“Killing you softly”Indoor air pollution: is cooking the

cause?

University of California, Irvine

School of Social EcologyRafael Rodriguez-Leal,

Undergraduate Research SymposiumMay 13 2006

The site: Comachuen

giragrupo interdisciplinario

de tecnología ruralapropiada

Michoacán

N

EW

S

Porcentaje de usuarios de leña para cocinar en Michoacán

Porcentaje3 - 1314 - 2728 - 4344 - 6263 - 81

Nahuatzen

100 0 100 200 Kilómetros

The Question

• Since most families cook different items with fire stoves, we analyzed the contribution of each meal, within the 95 percentile of peaks of PM and CO.

• We undertook this task by examining what items were cooked, and their contribution to pollutant concentrations, at the time they were cooked.

Food Types

• The population under study consumes a diversity of food types.

• The diet of the participants

Consists of mainly

beans, eggs, meat,

and tortillas.

Instruments

Definition of Terms

• PM: Particulate Matter

• CO: Carbon Monoxide

• Fdtype: Type of ingredient cooked

• 95 Percentile: The 5th % of the highest pollutant concentrations

Hypothesis

• H0: There won’t be a relationship between food items being cooked and pollutant levels regardless of fdtype

• H1: There will be a relationship between food items being cooked and pollutant levels, and they will vary according to fdtype

Methods

• Our sample consisted of 53 households• Continuous measurements of CO and PM

levels were taken over 48 hr. periods• A database in Excel was created

incorporating the measurements of both pollutants by minute.

• A database in Access was created to match cooked fdtypes to the highest pollutant peaks.

Methods

• The means of each fdtype were calculated when fdtype matched the 95 percentile in the peak considered

• The means of each fdtype matching the 95 percentile for all homes were calculated

Methods

• CO was measured in ppm

• PM was measured in mg/m^3

Tortillas Tortillas

Graph fdtype 6=meat, matching 95 percentile PM peak in home 17

0

1

2

3

4

5

6

7

8

9

10

12/1/2004 3:30:00 PM 12/1/2004 5:14:00 PM 12/1/2004 5:15:00 PM 12/1/2004 5:29:00 PM

time

pm

m

g/m

3

Graph fdtype 7=fish, matching 95 percentile PM peak in home 17

0

0.5

1

1.5

2

2.5

3

time

pm

mg/

m3

stpmb2df

Graph fdtype 8=milk , matching 95 percentile PM peak in home 17

0

0.5

1

1.5

2

2.5

3

3.5

4

12/1/2004 7:32:00 AM 12/1/2004 7:34:00 AM 12/1/2004 7:35:00 AM

time

pm

mg/

m3

stpmb2df

Graph fdtype 10=eggs , matching 95 percentile PM peak in home 17

0

2

4

6

8

10

12

14

16

18

time

pm

mg/

m3

stpmb2df

Graph fdtype 2=tortilla, matching 95 percentile CO peak in home 24

0

10

20

30

40

50

60

70

11/22/20046:40:00 PM

11/22/20046:45:00 PM

11/22/20046:46:00 PM

11/22/20046:47:00 PM

11/22/20046:48:00 PM

11/22/20046:49:00 PM

11/22/20046:50:00 PM

11/22/20046:51:00 PM

time

CO2

ppm stcob

Graph fdtype 2=tortilla, matching 95 percentile CO peak meal 2

0

10

20

30

40

50

60

time

CO

2 p

pm

stcob

Graph fdtype 4=beans, matching 95 percentile CO peak in home 64

0

10

20

30

40

50

60

time

CO

2

pp

m

stcob

Graph fdtype 6=meat, matching 95 percentile CO peak in home 91

0

20

40

60

80

100

120

time

CO

2

pp

m

stcob

Graph fdtype 6=meat, matching 95 percentile CO peak meal 2

0

10

20

30

40

50

60

70

time

CO

2

pp

m

stcob

Graph fdtype 10=eggs, matching 95 percentile CO peak in home 64

0

10

20

30

40

50

60

12/7/20042:18:00 PM

12/7/20042:19:00 PM

12/7/20042:26:00 PM

12/7/20042:27:00 PM

12/7/20042:28:00 PM

12/7/20042:29:00 PM

12/7/20042:30:00 PM

time

CO

2

pp

m

stcob

The Mean of all Homes

Fdtype No HomesAll Homes AVG PM No Homes

All Homes AVG CO

   

Tortillas 13 3.99 10 46.61

Eggs 3 3.66 1 45.38

Beans 3 5.09 3 54.28

Meat 4 6 4 49.24

Mean all Homes PM vs fdtype matchFdtype_PM_matching

0

1

2

3

4

5

6

7

2 4 6 10

fdtype

PM

m

g/m

^3

Series1

Mean all Homes CO vs fdtype matchFdtype_CO_matching

40

42

44

46

48

50

52

54

56

2 4 6 10

fdtype

CO

2 p

pm

Series1

Statistics

• H1Claim: For the population of homes using fire-stoves, the mean PM levels in 3 fdtype are given by µ≥2. Furthermore, for the population of homes using fire stoves, the mean CO levels in 3 fdtype is given by µ≥ 30.

• H0: PM µ<2 and CO µ<30

Statistics

• P-value method for testing hypotheses with a significance level of α=0.1

Ing PM mean

CO mean

PM P-test

CO P-test

Outcome

tortilla 3.99 46.61 .0256<.05

p<α

.0030<.05

p<α

Significant

beans 5.09 54.28 .004<.05

p< α

.0022<.05

p< α

Significant

meat 6.00 49.24 .0122<.05

p< α

.0071<.05

p< α

Significant

Ing PM

σ

CO

σ

- - -

tortilla 4.95 29.61 - - -

beans 5.71 41.63 - - -

meat 8.76 37.74 - - -

GraphGraphKitchen CO and PM concentrations with a traditional stove (Fogon)

0

20

40

60

80

100

120

140

0 300 600 900 1200 1500 1800 2100 2400 2700 3000

Number of minutes

CO

(p

pm

)

0

20

40

60

80

100

120

140

160

180

200

PM

(mg

/m3)

HOBO CO

UCB PM

Milk for children

Tortilla’s making

breakfastmeal

Tortilla´s making

Conclusions

• The present study considers that there is a significant contribution to indoor air pollution levels, caused by the cooking of different fdtypes

• There is variation in the concentrations of pollutants emitted, depending on the fdtype being cooked

Further Research Needed

• To examine the possibility of a diet modification in the population studied.

• Search to what extent the fdtypes that are cooked most of the time, contribute more or less to pollutant concentrations, vs. the fdtypes that aren’t cooked most of the time.

Acknowledgements

• Ph.D. candidate Michael A. Johnson• Professor & Adviser Ph.D. Rufus Edwards• Social Ecology Honors Seminar: Professor & Chair Ph.D. Valerie Jenness• Air Pollution Lab Team: Nick Lam, and

Erin Milner

CONTACT INFO

• Rafael Rodriguez-Leal Torres

• Undergraduate • Environmental Analysis & Design• University of California, at Irvine• Social Ecology

• rafaelsr@uci.edu• mobile: 949 551 6484

THANK YOU FOR YOUR TIMETHANK YOU FOR YOUR TIME

YOU HAVE BEEN A TERRIFIC CROUDYOU HAVE BEEN A TERRIFIC CROUD YOUR PATIENCE IS APPRECIATEDYOUR PATIENCE IS APPRECIATED

GOOD LUCK AT THE SYMPOSIUM!!!!GOOD LUCK AT THE SYMPOSIUM!!!!

APL ROCKS!!!!!APL ROCKS!!!!!