Dear Editor,
It seems that the majority of Guyanese are more concerned about the sexual escapades of a self-proclaimed “Pope” rather than what is being put into the water that comes through their taps. While the “Pope scandal” has been the most trending topic for the past week, what should have been a real controversy has gone virtually unnoticed. That is, the admission by the GWI that they have used Antinfek (active ingredient PHMB) to, as the Stabroek News of November 10, 2016 put it, “disinfect the Diamond Well Station and another at Hillfoot along the Linden/ Soesdyke Highway”. Apparently it was the Director of Operations of GWI who made that disclosure according to the same news article. That admission came after the CEO of GWI defended the chemical saying that its active ingredient is already being used in numerous products. What the CEO failed to tell the population is whether or not the chemical is being used outside of Guyana for the treatment of potable water. It boggles the mind that these officials do not seem to understand the concept of context and application. It is one thing to use a chemical as a disinfectant or antiseptic for the treatment of wounds, in swimming pools, in slaughter houses among other uses but it is another to assume that that same chemical can also automatically be used for the treatment of potable water.
The first problem is the fact that there is so little information available on this chemical regarding its safety for use in potable water treatment. In fact with a simple Google search one comes up with a paucity of studies on the safety of polyhexanide, also known as polyhexamethylene biguanide (PHMB) for the treatment of water to make it potable. The European Chemicals Agency (ECHA) has prepared a document that proposes how polyhexanide should be classified and labelled. For example, the substance is classified as lethal when inhaled, is suspected of inducing cancer, may cause allergic skin reaction, causes serious eye injury, and damages the respiratory system upon repeated exposure. Due to its status as lethal when inhaled, polyhexanide was prohibited in cosmetic products from January 1, 2015. The Scientific Committee on Consumer Safety concluded that the substance is not safe for use in cosmetic products including cosmetic spray formulations up to a concentration of 0.3%.
During my very limited research I found one study (Isaac J. Asiedu-Gyekye et al.; Toxicological assessment of polyhexamethylene biguanide for water treatment) looking into the safety of the chemical in humans for water treatment. The study was conducted on Sprague-Dawley rats. Gross pathology and histopathology revealed that the integrity of the major organs (of the rats that were studied) was compromised especially at high doses (of polyhexanide). Of course this finding has implications when considering the use of polyhexanide in treating water to make it potable. The authors of the study recommend that chronic toxicity studies be done to ascertain the long-term effects of the chemical.
So one has to question whether or not the folks at GWI really understand the chemical they are defending so vigorously. Even if what they are saying is true; that they are just conducting pilot studies with the substance. I’m curious as to the nature of those studies because it is obvious that not much is known about the effects of long term exposure to the chemical. The GWI must say if it is equipped and competent enough to conduct the scientific research required to ascertain whether or not Antinfek is safe for use in potable water treatment applications.
The Guyanese public deserve to know exactly how Antinfek has been used by GWI in the past and how it is currently being used including the details of the pilot studies being undertaken by the company.
Yours faithfully,
Peter John
GWI customer
