The objective is to evaluate the behavior of inequities present in health damage due to effects of exposure to particulate matter of 10 microns. It is a non-experimental longitudinal ecological study using records of hospitalizations of under 5-year-old children. The identification of socio-economic groups (GSE) is obtained by using categories of beneficiaries of the health system. The presence and magnitude of health inequities are calculated by means of rates of hospitalization (RH), relative risk (RR), gradient of inequality (m) and a normalized scatter plot between m and the total value of RH. The results show inequity in the effects of pollution on the health of residents in different municipalities of the city of Santiago de Chile. The risk of becoming ill and requiring hospital care increases with decreasing the GSE.