MATTOON, Ill. (WAND) - The City of Mattoon has reissued a do not drink order after a harmful algal bloom has made the water unsafe to drink.
The city said in a press release Tuesday evening that the algal bloom was found at 0.38 parts per billion level, above the advisory level of 0.3 parts per billion.
This is higher than the testing results that were shared previously by the City of Mattoon. According to officials, samples first taken from the Mattoon Water Treatment Plant detected microcystin levels at 0.35 parts per billion (ppb).
Concentrations of toxin are just above the threshold Illinois set for children.
- Harmful lever for adults: 1.6 µL/L
- Harmful level for kids: 0.3 µL/L
- Mattoon's level: 0.35 µL/L
Residents should not drink tap water, only use bottled water for drinking, preparing food and baby formula, brushing teeth, washing dishes, and making ice. They should also not attempt to treat the water. Boiling, freezing, filtering, or adding disinfectants will not remove the toxin.
Mattoon lifted its previous do not drink order July 13 after lasting for over two days.
Mattoon City Manager Kyle Gill told WAND News that on July 2, the ILEPA came in to test the water, and detected the microcystin at .216, which is within the safe range. When they returned to test on July 10, the microcystin was at .35. Because this was above the .30 limit, the ILEPA required Mattoon to release a "Do not drink order."
Gill said they do not have confirmation as to when the microcystin reached a dangerous level, but are working to determine ways to start testing for it themselves.
The city is unsure when the new order will be rescinded and is awaiting further information from the IEPA.
The algal bloom was caused by the hot, sunny conditions the area has seen lately.
Symptoms of poisoning with this microtoxin are similar to norovirus (stomach issues). It can cause a rash if on the skin, however, ingesting it is worse than contact on the skin.
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