Methyl bromide, a neurotoxin that carves holes in the ozone layer, is up for permitting at the Port of Wilmington

Methyl bromide, a neurotoxin that carves holes in the ozone layer, is up for permitting at the Port of Wilmington

- in Environment, News, Top Story
Logs at the Port of Wilmington, off River Road (Photo: Lisa Sorg)

The Port of Wilmington is a 284-acre maze of steel, cable and concrete where ships as long as three football fields maneuver through the channel.

Cranes hoist shipping containers and stack them like Lego blocks. Inbound or outbound, they are crammed with goods — grains and wood, chemicals and clothes — and are headed for the railroad, the highway, or 26 miles down the river to the open sea.

Some of those containers hold logs cut from North Carolina forests. But before the logs can be shipped to China, their most common destination, insects hiding in the bark must be killed.

One method of killing the pests is methyl bromide, which in sufficient quantities, can also kill people.

The NC Department of Environmental Quality is holding public hearings next week on two draft permits for the use of methyl bromide, a neurotoxin and ozone-depleting chemical that has been all but banned under an international agreement, the Montreal Protocol. Roughly 150 countries have agreed to freeze production levels of methyl bromide.

However, methyl bromide is still legal in some instances; the EPA has granted a “critical exemption” for the chemical to fumigate logs for export.

The use of methyl bromide is not new in North Carolina, but emissions standards are. In 2018, DEQ proposed adding the chemical to its list of toxic air compounds, the first time that had happened since 1990. There are no federal air quality standards for methyl bromide.

The listing was prompted by public outcry over a controversial application by Australian company Malec Brothers. It had proposed using methyl bromide — emitting up to 140 tons per year — to fumigate logs in Delco, in Columbus County, near residential neighborhood and a school. After vehement opposition, the company withdrew its application. 

New rules went into effect last November after more than 18 months’ of often-contentious deliberation at the Science Advisory Board and the Environmental Management Commission.

Now Ecolab, a global company with operations in North Carolina, is requesting a permit to continue to use methyl bromide under those new air quality rules.

One air permit would allow Ecolab to continue fumigating logs and fruit at the port using methyl bromide and phosphine; a second would cover a separate Ecolab log fumigation operation using methyl bromide at Flowers Timber, 90 miles away the in Wayne County town of Seven Springs. 

When fumigating logs with methyl bromide, the gas is pumped into sealed shipping containers or beneath sealed tarps. Ecolab says it will place the tarps inside cold-storage containers. Handheld detection monitors would measure readings during fumigation; any detection outside the sealed containers above 0 parts per million would be considered a leak, according to the draft permit.

After 16 to 72 hours, when concentrations have decreased to or below acceptable levels set by the USDA, the containers are aerated through 40-foot stacks. According to the permit, aeration would be limited to certain times of day, with signs posted stating fumigation is occurring.

The remaining methyl bromide emissions, though, could be dispersed for miles after being released through the aeration stacks — both up into the atmosphere, where it damages the ozone layer, and travels across land and water.

Dangerous chemical, vulnerable communities

Methyl bromide is stealthy. It can’t be seen, tasted or smelled. But depending on the frequency and degree of the exposure to the compound, a person’s lungs may fill with fluid or grow lesions. The kidneys, liver and esophagus can be damaged. A developing fetus might fail to normally grow. Methyl bromide harm the brain, potentially leading to tremors and other neurological damage.

According to a DEQ presentation before the Environmental Management Commission, a large segment of the population also carries a gene that can make them more sensitive to the toxic effects of methyl bromide.

Not surprisingly, the port lies within and near several low-income neighborhoods and communities of color. Data from the DEQ Community Mapping System show the extent of the disparity:

  • More than 55% of the 2,644 residents living in the census block that includes the fumigation operations are people of color;
  • Nearly 72% of the census block is low-income;
  • The rate of childhood and total hospitalizations for asthma in the census block exceeds the state average, by 82% and 64%, respectively;
  • Within one mile of the fumigation operations, there already 18 air pollution sources, as well as many other hazards waste sites;
  • There are several churches within the one-mile radius, as well.

Although in a more rural area, the Wayne County fumigation facility abuts the Red Hawk Mobile Home Park; more than a third of the census block of 989 people are people of color, including a significant Latinx population, and nearly 47% are low-income.

