Comparing Low Frequency Electromagnetic Fields Around NFL Football Stadiums Versus Everyday Exposure

1. Overview

Much attention in the media has been given to the presence of low frequency electromagnetic fields (LF-EMF) around the San Francisco 49ers stadium after a hypothesis gained traction that LF-EMF may be contributing to the 49ers injury woes. The 49er’s stadium is located very close to a 60kV electrical substation, which emits considerably strong LF-EMF. Our research group has connections in professional sport, with the principal investigator serving as an advisor for a Major League Baseball team as a sports medicine/sport science researcher. Further, our network includes collaborations with sport scientists from the National Football League, National Hockey League, and National Basketball Association. We plan to leverage this network to assess the impact of LF-EMF on football injury over the next six months. To maximize transparency, we are committed to sharing both our data and analysis code publicly, in addition to any published results.

2. Introduction

Prior research has indicated LF-EMF can adversely affect cellular health. ^1-6 However, in all of these cited studies, field strength ranged from 1,000-20,000 milligauss (mG). The International Commission on Non-Ionizing Radiation Protection recommends individuals not be exposed to greater than 2,000 mG at 50-60 Hz ranges found by power stations,⁷ whereas the Federal Communications Commission recommends no greater than 904 mG at 50-60 Hz ranges.⁸ Given the adverse cellular effects to higher strength fields, ^1-6 these limits make sense. However, the source of this theory is a 60 kV electrical substation approximately 100 meters from the far edge of the 49ers practice field and about 350m from the edge of the stadium (the 49ers practice fields and stadium are part of the same complex). Because LF-EMG fields weaken at an inverse square rate, this distance matters. For example, a 100 mG field 10m from a power line would be felt as (10/100)² = 0.1 mG at 100m away.

A second, confounding variable that has not received nearly as much media attention is the role other large power sources play in generating LF-EMF. Because LF-EMF weaken so quickly, large power sources inside a stadium may produce stronger LF-EMF than the power station located several hundred meters away. In theory, this would only add to the strength of the field, but in reality, may drown the background field from the electrical substation.

Because of the rate at which the strength of LF-EMF decreases, the real world strength of fields near football facilities needs to be robustly assessed before any further cellular studies are useful in determining the influence of LF-EMF on football injury. Therefore, the purpose of this proposal is to determine the strength of LF-EMF in football stadiums near and not near power stations, compare that to LF-EMF of other powered devices that humans are close to in every day activities, and predict football injuries from modeled LF-EMF strength for each NFL football team. Specifically, we propose three research questions

RQ1) What is the strength of LF-EMF of the San Francisco 49ers practice field and stadium, one control outdoor stadium, and one control indoor stadium?

H1) LF-EMF strength will be higher in stadiums than practice facilities with no difference across the three stadiums.

RQ2) How do LF-EMF levels in football stadiums compare to LF-EMF levels that humans are near for daily activities?

H2) LF-EMF levels in football stadiums will average less than close proximity to items humans live by, such as household appliances.

RQ3) What is the relationship between LF-EMF levels at each NFL stadium and practice facility and injuries of that football team?

H3) There will be no relationship between LF-EMF levels and football injuries.

The impact of this study will determine if there is merit to the hypothesis that exposure to LF-EMF is causal of football injuries. This proposal is the most foundational level and informs us if future studies are warranted. We suspect LF-EMF levels from nearby electrical substations will be insignificant compared to ambient LF-EMF and other LF-EMF emitting equipment, therefore, determining if there is a potential risk is a necessary first step before more biologic models are warranted.

3. Methods

Participants/Sample

Aim 1 of this study will include three NFL football stadiums and practice facilities. Dr. Giordano has been in contact with sport scientists for the San Francisco 49ers (reference), Seattle Seahawks (outdoor), and Atlanta Falcons (indoor), who have indicated no potential barriers in the necessary field access to perform these measurements. Aim 2 will compare values of Aim 1 to household appliances and community structures like power lines. Aim 3 will use online data to construct models based on publicly available mapping data to model LF-EMF fields from approximate power stations to each NFL stadium and practice facility. None of these require recruitment and Aim 3 will survey the entire population we hope to generalize to, rendering a power analysis useless.

