Health Canada  (Please see extracts and links below)

1- Health Risks of Community Noise: «The most common effect of community noise is annoyance, which is considered an adverse health effect by the World Health Organization. But noise may also affect your ability to have an ordinary conversation, enjoy some leisurely activities, get a good night's sleep, or do work that needs thought and concentration..»
htp://www.hc-sc.gc.ca/hl-vs/iyh-vsv/life-vie/community-urbain-eng.php

2- Recreational and Community noise : «Excessive exposure to noise, even for short durations, can have potential health effects. Significant, adverse, irreversible effects usually occur gradually in response to excessive exposure to noise.»
http://www.hc-sc.gc.ca/ewh-semt/noise-bruit/commun/index-eng.php

3- Traffic Noise Outside the Home: HealthInsider No. 8, December 2002
«More importantly,noise can cause stress. Like other sources of stress, it can temporarily affect the heart rate, blood flow and may also affect the immune system and the biochemistry of the blood.»
http://www.hc-sc.gc.ca/ewh-semt/pubs/noise-bruit/insider8/background-contexte-eng.php