NIH-led Research Group Links Climate Changes, Human Health Impact

Foodborne diseases and nutrition. Drought has been shown to encourage crop pests such as aphids, locusts, and whiteflies, as well as the spread of the mold Aspergillus flavus that produces aflatoxin, a substance that may contribute to the development of liver cancer in people who eat contaminated corn and nuts.

Weather related morbidity and mortality. A changing climate, coupled with changing demographics, is expected to magnify the already significant adverse effects of extreme weather on public health. For example, the intensity and frequency of precipitation events in the United States have increased over the past 100 years in many locations.

Heat related morbidity and mortality. Factors such as age and the burden of other serious illnesses such as heart disease and diabetes that might exacerbate heat related problems are critical. In the U.S., the number of individuals 65 years of age and older—who are more susceptible to heat effects—is expected to increase from 12.4% in 2000 to 20% in 2060.

Vectorborne and zoonotic diseases. This includes diseases, such as malaria, which can be transmitted from animals to humans. A "severe degradation" of rural and urban climate and sanitation conditions could bring malaria, epidemic typhus, plague, and yellow fever "to their former prominence."

Human developmental effects. The environment can be a "potent modifier" of normal development and behavior, according to the report. Environmental effects on development include subtle changes such as small reductions in IQ from exposure to lead, changes in onset of puberty from exposure to endocrine disrupting chemicals, and birth defects such as cleft palate due to dioxin like compounds.