Maui Discussion

Maui’s Cane Burning – How Dangerous Is It?

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Editor’s Note: At the request of A&B/HC&S, the following corrections were made to this article. 1) burning coincides with harvesting, not six months prior as originally written. 2) A&B does not own Kuau Bay View.

HC&S submitted a response to this story, and it is posted here: HC&S Responds to ‘Cane Burning Dangerous?’ Article

Allison Sickle is an environmental journalist on special assignment for Maui Now.

By Allison Sickle

Sugar cane burn_march 20_2012-black-plume

March 20, 2012 cane burn over Maui. Photo by Allison Sickle.

While winter on the mainland is wrapping up, residents on Maui are gearing up for a different type of snow.


Referred to as “Maui snow,” this black ash falls from the sky during sugar cane field burns, blanketing cars and buildings. It has provoked decades of controversy on the island, sometimes leading to violent threats against people opposed to this agricultural practice, and it continues to keep some residents locked in their houses with the air purifier running and the windows and doors sealed.

But the Hawaii State Department of Health disregards potential health effects from these fires and lacks regulations to prohibit burning irrigation piping that releases hazardous pollutants. And although the EPA (Environmental Protection Agency) says no air toxins are coming from sugar cane fields, researchers recently identified 10 compounds emitted when burning cane trash that the agency is required to regulate.

HC&S – Hawaii’s Last Working Sugar Plantation

Acquired in the late 1800s by Alexander and Baldwin, Inc. – now a multi-billion dollar global corporation engaged in agribusiness, real estate and transportation, Hawaiian Commercial and Sugar Company currently grows about 35,500 acres of two-year sugar cane on the island. After roughly 18 months of growth, the fields are dried out and ripened prior to harvest, generally over a four to six month period. The company burns this crop in 60 to 100 acre increments during the harvest to make it cheaper to transport and easier to process.

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During these open-air fires, which usually begin in March and last until November each year, leaves from the ground, bottom, midpoint and often the top of the cane are burned. This year, HC&S plans to torch around 400 acres a week, emitting particulate matter and other substances into the air to harvest about 15,400 acres of cane total.

When asked his response to claims that sugar cane field burning is causing respiratory issues, itchy eyes and dizziness, Deputy Director Gary Gill from the Department of Health’s Environmental Health Administration says he cannot respond to “general rumors” or “concerns,” but if someone is experiencing impacts, they should check with their doctors, as his staff are not private physicians.

“We regulate under the laws and rules to protect public health,” says Gill. “But certainly people, especially if they haven’t grown up with the tradition of agricultural burning in what used to be rural Maui – some people have a very negative reaction to it.”

Asthma affects over 106,000 people in Hawaii with children making up a third of the total. But the human health impacts of exposure to plumes from sugar cane fields on Maui are widely understudied. And research published on this matter as it relates to Hawaii is outdated, usually excludes residents with prior health conditions, and has mainly focused on impacts to plantation workers.

However, more recent studies have concluded that exposure to certain concentrations of particulate matter, which is emitted when burning sugar cane, causes a variety of respiratory and cardiovascular impacts like exacerbated asthma and nonfatal heart attacks. Research in the US has also concluded that short-term exposure to particulate matter with a diameter of 2.5 micrometers or smaller, which is less than a quarter the width of a human hair, increases the risk of hospitalization for cardiovascular and respiratory diseases. And a study in Brazil has documented a two to three-fold increase in respiratory hospitalization among children and elderly during periods of pre-harvest sugar cane burns.


“There is an awareness here that there are those in our community who are affected, and we’re certainly trying to compile data on that and days and times and the real impacts so that we have a better picture of what these impacts are and not just refer somebody to our public health officer Dr. Pang or to the Clean Air Branch,” says Maui County Environmental Coordinator Rob Parsons.

Parsons said that many residents from the central valley called and emailed him last October during cane burns complaining about conditions and that some parents kept their children out of school in their room with the air purifier on. Fatigue, migraines, dizziness and respiratory issues are some of the conditions residents say they suffer from as a result of exposure to cane smoke.

Conditions in Paia Cause Health Concerns

“Last year in Paia, they burned the sugar cane on days when it caused the smoke to literally choke us so that you could not see more than three houses down the road,” says Karen Chun, a 62-year-old Paia resident who lives next to a sugar cane field in Kuau Bay View. “It was so thick in your house it was like it was on fire because it was so filled with smoke.”

After experiencing several burns of this magnitude, Chun, a non-smoker and former athlete, developed a reoccurring cough. Chun visited her family practitioner, Dr. Errol Buntuyan, about a month later who gave her a lung capacity test revealing her lungs were operating at two-thirds of their capacity. She says he diagnosed her with reactive airway disease, a breathing problem that appears as wheezing or whistling in the airways that could be classified as asthma if chronic.

