Dar es Salaam is a compelling place to conduct such a study. With a population that has swelled past five million people according to Tanzania’s 2022 census, the city has experienced a rapid expansion of telecommunication infrastructure to serve an increasingly connected public. Mobile phone subscriptions across Tanzania have climbed steeply in recent years, tracked by the Tanzania Communications Regulatory Authority and the International Telecommunication Union, and every new subscriber demand translates into more base transceiver stations mounted on rooftops, lattice towers, and monopoles across dense residential neighborhoods. That visible proliferation of antennas has fueled persistent public anxiety about invisible radiation, an anxiety shared by communities worldwide but often amplified in cities where towers rise directly above homes, schools, and markets.

The research team adopted a cross-sectional design, surveying forty base transceiver stations distributed across the city. At each site, they measured electric field strength using a Narda SRM-3006, a calibrated frequency-selective radiation meter that is widely regarded as a reference instrument for this kind of environmental monitoring. Unlike broadband survey meters that simply integrate all incoming energy, a frequency-selective meter can distinguish between contributions from different frequency bands, allowing the researchers to isolate the signals attributable to mobile communication services from other ambient electromagnetic sources such as broadcast transmitters. Power density, the quantity most directly compared against exposure limits, was then computed from the field measurements using standardized propagation models, following the technical conventions laid out in the International Electrotechnical Commission’s IEC 62232 standard for determining RF field strength and power density in the vicinity of base stations.

The headline numbers are striking in their smallness. The mean electric field strength across the surveyed sites was 1.654 volts per meter, with a standard deviation of 0.457 volts per meter, and the corresponding mean power density was just 0.0073 watts per square meter. To put those figures in context, the International Commission on Non-Ionizing Radiation Protection, or ICNIRP, publishes reference levels for radiofrequency exposure that are orders of magnitude higher, typically expressed in the tens of volts per meter for the frequency bands used by mobile networks. Every single measurement recorded in the study fell substantially below the ICNIRP limits, meaning that, by the yardstick used by most international regulators and by the World Health Organization in its assessments, the residents of Dar es Salaam living near these towers are not being exposed at levels considered harmful.

The statistical analysis, performed in SPSS version 23, went beyond simple averages. The researchers ran descriptive statistics, correlation analysis, and independent t-tests to probe the structure of their data. One of the most intriguing findings was what they did not find: no significant correlation emerged between the field-measured electromagnetic field values and the regulatory data held by authorities, with a correlation coefficient of just 0.031 and a p-value of 0.788, far from any conventional threshold of statistical significance. In practical terms, the measurements taken on the ground bore almost no relationship to the compliance figures on file. The authors attribute this disconnect to methodological and temporal discrepancies, a polite but pointed observation that regulatory records and real-world conditions can drift apart when measurement campaigns are conducted at different times, with different instruments, at different locations, or under different network loading conditions.

That gap matters for more than academic tidiness. Regulatory compliance for base stations is typically assessed at commissioning, using worst-case assumptions about transmitter power and antenna configuration, and then largely assumed to hold for the life of the installation. But networks are living systems. Operators add carriers, re-antenna sites, upgrade technologies from 2G through 3G and 4G and now 5G, and adjust power levels dynamically as traffic patterns shift throughout the day. A compliance certificate issued years ago may describe a tower that no longer exists in any meaningful technical sense. The Dar es Salaam findings suggest that in rapidly growing cities, where infrastructure changes fast and oversight resources are stretched, periodic independent verification is not a bureaucratic luxury but a genuine necessity for maintaining public trust.

The study also raises a subtler point about the limits themselves. While all measured values cleared the ICNIRP thresholds comfortably, the authors note that comparison with more stringent national thresholds, adopted by some countries that apply precautionary margins well below the international standard, indicates potential long-term precautionary concerns. This is a live scientific debate rather than a settled question. The ICNIRP guidelines are designed to prevent established acute effects of radiofrequency exposure, principally tissue heating, and they incorporate large safety factors. Critics, including some researchers cited in the study’s bibliography, argue that the guidelines do not adequately account for possible long-term, non-thermal effects, pointing to animal studies such as the large rat exposure experiments conducted at the Ramazzini Institute and to contested interpretations of epidemiological evidence. The scientific mainstream, reflected in systematic reviews commissioned by the World Health Organization, has generally found the evidence for harm at levels below the limits to be inconsistent and unconvincing, but the debate remains active, and a minority of scientists continue to call for lower limits and more cautious policy.

For Tanzania specifically, the study builds on earlier national assessments, including a 2013 to 2014 survey conducted by the communications regulator, and aligns with regional work such as a survey of base stations in Uganda and measurements in South Africa’s Mpumalanga province. Across these African studies, as in comparable international surveys analyzed in the exposure literature, measured levels around base stations consistently run at small fractions of the ICNIRP reference levels. The physics helps explain why. Radiofrequency power density falls off rapidly with distance from an antenna, and the highest exposures occur directly in front of the antenna face, not at ground level where people live and work. Add to that the fact that base station antennas are typically mounted high on towers and that signals are further attenuated by buildings, vegetation, and terrain, and the modest numbers recorded in Dar es Salaam become entirely predictable.

Perhaps the most forward-looking element of the paper is its argument about where research attention should go next. The authors explicitly caution against routinely replicating measurements under comparable conditions, arguing that future studies should prioritize emerging communication technologies, network densification, and evolving urban environments, where meaningful variations in exposure are more likely to occur. This is a technically astute observation. As operators deploy 5G, they are adding small cells mounted on street furniture at heights much closer to pedestrians, and they are employing massive multiple-input multiple-output antenna arrays whose beamforming behavior changes the spatial and temporal pattern of exposure in ways that traditional survey methods were not designed to capture. Network densification, by design, lowers the power of any individual transmitter while multiplying the number of transmitters, producing exposure fields that are more uniform but harder to characterize with a handful of tower-side measurements. Recent European work assessing exposure across multiple microenvironments in ten countries illustrates the kind of granular, environment-by-environment approach the Tanzanian authors are advocating.

The Dar es Salaam study ultimately delivers a double message. To residents worried about the towers on their skyline, the data offer concrete reassurance: measured levels are far below the limits that international health authorities consider protective, and the power densities recorded are thousands of times smaller than the thresholds designed to prevent heating effects. To regulators and researchers, the message is more demanding: the mismatch between field measurements and compliance records, the looming transition to denser 5G networks, and the unresolved scientific debate over long-term low-level exposure all argue for sustained, methodologically rigorous, and independently verifiable monitoring. As African cities grow and their networks multiply, the question is no longer whether tower radiation exceeds the limits, because in Dar es Salaam it clearly does not, but whether the systems for measuring, recording, and communicating that reality can keep pace with the technology they are meant to oversee.

Subject of Research: Radiofrequency electromagnetic field exposure from telecommunication towers in Dar es Salaam, Tanzania

Article Title: Levels of electromagnetic radiation from telecommunication towers in Dar es Salaam, Tanzania: implications for public exposure and regulatory compliance

Article References: John, M. Z., & Macha, I. J. (2026). Levels of electromagnetic radiation from telecommunication towers in Dar es Salaam, Tanzania: implications for public exposure and regulatory compliance. Environmental Monitoring and Assessment, 198(11), Article 1180. https://doi.org/10.1007/s10661-026-16044-z

Image Credits: AI Generated

DOI: 10.1007/s10661-026-16044-z

Keywords: electromagnetic fields, radiofrequency exposure, telecommunication towers, ICNIRP, power density, public health, Tanzania, Dar es Salaam, 5G, network densification, regulatory compliance, environmental monitoring