Local Biotechnologist Comments on American Advisory | Should Barbadians be Concerned About ELEVATED Levels of Bacteria in the Water? | Should Food Establishments on the South Coast be Closed by Government?
Dr. Robert D. Lucas
A press conference was held on the 26th. January that sought to clear the air over the discrepancies in microbial findings and interpretation of the potable water quality on the south coast of Barbados. The Americans found that there were elevated counts of microorganisms (this was not refuted by the local authorities) and advised their citizens to boil the water before drinking it. The Barbados’ government position is that Salmonella, coliforms and E.coli (fecal indicator (FI) organisms) were not detected and therefore the potable water on the south coast complied with the World Health Organization’s (WHO) guidelines. The press conference was aired live on the Voice of Barbados (VOB), and it was admitted by the Barbados Water Authority (BWA) that it had increased the level of chlorine added to the potable water supply on the south coast of Barbados. It was disclosed by the Minister of Health, that he became particularly concerned when it was revealed by the Americans that the advisory affected the area where he lives among other areas (it appeared that he was only interested in saving his own hide).
The following is written in the public interest. Let me start by saying that the Americans are correct in the position that they have adopted and that the local authorities are skating on thin ice, as I will now show…
There are other fecal indicator organisms also recognized by WHO. These are fecal streptococci, Clostridium perfringens among others. What are of importance from a microbial aspect of the above disclosures are the elevated numbers of organisms detected and the increasing levels of chlorine being used. When added to water, chlorine forms chlorous acid, which is able to penetrate bacterial cell walls, and disrupts protein synthesis resulting in death. It also attacks organic matter and indeed this is one of the drawbacks when using chlorine based-disinfectants. In other words, the greater the organic matter load of water, the greater the amount of chlorine which has to be used to attain a specific disinfectant level Fecal matter is highly organic in nature and therefore it is correct for the local authorities to up the levels of chlorine used. The problem, however is that the exact amount of fecal matter seeping into the potable water cannot be ascertain plus the microorganisms continue to grow and multiply and therefore estimates have to be made. This is starkly revealed by the elevated counts obtained by the Americans. From the disclosure the following events have occurred. Note we are dealing with hard science not law, economics or political science.
1. There was a high level of organic matter present in the water (could be fecal in nature or derived from food processing operations) and most of the chlorine disinfectant was used up in reacting with it.
2. Microorganisms were present at what is known in microbiology at levels too numerous to count (TMC); and since microorganisms are organic in nature, the disinfectant was not present at concentrations adequate to destroy all of them.
3. A combination of one and two occurred.
There is a risk associated with the use of chlorine as a disinfectant at high concentrations. At 200 parts per million (ppm) there is no carcinogenic risk associated with its use. At 1000 ppm chlorine is carcinogenic. BWA must in the public interest state what levels of chlorine have been used in an effort to achieve safe potable water.
Increasing levels of disinfectants increase the selective pressure on microorganisms and can result in pathogenic genes being passed from pathogenic organisms to non-pathogenic ones creating unwanted problems.
In any event, elevated levels of microorganisms indicate that something is wrong and the absence of the presence of fecal indicators does not preclude their presence at some time prior to the testing. The local authorities should therefore advise citizens in the affected areas to boil their drinking water, given that at the same press conference, the BWA admitted that the situation was getting worse.
The local authorities have been keeping a lot of noise about the gastroenteritis outbreak not being associated with the sewerage problem. They have not demonstrated the following:
Four criteria that were established by Robert Koch to identify the causative agent of a particular disease, these include:
the microorganism or other pathogen must be present in all cases of the disease
the pathogen can be isolated from the diseased host and grown in pure culture
the pathogen from the pure culture must cause the disease when inoculated into a healthy, susceptible laboratory animal
the pathogen must be reisolated from the new host and shown to be the same as the originally inoculated pathogen
Have the authorities grown the suspected causative viral agent in cell culture or have they used a DNA probe to substantiate their claim? Proof must be presented.
From food safety aspects, establishment dealing in food in the area affected should not have a say in whether or not to open or close their shops. Under the hazard analysis critical control (HACCP) system, which is considered the Holy Grail designation for food establishment, there are certain prerequisites, which must be met. These are sanitary standard operating procedures (SSOP’s) and current good manufacturing practices (cGMP). Absence of filth and obnoxious smells fall under these prerequisite conditions. Since currently, in the affected area these conditions are not being met, all such establishment should be closed by law. I train members of the Environmental Health Department at the Barbados Community College (BCC). The last time one of my students closed down a food establishment I wrote about it and the print media would not publish the article. It was published online and I was fired and actually received a letter from a prominent attorney giving me two-weeks to retract the article or be sued for libel. I ignored the joker. Last year I was at BCC teaching the students again. Most likely I will be fired again for writing this, which is neither here nor there with me.
Robert D. Lucas, PH.D.