originally posted on June 6, 2016

IN REACTION to a letter (“High manganese level in water supply,” Opinion, 5/6/16) warning consumers that Maynilad admitted “high manganese level in (its) raw water supply” at its south concession area (Alabang and vicinity), Jennifer Rufo of Maynilad replied that “the dissolved manganese in the treated water was definitely not at a level that would have any adverse health impact” (“No cause for worry over manganese presence in drinking water—Maynilad,” 5/10/16).

However, she did not state the amount of toxin in its treated water. She also failed to mention the impact of the more dangerous manganese silt or solid particulates that Maynilad advised its consumers to filter with cloth. This vague reply can be misconstrued by consumers as a cover-up. Maynilad should give quantitative figures, and explain the impact of manganese silt.

Consumers had their own tests done by a private firm on dissolved manganese in water. One says 0.01 milligrams per liter. The Department of Health (DOH) standard is 0.4 mg. Safe for now, but how about next time?

The silt surge was not addressed. Silt in home water systems implies the failure of Maynilad’s expensive treatment plant to filter it. Particulates are dangerous as they can reside semipermanently at the bottom of home water tanks, and can sink to the water table, source of deep-well water, which is beyond rehabilitation. An expert said Maynilad might have forgotten to change the silt-laden filter in time.  Whatever the reason, it is unacceptable for a utility to supply manganese silt-laden water to consumers in violation of the law on safe water for consumers. No reply from Maynilad on this point.

The long-term picture is grim. Sourcing potable water from a lake with very little flow, where heavy metals have accumulated through the years and with no rehabilitation efforts, is a very bad idea. I texted Maynilad’s MVP (Manuel V. Pangilinan) about this. His reply was that his expert said it was OK, period. There are deadlier heavy metals like lead and mercury.

Rufo is not clear in explaining dissolved manganese. She simply quotes a DOH paper that it is “not classified as inorganic in the Philippine standard for drinking water.” If it is coming from factories, is it inorganic and toxic?

Rufo states that “it would require exposure to high levels of manganese over a long period before manganism develops.” This is not an excuse. It took the Japanese 20 years to discover mercury poisoning in the village of Minamata, because there were no symptoms from years of slow cumulative ingestion, which eventually killed many. The mercury came from factories, infecting the fish which the villagers ate.

An old study I am trying to trace says there were about 30 heavy metals present in Laguna Lake water and about 350 firms throw their waste there. Laguna Lake Development Authority has no known rehabilitation efforts, yet they exact an environment fee. Are heavy metals at the bottom of Laguna Lake irreversible? Will consumers be plagued again by heavy metal pollution? The National Association of Electricity Consumers for Reforms sent Maynilad a letter demanding answers more than 15 days ago, past the deadline to reply. Please reply.