Cognitive Impact on Children from Airplane Noise

2008

Outline

Concepts and Definitions General Health Effects School Studies Conclusions and Future Actions

Concepts and Definitions

NOISE = UNWANTED SOUND

Measurements

Measured as oscillation of air pressure (scientific) and unwanted (value judgment)

The intensity of sound waves produce a sound pressure level which is measured in the Decibel (dB)

Db use a logarithmic scale to accommodate the large range of values a human ear can detect.

Increase of 3-5 dB is significant Increase of 10 dB is a doubling of sound Increase of 15 dB is four times as loud

Noise Guidelines

FAA level of significance: compatible with residential commercial, public building use 65 db

EPA outdoor for protection of public health and wellfare 55 db

WHO outdoor day 50-55 db

Metropolitan area noise 45-60 db

Studies show cognitive impacts starting around 50-55 db

EPA indoor 45 db

WHO outdoor night 45 db

Typical background even in rural suburban area 40 db

Bedrooms 30 db

Sources of Noise

Weighted Sound Measurements

Day night sound level – Ldn- (weigthed over 24 hr period with a 10dB penalty for night time hours where annoyance may be highest)

The average increase in air craft noise within the Redesign Area is estimated at 4.5 – 5.9 dB

Health Effects

The reported non-auditory effects in noise range from social psychological effects such as annoyance, effects on mental health, effects on sleep, effects on performance to stress related health effects such as hypertension and ischaemic heart disease. Exposure to noise constitutes a health risk. (Health Council Netherlands)

Health Effects

Annoyance/Stress Hypertension (HYENA) Sleep Disturbances Hearing loss Effects on learning

Cognitive Impacts on Children

The School StudiesLos AngelesMunichLondonRanch (Road traffic and air noise exposure and

childrens cognition and health)FICAN (Federal interagency commission on aviation

noise)

Study LA-1981 Munich-1998 London-2003

RANCH-2005(roadtraffic and air noise exposure and childrens cognition and health)

FICAN (fedral interagency commission on aviation noise)

Setting

4 high noise and 3 low noise schools flight path of LAX with follow up one year later

prospective study. Shut down old air port in urban area and open new one in rural area. Selected schools by old air port in noise and quiet zones and schools by new airport in noise and quiet zones

cross sectional study: 10 high noise and 10 low noise schools by Heathrow air port

cross sectional and transnational. Amsterdam, Madrid, and London airports, as well as data from Sweden. 3000 children

32 public schools by 3 air ports. Used available data, standardized tests etc. Looked at noise during school year. And schools before and after noise reduction.

Quality of life

 

significantly worse 18 months after new airport opened. Findings stable in the quiet communities.

higher measures of annoyance in the high noise schools

non-linear exposure response between noise at school and home and annoyance. High aircraft noise exposure equals greater annoyance.

 

Motivation and helpless ness

children from the high noise school more likely to give up

noise area children were more likely to give up on tasks the second time whether or not they failed the first time.

     

Blood pressure

increase in both systolic and diastolic readings in children from noise schools

not statistically significant  

aircraft noise in school not related to blood pressure. Aircraft noise home significant to systolic but not diastolic or heart rate.

 

Reading  

significant difference between noise and quiet for old air port area for the difficult passages in reading tests

no difference between exposure levels on the test as a whole but if look at the 15 most difficult items then significant difference between noise and quiet.

linear exposure effect w reading, especially complex questions, episodic memory and working memory. Increase of 5 db equals 1-2 month delay in reading.

high school verbal test failure rates dropped 12%, lesser effect in math. No other statistical significant effects.

Dose Response

Conclusions

Chronic exposure to air craft noise impairs reading and ability to perform complicated tasks

Linear exposure effect response seen at 5db increases

Increase of 5 dB leads to 1-2 month delay in reading

Effect of noise is cumulative Reduction in noise lead to reduction in

impairment. Or the effect of noise on cognitive abilities appears to be reversible

Aviation Noise Impacts Community impacts:

The increase of 3-5 dB in a community will be experienced as a doubling in noise

Sound quality in a community can add or detract to the sense of social well being

Public health impacts: Increased levels in hyper tension and stress hormones as

well as sleep interruption can lead to other more serious health problems

Cognitive impacts: Decreased cognitive function in children can have

significant impact on test scores, school funding, and future learning

Future Actions

Is the FAA using the right metrics? Alternatives to the day-night average Alternatives to the FAA 65 dB threshold Take susceptibility into account

Dose response Cognitive impacts Health impacts

Treat noise as an independent environmental stressor