New reclaimed water study researchers respond, explain azdailysun.com causes of trichomoniasis

Our results show that there is growth of bacteria in the purple pipes, and that these bacteria carry antibiotic-resistance genes. It is not necessarily a surprise that bacteria are growing in the purple pipes, bacteria grow everywhere and most of them are harmless.

Water conservation is a very important and necessary goal, but to be successful, it is necessary to fully consider potential risks and reduce them to the best practical extent. Several studies around the world have shown that antibiotic resistant bacteria, including pathogens, survive and sometimes even thrive in wastewater treatment plants.

More research is needed on reclaimed water systems to determine what risks they may pose, if any, to increasing background levels of resistance and ultimately the number of people that become ill with infections that cannot be treated with antibiotics.


Resistance genes are encoded in DNA, which can be shared between bacteria. Reclaimed water intended for ‘full body contact’ could affect the natural flora of bacteria on human skin so that they are more likely to carry resistance genes and share them amongst each other.

The question whether these findings raise a public health issue cannot be so easily answered, as there is not enough data provided on the bacteria that are the carriers of such genes (are they alive, are they pathogenic, do they really grow in the pipe system etc.) and on control systems that have been sampled with the same methods (which I deem necessary comparisons).

It seems quite preliminary so it’s really impossible to know what the implications are. They did find some antibiotic resistance genes, but since there were no attempts to also grow bacteria, it’s not clear if these are from living organisms or not.

This area of ARG’s (antibiotic resistance genes) is an interesting one and has some value in identifying locations where antibiotics are being used. When the people of Flagstaff are treated by physicians with antibiotics, it dramatically affects their personal microflora and will increase the presence of ARGs. So, an adult human will be loaded with ARG’s due to past antibiotic use.

Once your treatment is through, the consequences of that therapy lingers on, perhaps for the rest of your life. The field of metagenomics and the microbiome are just now beginning to define the short- and long-term effects of antibiotic therapy.

These effects are not just on pathogens (disease-causing agents), that are the intended target, but also all of our bacterial symbiont. As you know, the bacteria in our bodies outnumber the human cells 10 to 1. Humans are really a large moving vessel to support our bacteria! At least that is what the bacteria think.

The monitoring of ARG’s is not a credible method for assessing risk to human health. This is a research tool that can be used to understand the usage of antibiotics upstream, but there is no established and, really no plausible, link to human health risk.

There also needs to be an epidemiological study performed to establish the link between exposure to the water and human health. I suppose you could start with animal studies to see if they have higher level of drug resistant disease. There are lots of ways, but they need to be rigorous in their design and execution.

There are large international studies that have identified the real threats to antibiotics as therapeutic agents. These involve the misuse of these drugs in 1) animal food production and by 2) physicians in medical practice. In both cases, humans are forcing the evolution of new pathogens with multi-drug resistance phenotypes …

I worry this report mis-directs our attention from the real threats. I am very worried about the development of drug resistant diseases. Waste water and environmental ARGs are not a problem relative the danger we face due to agricultural and medical practices with these very valuable drugs.

If there is real concern about antibiotic resistant pathogens, our activities need to be directed to the real problems and not at treated wastewater. I would predict that Flagstaff residents eat large quantities of ARGS’s daily in their food.

From a relative risk standpoint, the low chance exposure to ARGs in waste water should be compared to the likely high level exposure to ARGs in our food. Not to mention the high ARGs selected for every time you take an antibiotics for illness.