Kevork Djansezian / Getty Images A playground at the Carson-Gore Academy of Environmental Sciences in Los Angeles. The $75.5-million elementary school, which was named after former Vice President Al Gore and pioneering environmentalist Rachel Carson, was built atop an environmentally contaminated piece of real estate. Construction crews replaced the toxic soil, which was poisoned by more than a dozen underground storage tanks, with clean fill.

A landmark Environmental Protection Agency report concluding that children exposed to toxic substances can develop learning disabilities, asthma and other health problems has been sidetracked indefinitely amid fierce opposition from the chemical industry.

America’s Children and the Environment, Third Edition, is a sobering analysis of the way in which pollutants build up in children’s developing bodies and the damage they can inflict.

The report is unpublished, but was posted on EPA’s website in draft form in March 2011, marked “Do not Quote or Cite.” The report, which is fiercely contested by the chemical industry, was referred to the White House Office of Management and Budget (OMB), where it still languishes.

For the first time since the ACE series began in 2000, the draft cites extensive research linking common chemical pollutants to brain damage and nervous system disorders in fetuses and children.

It also raises troubling questions about the degree to which children are exposed to hazardous chemicals in air, drinking water and food, as well exposures in their indoor environments – including schools and day-care centers – and through contaminated lands.

In the making since 2008, the ACE report is based on peer-reviewed research and databases from federal agencies, including the Food and Drug Administration, Housing and Urban Development and the Centers for Disease Control and Prevention.

Public health officials view it as a source of one-stop shopping for the best information on what children and women of childbearing age are exposed to, how much of it remains in their bodies and what the health effects might be. Among the “health outcomes” listed as related to environmental exposures are childhood cancer, obesity, neurological disorders, respiratory problems and low birth weight.

The report cites hundreds of studies -- both human, epidemiological studies that show a correlation between exposure to certain chemical pollutants and negative health outcomes, and animal studies that demonstrate cause and effect. In some cases, the authors note, certain chemicals have been detected in children, but not enough is known about their effects to draw conclusions about safety.

In a section on perfluorochemicals (PFCs), for example, which are used to make nonstick coatings, and protect textiles and carpets from water, grease and soil, among other things, the draft notes that they are found in human breast milk.

The report said that “a growing number of human health studies” have found an association between prenatal exposure to PFCs and low birth weight, decreased head circumference and low birth length. It also stated that based on “emerging evidence suggests that exposure to some PFCs can have negative impacts on human thyroid function.”

Furthermore, it noted that animal studies produced similar results, although exposures were typically at higher levels than people are exposed to.

The EPA’s website still notes that the report will be published by the end of 2011. But after a public comment period that was marked by unusually harsh criticism from industry, additional peer review and input from other agencies, the report landed at OMB last March, where it has remained. No federal rule requires the OMB to review such a report before publication, but EPA spokeswoman Julia Valentine said the agency referred it to the OMB because its impact cuts across several federal agencies.

The spokeswoman said EPA had no idea when OMB would release it, allowing publication.

A spokeswoman for the White House Office of Management and Budget said she would not discuss the review process or give an estimated release date.

Some present and former EPA staffers, who asked not to be named for fear of losing their jobs, blamed the sidetracking of the report on heightened political pressure during the campaign season. The OMB has been slow to approve environmental regulations and other EPA reports throughout the Obama Administration — as it was under George W. Bush according to reports by the Center for Progressive Reform, a nonprofit consortium of scholars, doing research on health, safety and environmental issues, which generally advocate for stronger regulation and better enforcement of existing law.

“Why is it taking so long? One must ask the question,” said a former EPA researcher who works on children’s health issues. “It is an important document and it strikes me that it’s falling victim to politics.”

The EPA states that the report is intended, in part, to help policymakers identify and evaluate ways to minimize environmental impacts on children.

That’s an unwelcome prospect to the $674 billion chemical industry, which stands to lose business and face greater legal liability if the EPA or Congress bans certain substances mentioned in the report or sets standards reducing the levels of exposure that is considered safe.

Among other findings, the report links numerous substances to ADHD, including certain widely available pesticides; polychlorinated biphenyls (PCBS), which were banned in 1979 but are still present in products made before then and in the environment; certain polybrominated diphenyl ethers (PBDEs), used as flame retardants; and methyl mercury, a toxic metal that accumulates in larger fish, such as tuna. The draft also cites children’s exposure to lead, particularly from aging lead water pipes, as a continuing problem (See previous coverage, Toxic Taps.)

Among the other widespread contaminants linked to learning disabilities is perchlorate, a component of rocket fuel , fireworks and other industrial products, which has polluted water around the country. The Department of Defense, which wants to avoid paying to clean it up, is alarmed by research showing that the chemical interferes with thyroid function and otherwise damages the nervous system, according to R. Thomas Zoeller, a biology professor at the University of Massachusetts Amherst, and an expert on perchlorate.

