In July 2014, Tesoro Corporation announced plans to build a xylene extraction facility at the site of its existing oil refinery in Anacortes, Washington. The $400 million facility would be capable of producing 15,000 barrels per day for export to Asia in oceangoing vessels.

Yet xylene is a little-known chemical, and it’s worth asking: what is the risk of xylene to Northwest communities?

In case you skipped Sightline’s 101 course, xylene is liquid petrochemical distilled primarily from partly refined crude oil. It’s a starting point for plastic bottles, polyester fibers, food packaging, paint, rubber, and more. But before xylene becomes a Coke bottle with your name on it, it would start as crude oil that is partially refined into “reformate.” (Reformate is easier to produce from light oils, such as the Bakken shale oil delivered by train to the site.)

Then it would undergo an extraction process at the Puget Sound refinery, which involves manufacturing, transferring, treating, and storing the chemical. Finally, every couple of weeks, the refinery operators would load a tanker vessel at Tesoro’s Anacortes wharf and ship it across the Pacific.

All by a company with a less than spectacular safety record. If any of the operations resulted in a spill, the xylene could pose meaningful risks both to the residents of nearby Anacortes and to the non-human inhabitants of the Salish Sea. Even without incident, emissions of xylene could contribute to air pollution and illness.

Xylene is listed by the federal Agency for Toxic Substances and Disease Registry (ATSDR), a division of the US Centers for Disease Control and Prevention, for  several known and suspected health risks, some short-term and some chronic.

Short-term exposure to xylene is known to cause difficulty breathing, impaired memory, and delayed response to visual stimulus, among other issues. At very high levels of short-term exposure, people have died.

Long-term exposure can lead to depression, insomnia, tremors, and more. An article in the Journal of Occupational and Environmental Medicine reported symptoms like anxiety, forgetfulness, and inability to concentrate from regular exposure after many years. Short- and long-term exposures to higher concentrations of xylene can impact the nervous system, causing headaches, reduced muscle coordination and balance, and confusion.

Less understood—or yet to be studied in humans—is a range of worrisome effects that have observed in xylene-exposed animals. These include complications for the kidneys, heart, and nervous system, all of which have been identified in high-level, short-term exposure in animals. Animals also lost hearing, had muscle spasms, showed changes in enzyme activity and organ weights, and experienced skin inflammations, according to federal toxicologists.

  • Federal government researchers also acknowledge that pregnant mother exposed to xylene may pass the chemical’s effects along to the fetus, as studies on animals have shown that xylene absorbed by a mother can cross the placental barrier. Unborn animals impacted by xylene exposure may have reduced body weight and delayed bone mineralization, as well as problems with motor skills and orientation to their environment after birth.

    An article in the Journal of Oral and Maxillofacial Pathology cited the risk of xylene leaking into soil, streams, or groundwater. When a large xylene spill enters the soil, it can travel into the groundwater, contaminate drinking water, and remain for several months before it breaks down. Researchers know relatively little about the amount of xylene in surface water.

    Though it’s most likely to enter your body when you breathe its vapors, xylene exposure for humans or wildlife can also occur through ingestion or contact to the eyes or skin. Inhaled, xylene is rapidly absorbed by your lungs, and your body will retain 50 to 75 percent of the chemical after you exhale. If ingested, the chemical is rapidly and completely absorbed by your gut. According to the Agency for Toxic Substances and Disease Registry, xylene can also dissolve into the skin’s natural oils and can easily penetrate clothing or get trapped in gloves or boots, where it can cause burns and blisters. Xylene passes into your bloodstream quickly after entering your body but generally leaves the body within 18 hours after exposure.

    The most severe health effects are from exposure to short-term, high concentrations of the chemical, as might happen after a spill. However, an April 2015 study published by researchers at the University of Colorado and The Endocrine Disruption Exchange found xylene among the culprits causing hormone disruption even at levels currently deemed “safe” by federal regulators during regular indoor air exposure.

    A 30-day public comment period on county permits for Tesoro’s project just closed. If the project is approved by the state Department of Ecology, Tesoro says it aims to begin construction in 2016 and start producing xylene in a year or two.

    Addendum: The current comment period, which has concluded, will help the County determine the threshold of review under the State Environmental Policy Act (SEPA). Once the County makes that determination, officials will open up another comment period tied to the SEPA process itself. Bottom line: it’s not too late to weigh in on this project. Stay tuned.