Who is more vulnerable to environmental hazards?

This section identifies population groups who are more vulnerable to environmental hazards in Aotearoa New Zealand. This type of information can help to develop strategies, policies and measures, to lessen the impacts.

Who is more vulnerable?

Some population groups may be more vulnerable to the negative impacts of an environmental hazard on their health or wellbeing. Being more vulnerable means that people are more likely to experience negative impacts if they are exposed to an environmental hazard, compared with other people.

Environmental hazards include air pollution, water pollution, and mosquito-borne diseases, among others. Other relevant hazards may include climate-related hazards (eg heatwaves, floods, extreme weather events) and natural hazards (eg earthquakes).

Vulnerable population groups have a higher risk of experiencing negative impacts from environmental hazards. People can be more vulnerable to environmental hazards if they are [1,2]:

• more exposed to environmental hazards
• more sensitive to the effects
• less able to anticipate, cope with, or recover from the effects.

Vulnerability can be due to age (eg young, old), having pre-existing health conditions, and/or socio-demographic characteristics and circumstances [1,2,3,4]. Potentially vulnerable populations include:

• infants and children
• older adults
• people with lower socioeconomic status 
• people with a chronic health condition
• people with a disability. 

Other population groups may also be more vulnerable, depending on the hazard and circumstance. These population groups include people living in urban areas, people living in rural areas, people working in certain occupations, Māori, Pacific peoples, and people of other ethnic minorities. 

Understanding population vulnerability is important to ensure that the needs of vulnerable population groups are considered in planning and decision-making. This enables exposure to environmental hazards to be prevented or avoided where possible, or, if not possible, their impact can be minimised. Identifying vulnerability also enables resources to be directed more effectively to those who have the greatest need [1].

A wider range of factors can also influence people's vulnerability to climate-related hazards and natural hazards (see the social vulnerability webpages for more information).  

Infants and children

Infants and children are more susceptible than adults to a range of environmental hazards.

• Young children (under five years) have limited mobility. They depend on others to move them out of dangerous situations.
• Young children are less able to perceive risk.
• Young children’s behaviour includes lots of hand-to-mouth activity and play close to the ground, which exposes them more to some hazards (eg lead from soil) [5,6,7].
• Children are still developing and growing, which makes them more susceptible to toxins and illness.
• Children’s breathing rate is higher than adults, making them more susceptible to air pollution.
• Children’s younger age and longer life expectancy means that they may yet be affected by some hazardous substances with long lag (latency) periods.

Pregnant women and their unborn children may also be at increased risk from environmental hazards.

For population statistics about children, go to the age profile webpage.

Older adults

Older adults (aged 65 years and over) can be more affected by environmental hazards.

• Older adults may have limited mobility, strength and balance. They are also more likely to have poor eyesight and hearing. This means they are in one place for longer periods, and may depend on others to move them out of hazardous areas [4,7]. 
• Older adults have higher rates of chronic disease, which can make them more sensitive to environmental hazards like air pollution and infectious diseases. 
• Older adults are more susceptible to dehydration on very hot days, and the effects of cold weather.

In particular, older people who live alone may be at more risk from hazards, especially if they don’t have other people to help them if needed [8].

For population statistics about older adults, go to the age profile webpage.

People with lower socioeconomic status

People with lower socioeconomic status often have less capacity to cope with the effects of environmental hazards. For example, people on low incomes may be more likely to live in a hazard-prone environment, for example on marginal land and/or in poor quality, overcrowded housing. They may not have the financial means to move away, or to take action to reduce exposure to environmental hazards. 

The New Zealand Index of Deprivation (NZDep) provides a summary deprivation score for small areas (SA1s, SA2s, and census area units) [9]. NZDep can be used to identify areas where people experience higher levels of socioeconomic deprivation.

NZDep Index incorporates low income, as well as a range of other socioeconomic factors (such as people who are renting, unemployed, lack qualifications, single-parent families, no access to a vehicle).

For statistics about socioeconomic deprivation and NZDep, go to the socioeconomic deprivation profile webpage.

People with a chronic health condition

People with chronic health conditions may be more susceptible to environmental hazards. Health conditions that may increase people's susceptibility include:

• cardiovascular diseases, such as heart disease and stroke
• respiratory diseases, such as asthma and chronic obstructive pulmonary disease (COPD)
• diabetes
• psychological distress
• immune deficiency, such as organ transplant or HIV infection.

People with a chronic health condition may be at increased risk from environmental hazards, such as:

• infectious diseases, due to weak body defences
• effects of air pollution, as their lungs are already working hard to cope at 'normal' levels of air pollution (this particularly affects people with respiratory disease and cardiovascular disease)
• skin cancer (among people with low immunity).

For statistics about people with a chronic health condition, go to the people with a chronic health condition or disability webpage.  

People living with a disability

A person living with a disability cannot always easily carry out day to day tasks. People living with a disability may be more susceptible to environmental hazards and may find it more difficult to respond to them. They may also be more socially isolated and have a lower income due to their disability [10], which can increase vulnerability. Living with a disability can include having:

• a physical impairment that limits day to day activities
• a sensory impairment, for example poor vision or hearing
• learning difficulties
• a psychological or psychiatric impairment.

For statistics about people living with a disability, go to the people with a chronic health condition or disability webpage. 

Māori and Pacific peoples

Māori may be more vulnerable to environmental hazards, similar to indigenous populations in many other countries. Pacific peoples may also be more vulnerable to environmental hazards in New Zealand than other ethnic groups.

Much of these differences are driven by inequities. These inequities include structural and systemic inequities, disadvantage leading to increased exposure to hazards, and vulnerability due to poor or inadequate policies to protect health. For example, Māori and Pacific peoples experience: 

• higher levels of exposure to environmental hazards, such as air pollution in urban environments, higher levels of household crowding, and second-hand smoke exposure 
• disproportionately low incomes, leading to less capacity to reduce exposure to environmental hazards and/or to respond to these hazards
• reliance on primary industries: the Māori economy is especially reliant on primary industries like farming, which are sensitive to climate change [11].
• higher levels of some chronic diseases, which can increase susceptibility to certain health impacts from environmental hazards.

For population statistics about Māori, Pacific peoples and other ethnic groups, go to the ethnic profile webpage. 

Living in urban and rural areas

People living in rural areas may be more vulnerable to certain environmental hazards. They are more likely to work in primary industries, such as forestry and farming, which are more susceptible to climate change [11]. People working with animals may also be more exposed to infectious diseases such as leptospirosis, which can be passed through animal urine. People in rural areas may also have less access to services such as shops, health clinics and emergency response services (police, fire and ambulance).

However, people in urban areas may be more exposed to other environmental hazards, such as air pollution and heatwaves (due to urban heat island effects).

For more information on living in urban and rural areas, go to the urban-rural profile webpage.