A new study by non-profit Environment and Human Health, Inc, “LEED Certification: Where Energy Efficiency Collides with Human Health,” pinpoints weaknesses in the certification, and so recommends that LEED certification be measured separately in different categories.

According to the study, the way LEED certification measures adverse health impacts of building materials gives a false impression of the safety of “environmentally friendly” buildings. A building achieves LEED status based on an aggregate score, with some measurements, such as energy efficiency, weighing more towards the final score than others, like air quality.

So a building can achieve the highest LEED certification – Platinum, even if it makes no improvements in indoor air quality, the study states.

“Although the primary stated purposes of the Green Building Council are to promote both energy efficiency and human health, even the Council’s most prestigious Platinum award does little to ensure that hazardous chemicals are kept out of the certified buildings,” said John Wargo, a professor of Risk Analysis and Environmental Policy at Yale University, and the study’s lead author.

The EHHI study actually finds that more energy efficient buildings may actually increase exposure to toxic chemicals since energy conservation often requires reducing air exchange between indoors and outdoors. Very few of the tens of thousands of chemicals that may be found in a building have been federally tested for toxicity, the study said.

Rather than issuing awards of “platinum,” “gold” and so on, the Green Building Council, which administers LEED certification, should require performance within each category (health, energy, sites, neighborhoods, etc.) on a 0-100 scale, according to the study’s recommendations.

The study also recommends that more health scientists and physicians with formal medical, epidemiological and toxicological training be included on the GBC’s board of directors. Currently only one director out of 25 has such a training.

How important do you think it is for LEED to consider indoor hazardous chemicals? Should that be part of the green building code?