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Any link between desalinated water and cancer / osteoporosis? Any documentation that can be refered to to refute such claims?


Online article circulated in Gaza where desalinated water for drinking water is main source. Regardless of its quality / authorship, we need to be able to refute based on recognised technical body. Many thanks!

3 Answers


There is probably no simple answer to this. Information can be found in the World Health Organisation document on desalination and some of the references that it gives.

The definitive guidelines on drinking water quality are the WHO (2011) Guidelines for drinking-water quality, 4th ed. Geneva, World Health Organization but you would have to determine what elements are of concern from your source water, process and any re-mixing with non-desalinated water.

Osteoporosis is mentioned in the following link;

You can look up details of any chemical element of concern at;


The particular situation in Gaza means that even if there are risks associated with desalination, water from private or commercial desalination plants is probably still the safest available. The only possible better source would be rainwater harvesting for those with sufficient roof area and enough storage to carry them through the dry summer months.

The public water treatment works and distribution network have been destroyed by military action and wells in the Gaza portion of the Coastal Aquifer are so contaminated by sewage and agro-chemicals that only 5-10% of the water is safe to drink and the situation is deteriorating. The UN recommends immediate cessation of use of this water to protect the health of those who use it and to allow the recovery of the aquifer.

With the exception of the north of Gaza, the concentration of fluoride in the groundwater is higher than the WHO standard of 1.5 mg/l. The most affected areas are Khan Younis (2.7 mg/l) and Rafah (2 mg/l). While at low concentrations fluoride reduces the risk of dental cavities, higher concentrations can cause dental fluorosis which results in discolouration of teeth, pitting and alteration of tooth enamel. This can be seen in the teeth of many of the people in Gaza. Even higher intakes of fluoride taken over a long time can result in changes to bone, a condition known as skeletal fluorosis. This can cause joint pain, restriction of mobility and increased risk of bone fractures. Some studies suggest that high fluoride levels may also impair the brain function. Strontium and chrome have also been detected in the water of Gaza.

In most parts of Gaza the nitrate (NO3) concentration in groundwater is far above the WHO accepted guideline of 50 mg/litre. Levels go as high as 331 mg/litre. The health risks posed by high nitrate levels include Methemoglobinaemia (blue baby syndrome) which prevents haemoglobin in the blood from binding with oxygen which particularly affects infants. The disease can cause breathing difficulties, fatigue, headaches and loss of consciousness. It can have a serious impact on a child’s development. Nitrate contamination can also affect pregnant women and may increase the risk of some kinds of cancer.


There is no major study or systematic review on this topic yet, probably in light of the fact desalination was not a predominant technology for water supply until recently, but the key of the answer lies in how much drinking water contributes to the daily calcium intake, which depends mainly on dietary habits.

It is worth mentioning, however, that a 2013 study from Israel found that "Mg and Ca intakes may be significantly lower among individuals consuming desalinated water" suggesting mineral addition to water prior consumption as a solution. However, the same study suggests more research is needed with greater samples, to assess impacts on people's health. 27115.pdf