Monitoring the Houston ship channel for inorganic pollutants by ion selective electrodes, ion chromatography, and inductively coupled plasma spectroscopy

Inorganic pollutants including anions, cations and trace metals were monitored in the surface water of the Houston Ship Channel. The analyses were carried out using ion chromatography (IC), ion selective electrodes (ISE), and inductively coupled plasma emission spectroscopy (ICP). Pollutant composition varied according to sampling sitea and seasonal variations. Nickel, chromium, and arsenic were found throughout the ship channel at an average concentration of 1160 ± 325, 245 ± 26 and 621 ± 78 μg/L for the western end of the channel; 511 ± 48, 407 ± 50, and 545 ± 42 μg/L for the middle section of the channel; and 134 ± 12, 122 ± 16, and 645 ± 33 μg/L for the eastern end of the channel, respectively. Cyanide, ammonia, and nitrite were present at lower levels averaging 5 ± 3, 230 ± 20 and 260 ± 30 μg/L for the western end of the channel; 32 ± 5, 1210 ± 60, and 540 ± 30 μg/L for the middle section of the channel; and 6 ± 2, 590 ± 40, and 340 ± 20 μg/L for the eastern end of the channel, respectively. Phosphate and nitrate concentrations were present at very low levels consistent with the reported low level of eutrophication in the Houston Ship Channel.