Spatial and temporal distribution of surface water contaminants in the Houston Ship Channel after the Intercontinental Terminal Company Fire

BACKGROUND: The fire at the Intercontinental Terminals Company (ITC, Deer Park, La Porte, TX, USA) from March 17-20, 2019 resulted in substantial releases of chemical contaminants to the environment, including the surface waters of the Houston Ship Channel. OBJECTIVE: To characterize spatial and temporal trends, as well as potential human health risks, from these releases. METHODS: Out of 433 substances with available data, seven were selected for analysis: benzene, toluene, ethylbenzene, xylenes, oil & grease, suspended solids, and total petroleum hydrocarbons. Spatial and temporal concentration trends were characterized, and hazard quotients and cancer risks were calculated to estimate the potential for human health impacts from these contaminants. RESULTS: Temporal analysis showed presence of these chemical contaminants in water immediately after the event; their concentrations dissipated substantially within 4 weeks. The spatial distribution of contaminants indicated the highest concentrations in the waterways within about 1km of the ITC. The greatest potential human health risks stemmed from presence of benzene. SIGNIFICANCE: A short-term but substantial spike in the concentrations of a number of hazardous contaminants occurred near the incident, with concentrations returning to apparent baseline levels within one month likely due to a combination of volatization, dilution and degradation.