Health Impact Assessment: A Tool for the Present and Future of Cities

[This article was written by Meelan Thondo, Carolyn Daher, Natalie Mueller and Mark Nieuwenhuijsen (ISGlobal) and was originally published in Catalan in Espai Salut, a bulletin published by Diputació de Barcelona]

Global urbanisation significantly affects health by bringing about social, environmental and economic changes. While cities are catalysts for economic growth, innovation and social progress, they are also epicentres of harmful environmental exposures and drivers of climate change, land-use change and natural resource depletion. The social and physical environments of cities are important assets for ensuring the health and well-being of the public.

Many developed cities face growing challenges due to non-communicable diseases such as cardiovascular disease, stroke, asthma and other respiratory diseases, cancer, diabetes and depression. As a result, although people can live long lives, many are affected by multiple chronic conditions that reduce their quality of life, daily functioning and independence. The urban poor suffer disproportionately from health risks as a result of broader political, social and economic forces that cities can address.

The COVID-19 pandemic has also underscored the critical role of cities and public space in preparing for and responding to future health emergencies

The COVID-19 pandemic has also underscored the critical role of cities and public space in preparing for and responding to future health emergencies. Through strategic urban and transport planning, actions at the city level offer opportunities for better health, a cleaner environment and climate action.

Health Impact Assessment as a Tool for Urban Health

In contexts of increasing urbanisation—as in the municipalities of Barcelona and the rest of Catalonia—tools and practices that can enable political officials to take health into account when designing urban policies have not yet been adopted as standard practice in planning processes. Nevertheless, tools such as health impact assessment (HIA) have been shown to support the integration of health into broader policy agendas focused on urban development. HIAs can contribute to the development of cities, where many policy and institutional decisions are still made without considering their health-related impacts.

Similar to environmental impact assessments, HIAs estimate the potential effects—both positive and negative—of a particular policy, programme or intervention on the health of the population. HIAs are also able to assess the distribution of these effects across the population, e.g. by socio-economic vulnerability. Studies have shown that HIAs can help stakeholders make informed decisions before, during and after the formulation and implementation of interventions or policies.

Although HIA is a fairly new approach, it is gaining traction in European countries. In Catalonia, HIAs have been conducted, for example, to estimate the impact of different noise and air pollution scenarios. Assessments can be done from either a qualitative or quantitative perspective. Quantitative HIAs based on the available data on exposure-disease relationships have been used to assess reductions in cardiovascular or respiratory diseases and deaths. They have also been used to evaluate the impacts of projects involving changes in the built environment, such as urban renewal projects.

Health Impact Assessments (HIAs) can contribute to the development of cities, where many policy and institutional decisions are still made without considering their health-related impacts

A review of the scientific literature in Catalonia identified various HIAs that analysed the health impacts of transport mode shifts in cities by comparing the health benefits of different scenarios.

• A HIA from 2012 showed that 76.15 premature deaths could be prevented each year in the city of Barcelona if 40% of car trips were replaced by a combination of cycling and public transport, thanks to reduced exposure to air pollution, reduced road traffic mortality and increased physical activity.
• More recently, a similar HIA carried out in Barcelona demonstrated the benefits of shifting to more active modes of transport, estimating that nearly 3,000 deaths could be prevented if international exposure recommendations for physical activity, air pollution, noise, heat and access to green space were met.
• Finally, a HIA from 2019 estimated that the creation of 500 “superblocks” in Barcelona could prevent nearly 700 premature deaths annually. In this case, the health improvements would be achieved by reducing air pollution, noise and heat while increasing green space and transport-related physical activity. The study also found that superblocks are a public health intervention that could be applied in other cities to reduce the health burden associated with car-centric urban planning.

Although HIA is a fairly new approach, it is gaining traction in European countries. In Catalonia, HIAs have been conducted, for example, to estimate the impact of different noise and air pollution scenarios

HIAs of other city-related health determinants, such as housing or exposure to green space, are less common. Gaps of this sort tend to be related to the lack of resources at the city level and the scarcity of data on different health exposures.

Sabadell City Council (Barcelona) / Juanma Peláez

Recommendations to Increase the Use and Implementation of HIAs in Catalonia

Now is the time to build on the momentum of health promotion in cities. In Catalonia, policies are being expanded to reflect legislation in support of HIAs as well as “Health in All Policies” approaches. To further support the implementation of HIAs in Catalonia, the following recommendations should be taken into account:

1. Increase efforts to organise and stimulate demand for knowledge and collaboration with HIA practitioners and experts from academia. HIA is a method that is more commonly used in research. Strong collaboration is needed to expand this practice into policy areas. It may be easier for Catalan municipalities to identify HIA groups at universities and research centres in order to initiate effective exchange, training and knowledge transfer.
2. Use urban data and indicators effectively. Catalonia conducts regular travel, health and household surveys that can provide the robust datasets that HIAs require. While these data may be available, accessing and managing them can still be a challenge if urban indicators are not easily understood and well planned. Using the available data effectively and focusing on relevant indicators can facilitate innovative approaches to health modelling in cities.
3. Promote greater collaboration and integration in Catalonia’s urban and transport planning sector. As certain cities begin to rack up success stories, these examples could guide various stakeholders—including the private sector, academia and public bodies—in their commitment to healthy living in cities. A health-led agenda for urban and transport planning could support a new focus on the regional aspect of urbanisation in Catalonia. Strengthening this approach could help to clarify strategies and priorities, while also highlighting the needs of the public.

The Road Ahead

The implementation of urban measures without regard for health impacts can create silos, achieve little impact on urban health and quality of life, and in some cases even exacerbate inequality. Connecting health and urban planning to policy-making arenas requires strong governance, intersectoral collaboration and equity-based practices. HIAs provide an unprecedented degree of flexibility and scientific validity to the process of estimating health risks, which can inform policy-making and contribute to a broader health agenda across all policies.

In short, HIAs can enhance the development of healthy and sustainable urban networks while also encouraging stakeholders to contribute actively to the future of their cities. Incorporating health into urban agendas can play a crucial role in improving governance and achieving healthier and brighter futures for Catalan cities.