Poor childhood health caused by environmental factors, such as air pollution and exposure to toxic chemicals, cost the United States $76.6 billion in 2008, according to authors of a new study in the May issue of Health Affairs. This price tag represents a dramatic increase in recent years, rising from 2.8 percent of total health care costs in 1997 to 3.5 percent in 2008.

The new study by Leonardo Trasande of the Mount Sinai School of Medicine focused on the cost of lead poisoning, childhood cancer and chronic conditions, including asthma, intellectual disability, autism and attention deficit disorder-conditions that are linked to environmental toxins and pollutants in the air, food, water, and soil, as well as in homes and neighborhoods.

"Left unchecked, these preventable environmental factors will continue to harm the health of our children and push up health care costs," Trasande said. "By updating environmental regulations and laws aimed at protecting the public's health, we can reduce the toll taken by such factors on children's health and the economy."

Researchers used recent data to estimate the number of environmentally induced conditions in children and then calculated the annual cost for direct medical care and indirect costs, such as lost productivity resulting from parents' caring for sick children. They found that the aggregate cost of environmental illness in children was $76.6 billion in 2008 dollars.

The study provides an update to an analysis of 1997 data that documented $54.9 billion in annual costs of environmentally contributable childhood diseases in the United States. In comparing the two studies, researchers found that diminished exposure to lead and reductions in costs for asthma care were offset by diseases newly identified as environmentally induced, including attention deficit disorder, and the added burden of mercury exposure. This toxic metal, from contaminated fish and coal-fired power plants, can harm the developing brain and is associated with intellectual disability.

Key findings from the study:

- Lead poisoning cost $50.9 billion
- Autism cost $7.9 billion
- Intellectual disability cost $5.4 billion
- Exposure to mercury (methyl mercury) cost $5.1 billion
- Attention deficit hyperactivity disorder cost $5.0 billion
- Asthma cost $2.2 billion
- Childhood cancer cost $95.0 million

The authors call for further reductions in lead-based paint hazards to protect children from lead poisoning, which can severely affect mental and physical development, and tighter air quality standards to curb mercury emissions, as well as reduce particulates that can trigger asthma. They also call for testing of new chemicals and substances already in use to ensure they pose no risk to human health.

The study is part of a thematic issue that explores older environmental health problems that continue to plague the United States, as well as newer ones brought about by forces such as climate change. Funding for this issue is provided by The Kresge Foundation.

Several of the papers explore environmental health challenges for children, including the following:

Children's vulnerability to toxic chemicals

- A landmark 1993 study brought to the forefront the fact that children are far more sensitive than adults to toxic chemicals in the environment, write Philip Landrigan at the Mount Sinai School of Medicine and Lynn Goldman at the George Washington University. They analyzed existing literature on child toxicity, and conclude that even minute exposures to toxic chemicals-at levels that would have no impact on an adult-can harm children, leading to diseases like asthma, mental retardation, and possibly cancer. To reduce this burden of preventable disease, Landrigan and Goldman recommend including a legally mandated requirement to test the chemicals already on the market for toxicity and stepped-up research to both identify new toxins and document environmentally induced diseases in children.

Air pollution and its impact on health and academic achievement

- Perry Sheffield and coauthors at the Mount Sinai School of Medicine examined the little-studied relationship between fine particulates or pollutants in the air and the cost of bronchiolitis, a type of lung infection in children. They discovered that children exposed to such pollutants were more likely to have higher health care costs from treating this respiratory illness. If regulators took steps to reduce fine particulate levels 7 percent below the current standard, the nation would save an estimated $15 million a year in health care costs, the researchers note.

- Exposure to air pollution during important stages of development can lead to long-lasting health and academic problems for children. Paul Mohai, Byong-Suk Kweon, and their colleagues at the University of Michigan examined the extent of air pollution from industrial sources near public schools, finding that schools located in areas with the highest air pollution had the lowest attendance rates (a marker for poor health) and the highest proportion of students failing to meet state educational standards. The authors call for increased attention to the air quality in neighborhoods where schools are to be located.

Why environmental factors lead to increased disease rates

- Environmental toxins can change the way human genes work and lead to an increased risk of disease, say Kenneth Olden and coauthors at the City University of New York. The United States must start taking a cross-disciplinary approach to public health that would explore environment-gene interactions, say the authors. They call for increased scientific study of this phenomenon, which might lead to better ways to prevent and treat such illness.

Health Affairs