Health impacts of air pollution

Life and Breath Report: Air pollution contributes to early deaths and hospitalizations

View the full report
Life and Breath 2019


Air quality in Minnesota currently meets federal standards, but even low and moderate levels of air pollution (that you can't always see) can contribute to serious illnesses and early death. The recent Life & Breath report estimates the impact of two common air pollutants in Minnesota, fine particle pollution (PM2.5) and ground-level ozone. The findings provide a sense of the magnitude of the health risks related to air pollution. WSpecifically, using mathematical models we calculated respiratory and cardiovascular hospital admissions, emergency department visits, and early deaths impacted by air pollution across the state.

The results presented here are not counts of specific individuals, but rather estimates of health impacts attributable to air pollution for whole populations. We used mathematical models with inputs (from large scale epidemiology studies) and these data are not to be taken as exact numbers of heart and lung hospitalizations, emergency room visits or deaths caused by air pollution alone. The estimates are meant to provide a better understanding about health impacts due to air pollution exposure and are not based on tracking individual level exposures and health outcomes.

Overall, we estimate that in 2013 across Minnesota:

  • Between 5 and 10 percent of all residents who died, and 1 to 5 percent of all residents who visited the hospital or emergency room for heart and lung problems, did so partly because of fine particles in the air or ground-level ozone.
  • This is roughly 2,000 to 4,000 deaths, 500 additional hospital stays, and 800 emergency room visits.

In addition, we estimated how many health impacts could be avoided from a ten percent decrease in ambient air pollution. MDH and the Minnesota Pollution Control Agency (MPCA) are using the information provided in this report to raise awareness about air pollution and health, inform pollution reduction and health promotion programs, and work with partners to advance environmental justice and health equity.

Mapping the data

The underlying rate (presented here) is the overall impact of health-related events in a population (the rate from all causes). The attributable rate (a subset of the underlying rate) is the estimated rate due to air pollution. This is a good measure of a population’s overall vulnerability to air pollution, whether due to differences in air pollution or in the health of a community (underlying health inequities). A population-based rate helps to make clear comparisons between counties or groups of differing sizes.

 

Attributable death rate by county, ages 25 years and older: fine particles

In 2013, fine particle pollution (PM2.5) contributed to an estimated 2,000 to 4,000 deaths, 300 respiratory hospitalizations, 140 cardiovascular hospitalizations, and 525 asthma-related ED visits in Minnesota. The largest impact from fine particle pollution is early death, with up to 10 percent of deaths state-wide due in part to fine particle pollution.

Attributable cardiopulmonary death rate, by county

 

In 2013, summertime ground-level ozone pollution contributed to an estimated 57 cardiopulmonary deaths, 55 asthma hospitalizations, and close to 300 asthma-related ED visits (Table 3). By reducing ground-level ozone by ten percent from 2013 levels, 18 deaths, 17 asthma-related hospitalizations, and close to 95 asthma ED visits could have been prevented.


Health equity

Who is most affected and where?

  • Seniors, children, and people with pre-existing heart and lung conditions are affected more than others. 

  • Low-income counties with more uninsured people and older populations are most vulnerable to the health impacts of air pollution.

  • Both underlying health conditions and structural inequities (such as policies, programs, decision making, governance and economics) influence how health is affected by air pollution. 

Respiratory and cardiovascular hospitalization rates attributable to fine particles, ages 65 and older

Fine particle matter and ozone attributable mortality, by percent poverty statewide

 
 
 
 
 

Fine particle matter and ozone attributable mortality, by percent without insurance statewide

 
 
 
 
 

 

We estimated areas with higher rates of uninsured residents had increasing death rates attributable to fine particle and ozone pollution. Similar to results for county poverty rates, this pattern reflects how the underlying burden drives the increase in risk of early death.


Statewide results summary

Health Effect
(age group)
Attributable Number
(95% CI)*
Percent of Total Events
(95% CI)*
Attributable rate per 100,000 people
(95% CI)*
All-cause deaths**
(25 and older)

(30 and older)
4,098.0
(2,098.0 - 5,983.0)
10.20%
(5.2% - 14.9%)
112.8
(57.8 - 164.7)
1,866.0
(1,270.0 - 2,449.0)
4.70%
(3.2% - 6.2%)
57.1
(38.9 - 75.0)
Asthma hospitalizations
(under 18)
15.0
(0 - 74.0)
1.70%
(0% - 8.8%)
1.1
(0 - 5.8)
Asthma and COPD hospitalizations
(18 to 64)
64.0
(21.0- 99.0)
1.80%
(0.6% - 3.0%)
1.8
(0.6 - 2.9)
All respiratory hospitalizations
(65 and older)
249.0
(144.0 - 352.0)
1.70%
(1.0% - 2.5%)
33
(19.1 - 46.7)
Asthma emergency department visits
(all ages)
525.0
(146.0 - 896.0)
2.40%
(0.7% - 4.1%)
9.7
(2.7 - 16.5)
Cardiovascular hospitalizations
(65 and older)
140.0
(53.0 - 226.0)
0.60%
(0.2% - 0.9%)
18.6
(7.0 - 30.0)
*95% confidence intervals. These intervals are within which the true value is expected 95 out 100 times.
** Represents two peer reviewed studies of the relationship between fine particle pollution and early deaths—the Harvard 6-Cities study and the American Cancer Society study.

 

Key findings: A reduction in 10% in 2013 fine particle pollution levels could prevent up to 500 deaths, 50 hospitalizations, and 60 emergency room visits while fulfilling Clean Air MN goals, resulting in a significant public health impact across Minnesota.

 

Health Effect
(age group)
Attributable Number
(95% CI)*
Percent of Total Events
(95% CI)*
Attributable rate per 100,000 people
(95% CI)*
Cardiopulmonary deaths 56.8 1.00% 1.0
(21.3 - 91.8) (0.4% - 1.7%) (0.39 - 1.69)
Asthma hospitalizations 54.6 4.80% 1.0
(33.8 - 74.9) (3.0% - 6.6%) (0.6 - 1.4)
Asthma emergency department visits 298.0 3.20% 5.5
(0 - 648.0) (0.0% - 6.9%) (0 - 12.0)
*95% confidence intervals. These intervals are within which the true value is expected 95 out 100 times.

 

 

 

Key findings: A reduction of 10% in 2013 ozone pollution levels could prevent up to 20 cardiopulmonary deaths, 20 hospitalizations, and 100 emergency room visits.

What is being done about air pollution and its health impacts?

These study results, other MPCA and MDH analyses and meaningful stakeholder engagement will help us direct pollution reduction resources. This can help address environmental justice and health equity goals, including inequities like air pollution and access to health care. Recent progress includes Environmental assistance grants from the MPCA, such as the Volkswagon Settlement, and MDH programs like the Eliminating Health Disparities Initiative.

This study is the result of a collaboration between MDH and MPCA. The complete Life and Breath Report can be found on the Minnesota Pollution Control Agency (MPCA) website.

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