Drinking blue water is a popular, yet potentially toxic, water source. 

It comes from the ocean, lakes and ponds and is used by people for drinking, cooking and bathing.

But there is no easy way to stop the contamination.

A new paper published in Environmental Health Perspectives finds that when the drinking water is filtered to remove contaminants, the amount of blue drinking-water in the water can drop by up to 30%.

The paper, by researchers at the University of California, Berkeley, examined the health effects of blue water contamination and found that if the water source was filtered, blue drinking waters did not cause any health problems, but they did contain harmful contaminants.

“The blue drinking source is also a water source that is considered unsafe for drinking,” the paper reads.

“However, because of the way blue drinking has been filtered, it is unlikely that blue drinking sources are the source of these harmful contaminants.”

The study was conducted by a team of researchers at UC Berkeley, the University at Buffalo, and the University College London.

They found that filtering blue water was no more effective at reducing the amount or amount of contaminants in drinking water than white or red water.

The researchers say that, while the amount and amount of contamination in the blue water may be similar, the contaminants were still found in different ways.

“We found that it was possible to detect the presence of blue contaminants at lower levels than in red water,” said study co-author Jessica Zwicker.

“However, when the sample was filtered and then further purified, blue was found to be slightly more prevalent in the drinking-stream water.”

The researchers suggest that more research is needed to understand how the blue drinking medium can be filtered.

“This could help us to better understand how drinking water quality is affected by the filtering process, and if the filtering method itself can be modified to remove these contaminants,” they write.

“While it may seem counterintuitive, it’s also possible that other factors, such as temperature, pH or the water’s chemistry can affect the levels of blue in drinking-waters.”

The authors of the study said that the results suggest that drinking blue water poses a health risk.

“Because the water is not filtered, contaminants can remain in the source water,” they wrote.

“Additionally, we found that even if the source was purified, there was still some level of blue contamination in drinking waters.”

They add that it may be important to consider what you are drinking when choosing a water supplier, or how much of the water you are consuming.

“Although the amount detected in drinking aquifers may not be large, they may still be detectable,” they said.

“If your water source is not in pristine condition, or if you have a family member who is sensitive to water quality, consider how much you consume and when to drink.”

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