Questions and Answers Concerning Drinking Water

What are Israel’s drinking water sources? Are these sources exposed to environmental pollutants?
Drinking water supply in Israel is based on the pumping of underground water, surface water and sea water:

The Coastal Aquifer - extends from the mountain edges to the Mediterranean.
The Mountain Aquifer - located along the central mountain line from the Galilee to the Be’er Sheva Valley.
The Kinneret - a natural surface lake receiving water from the Jordan River flows and from other streams in the collection basin.
The Mediterranean and the Red Sea - constitute a source of raw water for desalination, turning them into drinking water.

These sources might be exposed to environmental pollutants. Underground water (water collected in the aquifers and pumped) are potentially exposed to petrol products, industrial pollutants, wastewater, and fertilizers and pesticides. Surface water (streams, reservoirs or the Kinneret) might also be exposed to contamination from industrial, touristic, urban and agricultural activity. Sea water might be exposed to pollutants that flow into the sea (such as wastewater) and petrol products. The agents being monitored in drinking water are substances naturally found in rocks and in the soil, and also environmental pollutants with the potential to penetrate the water.

Are drinking water a major exposure source to environmental pollutants?
Many times, public exposure to a certain pollutant from sources such as food, air or other consumption products is greater than exposure from water. Generally, only 20% of exposure to environmental pollutants is from drinking water, but this value changes based on current knowledge concerning the means of exposure to each specific pollutant. In the case of certain pesticides, for example, exposure from drinking water constitutes only 1% of the total exposure. On the other hand, regarding decontamination byproducts, drinking water are the public’s primary exposure source (about 80%). This is why the standard set for each pollutant takes into account the percentage of exposure from drinking water in relation to the total exposure from that pollutant.

Which agents are regularly checked in drinking water?
The People’s Health Regulations (sanitary quality of drinking water and drinking fountains) include the requirement to regularly monitor approximately 120 environmental pollutants in the drinking water, which have a potential health effect. In addition, about 20 other agents are regularly monitored in the water, which have a potential organoleptic effect, and which typically do not affect health: they might affect the taste, smell, color or temperature of the water.
The substances found in the water can be divided according to their sources and effect on the health of those drinking the water:

Micro-organisms - viruses, bacteria and intestinal parasites that are naturally found in water.
Micro-organisms - from a non-natural pollution source.
Matural substances - chemicals (metals, minerals, radiation components, algae toxins) that are naturally dissolved in water from rock layers.
Pesticides and pollutants of industrial source - chemicals used by man for industry and agriculture (metals, pesticides, industrial pollutants, radiation components), and which might contaminate drinking water sources and penetrate soil layers.
Sea salts and other salt water - when water is close to the sea or to underground salty water bodies, these might penetrate underground water.
Substances for water treatment - residues of substances and byproducts of water treatment processes.

How does the Ministry of Health guarantee that tap water is safe for drinking?
There are regulations for guaranteeing the quality of drinking water, and the Ministry of Health makes sue to update these based on scientific development, accumulate knowledge, analytical developments and international legislation.
Water sources are tested in laboratory tests (for the detection of over 130 different components) before they are approved for supply as drinking water.

A water source that fails to meet the quality or which has been contaminated, is disapproved and cannot be used for drinking water supply. Sometimes, the water source will be approved after the water underwent designated treatment to remove the pollutant.
The water treatment plants are continuously monitored by measurement instruments and are routinely checked in laboratory tests according to the type of the treatment plant. The results of the tests are reported to the Ministry of Health.
The supply systems (pipelines, reservoirs, water towers) are routinely monitored by the water suppliers and the tests’ results are also reported to the Ministry of Health.
All the water supplied to the public are decontaminated with Chlorine. In addition, there residue Chlorine in the water is imperative in order to prevent the development of harmful bacteria.

What is an indicator bacteria and does it indicate the presence of pathogens in the water?
The primary bacteria being monitored in the water systems and constitute indicators for the waters system’s condition, the water’s microbial quality and the risk for morbidity are: coliform bacteria, fecal coliform bacteria, Escherichia coli, fecal streptococci.
These bacteria are found in the digestive systems of humans and warm blooded animals and when they are present in the water it suggests potential fecal pollution.

How is the standard set in the regulations for the agents being monitored in the drinking water?
In Israel, the standards are based on the recommendations and standards of three major international regulatory authorities: the World Health Organization, the US Environmental Protection Agency and the European community. The Israeli standards deviate from these entities’ standards or recommendations only in exceptions where prior Israeli knowledge has been accumulated and which justifies a deviation, or when the standards are not based on health effects.

