Extensive research indicates that living in proximity to service stations poses several significant health risks, primarily related to exposure to benzene and other volatile organic compounds (VOCs) released through fuel evaporation and transfer processes. Studies consistently show elevated cancer risks, particularly childhood leukaemia, for residents living within 50–100 metres of these facilities. The risk increases with proximity, station throughput volume and the absence of emission-control technologies. Respiratory conditions, including asthma exacerbation, are also associated with such exposures. Health authorities therefore recommend minimum setback distances between service stations and residential buildings, with vulnerable populations such as children and pregnant women facing heightened risks.
Benzene Emissions and Exposure Pathways
Sources and Mechanisms of Exposure
Service stations release benzene and other hazardous compounds through two primary pathways: continuous evaporative emissions during normal operations and short-term emissions during fuel delivery. According to Health Canada’s assessment, these emissions occur during fuel storage, customer vehicle refuelling and when storage tanks are filled by tanker trucks.1 Benzene—a recognised human carcinogen present in petrol—is of particular concern because of its well-documented health effects even at low concentrations.
The magnitude of emissions varies significantly with station throughput. With benzene comprising approximately 0.6 % v/v of liquid petrol in Canada, baseline, median and high-throughput service stations (processing 1.0, 4.0 and 10.6 million L year⁻¹ respectively) emit benzene at rates of 0.25, 1.0 and 2.65 mg s⁻¹ respectively.2 These emissions create zones of elevated benzene concentration around service stations that can extend well beyond the immediate forecourt.
Dispersion Patterns and Concentration Levels
Air-dispersion modelling using tools such as SCREEN3 has been employed to estimate how benzene concentrations change with distance from station boundaries.2 Models account for wind patterns, air turbulence and humidity to predict maximum exposure concentrations at various distances. Studies have found elevated pollutant levels not only immediately adjacent to pumps but also extending 50–100 metres beyond, with the exact distance depending on station activity and local meteorological conditions.3
Indoor benzene levels can also rise in homes close to service stations. Research has identified dwellings with benzene concentrations exceeding the Agency for Toxic Substances and Disease Registry’s (ATSDR) minimal-risk level of 9 ppb, particularly in houses with attached garages or those situated very near high-volume service stations.4
Cancer Risks and Epidemiological Evidence
Childhood Leukaemia Associations
Multiple epidemiological studies have established links between residence near service stations and increased risk of childhood leukaemia. A population-based case-control study in northern Italy showed that, compared with children living ≥ 1 000 metres from the nearest petrol station, those residing less than 50 metres away had more than double the risk of developing leukaemia (risk ratio = 2.2).23 The association was even stronger for acute lymphoblastic leukaemia (risk ratio = 2.9).23
Risk follows a dose–response pattern, decreasing as distance increases. When station throughput is considered, children exposed to high-volume sites show greater leukaemia risk (RR = 1.6) than unexposed children.3
Other Cancer Outcomes
Beyond childhood leukaemia, evidence suggests associations between proximity to service stations and other cancers. A study of childhood cancer more broadly found increased risk among children living in close vicinity to petrol stations.5 The carcinogenic properties of benzene and other VOCs provide biological plausibility, as these compounds are known to cause DNA damage and cellular mutations. Health Canada has concluded that inhalation exposure to benzene from service-station emissions may pose unacceptable risks to nearby residents.1
Respiratory Health Impacts
Asthma and Respiratory Symptoms
Exposure to VOCs from service stations has been linked to respiratory problems, particularly asthma exacerbation. Residents reported more severe asthma symptoms in homes where indoor benzene exceeded 9 ppb.4 Children living near busy roads and service stations experience increased respiratory symptoms, decreased lung function, more respiratory hospitalisations and worsened asthma.4
Vulnerable Populations
Children without a family history of asthma are more likely to develop it if they live close to heavy traffic and service stations.4 The elderly, individuals with pre-existing respiratory or cardiovascular conditions and pregnant women are also considered particularly vulnerable.
Factors Influencing Exposure and Risk
Distance–Risk Relationship
Risk is greatest within 50–100 metres of service stations, declining with distance.3 For example, the Italian study cited earlier recorded a risk ratio of 2.2 for homes within 50 metres.2
Station Throughput and Activity
Higher fuel volumes lead to greater emissions and higher associated health risks. Total fuel-supply volumes exceeding 1 000 litres day⁻¹ within 250 metres of residences were linked to increased leukaemia risk.3
Environmental and Building Factors
Meteorological conditions (wind speed/direction, turbulence, humidity) affect dispersion.2 Building characteristics—such as attached garages and low-ventilation designs—can elevate indoor concentrations.4
Risk Mitigation and Regulatory Approaches
Setback Distances
Implementing minimum setbacks between new residential developments and service stations is a key mitigation strategy. Frameworks have been developed to estimate appropriate distances based on acceptable cancer-risk levels, emission rates and local exposure patterns.6
Emission-Control Technologies
Stage I and Stage II vapour-recovery systems and pressure–vacuum valves on vent stacks significantly reduce benzene emissions.61 Jurisdictions with stringent emission controls may permit smaller setbacks while maintaining acceptable risk levels.
Conclusion
The scientific evidence indicates that living near service stations increases the risk of childhood leukaemia, other cancers and respiratory illnesses, particularly within 50–100 metres of high-throughput outlets. Risk is influenced by distance, station activity, weather and building design.
Protective measures—such as mandatory setback distances, advanced emission controls and consideration of station throughput—can reduce these risks. Further research should refine exposure assessment, evaluate mitigation strategies and elucidate biological mechanisms to inform public-health protections.
Citations
1 Health Canada – “Benzene Releases from Gasoline Stations: Implications for Human Health.” ↩︎↩︎↩︎
2 Malavolti M et al., 2023 – Benzene emission rates and proximity analysis (Sci Total Environ). ↩︎↩︎↩︎↩︎↩︎↩︎
3 Population-based case-control study, Northern Italy – Childhood leukaemia and petrol-station proximity (2022). ↩︎↩︎↩︎↩︎↩︎↩︎
4 Indoor benzene and respiratory outcomes near service stations (Environ Health Perspect, 2010). ↩︎↩︎↩︎↩︎↩︎
5 Childhood cancer and residential proximity to petrol stations (Environ Epidemiol, 2019). ↩︎
6 Frontiers in Environmental Health (2023) – Framework for setback distances & vapour-recovery efficiency. ↩︎↩︎