Children who live within 11 kilometers of the Salton Sea, a drying body of water with a high concentration of salts and contaminants in Imperial Valley, California, have slower lung function growth between ages 10 and 12 than children who live farther away. The impact is comparable to living within 500 meters of a freeway and could affect respiratory health into adulthood. The Keck School of Medicine team worked with Comité Civico del Valle, a longstanding local community organization, to recruit children for the first long-term health study in the region. Researchers followed 369 children, whose average age was 10 when the study began, for roughly two years. Lung function was measured in two ways: forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). FVC measures how much air the lungs can expel after a deep breath and FEV1 tests how quickly that air can be pushed out of the lungs. Taken together, these measures help show whether or not air is flowing normally through the lungs. The researchers also calculated the distance between each child’s home and the Salton Sea and obtained data on fine particle pollution and spikes in dust levels from local air quality monitors. In their analysis, they controlled for the effects of age, sex, ethnicity, socioeconomic status, height, body mass index and respiratory health at the beginning of the study. Children who lived within 11 kilometers of the Salton Sea had 52.18 milliliters per year lower growth in FVC and 38.7 milliliters per year lower growth in FEV1 than children who lived farther away. More hours of exposure to high dust levels were also linked to lower FVC and FEV1 growth, especially for children living closer to the Sea. Their findings on lung function patterns over time could have implications well beyond Imperial Valley, as drought and rising temperatures cause other lakes, such as the Great Salt Lake in Utah and the Aral Sea in Central Asia, to shrink and emit dust. Lung function typically undergoes a growth spurt in adolescence, then peaks in young adulthood. More research is needed to understand what happens when development is interrupted, but ongoing problems with lung capacity could have lasting health consequences.
