Scientists find evidence of human air pollution dating back to 1500s

The Adnes is the longest continental mountain range in the world stretching from Venezuela to Argentina. (Michael McDonough/Flickr)
The Adnes is the longest continental mountain range in the world stretching from Venezuela to Argentina. (Michael McDonough/Flickr)

Nick Fetty | February 10, 2015

Researchers have recently discovered evidence of air pollution believed to be from 16th century silver production in Bolivia.

The research team was led by Ohio State University professor Paolo Gabrielli with OSU’s Byrd Polar and Climate Research Center. The researchers discovered an imprint of smog high in metal content in an Andean ice cap in Peru but the source of the pollution is likely hundreds of miles east in present-day Bolivia.

The air pollution was believed to come from to come from silver refineries in the mountain town of Potosí. Prior to Spanish colonization, the Inca people mined silver in the area and at one point Potosí was the silver mining capital of the world. However with Spanish colonization came more efficient methods for mining silver which in turn led to greater amounts of air pollution. Much of the pollution from the silver mines consisted of lead, arsenic, and other materials and was believed to have occurred during between the 16th and 18th centuries.

The article was published in Proceedings in the National Academy of Sciences. The authors conclude: “This anthropogenic pollution of the South American atmosphere precedes the commencement of the Industrial Revolution by ∼240 y(ears).” Some scientists say that human-caused air pollution – “though agriculture, mining, fossil fuel production and other industrial activities” – has put us in a period known as Anthropocene. However scientists debate about when exactly this period began and Gabrielli’s recent findings would suggest that the period started earlier than previously thought.

The research was funded by the National Science Foundation (NSF) Paleoclimate.

Climate change denial is a turnoff to voters, poll finds

The United States capitol (Snapper CR29 / Flickr)
The United States Capitol (Snapper CR29 / Flickr)

Voters are overwhelmingly less likely to vote for a candidate who calls climate change a “hoax,” according to a recent poll.

The survey, conducted by The New York Times, Stanford University and research group Resources for the Future, gathered opinions from voters related to climate change and politics. It found that an overwhelming majority of voters believe global warming will pose serious problems for the country if nothing is done to curb it, and that Americans are more likely to vote for a candidate who takes climate change seriously. In addition, 78% of respondents, including 60% of self-identified Republicans, agreed that the federal government should act to limit the amount of greenhouse gases emitted by U.S. businesses.

Of note were the responses provided by Republicans, which indicate a shift away from outright climate science denial. While 48% of Republicans were more likely to vote for a candidate who said, “I believe that global warming has been happening for the past 100 years, mainly because we have been burning fossil fuels and putting out greenhouse gasses,” the same number, 48%, were less likely to vote for a candidate who said, “The science on global warming is a hoax and is an attempt to perpetrate a fraud on the American people.” However, politicians who use the “I’m not a scientist” line, an attempt at a non-answer, also scored favorably among Republicans, with 37% saying they would be more likely to vote for a candidate who used similar language regarding climate change.

This comes after a U.S. Senate resolution on climate science passed 98-1, stating that “climate change is real and not a hoax.” Challenges persist, however, in convincing Senate members that human activity causes climate change, with members split about evenly at 50-49. This led a panel of Iowa scientists to publish an editorial in The Des Moines Register further clarifying the general consensus among climate scientists: “We know humans, by adding greenhouse gases to the atmosphere, have altered the climate.”

See the full poll results here: Global Warming: What Should Be Done?

EPA faces lawsuits for animal confinement air pollution

A pig at St Werburghs City Farm in the United Kingdom. (Ed Mitchell/Flickr)
A pig at St Werburghs City Farm in the United Kingdom. (Ed Mitchell/Flickr)

Nick Fetty | January 29, 2015

Two lawsuits were brought against the U.S. Environmental Protection Agency on Wednesday alleging that the group isn’t doing enough to prevent air pollution caused by large animal confinement facilities.

The lawsuits filed in U.S. District Court in Washington D.C. were brought about by a coalition of eight groups including the  Environmental Integrity Project, the Humane Society of the United States, Center for Food Safety, Sierra Club, Friends of the Earth, Clean Wisconsin, Iowa Citizens for Community Improvement, and the Association of Irritated Residents (represented by the Center on Race, Poverty & the Environment). The coalition says that the lack of regulation by the EPA has allowed factory farms to pollute the air and threaten public health.

Specifically the lawsuits pertain to petitions filed in 2009 and 2011. The 2009 petition was filed by the Humane Society of the United States and called for concentrated animal feeding lots – or CAFOs – to be categorized as a source of pollution under the Clean Air Act and for new standards to be enforced on new and existing CAFOs. The Environmental Integrity Project filed the 2011 petition and sought health-based standards for ammonia emissions. The lawsuit asks for the EPA to respond to these petitions within 90 days.

A spokesman for the National Cattlemen’s Beef Association said that beef producers have made efforts to reduce pollution without government intervention and between 2005 and 2011 were able cut emissions in water by 10 percent and greenhouse gas production by 2 percent. However, Iowa Pork Producers and an Iowa State University professor say that the link connecting CAFOs to health hazards is inconclusive.

Tulane researchers studying mockingbird songs to gauge effects of lead pollution


A mockingbird perched on a branch in Mexico. (Dennis Jarvis/Flickr)
A mockingbird perched on a branch in Mexico. (Dennis Jarvis/Flickr)

Nick Fetty | January 20, 2015

Researchers at Tulane University in New Orleans are studying songs sung by mockingbirds to determine the effects of lead levels in the environment.

