Vulnerability of Urban Populations to Ambient Air Pollution

~Written by Joann Varickanickal (Contact: joann.varickanickal@gmail.com)

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Dannenberg et al. 2011

Urban populations have always been exposed to ambient (outdoor) air pollution because urban regions have high-density industries and populations (Dannenberg et al., 2011). High levels of pollution result from the concentration of sources of combustion (Dannenberg et al., 2011). There are two types of pollutants: primary and secondary. Primary pollutants are those that are directly emitted (Dannenberg et al., 2011). These include sulfur dioxide, which is released from power plants, and carbon monoxide from fossil fuel combustion (Dannenberg et al., 2011). In contrast, secondary pollutants result from the physical and secondary conversion of other pollutants (Dannenberg et al., 2011). Tropospheric ozone is one example; it forms through the chemical reactions of anthropogenic and biogenic precursors (Dannenberg et al., 2011).

Both primary and secondary pollutants lead to negative health consequences, including eye irritation, fatigue, headaches and more severe effects such as bronchoconstriction, lung impairment and neurological damage (Dannenberg et al., 2011). Certain populations are particularly vulnerable to ambient air pollution. For example, as a result of physiological and psychological factors, children are more sensitive to ambient pollution (Vanos, 2015). Furthermore, those with less education and lower socio-economic status also face a greater risk of exposure to ambient air pollution; thus, highlighting pollution an issue of environmental justice as well (Dannenberg et al., 2011).

Since air pollution is multifaceted, it is not easy to determine a solution. More research is required, to determine the severity of ambient air pollutants in different regions and how different populations are impacted. Furthermore, it is important to develop and implement policies that will reduce the prevalence of ambient air pollutants and their health consequences. For example, in order to provide evidence-based advice on the impacts of air pollution on health, the WHO Regional Office for Europe developed two projects-the “Review of Evidence on Health Aspects of Air Pollution” (REVIHAAP) and the “Health Risks of Air Pollution in Europe” (HRAPIE), which were completed in 2013 (WHO, 2013). The findings from these projects guided changes in the EU air quality policies that were implemented that same year (WHO, 2013).

The built environment also plays an important role in mitigating air pollution. Regions should employ sustainable development practices to ensure energy-efficient land use and transportation systems to reduce emissions (Dora et al., 2015). Moreover, attention should be given to the proximity of homes and schools to sources of pollution (Dannenberg et al., 2011). Urban Structure Types (USTs) is one method that could be used, as it is a spatial indicator that describes urban regions through the assessment of land use, physical properties and environmental characteristics (Réquia Júnior et al., 2015). The UST method assesses the morphology of housing, green spaces and industrial buildings which can be compared, to assess the relationship with a health risk (Réquia Júnior et al., 2015).

Like other global health problems, air pollution is complex. It is not unique to one region because it reaches across borders. As a result, governments and organizations from various regions need to work together to mitigate this problem.

References:

Dannenberg, A. L., Frumkin, H., & Jackson, R. J. (2011). Making Healthy Places:

Designing and Building for Health, Well-Being, and Sustainability. Washington: Island Press.

Dora, C., Haines, A., Balbus, J., Fletcher, E., Adair-rohani, H., Alabaster, G., … Neira, M. (2015). Indicators linking health and sustainability in the post-2015. The Lancet, 385(9965), 380–391. doi:10.1016/S0140-6736(14)60605-X

Réquia Júnior, W. J., Roig, H. L., & Koutrakis, P. (2015). A novel land use approach for assessment of human health: The relationship between urban structure types and cardiorespiratory disease risk. Environment International, 85, 334–342. doi:10.1016/j.envint.2015.09.026

Vanos, J. K. (2015). Children’s health and vulnerability in outdoor microclimates: A comprehensive review. Environment International, 76, 1–15. doi:10.1016/j.envint.2014.11.016

World Health Organization. (2013). Health risks of air pollution in Europe-HRAPIE project

Climate Change and Health, Part 1: Floods

~Written by Joann Varickanickal (Contact: joann.varickanickal@gmail.com)

The Lancet recently published an article on climate change and health, extensively examining the types of health risks related to climate change as well as recommendations for policy changes, in order to address these risks (Watts et al., 2015). This article re-emphasized how complex this issue is because there are several contributing factors, and elements that can be potentially impacted (Figure 1).  As there are so many aspects of this topic, for my next few blog posts I will focus on briefly highlighting some of the health risks associated with climate change. This post will focus on natural disasters, specifically looking at floods.

