Drinking Water Mineralization

Water Quality Products invited Stan Hazan, senior director of regulatory affairs and association programs for NSF International, to comment on the outcome of the International Symposium on Health Aspects of Calcium and Magnesium in Drinking Water held in April.

WQP: Please give us a brief overview of the three-day symposium on the health effects of calcium and magnesium in drinking water held in April.

Stan Hazan: The symposium, held in Baltimore, Md., was attended by 162 participants from 25 countries who represented academia, government, industry, medicine and public health. The three-day meeting thoroughly reviewed the current scientific knowledge on the nutritional requirements and health effects of calcium (Ca) and magnesium (Mg), as well as the technical feasibility and economics of their addition to drinking water, and framed the issues for the World Health Organization (WHO) Expert Meeting that followed.

WQP: Why did NSF International, the International Life Sciences Institute (ILSI) and the NSF/WHO Collaborating Centre develop the symposium?

Hazan: NSF and the ILSI were interested in this issue because of the potential health benefits that had been postulated for Ca and Mg, and the scientific discussions that have taken place on nutrition and diet, dietary supplementation and water as one of the potential sources of these key minerals. Given the rapidly increasing consumption of desalinated and other low- mineral waters, this symposium represented an appropriate opportunity to collect the science for discussion by all parties.

NSF and ILSI’s stakeholders have keen interest in drinking water quality, and NSF wanted to help the WHO arrive at a scientifically defensible position when establishing guideline values for Ca and Mg. All of the participants and members of the audience—who ranged from medical professionals, academics, epidemiologists and chemists to engineers, water treatment product manufacturers, and beverage bottling and marketing representatives—learned much from the symposium.

WQP: What were some of the main topics discussed at the symposium?

Hazan: The symposium consisted of more than 30 presentations delivered in 10 sessions. The major session topics were:

  • Dietary Minerals Consumption and Health;
  • Water as a Source of Dietary Minerals in World Regions;
  • The Basis for Linking Mg, Ca and Health Outcomes I & II;
  • Controlled Human Exposure Studies of Mg and/or Ca in Diet and Drinking Water;
  • Epidemiological Evidence Linking Drinking Water Components and Health - Cardiovascular and Other Diseases I & II;
  • Alternative Hypotheses and Knowledge Gaps;
  • Water Production, Technical Issues and Economics; and
  • Roundtable/Summaries/ Conclusions/Discussions.

In general, there was agreement that Ca and Mg are essential nutrients, and that there is evidence to show that daily intakes below threshold levels can be detrimental to human health, with postulation that additional health benefits are possible when intakes exceed average levels. Much discussion centered on trying to identify those benefits and attempting to quantify them for various at-risk populations.

Many technical issues were discussed, including the distinction between soft and softened water. The issue of corrosion control attracted participation from the water treatment, water supply and bottled beverage industries. Water treatment industry representatives argued that it is not the role of drinking water to provide nutritional benefits (notwithstanding fluoridation), and compared establishment of minimum mineral concentrations in drinking water to mandatory medication. This focused attention on whether hard water requirements, however beneficial they might be, were an issue of public health or public policy. A significant issue for some participants was consideration of Ca and Mg independently, without including effects of other drinking water constituents.

The final Roundtable Session was quite energized as Joe Cotruvo, principal conference organizer, and Jamie Bartram of the WHO fielded questions and listened to alternate opinions.

WQP: What would be the potential effect on the U.S. water treatment market if experts determine that there is a relationship between health and Ca and Mg in drinking water, and that they should not be removed when treating drinking water?

Hazan: Certainly, the issue of water mineralization represents challenges and opportunities to the water treatment industry, both at the municipal and residential/commercial markets, and for bottled water and other beverages, and even for food nutrition and dietary supplements. If the WHO recommendations move in the direction of establishing minimum guideline levels of Ca and Mg, the impact is expected to be greater in Europe than in North America, and the recommendations would likely require time to exert an impact on current water treatment practices.

While the final results of the WHO Expert Meeting are awaited, it is certain that drinking water mineralization will continue to attract considerable attention and debate. The attendees seemed to agree that the conference brought forth the best available information and represented another successful event for NSF, the ILSI and the WHO, and for the numerous sponsors, including the WQA, Coca-Cola and Nestle, and IPWR, KIWA, VITENs, Kinetico, Pentair, Aqua Europa, Aqua Belgica, Kureha Engineering, Regal Ware and many others.