Dr. Renata Ribeiro – an adjunct professor in the Department of Ecology and Evolutionary Biology – has been studying the Northern Mockingbird. As the name implies, these birds often imitate the songs sang by other birds as well as car alarms, emergency sirens, and other sounds. The singing ability of male mockingbirds is crucial to finding a mate.

Ribeiro and other researchers are studying how the Northern Mockingbird and its songs are affected by lead pollution which contaminates much of the soil in The Big Easy. A 2011 study by Tulane University found that nearly two-thirds of New Orleans homes and yards contain “dangerous” levels of lead. Researchers attributed the high levels of lead to the demolition and renovation of houses after Hurricane Katrina as well as the large number of homes constructed before lead was banned from house paint in 1978. The Louisiana Department of Environmental Quality has also reported air quality concerns in the state’s biggest city. Exposure to unsafe levels of lead and other environmental pollution has been tied to learning disabilities in children as well as neurological damage in animals.

Ribeiro’s efforts are part of a one-year study sponsored by the Morris Animal Foundation. She and her team will return to the field next month as the birds become more active again in preparation for mating season.

On the Radio: Iowa ahead of new smog standards

The Des Moines skyline at dusk (Jason Mrachina / Flickr)
The Des Moines skyline at dusk (Jason Mrachina / Flickr)

This week’s On the Radio segment looks at early assessments of Iowa’s ozone emissions, which suggest that the state is one step ahead of upcoming new emission standards. Listen to the audio below, or continue reading for the transcript.

Transcript: Ozone standards

Iowa is one step ahead of new national ozone emission standards.

This is the Iowa Environmental Focus.

In November, the U.S. Environmental Protection Agency released a draft proposal to drastically reduce ozone emissions from power plants and other sources by 2025. All 99 of Iowa’s counties are set to meet the new standards, according to data collected by the Iowa Department of Natural Resources.

The EPA’s Clean Air Scientific Advisory Committee earlier this year recommended ozone levels be reduced to between 65 and 70 parts per billion, down from the current practice of 75 parts per billion.

Iowa already meets the EPA standards, with monitoring stations showing average ozone levels between 61 and 69 parts per billion. The Iowa DNR supplies data to the EPA’s Air Quality Index, which provides air quality conditions in real time.

For a link to the Air Quality Index, visit

From the UI Center for Global and Regional Environmental Research, I’m Jerry Schnoor.

Iowa Environmental Focus: Best of 2014


As 2014 comes to a close, it’s time to look at some of the Iowa Environmental Focus’s most shared and talked-about blog posts of the year. These are the posts that helped spur conversation on important environmental topics in Iowa and around the world. Thanks for your support, and Happy New Year!

Climate and health experts discuss effects of climate change on Iowans – The Iowa Environmental Focus visited the 2014 Iowa Climate Science Educators Forum in October, to learn how climate change is affecting Iowa’s air quality, water quality and public health.

Large solar energy project coming to Mitchell county in northern Iowa – This project could be one of the largest in the state, with 1,200 solar panels.

Iowa Climate Statement 2014: Impacts on the Health of Iowans – The 4th annual Iowa Climate Statement was released in October, highlighting the health effects of climate change on Iowans. The blog  took photos and video of the event, which took place at the Des Moines statehouse.

University of Iowa research examines health effects of frac sand mining – A look into the research on the health effects of frac sand mining, or fracking, in Iowa.

MIT engineers discover way to create efficient solar panels using lead recycled from car batteries – The future of solar power could lie in old car batteries, according to engineers at MIT.

Grinnell College blown off course on campus wind energy project  – The Iowa Environmental Focus covered a setback at Grinnell College, where plans for a 5.1-megawatt wind farm were halted in October.

Proposed oil pipeline would run through 17 Iowa counties – An 1,100-mile oil pipeline was proposed to run from Lyon County in the northwest corner of Iowa to Lee County in the southeast.

Ottumwa meat plant is Iowa’s top waterway polluter – A report that showed, among other concerns, that one Iowa meat plant dumped three million pounds of chemicals into the Lower Des Moines River in 2012.

Iowa’s Allamakee county looks to implement nation’s strictest fracking ordinance – In June, the Allamakee County (Iowa) Board of Supervisors voted 3-0 to approve what looks to be “the most strict frac sand mining ordinance in the nation.”

Hemp advocates announce 6th Annual Hemp History Week – This event, taking place in 2015, aims to bring attention to hemp as an environmentally sustainable crop with both nutritional and medical uses.

Natural Christmas trees could be a green alternative this holiday season

A family at a Christmas tree farm (Mass Office of Travel / Flickr)
A family at a local Christmas tree farm (Mass Office of Travel / Flickr)

With the holiday season in full swing, natural Christmas trees grown in Iowa may provide a greener way to deck the halls.

Each year, around 100 Iowa farmers grow various pines, spruces and firs for holiday decor on more than 1,500 acres of farmland, much of which is unsuitable for other crops. Unlike artificial Christmas trees made of plastic and synthetic materials, natural Christmas trees produce minimal waste, can be recycled as mulch, and absorb carbon dioxide while producing oxygen during their lifetime, usually 6 to 12 years before harvest. While artificial trees remain in landfills for centuries after use, natural Christmas trees can be reused as decoration or sunk into fishing ponds to make refuges for fish. They can also be used as sand and soil erosion barriers near river beds.

Iowa tree farmers saw a rebound in tree growth this year, after drought in 2012 killed off crops across the state. Growers must constantly monitor their trees for insects and leaning to ensure proper balance and form. Iowans harvest about 39,500 Christmas trees each year, mostly by selecting and cutting down the trees themselves at the farm. For a list of Christmas tree growers in your area, visit the Iowa Christmas Trees website. City utilities often provide information and services about tree pickup and recycling.