Materials and Procedures

Aim 1:

This aim will map LF-EMF levels from the power station outside the San Francisco 49ers stadium all the way into the stadium and practice facility. We will measure different locations within the facility both with the stadium empty, and full with scoreboards and speakers on. We will perform the same procedure at the Seattle Seahawks and Atlanta Falcons respective facilities without the power station. To be more economical with donor dollars, Dr. Giordano has reached out to the New Orleans Saints, which would save a trip to Atlanta, as he is full time faculty at LSU Health Science Center. Materials used for this will be the ELF 3-Axis Gaussmeter, the Garmin eTrex 32x Handheld GPS, and Leico DISTO X6, to most accurately map LF-EMF values, GPS coordinate data for electromagnetic field maps, and most accurate distance to power stations and LF-EMF emitting objects.

LF-EMF levels will be measured at increments of 10m from the electrical substation toward the field, then at each corner of the football field and in the center of the field every 25 yards of the practice field. In the stadiums, LF-EMF levels will be measured outside the stadiums each cardinal direction, inside the stadium, on the concourse, in each cardinal direction, and the same playing field locations as the practice stadium. In addition, we will measure LF-EMF values next to, and at 10m increments from the scoreboard, largest subwoofers, and near the main stadium power lines, if they are accessible. Stadium measurements will be collected on both an off day and a game day (when all power is on) to determine if large electronics closer to the field produce greater LF-EMF fields than the weakening field from a nearby electrical substation.

Aim 2:

This aim will use the same ELF 3-Axis Gaussmeter as Aim 1, but will use a standard tape measure to measure distance from large household appliances and electronic devices. We will measure LF-EMF levels near a running dishwasher, running washing machine and dryer, 65” television, Wi-Fi router, telephone line, and domestic power line next to, 1m, 2m, and 5m from each device. LF-EMF values will be compared to values obtained in Aim 1 to provide reference values for the amount of LF-EMF exposure that players are receiving on the field, as we hypothesize exposure may be greater on a daily basis than 100m from an electrical substation.

Aim 3:

Aim 3 is an IF NECESSARY aim. IF LF-EMF values are higher on the 49er’s practice field or stadium than household LF-EMF levels or control stadium LF-EMF levels, THEN we will calculate the LF-EMF levels for each of the NFL’s 32 stadiums and practice stadiums based on distance to surrounding large power lines or power stations. Dr. Giordano has multiple publications performing quantitative analysis on full waveform data in the sports medicine field, allowing him to easily code models accounting for this data.^9-13 LF-EMF values for each NFL stadium and practice field will then be proportionately averaged for exposure (days on practice field vs. vs days on game field), and regressed on soft tissue injuries for each team.

Planned Analyses

The rigor of this analysis comes in proof of concept and data collection to present descriptive statistics. Data will be recorded using above stated equipment and transcribed into CSV format. All data handling, structuring and visualization will be performed in R (Version 4.4.1). If LF-EMF fields are strong higher on the 49er’s practice field or stadium than control stadiums, then we will perform Aim 3. Aim 3 will have data scraped from publicly available sources by graduate student research fellows. Calculations and analysis will be performed by Dr. Giordano, the PI of this project. LF-EMF levels will be calculated from proximity to nearest power station/power lines for each of the NFL’s 32 stadiums and practice complexes using the inverse square dissipation rate described in the introduction. Data to be scraped will be precise distances of power lines and stations relative to NFL facilities and soft tissue injuries reported by teams over the previous 5 years (for new stadiums, only available data will be used). Injury rate per athlete exposure will be calculated and regressed on LF-EMF strength in milligauss.

Ethics and Data Management

Ethical approval is not required for this project as no identifiable human data will be used. We will make data, code, and results openly available for dissemination.

5. Budget

Item	Justification	Amount
Dr. Giordano 10% FTE	For travel and time spent on this project, we estimate approximately 10% of an annual FTE will be required by Dr. Giordano to complete this project over 6 months.	$9700 salary + 38% fringe benefit = $13,386
Leica DISTO X6	Accurate distance measures from power station and electrical lines	$730 + tax and shipping = $800
Garmin eTrex 32x Handheld GPS	For mapping precise coordinates for building continuous map of LF-EMF.	$299 + tax and shipping = $350
ELF 3-axis Gaussmeter	Professional grade LF-EMF tracking equipment	$1495 + tax and shipping = $1650
Travel to San Francisco 3 nights PI + 1 student	Mapping LF-EMF on practice field and stadium with systems off and systems on	$700 flights + government rate hotels 3 x 2 x $260/n = $1560 + M&IE government rate 4 x 2 x $ 92 = $736 + ground transportation $300 = $3296
Travel to Seattle 3 nights + 1 student	Mapping LF-EMF in stadium with systems off and systems on	$800 flights + government rate hotels 3 x 2 x $220/n = $1320 + M&IE government rate 4 x 2 x $ 92 = $736 + ground transportation $300 = $3156
Travel to Atlanta 3 nights + 1 student	Mapping LF-EMF in stadium with systems off and systems on	$450 flights + government rate hotels 3 x 2 x $185/n = $1110 + M&IE government rate 4 x 2 x $ 86 = $688 + ground transportation $300 = $2548
total		$25,186
Revised total	We believe we can travel below government rates to trim $16 to the allowable amount of $25000	25,000

