Quantcast

Low Doses Matter More than You Think

Center for Health, Environment & Justice

By Stephen Lester

How often have you been told that the levels of a particular chemical found in the air, soil or water are very low and thus not significant, or that the risks are so low that there's no cause for alarm?

This is what the U.S. Environmental Protection Agency (EPA) said about dioxin about a month ago when it released its non-cancer report. Now, a new scientific report is helping make the case that most people living in a contaminated community have known for years—low dose effects matter.

A group of scientists led by Laura Vandenberg at Tufts University reviewed hundreds of published scientific papers—many on endocrine disruptors—and found dozens of examples of low dose effects. These papers included a wide range of chemicals including many found in the environment, our food and many consumer products such as plastics, pesticides and cosmetics. The researchers found “overwhelming evidence that these hormone altering chemicals have effects at low doses and that these effects are often completely different than effects at high levels.” Low doses are defined as levels occurring in the range of typical human exposure.

This is a remarkable paper. It says and supports what community leaders having been saying for years—low dose exposures are damaging peoples' health and the way scientists evaluate health risks using risk assessment no longer work. One of the key conclusions in the paper is that “the effects of low doses cannot be predicted by the effects observed at high doses.” This paper needs to be read by every regulating agency at the state and federal level because it opens the door to a new way of thinking about heath risks. No longer is it enough or even good science to evaluate health risks using traditional dose response thinking that accepts effects at high doses, but not at low doses.

As noted in an earlier blog, Linda Birnbaum, director of the National Institute for Environmental Health Sciences, described this traditional approach to evaluating health risks as “antiquated” and claimed that it needs to be replaced by a “better understanding of the actual characteristics of modern environmental chemicals.” In a recent editorial, Birnbaum said, "It is time to start the conversation between environmental health scientists, toxicologists and risk assessors to determine how our understanding of low dose effects and non-monotonic dose responses influence the way risk assessments are performed for chemicals with endocrine disrupting activities."

Birnbaum is right. We need to begin rethinking how we evaluate health risks from low dose exposures to toxic chemicals. For a copy of the Vandenberg paper, click here.

For more information, click here.

EcoWatch Daily Newsletter

Scanning electron micrograph of Yersinia pestis, which causes bubonic plague, on proventricular spines of a Xenopsylla cheopis flea. NIAID / Flickr / CC BY 2.0

A middle-aged married couple in China was diagnosed with pneumonic plague, a highly infectious disease similar to bubonic plague, which ravaged Europe in the middle ages, as CNN reported.

Read More Show Less
Milk made from almonds, oats and coconut are among the healthiest alternatives to cow's milk. triocean / iStock / Getty Images Plus

Dairy aisles have exploded with milk and milk alternative options over the past few years, and choosing the healthiest milk isn't just about the fat content.

Whether you're looking beyond cow's milk for health reasons or dietary preferences or simply want to experiment with different options, you may wonder which type of milk is healthiest for you.

Read More Show Less
Sponsored
Greta Thunberg stands aboard the catamaran La Vagabonde as she sets sail to Europe in Hampton, Virginia, on Nov. 13. NICHOLAS KAMM / AFP via Getty Images

Greta Thunberg, the teenage climate activist whose weekly school strikes have spurred global demonstrations, has cut short her tour of the Americas and set sail for Europe to attend COP25 in Madrid next month, as The New York Times reported.

Read More Show Less
The Lake Delhi Dam in Iowa failed in 2010. VCU Capital News Service / Josh deBerge / FEMA

At least 1,688 dams across the U.S. are in such a hazardous condition that, if they fail, could force life-threatening floods on nearby homes, businesses, infrastructure or entire communities, according to an in-depth analysis of public records conducted by the the Associated Press.

Read More Show Less

By Sabrina Kessler

Far-reaching allegations about how a climate-sinning American multinational could shamelessly lie to the public about its wrongdoing mobilized a small group of New York students on a cold November morning. They stood in front of New York's Supreme Court last week to follow the unprecedented lawsuit against ExxonMobil.

Read More Show Less
Sponsored

By Alex Robinson

Leah Garcés used to hate poultry farmers.

The animal rights activist, who opposes factory farming, had an adversarial relationship with chicken farmers until around five years ago, when she sat down to listen to one. She met a poultry farmer called Craig Watts in rural North Carolina and learned that the problems stemming from factory farming extended beyond animal cruelty.

Read More Show Less
People navigate snow-covered sidewalks in the Humboldt Park neighborhood on Nov. 11 in Chicago. Scott Olson / Getty Images

Temperatures plunged rapidly across the U.S. this week and around 70 percent of the population is expected to experience temperatures around freezing Wednesday.

Read More Show Less
A general view of the flooded St. Mark's Square after an exceptional overnight "Alta Acqua" high tide water level, on Nov. 13 in Venice. MARCO BERTORELLO / AFP / Getty Images

Two people have died as Venice has been inundated by the worst flooding it has seen in more than 50 years, The Guardian reported Wednesday.

Read More Show Less