Does the standard take into account vulnerable populations such as children?
The standard sets a concentration which does not pose a significant health risk under daily exposure throughout a person’s lifetime, including in vulnerable groups (children, pregnant women, the chronically ill and the elderly). Long-term exposure is equivalent to 70 years of human life. The information on the health effects of different chemicals, which constitutes the basis for the drinking water standard, is borrowed from studies on human beings and lab animals.
Regarding most pollutants, the standard is based on the safe threshold of that pollutant, or on the “daily permitted level”. This calculated value includes “safety factors” which reflect the special sensitivity of children, pregnant women, the chronically ill and the elderly and takes into account existing gaps in knowledge. Regarding a number of pollutants without a threshold (cancerous substances), the standard is calculated as the value that exposure to which might cause one event of cancer in a population of 100,000 people, when the entire population drinks water with the same concentration throughout their lifetime. The value represents the maximum risks and takes uncertainty into account.

If the concentration of the pollutant is below the standard, is the water safe for drinking?
When the concentration of the pollutant is below the standard, the meaning is that the water consumption, throughout a person’s lifetime (long-term exposure) does not pose a health risk. As practiced by global regulation, regarding cancerous substances, the meaning is that the water consumption, throughout a person’s lifetime, does not add more than one cancer event in a population of 100,000 people. For isolated cases, such as lead, there is no safe threshold for health effects, and therefore the standard is based on the laboratory’s analytical capabilities and technological abilities to remove it from the water

Are the standards updated from time to time?
An update takes place once every ten years in Israel, as the first regulations were stipulated in 1974. According to the last regulations’ update, a consulting committee to the Ministry of Health will be formed, that will follow the recommendations and standards of international entities and other countries regarding the recommended quality for drinking water, and will review at least every four years, the need to update the regulations.
The regulations’ update incorporated monitoring of agents in the purpose of gathering data as background work towards a future regulation update in Israel. These are agents without global regulation, hence maximum permitted concentrations for these agents have not been set. For example perchlorate, polyaromatic substances, intestinal parasites.

Is there a concerning the regulations for a health effect as a result of exposure to several pollutants?
Sometimes, several pollutants in the same group in the regulations (such as industrial organic substances or pesticides) have a similar or cumulative effect. Therefore, the regulations stipulate the maximum permitted value for each pollutant separately and also require that the sum of the values of the measured agents (of the same group), divided by their maximum concentration values (“relative sum value”) will not exceed 1 or 1.5. This means that if in a particular water source the concentration of each isolated pollutant does not exceed the maximum permitted concentration, but several pollutant are detected and each is in a concentration of over 50% above the standard, the water will be disapproved for drinking. Thus the regulations relate to the possibility of a cumulative effect by several pollutants.

Are chemicals inserted during drinking water treatment and are these supervised?
The water that is pumped from natural sources requires complementary treatment so that it will be of drinking water quality (removal of suspended substances, decontamination etc.). The types of substances used needs to be limited and in addition, the substances’ purity level needs to be stipulated in order to ensure that they will not contaminate the drinking water. All the substances being used for treating drinking water (such as sodium hypochlorite, polyphosphates) must meet the requirements of Israeli Standard 5438 or be approved by the Ministry of Health. The standard stipulates, among others, the requirements for substance purity, its storage, shipment and labeling conditions, as well as the inspection methods appropriate for the product.

Is there a standard for products that come into contact with drinking water such as pipelines and water devices?
All the products that come in contact with drinking water must meet the requirements according to Israeli Standard 5452. In order to meet the standard’s requirements, products undergone comprehensive tests: taste, appearance, metal extraction, possible development of micro-organisms, secretion of toxic substances that might affect living cells and their possible effect in causing genetic mutations.

How can I reduce my exposure to drinking water pollutants?
Most potential pollitants might reach the water source from the environment, and therefore these agents are continuously monitored in the water sources, and if an abnormal agent is detected - the water source is disapproved. Alternatively - the water supplier will erect a water treatment plant to remove the pollutant from the source. The water runs in a closed system that is not exposed to environmental pollutants, only to the materials constructing the supply network. These constructural materilas might affect water quality. Thus, copper, lead and iron that might reach drinking water from pipelines and water devices are monitored. Beyond the responsibility lying with the water suppliers to install devices that meet the required standards, the public has the responsibility to guarantee that the pipelines and devices in their possession are compatible with the stipulations of the Israeli standard. It is recommended to make sure to install and use at home standard plumbing devices which meet the stipulations of Israeli Standard 5452. Under circumstances where there is a concern for plumbing quality (old building, non-standardized plumbing), it is advisable to perform a test of the network’s metals.
In order to reduce exposure to abnormal metal concentrations as much as possible, please find several tips:

Avoid consumption of first water for drinking and cooking (including preparation of baby formula) after the water stood for some time, and allow the first water to run for several seconds.
Avoid consumption of the hot water for drinking and cooking as much as possible.
Avoid consumption of highly murky or colored water for drinking and cooking due to the possibility of the presence of metals. Usually, allowing the water to run a little refreshes the water in the system and fresh water arrives.