6. References

Ivancsits S, Diem E, Pilger A, Rudiger HW, Jahn O. Induction of DNA strand breaks by intermittent exposure to extremely low-frequency electromagnetic fields in human diploid fibroblasts. Mutat Res. 2002;519(1-2):1-13.
Simkó M, Mattsson M-O. Extremely low frequency electromagnetic fields as effectors of cellular responses in vitro: possible immune cell activation. J Cell Biochem. 2004;93(1):83-92.
Verheyen GR, Pauwels G, Verschaeve L, Schoeters G. Effects of extremely low frequency electromagnetic fields on cell proliferation and DNA integrity. Bioelectromagnetics. 2003;24(3):160-168.
Wang H, Zhang X. Magnetic fields and reactive oxygen species. Int J Mol Sci. 2017;18(10):2175.
Wolf FI, Torsello A, Tedesco B, Fasanella S, Boninsegna A, D’Ascenzo M, et al. 50-Hz extremely low frequency electromagnetic fields enhance cell proliferation and DNA damage: possible involvement of a redox mechanism. Biochim Biophys Acta. 2005;1743(2):120-129.
Zerillo L, et al. Extremely low frequency electromagnetic fields promote chondrogenic differentiation of adipose-derived mesenchymal stem cells through a conventional genetic program. Sci Rep. 2024;14:10182.
International Commission on Non-Ionizing Radiation Protection. Guidelines for limiting exposure to time-varying electric and magnetic fields (1 Hz to 100 kHz). Health Phys. 2010;99(6):818-836. doi:10.1097/HP.0b013e3181f06c86.
Federal Communications Commission. Evaluating compliance with FCC guidelines for human exposure to radiofrequency electromagnetic fields. OET Bulletin 65. Washington, DC: FCC; 1997.
Giordano KA, Wasserberger KW, Oliver GD. Altered Cervical Spine Position Results in Decreased Eccentric Shoulder Rotation Strength. Int J Sports Med. 2024 Apr 2. doi: 10.1055/a-2281-1396. PMID: 38437874.
Wasserberger KW, Giordano KA. Ground Reaction Forces in Baseball Pitching: Temporal Associations with Pitch Velocity among High Velocity Pitchers. Sports Biomechanics. November, 2023. DOI: 10.1080/14763141.2023.2284828
Giordano KA, Cassidy MM, Oliver GD. Length-Tension Differences Between Concentric and Eccentric Shoulder Rotation Strength. Journal of Strength and Conditioning Research Giordano. 2022;38(2). DOI: 10.1519.
Giordano KA, Wasserberger KW, Oliver GD. Altered Cervical Spine Position Results in Decreased Shoulder Rotation Strength. Clinical Orthopedics and Related Research. 2022. 00:1-9.
Nebel AR, Giordano KA, Schmitt AC, Oliver GD. Temporal Differences in the Kinematic Chain Between College Pitchers’ Fastest and Slowest Fastballs. Sports Medicine and Health Sciences, 2024. doi.org/10.1016/j.smhs.2024.10.001.
Giordano KA, Barrack AJ, Murrah WM, Karduna AR, Michener LA & Wasserberger KW: Usage and Acceptability of Data Normalization in Baseball Pitching, Sports Biomechanics. January 2024. DOI: 10.1080/14763141.2024.2302830
Giordano KA, Wasserberger KW. On Discretization of Continuous Data in Baseball Biomechanics and Alternative Analytical Methods. Sports Biomechanics. July 2024. DOI: 10.1080/14763141.2024.2377219

Comparing Low Frequency Electromagnetic Fields Around NFL Football Stadiums Versus Everyday Exposure

Comparing Low Frequency Electromagnetic Fields Around NFL Football Stadiums Versus Everyday Exposure

Funding Progress

Nonprofit Recipient

Topics

DOI