Because several neighborhoods near both facilities contain a large number of native Spanish-speakers, DEQ has recommended translating public information materials into that language. However, state rules don’t require fumigation warning signs to be translated; they have to appear only in English.

Neighbors voice opposition

Several Wilmington residents oppose the permit. They want Ecolab to debark the trees — essentially peeling the logs like a banana — instead of using methyl bromide.

Roman Blahoski, spokesman for Ecolab, told Policy Watch in an email that the company “does not control the decision as to whether methyl bromide or debarking is used. We follow the fumigation requirements for the import country and requests made by our customers.”

Depending on the export destination, some companies do debark their logs. But Blahoski wrote that Ecolab’s customers may require the use of methyl bromide, allowable under the United Nations International Plant Protection Convention, for various reasons: “the use of bark for biofuel, to prevent damage to the log due to drying out, which occurs when the bark is removed; or to assure the termination of all pest life stages, something that is not always achieved through debarking.”

Opponents question the modeling that shows where the chemical would likely travel once it leaves the stacks. The height of the stack is too short — just 40 feet — they say, and given the rampant residential development in the area, the permit underestimates the number of people living within the dispersion zone.

“The monitoring and compliance is a sham,” said Sharon Valentine, who, with her husband, Len Bull, lives about three miles south of the fumigation facility in Wilmington. “They’re monitoring themselves. We don’t know where it will drift. We’re aghast that they’re using methyl bromide this close to the river.”

There is no federal or state drinking water standard for methyl bromide; the EPA recently proposed not regulating it in drinking water because it’s not widely found at high levels there. In rivers, the chemical dissipates relatively quickly, within hours. In lakes, the chemical lasts longer.

Zaynab Nasif, spokeswoman for the Division of Air Quality, said Ecolab facility submitted modeling using proposed emission rates, as well as release points, including velocity and the height at which the gas would be released.  The modeling software uses five years of meteorology and calculates concentrations of the gas offsite. In turn  the division reviews and verifies the modeling to set limits that are trackable and enforceable.

Bull is a retired NC State professor and former associate director of the Animal & Poultry Waste Management Center. He said he is concerned that the modeling fails to accurately show the abrupt changes in wind direction common in Wilmington; conditions at the airport can be different from those at the port, seven miles south, he said. Given these shifts, the chemical could drift west to Leland or east to Wrightsville Beach, he said.

Permit specifics

The proposed permit would allow Ecolab to emit up to 10 tons of methyl bromide each year from its container operation, and nearly five tons from its separate tarp facility. Emissions of phosphine gas — which can harm the respiratory and neurological systems — would be limited to 2.5 pounds per hour.

But the average daily limits in ambient air — in the background — are less stringent than originally proposed by a DEQ toxicologist and the Science Advisory Board.

That 24-hour average was no more than 0.005 milligrams of methyl bromide per cubic meter of air, based on EPA toxicology assessments. After resistance from a few members of the Environmental Management Commission, in 2019 the EMC increased and approved the 24-hour average at 1 milligram per cubic meter — 200 times greater than initially proposed.

Admittedly, it’s difficult to visualize the density of particles this small. Think about the emissions limits this way: First, a cubic meter is about 35 cubic feet, which is roughly equivalent to the cargo space found behind the third seat in a typical minivan. 

Over 24 hours within that space, there can be no more than an average of 1 milligram of methyl bromide. A milligram is roughly 2/10,000th of teaspoon.

Over the course of a year, the acceptable average amount of methyl bromide in the minivan is less, just 0.005 milligrams per cubic meter.

While these levels seem extremely low, they point to just how toxic methyl bromide is — and why its use is restricted.

The average amounts of methyl bromide allowed by the air permit don’t fully capture a worst-case scenario, Bull said. If a large amount were emitted, but then offset later by minuscule amount to reach the average, Ecolab would still comply with its permit. “The averages are less important than the extremes,” Bull said.

Joel Porter, policy manager for CleanAIRE NC, an environmental advocacy group based in Charlotte, said that optimally North Carolina would ban the use of methyl bromide. (Former State Sen. Harper Peterson introduced a bill in 2020 that would have banned the chemical; the measure stalled.) 

“But having a standard as opposed to a free for all is going to do a lot,” Porter said.