By Samantha M. Howe, Petrochemical Accident Researcher
On April 1, 2011, the EPA issued an information collection request to oil refineries in the United States under the Clean Air Act requiring them to monitor what was being released from their stacks.[i] The results were shocking. On January 8, 2013, ExxonMobil Baton Rouge Refinery released an update to their initial report on December 9, 2011 reporting a release of hydrogen cyanide from their Fluid Catalytic Cracking Wet Gas Scrubber. They report that they were releasing anywhere from 44.3 lbs/day to 444.3 lbs/day of hydrogen cyanide with an estimated amount of 22,000 lbs released in the previous year; the reportable quantity for hydrogen cyanide according to the National Response Center is 10 lbs/day or 3650 lbs per year. The numbers submitted by ExxonMobil were determined using engineering estimates due to a change in estimating methodology instead of the refinery’s best professional judgment.[ii]
Hydrogen cyanide is a colorless liquid, that sometimes has an odor of bitter almonds, but most of the time is odorless. It boils at the low temperature of 78.8; the resulting gas is lighter than air and tends to dissipate quickly in a well-ventilated area. It was first isolated in 1786 from Prussian blue dye, but cyanide has been recognized as a poison since ancient times. Many states use cyanide gas as the agent of choice when carrying out judicial death sentences. The Nazis also used a form of hydrogen cyanide gas in the gas chambers in their concentration camps.[iii]
Lethality for gaseous hydrogen cyanide is 100-300 parts per million (ppm) with death usually resulting within 10 minutes to up to an hour; initial symptoms of cyanide poisoning can occur from exposure as low as 20 to 40 ppm. Symptoms of acute cyanide poisoning include headaches, drowsiness, vertigo, weak and rapid pulse, a bright red color in the face, and nausea and vomiting. While current research shows that cyanide does not accumulate in the body, studies have shown that chronic exposure to hydrogen cyanide can cause central nervous system toxicity and thyroid problems.[iv] Cyanide prevents the cells of the body from using oxygen causing cell death or necrosis; this is particularly traumatic for the brain and heart as these organs use the most oxygen in the body.[v] In the often cited 1975 study by El-Ghawabi of workers in an electroplating factory with chronic exposure to hydrogen cyanide he noted the symptoms of central nervous system toxicity, they include: headaches, weakness, and changes in both taste and smells.[vi] The loss of oxygen to the brain cells could be what is causing these symptoms.
In several of the workers from this study, they had enlarged thyroids or goiter.[vii] This is due to the chronic exposure to thiocyanate, which is the principal metabolite of cyanide;[viii] the thiocyanate vies with iodine in the thyroid, inhibiting iodine uptake in the process.[ix] Iodine is essential for the thyroid in order to produce the necessary metabolism hormones along with many others the body needs; iodine deficiency can lead to goiter and hypothyroidism.[x]
Hypothyroidism is of great concern in populations exposed to hydrogen cyanide on a regular basis. This is particularly concerning in pregnant women, a study found that pregnant women with subclinical hypothyroidism were twice as likely to have a preterm birth and were also three times more likely to have a placental abruption. It has been found that in babies born to mothers who had severe maternal hypothyroidism during their pregnancy had long-term impairment of behavior, locomotor ability, speech, hearing, and cognition. Unfortunately these effects are irreversible. In cases, it has been found that those neonates who had moderate hypothyroidism, an immediate supplementation with a thyroid hormone can restore neurological development functions to some amount. Women are also more likely to develop goiter and hypothyroidism, especially those who already have a low iodine intake. In addition, those with low iodine intake that are also exposed to other chemicals and pollutants that act in the same way as thiocyanate are also at risk of developing hypothyroidism. These chemicals include perchlorate and nitrates; both of which are also regularly being released and/or used by oil refineries. Unfortunately, the effect of co-exposure of cyanide and other chemicals is not fully known. It has been noted that acute exposure to both hydrogen cyanide and carbon monoxide results in hypoxia and death, but low-level chronic exposure is not known. Protein deficiencies might also make people more susceptible.[xi]
