Dialysis Water: Monitoring the quality for hemodialysis and dialysis fluids

Dialysis water is one of the vital component for patient care. There is no denying the fact that drinking water allows the liquid to be processed through the gut and liver, where contaminants are inactivated or removed before absorption into the blood. But when it comes to dialysis water/dialysis fluid, water comes in direct contact with patient’s blood instead of the gut. This impeccably defines the difference and significance of dialysis fluid simultaneously.

To keep dialysis water quality intact, recommendations and international standards are available for the guidance of maximum allowable concentration of contaminants.

Maximum allowable concentration of Microbial Contaminants:

The presence of microbial contamination contributes to the development of biofilm, which in later stage is difficult to remove and results in the release of bacteria and bacterial fragments. These fragments in turn pose serious threat to the patient’s health if appropriate measures are not actualized.

Hence, the maximum allowable concentration as per standard requirements for dialysis water is less than 100 CFU/ml and for Endotoxin it’s less than 0.25 EU/ml. It’s pertinent to mention here that Endotoxins are the major component of outer cell wall of bacteria that are capable of causing severe infection, may lead to organ failure and even death if suitable measures are not taken.

The frequency of microbial testing:

Contaminant	Frequency	Maximum recommended concentration
Microbial Count	Monthly	<100 CFU/ml ( Action Level > 50 CFU/ml)
Endotoxins		0.25 EU/ml ( Action Level 0.125 EU/ml)

BS EN ISO 23500:2015 states there is no requirement to test for bacterial growth or endotoxins when the hemodialysis system is fitted with endotoxin retentive filters that are operated according to the manufacturer’s instructions, unless the manufacturer requires such tests to be performed.

Maximum allowable concentration of Chemical Contaminants:

Various chemicals have been clearly shown to be toxic to dialysis patients at concentrations that are not necessarily toxic to the general population. Those chemicals include aluminum, copper, chloramines, fluoride, nitrate, sulfate, and zinc. Organic chemicals have not been identified as toxic to hemodialysis patients because they are removed through reverse osmosis and carbon adsorption.

Following is the list of maximum allowable concentrations of chemical contaminants in dialysis water for which monitoring is mandatory:

Chemical Contaminant	Maximum recommended concentration (mg/l=ppm)
Aluminium	0.01
Calcium	2 (0.05mmol/l)
Copper	0.1
Fluoride	0.2
Magnesium	4 (0.15mmol/l)
Nitrate (as N)	2 (equates to 9 mg/l NO3
Potassium	8 (0.2mmol/l
Sodium	70 (3.0mmol/l
All of the above chemical contaminants when indicated should be tested initially every 3 months and are mandatory for the monitoring.
Arsenic	0.005
Cadmium	0.001
Chromium	0.014
Lead	0.005
Mercury	0.0002
Sulphate	100
Above group of contaminants for which the drinking water limit is 2 to 5 times the recommended limit for dialysis. In water treated by reverse osmosis, these contaminants will only exceed the limits if they occur at relatively high levels in the water supplied to the unit. These contaminants can be omitted from routine tests if data is available to show that the levels in the water supplied to the unit rarely exceed the limit. Such data is generally reviewed on an annual basis.
Barium	0.1
Beryllium	0.0004
Silver	0.005
Thallium	0.002
Zinc	0.1
The final group of contaminants (barium, beryllium, silver, thallium, tin and zinc) of trace elements are not considered to occur in levels that give cause for concern and, if low levels are present, they are removed effectively by reverse osmosis. Testing is only required if there is evidence of high levels in the local water supply (zinc, for example, can be introduced in the pipework or silver, present if the hospital water supply is treated with silver containing compounds to minimize the presence of Legionella bacteria).  If testing for trace elements is not available, compliance may be demonstrated by compliance with standards for potable water as defined by the WHO or local regulations. If neither of these options is available, compliance can be met through a reverse osmosis system with a rejection of >90 % based on conductivity, resistivity, or TDS.

 References

1. BS EN ISO 13959; 2015:Water for haemodialysis and related therapies

2.European Pharmacopoeia, 8 th ed. Monograph 1167:Haemodialysis solutions, concentrates, water for diluting. European Pharmacopoeia Commission 2014

3. Poli D, Pavone L, Tansinda P, Goldoni M, Tagliavini D, David S, Mutti A, FranchiniI. Organic contamination in dialysis water: trichloroethylene as a model compound. Nephrol Dial Transplant 2006 Jun; 21(6):1618-1625

4. The Water Supply (Water Quality) (England and Wales) Regulations 2000.Statutory Instrument No. 3184.Prescribed concentrations and values .http://www.dwi.gov.uk/regs/si3184/3184.htm#sch1 and http://dwi.defra.gov.uk/stakeholders/legislation/wqregs2007cons.pdf.

