. Auditory risk estimates for youth target shooting. International journal of audiology 2014 Mar 1;53(sup2):S16-25.

3) Ontario Agency for Health Protection and Promotion (Public Health Ontario). Lead exposures among recreational shooters. Toronto, ON: Queen's Printer for Ontario; 2014.

4) Sehube N, Kelebemang R, Totolo O, et al. Lead pollution of shooting range soils. South African Journal of Chemistry 2017;70:21-8.

5) Laidlaw MA, Filippelli G, Mielke H, Gulson B, Ball AS. Lead exposure at firing ranges—a review. Environmental Health 2017 Dec 1;16(1):34.