An Austrian woman contaminated a sewerage treatment plant with high levels of mercury after traveling to India and bringing back a cream billed as a healing ointment that was loaded with the toxic heavy metal, local authorities announced on Wednesday.

Routine monitoring at a sewerage treatment plant in Upper Austria revealed alarmingly high levels of mercury earlier this year. Workers then started to trace the source of the mercury, which was almost double the allowed limit.

The Department of Water Management first inspected sewer lines from industrial and commercial enterprises in the Vöcklabruck district as well as dental practices but did not find any contaminations.

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Workers tipped of by tealights and a shrine

Using a portable mercury detector, they eventually traced the contamination back to a private residence, 17 kilometers (10.5 miles) away.

The person living in the apartment told workers she had recently visited a wellness center in India where she was given a curative cream and powder to bring home.

Tests revealed the cream contained 32 percent sulfur and 27 percent mercury. The powder contained 36 percent mercury, 20 percent copper and 3.8 percent sulfur.

Free daily tabloid Heute reported the 50-year-old woman was suffering from cancer and bought back 10 kilograms (22 pounds) of the remedies from a monastery. The paper reported she was now also suffering from serious mercury poisoning.

Public broadcaster ORF reported that workers were tipped off by the presence of tealights and a kind of Indian prayer shrine in the woman's apartment. About 4 kilograms of pure mercury reportedly reached the sewer system over several months.

Mercury is an extremely toxic metal that can cause damage to the brain, kidneys and lungs. It can be absorbed through the skin, through vapor or through ingestion.

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Undergoing treatment

Workers destroyed the toxic remedies and helped decontaminate the apartment over the course of a week. The woman is now undergoing medical treatment.

The sewer system between her apartment and the treatment plant are also being decontaminated.

The presence of mercury in waste treatment plants is particularly concerning if the waste is processed into fertilizer for use on crops.

The state water department cited the case as an example of highly effective management, but it also warned people to be careful about the products they buy overseas.

"This shows how well our environmental control functions and how quickly and efficiently we work in an emergency. This prevented an environmental disaster," department director Ulrike Jäger-Urban said in a statement.

Heute reported that the incident cost €100,000 ($122,000).

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