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Figure 1: Relationship between health, climate change and greenhouse gas emission (Watts et al., 2015)

Since 1900, floods have left more than 88 million people homeless, $595 billion in damages, and the deaths of nearly 7 million people (Khedun & Singh, 2013). Overall, climate change will have a direct impact on human health through natural disasters, such as flooding. South Asia is especially at risk as there is already regular flooding. A change in climate can affect the onset of monsoons. For example, in Kerala, a state in southern India, the monsoon season generally begins on June 1st and ends in early September, with a standard deviation of about seven days (Mirza, 2011). However, in the last 50 years this has more than doubled with the earliest onset on May 14th, and the latest date of onset on June 18th (Mirza, 2011). While this may not seem significant, it can influence the level of preparedness in communities that are at risk. Furthermore, the frequency and intensity of rainfalls will also increase. According to climate models, monsoon intensity increases during the summer, as the air over land is warmer than air over the oceans (Mirza, 2011). Floods, that result from the monsoon weather, not only increase the risk of drowning, but also affect the quality of water, thus increasing the exposure to waterborne diseases such as dysentery and diarrhea (Mirza, 2011).

Mental health issues, such as anxiety and depression, can also develop after losing property or facing a financial crisis after a flood (Khedun & Singh, 2013). Furthermore, the impacts of climate change, such as increased flooding, disproportionately influence certain populations such as marginalized communities, women, children, and the elderly (Watts et al., 2015). Thus, they suffer most of the negative health consequences associated with flooding and other disasters related to climate change (Watts et al., 2015). This highlights the complexity of the issue in terms of trying to address how to help those who are most impacted by floods.

There are several mitigation efforts that can be taken in order to reduce the impact of floods. For example, urban planners and engineers can work to ensure that forested areas are preserved and development occurs in areas where soil and vegetation conditions work best to reduce the risk of flooding. Many non-structural methods can also be implemented. For example, in some areas it may be beneficial to create zoning laws that would prohibit development in areas that are prone to flooding (Watts et al., 2015). Government officials and private officials can also work together to improve early warning systems and develop better policies for flood-insurance and emergency preparedness (Watts et al., 2015). Taking these steps can help to ensure that health issues associated with floods will not be exacerbated.

References:

Khedun, C. P., & Singh, V. P. (2013). Climate Change, Water, and Health: A Review of Regional Challenges. Water Quality, Exposure and Health, 6(1-2), 7–17. doi:10.1007/s12403-013-0107-1

Mirza, M. M. Q. (2011). Climate change, flooding in South Asia and implications. Regional Environmental Change, 11(SUPPL. 1), 95–107. doi:10.1007/s10113-010-0184-7

Watts, N., Adger, W. N., Agnolucci, P., Blackstock, J., Byass, P., Cai, W., … Costello, A. (2015). Health and climate change: policy responses to protect public health. The Lancet, 6736(15). doi:10.1016/S0140-6736(15)60854-6

Implementing Sustainable Wastewater Treatment Methods to Reduce the Risk of Waterborne Diseases

~Written by Joann Varickanickal (Contact: joann.varickanickal@gmail.com; Twitter: @joann_s_v)

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Bello Wastewater Treatment Plant, Medellin, Colombia (Photo Credit: www.water-technology.net)

The discharge of household and industrial waste can lead to the spread of waterborne diseases if left untreated because of cross contamination with drinking water or other forms of direct contact (Daley et al., 2015). This issue of wastewater sanitation has become prevalent in several low-resource countries, as the treatment of wastewater can often be expensive, and the policies needed to implement low-cost methods do not exist. 

One example of this is in Kenya, where sustainable water management practices have yet to be implemented. Furthermore, rapid urbanization and population growth have contributed to this problem (Mburu et al., 2013). Overall, due to the low operational capacities, only 5 percent of the country’s sewage is properly treated (Mburu et al., 2013). Thus, untreated or partially treated domestic wastewater is discharged into local freshwater rivers and lakes, leading to severe contamination. This not only results in the prevalence of diseases such as cholera, but it can also lead to high economic costs due to a decrease in work productivity as well as strains on the healthcare system (Mburu et al., 2013).  

Colombia has also faced issues due to ineffective wastewater treatment. While this country has not had issues of water quantity, the issue of water quality remains a problem. In some areas, nutrients, suspended solids and organic matter can be effectively removed using existing methods; however, in some areas, treatment can be difficult due to geographic location and/or cost (García, Paredes, & Cubillos, 2013). Nevertheless, many of the current systems are unable to successfully remove pathogens, which can eventually lead to waterborne diseases (García et al., 2013). 

When examining wastewater treatment in any region, in this case low-resource countries such as Kenya and Colombia, sustainable methods must be implemented. Constructed wetlands (CWs) are a possible method that can be used to improve wastewater sanitation. Characterized according to the water flow direction in the system, CWs have been implemented in various regions over the years to treat polluted water (García et al., 2013). These planted and unplanted systems have proven to remove heavy metals, nutrients and pathogens. For example, horizontal subsurface flow constructed wetlands (HSSF-CWs) have been successfully implemented for over four decades in developed countries with temperate-climates. The use of CWs has proven to be inexpensive, as it has minimal energy requirements and low maintenance needs (García et al., 2013). Thus, implementing these systems could greatly benefit many regions, and especially those that are currently facing health risks associated with wastewater treatment. 

