Int. J. Environ. Res. Public Health 2010, 7 3464 less successful at controlling extraneous sources of noise and interruptions in the noisy school than in the quiet school. We were able to add a covariate to control for some of the variance associated with these problems, but it is still possible that variations in the testing environments attenuated some of the effects due to imperfect measurement of ambient conditions during testing at the schools. 5. Conclusions The present results suggest a possible link between chronic noise exposures related to street traffic surrounding elementary schools and diminished blood pressure responses to acute noise and non-noise stressors in elementary-school-aged children. There was no evidence of a link between chronic noise exposure at school and resting blood pressure. In general, data on road traffic noise and blood pressure are equivocal. Since work on aircraft noise and blood pressure is more consistent, at a minimum the noise source as well as its intensity needs to be considered in evaluating the effects of noise on blood pressure. Although not a focus of the present study, we also found that chronic noise exposure at school may be a risk factor for obesity, as evidenced by the significantly higher BMI among children in the noisy versus quiet school. In rapidly developing and highly populous countries, such as India, chronic noise problems will continue to grow exponentially and affect many thousands if not millions of children. Further research is need to establish the long-term and clinical significance of the effects of noise in this context given the vast numbers of people likely to be affected in coming decades. Acknowledgements References The authors are thankful for the research assistants, school administrators, teachers, and children who helped with this study. We also thank Madan Palsane for his helpful comments on the study design. An Indo-American Fellowship co-sponsored by the National Science Foundation and the Fulbright Association awarded to Stephen J. Lepore supported this work. 1. 2. 3. 4. 5. 6. 7. Evans, G.W.; Lepore, S.J. Nonauditory effects of noise on children: A critical review. Children's Environments 1993, 10, 31-51. Evans, G.W. Child development and the physical environment. Annu. Rev. Psychol. 2006, 57, 423-451. Evans, G.W.; Lercher, P.; Meis, M.; Ising, H.; Kofler, W.W. Community noise exposure and stress in children. J. Acoust. Soc. Am. 2001, 109, 1023-1027. Cohen, S.; Evans, G.W.; Stokols, D.; Krantz, D.S. Behavior, Health, and Environmental Stress; Plenum: New York, NY, USA, 1986. Evans, G.W.; Bullinger, M.; Hygge, S. Chronic noise exposure and physiological response: A prospective study of children. Psychol. Sci. 1998, 9, 75-77. Maschke, C.; Rupp, T.; Hecht, K. The influence of stressors on biochemical reactions—A review of present scientific findings with noise. Int. J. Hyg. Environ. Health 2000, 203, 45-53. Matthews, K.A.; Salomon, K.; Brady, S.S.; Allen, M.T. Cardiovascular reactivity to stress predicts future blood pressure in adolescence. Psychosom. Med. 2003, 65, 410-415.