Assessing the Acute Gastrointestinal Effects of Ingesting Naturally Occurring, High Levels of Sulfate in Drinking Water

Abstract

Concerns regarding the health effects from sulfate in drinking water have been raised because of reports that diarrhea may be associated with ingesting water that contains high levels of sulfate. Of particular concern are groups in the general population (i.e., infants and transients) that may be at greater risk from the laxative effects of sulfate when they switch abruptly to drinking water with high sulfate concentrations. There have been a number of studies of the effects of sulfate in the drinking water of domestic animals (cattle, swine, and poultry), and most report minimal adverse effects from exposure to fairly high levels of sulfate. Anecdotal reports and case studies suggest that people suffer gastrointestinal effects when exposed to drinking water containing high levels of sulfate. However, there have been few experimental studies of the effects of sulfate on adults, and only two epidemiologic studies designed to assess the effects of high levels of sulfate on infants, and it is not yet possible to accurately determine the concentration of sulfate in drinking water that will produce adverse human health effects.

Effects of Sulfate-Rich Mineral Water on Functional Constipation: A Double-Blind, Randomized, Placebo-Controlled Study

“…No SAEs and only 10 mild or moderate AEs were reported, with 2 minor AEs possibly being related to the treatment (meteorism with mineral water and diarrhea with placebo). This is in accordance with a review showing an association between higher sulfate content in water and an increase in stool frequency, but no association with diarrhea up to 2,800 mg/l or other AEs, even in infants [32].…”

Theoretical and Practical Aspects of Biological Sulfate Reduction: A Review

“…However, at concentrations above 600 mgL -1 , sulfate can affect the taste of water and can have laxative effects (Silva et al, 2012). High concentration has been reported to cause diarrhea and dehydration in human beings (Backer, 2000). Infants are more prone to the higher sulfate concentration than adults.…”

Approach to the Patient with Diarrhea

“…Nonabsorbable sodium anion laxatives such as Na 2 PO 4 (neutral phosphate) or Na 2 SO 4 (Glauber or Carlsbad salt) and high concentrations of SO 4 2in naturally occurring drinking water [272] induce osmotic diarrhea. When these substances are ingested factitiously, these diarrheas may be difficult to detect because these substances do not result in a calculated osmotic gap on stool analysis (see Evaluation of severe or elusive diarrhea).…”