Right now the Louisiana Department of Environmental Quality does not monitor for hydrogen cyanide at any of its air monitoring facilities. Hopefully, this will change in the future as there are ways to measure the concentration; these include a two air dispersion models specifically developed by the EPA to simulate air pollution resulting from emissions from industrial sources. Studies have shown that both the ISCST3 and AEROMOD are fairly accurate in modeled concentrations of hydrogen cyanide.[xii]
As stated in the first paragraph; after stack testing was mandated by EPA, ExxonMobil Baton Rouge Refinery reported their estimated hydrogen cyanide emissions for 2012, they reportedly released 22,000 lbs of hydrogen cyanide throughout the year. However, that number is still on the low side of what is truly being released; when the upper and lower bounds of their stack tests are averaged out it comes out to be approximately 244.47 lbs/day. This number is then multiplied by 365 to figure out what the yearly average between the high and low bound estimates should be; this calculation comes out to 89,229.73 lbs of hydrogen cyanide released throughout 2012 (this average indicates hydrogen cyanide emissions were 4 times greater than what ExxonMobil reported for 2012).[xiii]
While there is still more information being submitted concerning the hydrogen cyanide releases at oil refineries around the state (including Phillips 66 Alliance Refinery in Belle Chase submitting a National Response Center report regarding continuous release above Reportable Quantity of 10lbs/day),[xiv] there is still plenty that can be done to monitor the emissions better. As stated earlier the LDEQ currently does not monitor for hydrogen cyanide although there is equipment that will allow for it. We need to make sure that LDEQ gets this equipment in order to better protect the people living in communities around and downwind from these refineries. In addition, monitoring at the flare needs to become mandatory and the pollutants being monitored should be specific to each facility based on the products they produce. While the amounts of hydrogen cyanide being released aren’t enough to kill a person immediately, they are enough to make someone ill. The people of Louisiana deserve to breathe clean air; the people of Louisiana deserve to healthy; the people of Louisiana deserve better.
[i] U.S. Environmental Protection Agency . (2012, October 16). Comprehensive Data Collected from the Petroleum Refining Sector. In Technology Transfer Network: Air Toxics Web Site. Retrieved July 17, 2013, from http://www.epa.gov/ttn/atw/petref/petrefpg.html
[ii] Louisiana Department of Environmental Quality, Electronic Document Management System, http://www.louisianarefineryaccidentdatabase.org/incident.php?serno=4819, LDEQ Incident # 135706
[iii] Stewart, C. (2010). Cyanide as a Chemical Weapon: A Review. In Fire Smoke Coalition. Retrieved July 17, 2013, from http://www.firesmoke.org/wp-content/uploads/2010/10/Cyanide_As_A_Weapon.pdf
[iv] International Cyanide Management Institute. (n.d.). Environmental & Health Effects. In International Cyanide Management Code for the Gold Mining Industry . Retrieved July 17, 2013, from http://www.cyanidecode.org/cyanide-facts/environmental-health-effects
[v] Centers for Disease Control and Prevention. (2013, June 27). Facts About Cyanide. In CDC Emergency Preparedness and Response. Retrieved July 17, 2013, from http://www.bt.cdc.gov/agent/cyanide/basics/facts.asp
[vi] El Ghawabi, S. H., Gaafar, M. A., El-Saharti, A. A., Ahmed, S. H., Malash, K. K., & Fares, R. (1975). Chronic Cyanide Exposure: a clinical, radioisotope, and laboratory study. British Journal of Industrial Medicine, 32, 215-219. Retrieved July 17, 2013
[viii] Orloff, K. G., Kaplan, B., & Kowalski, P. (2006, June). Hydrogen cyanide in ambient air near a gold heap leach field: Measured vs. modeled concentrations. Atmospheric Environment, 40(17), 3022-3029. Retrieved July 17, 2013
[ix] U.S. Environmental Protection Agency . (2010, September). Toxicological Review of Hydrogen Cyanide and Cyanide Salts. InEPA Integrated Risk Information System (IRIS). P.64. Retrieved July 17, 2013, from http://www.epa.gov/iris/toxreviews/0060tr.pdf
[xi] IBID, ix.
[xii] Orloff, K. G., Kaplan, B., & Kowalski, P. (2006, June). Hydrogen cyanide in ambient air near a gold heap leach field: Measured vs. modeled concentrations. Atmospheric Environment, 40(17), 3022-3029. Retrieved July 17, 2013
[xiii] IBID, ii.