The health and well-being of a city’s residents depends on many factors. Some cities struggle more than others to provide a clean, safe, and healthy environment for their citizens. High levels of pollution, crime, poverty, and insufficient infrastructure can all contribute to making a city an unhealthy place to live.
Air Pollution
One of the biggest contributors to an unhealthy city is air pollution. Air pollution comes from many sources, including:
- Vehicle emissions from cars, trucks, buses
- Industrial facilities like power plants and factories
- Construction sites
- The burning of coal and wood
Pollutants like particulate matter, ground-level ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide, and lead cause significant health problems. They are linked to:
- Asthma attacks
- Chronic bronchitis
- Heart disease
- Lung cancer
Children, the elderly, and those with existing health conditions are most vulnerable to the effects of air pollution. But even healthy adults can experience decreased lung function, headaches, nausea, and premature death at high levels of exposure.
Cities with the Worst Air Quality
Some of the world’s largest and most populated cities struggle terribly with air pollution. According to IQAir’s 2021 World Air Quality Report, the cities with the worst PM2.5 air pollution are:
| City | Country | 2021 PM2.5 Level |
|---|---|---|
| Hotan | China | 110.2 μg/m3 |
| Ghaziabad | India | 106.6 μg/m3 |
| Delhi | India | 96.4 μg/m3 |
| Lucknow | India | 90.9 μg/m3 |
| Dhaka | Bangladesh | 77.6 μg/m3 |
The World Health Organization recommends that annual PM2.5 levels remain below 10 μg/m3. The cities at the top of this list have yearly averages around 10-20 times higher than that limit.
Lack of Green Spaces
Access to parks, gardens, and other green spaces is another key component of a healthy city. Green spaces provide:
- Opportunities for exercise and recreation
- Cleaner, fresher air
- Space for social connection
- Mental health benefits
But many urban areas lack sufficient green spaces for residents. Concrete jungles of skyscrapers, freeways, and parking lots can make cities feel crowded and stressful. They also contribute to the urban heat island effect, which raises temperatures higher than surrounding natural areas.
Cities with the Least Green Space
Some of the cities with the smallest amount of green space per capita include:
| City | % Green Space |
|---|---|
| Singapore | 8.6% |
| Mumbai | 9.2% |
| Seoul | 9.6% |
| Hong Kong | 9.9% |
| Mexico City | 9.9% |
For comparison, cities known for their lush parks and gardens like Sydney and Vancouver have 25-50% green space coverage.
Poor Sanitation Services
Clean drinking water and adequate sanitation are basic human needs. But many cities fail to provide reliable services, leading to poor public health. Issues include:
- Contaminated drinking water from old lead pipes or polluted sources
- Unreliable water access with frequent service interruptions
- Open sewers and inadequate wastewater treatment
- Uncollected trash piling up in streets and alleys
Diseases caused by poor sanitation account for nearly 10% of the global disease burden according to the WHO. Contaminated water spreads gastrointestinal diseases like cholera, typhoid, and dysentery. Exposure to sewage spreads hepatitis A, leptospirosis, and parasitic infections.
Cities with the Worst Sanitation
The non-profit Sanitation and Water for All partnership ranks countries by their “sanitation crisis” in an annual report. The cities below come from the countries facing the most dire circumstances in the latest 2022 report:
| City | Country |
|---|---|
| Port-au-Prince | Haiti |
| Kinshasa | Democratic Republic of Congo |
| Kampala | Uganda |
| Cape Town | South Africa |
| Alexandria | Egypt |
These cities struggle to construct and maintain basic sanitation infrastructure. Residents routinely face challenges like unreliable running water, shared toilets among many households, and sewage-contaminated floodwaters.