“I still have an inhaler,” says Chun. “I still have to use it, but at least, I’m not coughing every 10 minutes – but I’ve been permanently damaged.”

Dr. Buntuyan, who has been practicing medicine on Maui for over four years, says during the cane burning period, more patients – including smokers and non-smokers of all ages with and without prior health conditions – visit his office with respiratory symptoms and that he treats about 100 to 200 people annually with conditions related to this harvesting practice, usually patients with reactive airway disease.

“It [reactive airway disease] could be caused by a number of things – viral, bacterial infection, allergies, smoke or tobacco, namely,” says Dr. Buntuyan. “But then, in our environment in Maui, I’ve been noticing it tends to flare up after they’ve done burns or, in our environment, if the vog has been in the air for a long time.”

The Department of Health’s Clean Air Branch regulates sugar cane field burning through an agricultural burn permit. This permit contains conditions like banning fires on no-burn days and prohibiting the burning of certain materials including tires.

When determining no-burn days, the Clean Air Branch does not rely on air monitors to measure concentrations of pollutants in the air like sulfur dioxide coming from the volcano on the Big Island. Officials usually call no-burn days by noon making a visual determination the haze and examining wind conditions, like speed and direction, to determine if the haze will likely lift, according to Lisa Young, section supervisor for monitoring with the department. But since HC&S often burns early in the morning, fires may occur before the Clean Air Branch decides whether or not to restrict burning.

Blake Shiigi is the one inspector from the Clean Air Branch for agricultural burning on Maui. Although he does not visit all sites before fires begin, he does

investigate complaints. However, Young says because HC&S has says they do not burn irrigation piping, the agency has never examined if the company is burning this material.

PVCs Emit “Likely” Cancer-Causing Toxins when Burned

HC&S uses underground poly vinylchloride, or PVC, pipes to transport water across the plantation to polyethylene drip tape that delivers water to the crop’s roots. The company burns most of the polyethylene drip tape during pre-harvest fires but avoids burning PVC pipes by pushing the cane away from this material and wetting it down before hand, according to HC&S General Manager Rick Volner.

Sugar cane burn_March 20_2012-black-white-plume

3/20/2012 cane burn. Photo by Allison Sickle.

Poly vinylchloride and polyethylene are plastics that emit toxins when burned. Dioxins, a class of chemicals the EPA classifies as a “likely” carcinogen, are released when PVC is burned. Exposure to some dioxins can cause a variety of impacts like suppression of the immune system, reproductive disorders and endocrine disruption.

Associate Director Kerry Drake of EPA’s Region 9 Air Division, which covers Hawaii, says the EPA would be concerned if PVC is being burned, but the agency would not be concerned if polyethylene was being burned as long as there is a burn management plan to keep emissions away from citizens.

But according to Acting Manager Nolan Hirai of the Clean Air Branch, the Hawaii Department of Health has no specific regulations to govern the burning of these pipes.

In addition to regulating agricultural burning through a permit, the Clean Air Branch also monitors particles emitted from cane burns in order to comply with ambient air quality standards set by the EPA. Under the authority of the Clean Air Act, the EPA established national ambient air standards for six criteria pollutants, including particulate matter.

The EPA classifies particulate matter by size with fine particles having a diameter of 2.5 micrometers or smaller and course particles with a diameter of greater than 2.5 but less than or equal to 10 micrometers. The EPA’s national ambient air quality standards for daily levels of particulate matter are 35 micrograms per cubic meter for fine particles and 150 microgram per cubic meter for course particles.

Maui Has One Air Monitor for Entire Island

Maui has one air monitor at Hale Piilani Park in Kihei that detects only fine particulate matter for the entire island. Although residents do not breathe averages, federal regulations allow states to average levels of particulate matter detected over a 24-hour period to determine whether they are in compliance with allowable levels. The Clean Air Branch documents daily levels and report the results to the EPA quarterly.

According to Drake, particulate readings from the air monitor at Hale Piilani Park have exceeded the daily standards twice in the past 10 years. But regulators attributed the exceedances to agricultural tilling and construction and demolition, and since the exceedances were the only occurrences in those years, neither had violated the health-based standard.

The Clean Air Act also required the EPA to identify categories of sources emitting any of the 188 toxins included on the agency’s hazardous air pollutants list and establish emission standards for each category. Drake says from the studies the EPA has seen, there are no air toxins coming from sugar cane fields. But in 2010, researchers from the University of Florida conducted a study sponsored by the Palm Beach County Health Department to determine emission factors for various toxins coming from pre-harvest sugar cane burning and identified contaminants on the EPA’s air pollutant list.

