City Know-hows
This study in Tehran examined how barriers, tree height, street proximity, and fruit type affect metal content. Results showed sites taller than 10 meters exhibited the highest cadmium levels, while barriers and proximity to streets influenced lead levels. Understanding these factors is crucial for designing safe edible green infrastructure.
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Target audience
City managers, landscape architects, urban planners, public health policymakers
The problem
We know growing food in cities can be crucial for food security and urban resilience. But keeping that food safe is critical. As researchers and landscape architects, we need to understand how environmental factors impact the presence of contaminants in urban-grown fruits.
What we did and why
We investigated heavy metal risks in urban fruits by collecting 103 samples (persimmons, olives, etc.) from various Tehran locations (gardens, streets) in Fall 2022. We focused on lead and cadmium, common environmental contaminants with health risks. We analyzed factors affecting metal uptake, including distance to streets, barrier height/width, and traffic burden (using Google Maps data). Statistical analyses helped identify spatial patterns and potential health risks associated with consuming urban fruits.
Our study’s contribution
This study offers crucial insights for designing safer edible green spaces. Our findings suggest planting fruits further from busy streets, using barriers to shield them from traffic, and implementing health-focused designs in gardens and agricultural green spaces can all reduce heavy metal content in fruits.
Impacts for city policy and practice
Our pioneering research on edible green infrastructure in Iran informs future policy and practice. Our findings can guide the development of sustainable guidelines for designing safer edible green infrastructure, promoting healthier and more resilient cities.
Further information
Full research article:
[OPEN ACCESS] Designing healthy edible cities: investigating the environmental and spatial factors affecting urban fruit safety by Mohammad Reza Khalilnezhad, Mohammad Reza Taheri, Alessio Russo, Negin Nasseh, and Ahmad Taheri.
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