Zoeller, who has served on EPA advisory panels studying the issue, said the Pentagon’s concern was evidenced by the Air Force’s hiring of two consultants – Richard Mavis and John DeSesso -- to help shape its response to the research. He noted that in 2009, after their consulting contract had ended, Mavis and DeSesso wrote a letter to the editor of Environmental Health Perspectives, a publication of the National Institute of Environmental Health Sciences, attacking an EPA scientist’s study showing that perchlorate may damage the brain. “I don’t like my tax dollars going for one federal agency to refute the work done by scientists at EPA,” he said. The Defense Department and the Air Force declined to comment on the publication, but spokeswoman Melinda Morgan wrote that, “The DoD is aware that there are many differing opinions on the science related to perchlorate health effects,” and believes the current level permitted by EPA is safe.

One of the new sections of the report notes that children may be widely exposed to pollutants in schools and day-care centers. Among them are pesticides; lead; PCBs; asbestos, a mineral fiber long used as insulation and fire-proofing; phthalates, chemicals that are used to soften vinyl and as solvents and fixers, and are found in numerous consumer goods, among them: toys, perfumes, medical devices, shower curtains and detergents; and perfluorinated chemicals, which are used in non-stick and stain-proof products. The study notes that these substances are (variously) associated with asthma, cancer, reproductive toxicity and hormone disruption.

The American Chemistry Council (ACC) , the chief industry trade group, has accused EPA of lacking objectivity and vilifying its products. It has filed dozens of pages of comments accusing the EPA of ignoring certain studies – including some funded by ACC itself — that would help businesses make the case that their products are safe. The ACC also contends that EPA has not included enough positive comments about the role of chemicals in society.

“ACC members apply the science of chemistry to make innovative products and services that make people’s lives better, healthier and safer,” wrote ACC senior toxicologist Richard A. Becker. … “The exclusive focus on exposure is particularly problematic as it may lead to the incorrect conclusion that exposure to chemicals (e.g. phthalates) at any level is not only cause for concern, but also a direct source of negative health effects.”

Becker also expressed the ACC’s contention that EPA was painting too bleak a picture of children’s health in America.

“It is troubling that the draft ACE report seems to make such little effort to provide a complete overall picture of child health in the United States,” Becker wrote. “For example, the draft report does not refer to The Health and Well-Being of Children: A Portrait of States and the Nation … which concludes the health and well-being of children in the U.S. is improving overall with 84.4% of children in the United States listed as being in excellent or very good health, an increase from 83% in 2003.” Other ACC members, representing manufacturers of BPA, phthalates and other substances, also weighed in against the report.

Nsedu Witherspoon, executive director of the Children’s Environmental Health Network and a member of the EPA Children’s Health Protection Advisory Committee, which oversaw the report, called it a major accomplishment, reflecting the explosion of science since the first ACE was published. She also praised EPA chief Lisa Jackson for standing behind it.

Industry critics, Witherspoon said, “in many cases are the same ones out there trying to debunk the original research,” that the study cites.

Rena Steinzor, a professor at the University of Maryland School of Law, and president of the Center for Progressive Reform, said the ACE report need not have gone to OMB for review in the first place. Steinzor notes that Executive Order 12866 states that proposed significant regulations — generally defined as those that could cost more than $100 million — need be reviewed by OMB, but studies do not.

The Executive Order gives OMB up to 60 days to review such proposals — although it allows for extensions. In practice, OMB has missed numerous such deadlines. But the ACE report, which is not a proposed regulation, falls into a gray area.

“If it’s not a rule, I don’t know what it’s doing there,” Steinzor said. “And even if it were a rule, there would be a deadline and they’d be violating it.”

In an email statement to the Investigative Reporting Workshop, EPA spokeswoman Julia Valentine said, “The report was provided to OMB so that they could conduct an interagency review process to ensure accuracy and consistency.”

She noted that because the report addresses children's health, it includes issues that are the focus of many departments and agencies within the Department of Health and Human Services -- including the Centers for Disease Control, the Food and Drug Administration, the National Institute of Environmental Health Sciences and the National Cancer Institute.

Steinzor, whose organization has studied OMB under numerous presidents, doesn’t buy it.

The report should be released now, she said, “ because to protect children adequately we need all the information we can get… I guess I understand why there was great anxiety and paranoia before the election … (but) why would you not do it now? It’s sad that things have gotten so polarized that we’re afraid to release scientific information.”

The Investigative Reporting Workshop at American University, is a nonprofit, professional newsroom that pairs experienced professional reporters and editors with graduate students, and co-publishes with mainstream media partners and nonprofit newsrooms. Sheila Kaplan is a fellow at Harvard University’s Edmond J. Safra Center for Ethics.

More from Open Channel:

Follow Open Channel from NBCNews.com on Twitter and Facebook