“The reason why EPA doesn’t have any regulations on other chemicals is because they simply don’t have enough data to do that yet,” says Chang-Yu Wu, one of the leading researchers and a professor in Environmental Engineering Sciences at University of Florida.

According to a list Wu provided of toxins identified in the study, researchers detected 10 hazardous air pollutants the EPA is required to regulate – including naphthalene, formaldehyde, benzene and styrene, to name a few. Certain doses of these toxins can cause impacts ranging from drowsiness and headaches to neurological and liver damage. However, Wu says he is uncertain if the pollutants they detected are health hazards because they determined emission rates while the EPA bases its standards on concentrations.

Mountains and Wind Create the “Maui Vortex”

Environmental conditions can impact concentrations of pollutants in the air. For example, strong winds may disperse toxins lowering concentrations while a stable atmosphere could cause pollutants to accumulate on the ground level and potentially be hazardous.

Yi-Leng Chen, a metrology professor in the School of Ocean and Earth Sciences and Technology at University of Hawaii, conducted a high resolution modeling study in 2005 to examine air flow for Maui. His research revealed that the trade winds interact with the volcanic mountains creating a closed circulation system called the “Maui Vortex” over the central valley that traps pollutants.

“I think the implication is that sugar cane burning will not be carried away by trade,” says Chen. “That’s pretty obvious because there is no trade over the central valley because the trade is being blocked completely by the high mountains.”

Some residents doubt federal and state regulators’ ability to ensure clean air and protect human health amidst agricultural burning. And according to Parsons, Mayor Arakawa’s office has even proposed that the charter commission, a committee consisting of 11 members he appointed to review governmental operations, add language to the county charter that would address more environmental protection and sustainability.

“They can tell us what they want, but at the end of the day, I don’t know how healthy it is if you are breathing something that gives you bad headaches,” says Scott Stephens, a resident of North Kihei that has lived on Maui for eight years.

But other people, like Francis Michael Patrick Lydon, a 10-year resident of Ma’alaea who lives in a condo along the beach across the street from a sugar cane field, say residents that moved to Maui after this harvesting practice began have to expect results from burning. Lydon closes his sliding door to keep the smoke out, noting that the burning is a “pain in the neck.”

However, Lydon and his wife suffer no health effects. He says he prefers sugar cane over housing, which he foresees as a likely alternative for the land, and that he is “totally” in favor of the field burning because the industry provides an economic base for Maui.

“No way would I want politicians or anybody stopping their business,” says Lydon. “They have the right to run their business, and I don’t think we have the right to shut them down.”

Cane Burning Supporters “Play Hardball”

In the past, residents who have criticized biomass burning citing health effects have suffered retribution from other community members. Chun wrote a letter to the editor of Maui News condemning HC&S for burning cane after she got sick last year. According to Chun, after it was published, some of company’s employees threatened her and that representatives of the International Longshore and Warehouse Union, a labor union with about 21,000 members in the state, told her they would have the police arrest her for trespassing if she visited their meeting hall.

Another resident from Upcountry, who spoke on the condition of anonymity due to safety concerns, says during the 25 years that she advocated against this harvesting practice, her brake lines were cut and on five or six different occasions, strangers on the street and in businesses slid their hand across their throats to incite terror.

“I want people to know when they write their letters to the editors be prepared,” she said. “They play hardball, and I’m not saying that lightly.”

HC&S Tries Alternatives

Sugar cane burn_March 20-2012 in brush

Photo by Allison Sickle.

HC&S currently employs about 800 workers on Maui. Last year, the company generated 6% of Maui Electric Company’s total energy, harvested 15,063 acres of sugar cane, and produced 182,800 and 51,106 tons of raw sugar and molasses, respectively. These labors, in addition to other operations of A&B’s agricultural sector, reaped an operating profit of $22.2 million for 2011.

According to Volner, over the last two decades, the company has invested millions of dollars into pursuing alternatives to pre-harvest sugar cane burning, including: a three-year study into mechanical harvesting of a one-year cane crop, an unsuccessful attempt to add a valuable co-product by investing in a fiberboard plant, and ongoing exploration of ethanol production from cane trash and other biomass.

“Until proven technology can be developed to cost-effectively produce energy from the leaves, large-scale harvesting of unburned cane in Hawaii is not viable, and maintaining the ability to burn is still an important factor in the survival of the company and the jobs it provides to Maui residents,” he says.

However, Parsons says robust economic models may exist that would not have as many negative impacts on the environment as the sugar cane plantation. He says he hopes the community can use dialogue and forums to propose sustainable agricultural models that do not harm human health.

“There’s probably a number of models that could be discussed and evaluated that would provide just as much income if not more, that would provide just as many jobs if not more, and that would do so much less polluting and health impacting ways,” says Parsons.

Video above features footage of cane smoke from a residential neighborhood in Kuau in August, 2011.


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