Violent Crime
Living in fear takes a toll on mental and physical well-being. But many big cities struggle with high rates of violent crimes like murder, assault, rape, and armed robbery. Several factors drive urban crime rates:
- Concentrated poverty
- Underfunded law enforcement
- Weak gun regulation
- Organized gangs
- Illegal drug trade
Women, children, minorities, and immigrants are disproportionately victimized. Besides causing direct physical harm, violent crime erodes neighborhoods, depresses property values, and prevents people from feeling safe in their own communities.
Cities with the Highest Murder Rates
According to a 2019 study published in the Journal of the American Medical Association, the cities below had the highest homicide rates per 100,000 residents:
| City | Homicide Rate |
|---|---|
| St. Louis | 64.5 |
| Baltimore | 51.1 |
| Detroit | 39.7 |
| New Orleans | 39.5 |
| Cleveland | 33.7 |
For comparison, the average homicide rate across U.S. cities is around 5 per 100,000 residents. These cities see murder rates 10-20 times higher than average.
Homelessness
The combination of unaffordable housing, poverty, mental illness, and addiction drives urban homelessness. Living on the streets or in shelters is difficult, dangerous, and isolating. Health challenges faced by the homeless include:
- Hunger
- Exposure and frostbite
- Infectious diseases
- Violence
They also struggle to access medical care, bathe regularly, store medications properly, and recover after hospital visits. This marginalized group has a much higher risk of illness and death.
Cities with the Most Homelessness
According to the most recent data, the cities below have the largest homeless populations:
| City | Homeless Population |
|---|---|
| New York City | 91,897 |
| Los Angeles | 66,436 |
| Seattle | 12,112 |
| San Diego | 8,576 |
| Washington, D.C. | 6,521 |
High costs of living and a lack of affordable housing continue to drive these numbers up each year. Meeting the health and social support needs of homeless populations remains an ongoing challenge.
Traffic Congestion
Long commutes and time stuck in traffic cause physical and mental strain. Impacts of traffic congestion include:
- Less time for exercise and family
- Higher risk of respiratory illness
- Increased stress and anxiety
- Social isolation
- Higher rates of obesity
- Higher risk of heart disease, diabetes
Expanded highway networks often fail to solve the underlying issues. Poor urban planning, weak public transportation, urban sprawl, and over-reliance on private vehicles all feed the problem.
Cities with the Worst Traffic
TomTom’s Traffic Index Report analyzes congestion in major cities worldwide. Below are cities scoring worst on their 2019 report:
| City | Congestion Level |
|---|---|
| Mumbai | 65% |
| Manila | 63% |
| Bogota | 63% |
| Lima | 58% |
| New Delhi | 58% |
In these cities, average travel times are at least 50% longer during peak vs. non-peak hours. This hints at the daily frustrations and health costs faced by residents.
Food Deserts
Some low-income urban neighborhoods lack access to affordable, nutritious food. These “food deserts” mean residents eat fewer fresh fruits and vegetables, relying more on cheap fast food and convenience store items. Health impacts include:
- Micronutrient deficiencies
- Higher rates of obesity
- Greater risk for diabetes
- Heart disease
Food deserts occur largely in impoverished areas, where retailers face low profits and residents have reduced physical and economic access to supermarkets. Urban sprawl also plays a role, stranding households without cars far from large grocers.
Cities with the Most Food Deserts
A 2015 report by the Department of Agriculture analyzed food deserts in major metropolitan areas. The cities below had the most residents living in food deserts:
| City | % in Food Deserts |
|---|---|
| Atlanta | 26.4% |
| Memphis | 24.7% |
| Chicago | 22.9% |
| Detroit | 22.5% |
| San Antonio | 21.9% |
Bringing grocers to underserved areas and improving public transit can help ease these disparities in nutrition and wellness.
Conclusion
Building healthy cities requires reducing pollution, strengthening infrastructure, preventing crime, expanding green spaces and public transit, and addressing disparities in food access and living conditions. No city is perfect, but taking steps to improve air quality, safety, sanitation, and sustainability can go far in supporting the health of urban populations. Public health should remain central to urban planning and policy decisions.