This issue, like many others related to public health, is complex. Policy-makers, engineers, and health professionals are among the many groups that need to work together to ensure that such systems can be effectively implemented and monitored in order to reduce the health risks that are associated with contaminated water. 

References:

1.      Daley, K., Castleden, H., Jamieson, R., Furgal, C., & Ell, L. (2015). Water systems, sanitation, and public health risks in remote communities: Inuit resident perspectives from the Canadian Arctic. Social Science & Medicine, 135, 124–132. doi:10.1016/j.socscimed.2015.04.017

2.      García, J. a., Paredes, D., & Cubillos, J. a. (2013). Effect of plants and the combination of wetland treatment type systems on pathogen removal in tropical climate conditions. Ecological Engineering, 58, 57–62. doi:10.1016/j.ecoleng.2013.06.010

3.      Mburu, N., Tebitendwa, M., S., Rousseau, P.L., D., Bruggen, J. J. A. Van, & Lens, N.L., P. (2013). Performance Evaluation of Horizontal Subsurface Flow-Constructed Wetlands for the Treatment of Domestic Wastewater in the Tropics. Journal of Environmental Engineering, 139(March), 1152–1161. doi:10.1061/(ASCE)EE.1943-7870

Examining How Women are Influenced by Inaccessibility to Clean Water

~ Written by Joann Varickanickal (Contact: joann.varickanickal@gmail.com)

Since 1990, 2-3 billion people have gained access to improved drinking water sources, however, much is yet to be done, as billions still do not have access to safe drinking water (Dora, et al., 2015). This has led to several negative health consequences among many communities, as one-third of deaths are linked to the intake of contaminated water in low-resourced countries (West & Hirsch, 2013). Women are often responsible for housework such as cooking, cleaning and maintaining good hygiene. They are also mainly responsible for the care of children and the sick. As all of these tasks require the use of water, women in low-resourced countries are disproportionately affected by the inaccessibility to safe water.

Risks Associated with Water Collection

In 71 percent of households in sub-Saharan Africa women are responsible for collecting water (West & Hirsch, 2013).  As a result, in places such as the mountainous areas of Eastern Africa, women use up to 27 percent of their caloric intake to get water (West & Hirsch, 2013). Sometimes, they must travel a long distance, often several times in one day. This can lead to physical strain, especially among the elderly. This strain can be exacerbated by extreme heat or with heavy pumps at well sites. Water collection can also be dangerous in remote locations where there is increased risk of rape or other forms of violence.

Impacts on Women as Caretakers, and the Terminally Ill

With a high prevalence of HIV and AIDS in these regions, there has also been an increase in care needed for the terminally ill, and once again, it is the responsibility of the woman to provide the needed care (West & Hirsch, 2013). This involves emotional support, but also other aspects such as bathing and toileting. Providing this type of assistance can become more difficult when there is little accessibility to clean water. Furthermore, caregivers also have an increased chance of developing physical pain and infections because of the risks they are exposed to. Increasing accessibility to clean water will not only improve the outcomes of HIV treatment, but it will also reduce the burden of care on women. As a result, this can improve the quality of life for both groups (Figure 1).

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Figure 1: How improved water and sanitation influences the health of those with HIV/AIDS, and caretakers (West & Hirsch, 2013).

Overall, inaccessibility to clean water increases the emotional distress on women and reduces the level of care they are able to provide to those around them. When mothers have poor health status they are unable to provide the adequate resources needed for the well being of their children, which can lead to growth stunts (Requejo, et al., 2015).

Like any other public health issue, this one is complex. Many factors must be examined to determine how improvements can be made to increase the availability of safe water, while also empowering women. For example, while women have to travel long distances in order to get clean water, this also gives them a chance to socialize with other women and spend some time away from the home. Thus, what can be done to preserve this time for social interaction, while minimizing the health risks?  In order to answer this and similar questions, governments and NGOs must critically analyze social systems, specifically gender norms, health systems and physical infrastructure in low-resourced countries.

References:

Dora, C., Haines, A., Balbus, J., Fletcher, E., Adair-Rohani, H., Alabaster, G., et al. (2015). Indicators linking health and sustainability in the post-2015 development agenda. The Lancet , 385 (9965), 380-391.

Requejo, J. H., Bryce, J., Barros, J. A., Berman, P., Bhutta, P., Bhutta, Z., et al. (2015). Countdown to 2015 and beyond: Fulfilling the health agenda for women and children. The Lancet , 385 (9966), 466-476.