5. BS EN ISO 26722; 2015:Water treatment equipment for haemodialysis and related therapies

6. BS EN ISO 23500; 2015: Guidance for the preparation and quality management of fluids for haemodialysis and related therapies

7. JCI 7th Edition 

Arsenic in Drinking Water: Fundamental element of life is threatened by 12th most abundant element

 Arsenic is said to be the 12^th most significant semi-metallic element of the earth crust and commonly found in the atmosphere, soils, rocks, organisms and natural waters. The presence of arsenic in the environment is also associated with anthropogenic (man-made) activities. Arsenic can combine with other elements to form inorganic and organic arsenic compounds.

Acceptable Level of Arsenic in Drinking Water

No doubt, access to clean drinking water is among important indicators determined by the World Health Organization (WHO). SDG-6, one of the UN’s goals claims the same. Hence, various international and national organizations have set up the maximum permissible value of arsenic in drinking water.

The maximum acceptable levels of dissolved arsenic in drinking water are 0.01mg/l which is 10 ppb according to the World Health Organization and the United States Environmental Protection Agency, respectively. However several other countries including Pakistan accepts 0.05mg/l which is 50 ppb. The PSQCA, PEQS and NSDWQ have recommended a limit of 50 ppb for arsenic concentration in drinking water. Following table is showing permissible limits of Arsenic in drinking water:

Water Quality Parameter	Standards	Unit	Permissible Limits
Arsenic	WHO	mg/l or ppm	0.01 mg/l (0.01*1000 = 10 ppb)
	US-EPA guidelines
	IBWA
	FDA
	PEQS 2016 for Drinking Water		<0.05 mg/l (0.05*1000 = 50 ppb)
	PSQCA
	NSDWQ
	IWQS

 The US EPA is of the view that continuous exposure to arsenic over 0.05mg/l results in various health implications. There are number of places in Pakistan where concentration of Arsenic is more than 0.05 mg/l. The US EPA further suggested that by lowering the arsenic standard from 50 to 10 ppb could reduce the probability of multiple diseases.

Arsenic in drinking water and its health implications

In recent decades, water body resources got polluted owing to heavy metals has become one of the serious environmental problems. Humans come into contact with it because it percolates into groundwater from rocks and sediments. Being soluble in water, it exists in ionic forms and affects the humans who consume arsenic contaminated water. Its effects are severe and long-lasting.

It has been said that receiving arsenic through the water and long term exposure can lead to severe health ramifications such as cancer, skin disorders, lung infection, high blood pressure, cardiovascular issues and many other health implications are there in a row. As per International Agency for Research on Cancer (IARC), Arsenic may affect internal organs by impairing their normal functioning without causing any visible external symptoms.

                                 Twelfth abundant element in the nature

Making quality of water denature

A great threat for a living creature

Need to sort out the literature

To save us all from the menace of this miniature 

                                                                            (Haider)

Unfortunately, Pakistan is one of those countries where most of the ground water is contaminated with Arsenic.

ABBREVIATIONS

§  WHO – World Health Organization

§  US EPA – United States Environment Protection Agency

§  PSQCA – Pakistan Standard Quality Control Authority

§  IBWA – International Bottled Water Association Standard

§  FDA – Food & Drug Administration

§  PEQS – Punjab Environmental Quality Standards

§  NSDWQ – National Standard for Drinking Water Quality

§  IWQS – Indian Water Quality Standards

§  IARO – International Agency for Research in Oncology

 

References

1.       'Alarmingly high' levels of arsenic in Pakistan's ground water - BBC News

2.       Zhang L, Ye X, Feng H, et al. 2007. Heavy metal contamination in western Xiamen Bay sediments and its vicinity, China. Mar Pollut Bull 54:974–82. doi:10.1016/j.marpolbul.2007.02.010.

3.       Mohammadi AA, Yousefi M, and Mahvi AH. 2017. Fluoride concentration level in rural area in Poldasht city and daily fluoride intake based on drinking water consumption with temperature. Data Brief 13:12–315. doi:10.1016/j.dib.2017.05.045.

4.       Khan, M.M.H., Sakauchi, F., Sonoda, T., Washio,M., & Muri, M. (2003). Magnitude of Arsenic Toxicity in Tube-well Drinking water in Bangladesh and its adverse effects on human health including cancer, Evidence from the view of literature. Jour Asian Pacific cancer, 4, 7-14.

5.       Kaltreider, R.C., Davis, M.A., Lariviere, P. J., & Hamilton, W. J. (2001). Arsenic Alters the Function of the Glucocorticoid Receptor as a Transcription factor. Journal of Environ Health Perspect, 109, 245–25.

6.       Guha Mazumder, D.N. (2004). Health Hazard caused by chronic arsenic toxicity in West Bengal. Proceedings: Workshop on Medical Geology (IGCP-454), Special Publications No. 83, Geological Survey of India.

7.       Gupta, A.B. and Gupta, S.K. (2004). Recent advances in fluorosis and defluoridaton with special reference to Rajasthan. Proceedings Workshop on Medical Geology, IGCP – 454. Special Publication No. 83, Geological Survey of India.

8.       Analytical Methods for Drinking Water Advances in Sampling and Analysis