How can I obtain information on the concentration of substances being monitored in the drinking water which are supplied to my place of residence?
According to the People’s Health Regulations (the sanitary quality of drinking water and drinking water fountains), the water supplier must publish an annual report for the public on its website. The report will include a summary of the findings of the microbial and chemical tests that the supplier performed, while highlighting deviations, if such were found. For further information, the local water supplier may be contacted. The Ministry of Health published an annual rpeort on the quality of drinking water, which includes national and data and data by districts, regarding the quality of the water in the eater sources and the supply systems.

What are polyaromatic substances?
Polyaromatic substances are byproducts of petrol processing and burning. Many compounds are cancerous at low concentrations. They are not soluble in water, but due to their potential risk, they are monitored in the drinking water.

The water does not taste good and I decided to install a local treatment device - what are the recommendations of the Ministry of Health?
The Ministry of Health recommends drinking tap water. Tap water in Israel is everywhere safe for drinking. If, despite this, you have decided to install a water treatment device in your home or place of business, make sure that:

The device meets the Israeli Standard (Israeli Standard 1505)
The device must be used according to the manufacturer’s instructions, including: replacement of filters and UV bulbs on time. (Failure to replace these on time and according to the manufacturer’s instructions might pose a health risk and a bed for bacteria proliferation).
If the device includes chemicals, make sure they meet the Israeli Standard (Israeli Standard 5438).

Following these rules will prevent health risk.

Why doesn't the Ministry of Health recommend the instalment of home treatment devices?

Tap water is safe for drinking. The water supply network is controlled and monitored by the water suppliers and supervised by the Ministry of Health.
Home water treatment devices are not always regularly controlled and undergo maintenance.
The filters of treatment devices with a filtering system might accumulate pollutants: solids, bacteria and chemicals. An incidental malfunction in the filters might cause these pollutants to penetrate (at high concentrations) the drinking water.
Failure to maintain correct use and follow the manufacturer’s instructions might also result in water that is not safe for drinking.

I have nevertheless decided to purchase a water treatment device, what are tour guidelines on this issue?
We emphasize again that tap water in Israel are good and safe for drinking and home devices are unnecessary,but please find several guidelines nonetheless:

Only buy a device that meets the stipulations of Israeli standard number 1505: “home drinking water treatment systems - filtering and purification”.
Follow the manufacturer’s instructions on maintenance, replacement of filters, bulbs etc.
Use of home device is allowed only when used on tap water of drinking water quality.
In the event of a drinking water contamination where the public (including those who have a home device) are required to follow the instructions of the Ministry of Health, such as boiling the water, contact the manufacturer and consult them whether maintenance actions or equipment replacement should be performed.
Please note that Israeli Standard number 1505 has been declared official, and therefore the sale and import of home treatment devices that do not meet the standard are prohibited. The Ministry of Trade, Commerce and Industry is responsible for the supervision and enforcement of this issue.

I am constructing a house - how do I know which type of plumbing to install so that the water is safe for drinking?
The Ministry of Health has issued Israeli Standard 5452 for materials and devices that come in contact with drinking water.
Make sure that the pipes and devices being installed meet this standard and that they are approved by the Standards Institution. The requirement is that the planning and instalment of the water system are made according to Israeli Standard 1205. The chemicals used for cleaning the plumbing are required to meet Israeli Standard 5438.

There is a drinking water tank in the building I live in for the residents’ use - how can I guarantee that the water quality is maintained?

The tank must be closed well, without the possibility of penetration by animals or foreign objects.
The tank will be locked, without access, except for the Home Committee or its representative.
The water tank’s surface shall be smooth and intact.
Perform cleaning and decontamination as necessary.

When should the building’s water tank be cleans and decontaminated?

In a new building - after instalment and prior to use
Following repairs or replacement of devices
If a pollution was detected in the tank
When the water has an organoplastic problem (murkiness, taste, odor, color)
Once a year, according to Israeli Standard 1525.

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