Measure air pollution in your home or backyard with a DustDuino

This week, the World Health Organization (WHO) took a major step by announcing that air pollution is carcinogenic to humans.

WHO also announced they are considering particulate matter, a major component of indoor and outdoor air pollution, as carcinogenic to humans as well.

International Agency for Research on Cancer announced today: outdoor #airpollution is leading environmental cause of #cancer deaths
— WHO (@WHO) October 17, 2013

The International Agency for Research on Cancer (IARC), a special unit inside WHO tasked with promoting international collaborations on cancer research, reached that conclusion after reviewing more than 1000 scientific papers on the carcinogenicity of air pollutants.

Air pollution and particulate matter will be included in IARC's Monograph, which is an encyclopedia of known carcinogens. Particulate matter will be classified as a Group 1 carcinogen, along with tobacco smoke and asbestos.

In an IARC press release [1], the Deputy Head of the Monographs Programme, Dr. Dana Loomis, said that the group's goal was to "evaluate the air everyone breathes rather than focus on specific air pollutants."

"The results from the reviewed studies point in the same direction: the risk of developing lung cancer is significantly increased in people exposed to air pollution," he said.

This finding elevates the urgency to clean up the air, both outdoors and indoors. But how does one find out the condition of the air in the first place? How healthy is your air?

Understanding air pollution with a simple dust sensor

Outdoor air pollution, in the most extreme cases, can be immediately identified even without any special training. It casts a haze over cities, collects on streets and buildings, and provides dramatic fodder for the news. Even when the air pollution isn't actually visible, we can smell when something isn't quite right.

I previously wrote about how difficult it can be to obtain basic environmental data, and how government budget cuts are threatening air monitoring networks in several states. It now appears that other countries are making hard decisions about which monitors to keep, and which monitors to shut down. The Guardian reported recently that up to 600 air quality monitors, including monitors for nitrogen dioxide and particulate matter (PM), could be shut down across the United Kingdom.

Yet for all the attention the media pays to outdoor pollution, people spend only about 1 to 2 hours outdoors (and that's only in the pleasant summer months) according to one University of Newcastle study. According to the EPA, we spend about 90 percent of our time indoors. We spend the vast majority of our time indoors, so it makes sense monitor pollution in the home.

Indoor Air Pollution (IAP) is an especially big problem in developing countries, where 60 to 90 percent of households still rely on coal and wood for heat and food preparation. About 36 percent of acute lower respiratory infections and about 22 percent of chronic obstructive pulmonary disease (COPD) in the developing world are caused by IAP (pdf). In one study of women in China, researchers found that a 10 μg/m³ (microgram per cubic meter) increase in PM₁ (ultrafine particles smaller than one micrometer) was associated with 45 percent increased risk of lung cancer.

IAP isn't just a concern in developing and BRIC nations, though. Similar problems exist for the rural poor in the US and Canada, where indoor pollution exceeds the World Health Organization air quality guidelines in up to 80% of homes. As in BRIC nations, these homes rely greatly on burning organic fuels.

Air quality at home can be an issue even for homes that don't burn wood or coal. Indoor air pollution can come from "molds, bacteria, viruses, pollen, animal dander and particles from dust mites and cockroaches," according to the American Lung Association.

Indoor air pollution ranks among the top five environmental risks to public health, the EPA says. Indoor pollution levels may be two to five, and sometimes 100, times higher than outdoor pollution.

All that makes the indoors a great place to put a dust sensor.

A massive, toxic tire fire, and how citizen sensor journalism could have informed a community in crisis.

A fire at a tire disposal plant in the small town of Hoopeston, Ill., polluted the skies for hours. Photo by @JonathonLinares.

At 5:30 am on Wedneday, June 19, a spark generated by static electricity at J&R Used Tire Service started a fire that would black out the sky for miles around the small town of Hoopeston, Ill.

Initial reports from fire crews suggested the fire could burn for days. By the time it was extinguished the next day, more than 100 firefighters from two states had come to snuff the tire fire, about 500 homes had been evacuated, and rail service through the town was shut down.

According to the Champaign-Urbana NPR affiliate WILL, state environmental officials requested that the state's attorney general to issue a court order to stop the business until it's determined how the fire started, how safe the business is, and what kind of environmental impact this fire had on the community.

The Illinois Environmental Protection Agency seems primarily concerned with the air and water at the moment. A tremendous amount of water was used to extinguish the blaze, and that water has been contaminated with the byproducts of burning tires.

Obviously, there's a great deal of burning material that was sent into the air. IEPA has been monitoring the air in Hoopeston (pop. 5,321), but that data hasn't been made public on any sort of accessible website.

Step-by-step guide to programming the RN-XV WiFi module for Arduino

The Arduino prototyping standard has been around for about 6 years now, and has proven to be immensely useful for sensing devices. It's the heart of the DustDuino and many other sensor nodes.

But for all the flexibility that the Arduino provides for collecting data about the environment, there still isn't a reasonably-priced, reliable shield to send data via WiFi.

The official Arduino WiFi shield, while well-supported, costs around $85. That's a pretty high price to connect a $4.50 chip to a network. Cheaper options such as the WiFly shield do exist, but some of the libraries supporting these devices are difficult to decipher or unstable, if they exist at all.

I spent a long time myself looking for a cheap, effective WiFi solution for the Arduino platform, and I've been very pleased with the $35 RN-XV module.

DustDuino: A plan to crowdsource environmental reporting with low-cost dust sensors

A before and after photo of Shanghai inundated with smog, by Flickr's morgennebel.

There's some good news in the air. Or, well, about the air.

Last month, the American Lung Association released its 2013 report on the quality of the nation's air. The Lung Association's "State of the Air" report shows the country's air is continuing to improve.

The Lung Association attributes healthier air as a "direct result of emissions reductions from the transition to cleaner diesel fuels and engines and coal-fired power plants, especially in the eastern United States."

That much is good. But there's much room for improvement.

According to the report, "Of the 25 cities with the worst problem with spikes in particle pollution, fourteen had more days or worse problems in 2009-2011 than in the previous report." Six cities included in the report had their worst year ever (over the 14 years the report has been made) for short-term spikes in particulates.

Chicago, home to some of the dirtiest coal-fired power plants in the nation, continued to flunk both daily and annual levels of particulate pollution. This was where I did my own environmental investigation on how the Fisk coal-fired power plant threatened the health of the Pilsen neighborhood (see: "Battle in the Barrio").

The Fisk station dumped 755 tons of particulates into the air on an annual basis, according to a pollution report from the Environmental Protection Agency. The Clean Air Task Force found that the plant contributed to 15 deaths and 23 heart attacks annually, a figure based on EPA data.

The residents of Pilsen eventually won their battle, and the Fisk station was closed. EPA tests after the plant closure showed the particulate and radiation levels had returned to city-wide norms. Interestingly, one of the EPA air quality monitors was mounted in a baby stroller to measure levels around the perimeter of the plant.

Pilsen didn't have air quality monitors to begin with, though. Its residents had to lobby the Illinois EPA before the state placed an air monitor atop an elementary school in the neighborhood. The readings from the monitor led the IEPA to declare Pilsen a "nonattainment" zone for lead, a particulate which impairs the IQ, learning capabilities, and memory of children.