West, B. S., & Hirsch, J. S. (2013). HIV and H2O: Tracing the connections between gender, water and HIV. AIDS Behaviour , 17 (5), 1675-1682.  

The Role of the Built Environment in Reducing the Incidence of Type 2 Diabetes

~Written by Joann Varickanickal (Contact: joann.varickanickal@gmail.com)

Diabetes is a chronic disease that affects many people worldwide. Type 1 diabetes is an autoimmune deficiency that often develops in childhood and impacts about 10 percent of those with the disease (Canadian Diabetes Association, 2009). However, type 2 diabetes develops later in life, is influenced by environmental and lifestyle factors, and is prevalent among nearly 90 percent of those with diabetes.  While Type 2 diabetes used to be considered a “disease of the West”, it has now spread to more countries; thus, more efforts need to be made to reduce the incidence of this disease. As healthy diets and regular physical activity are key components to reducing the prevalence of type 2 diabetes, the built environment needs to be taken into consideration. The built environment includes all of the aspects of an environment created by humans, such as neighborhoods and cities, and consequently plays an important role in ensuring that people can access healthy food, and increase physical activity.

The Importance of Community Gardens

The accessibility of healthy foods can increase with the implementation of community gardens. Preliminary studies reveal several benefits of community gardens, including the associated increased intake of produce. One study examined the benefits of community gardens in South-East Toronto, concluding that those who participated in the maintenance of the garden increased their intake of vegetables and fruits and bought fewer produce from grocery stores (Wakefield, Yeudall, Taron, Reynolds, & Skinner, 2007). While these community gardens were established by non-governmental organizations, city planning officials still have a large role to play, as they could ensure that there is land in urban areas specifically designated for community gardens.   

Gardens could also be incorporated into schoolyards. One example of this was in California where the “Garden in Every School” program was implemented, and vegetables and fruits were grown on school property.  The kids helped to maintain the garden and this promoted healthy eating and an overall increase in the local food supply (San Mateo County Food System Alliance, 2010; Dannenberg, Frumkin, & Jackson, 2011).

The Role of Active Transportation

Encouraging physical activity is also a key component in reducing diabetes prevalence and this can be done through changes in the built environment by encouraging active transportaiton. This would involve increasing the walkability of communities through the implementation of pedestrian infrastructure, such as sidewalks and safe crossings, to ensure that these places are easily accessible.  

Encouraging “Smart Growth” would also be important. This concept was developed in the 1990s by initiatives that were being implemented by various organizations, including the American Planning Association (Dannenberg et al., 2011). “Smart Growth” policies encourage the preservation of open space, and making communities more walkable. This could be done through the implementation of mixed-land use development, which would ensure that employment, schools and shops were within close proximity and walking became one of the main methods of transportation.

Another key component of Smart Growth is developing a variety of transportation methods through the implementation of Transit-Oriented Development, which also became prominent in the 1990’s. This would be another way to encourage physical activity and reduce reliance on cars. Implementing bike lanes also encourages biking as a means of transportation. In Portland, Oregon there was an increase in biking after several miles of bike lanes were added, as a quadrupling in bikeway miles resulted in a quadrupling of bicycle bridge traffic (refer to Figure 1).

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Figure 1: An increase in bikeway miles in Portland, Oregon was led to an increase in bicycle traffic (Dannenberg et al., 2011).

There are other factors to consider when examining type 2 diabetes, such as biological factors among certain ethnic groups, and the difficulties associated with trying to make behavioural changes. However, by making sustainable changes to the built environment to increase accessibility to healthy foods and encourage active transportation, government officials and non-governmental organizations can begin to greatly reduce the prevalence of type 2 diabetes.  

References:

Canadian Diabetes Association. (2009). An economic tsunami of the cost of diabetes in Canada. Retrieved March 28, 2015, from http://www.diabetes.ca/CDA/media/documents/publications-and-newsletters/advocacy-reports/economic-tsunami-cost-of-diabetes-in-canada-english.pdf 

Dannenberg, A. L., Frumkin, H., & Jackson, R. J. (2011). Making Healthy Places: Designing and Building for Health, Well-Being, and Sustainability. Washington: Island Press.

Hu, F. B. (2011). Globalization of Diabetes: The role of diet, lifestyle, and genes. Diabetes Care , 34 (6), 1249-1257.

San Mateo County Food System Alliance. (2010). A Garden in Every School. Retrieved March 25, 2015, from Ag Innovations Network: http://aginnovations.org/images/uploads/call-to-action_GBL_final.pdf 

Wakefield, S., Yeudall, F., Taron, C., Reynolds, J., & Skinner, A. (2007). Growing urban health: Community gardening in South-East Toronto. Health Promotion Internationl , 22 (2), 92-101.