Rashes, burning and itching eyes, lung congestion and other ailments recently have plagued many Upcountry Maui residents. But because the county stopped adding phosphoric acid to the water system on Monday, the problem are expected to decline in the next few days.
More than 140 residents have complained to the county Department of Water Supply since mid-2001, when the department added a different compound — zinc orthophosphate — to the Upcountry water system. This action was taken in response to a federal order to reduce lead leaching from older plumbing.
Although the department switched to phosphoric acid last year, the complaints continue.
The county this month received permission from the Health Department's Safe Drinking Water Branch to use soda ash, or sodium carbonate, which adjusts the pH of water, reducing acidity and resulting in less corrosion within the pipes.
Before the symptoms disappear, state health officials want to document the cases for future study. Today through Monday, Department of Health staff will be at various Upcountry community centers to briefly interview residents and take photographs.
District health officer Dr. Lorrin Pang said yesterday that preliminary study of a possible link between the water additives and health problems showed that Upcountry residents who traveled reported that their skin conditions improved within three days of leaving Maui. And the conditions resurfaced within three days of returning home.
Pang said one theory is that phosphoric acid may not be directly responsible for the skin irritations. Instead, the compound might be acting as fertilizer for as-yet unidentified microbes or germs. He said water samples have been taken and frozen for future study.
He also noted that soda ash will slightly raise the sodium level in drinking water, but that residents on low-sodium diets need not be overly concerned.