What's in your water? (2 articles)

What’s in your water? Researchers identify new toxic byproducts of disinfecting drinking water

JANUARY 28, 2020

by Johns Hopkins University

https://phys.org/news/2020-01-toxic-byproducts-disinfecting.html

Mixing drinking water with chlorine, the United States’ most common method of disinfecting drinking water, creates previously unidentified toxic byproducts, says Carsten Prasse from Johns Hopkins University and his collaborators from the University of California, Berkeley and Switzerland.

The researchers’ findings were published this past week in the journal Environmental Science & Technology.

“There’s no doubt that chlorine is beneficial; chlorination has saved millions of lives worldwide from diseases such as typhoid and cholera since its arrival in the early 20th century,” says Prasse, an assistant professor of Environmental Health and Engineering at The Johns Hopkins University and the paper’s lead author.

“But that process of killing potentially fatal bacteria and viruses comes with unintended consequences. The discovery of these previously unknown, highly toxic byproducts, raises the question how much chlorination is really necessary.”

Phenols, which are chemical compounds that occur naturally in the environment and are abundant in personal care products and pharmaceuticals, are commonly found in drinking water. When these phenols mix with chlorine, the process creates a large number of byproducts. Current analytical chemistry methods, however, are unable to detect and identify all of these byproducts, some which may be harmful and can cause long-term health consequences, says Prasse.

In this study, Prasse and colleagues employed a technique commonly used in the field of toxicology to identify compounds based on their reaction with biomolecules like DNA and proteins. They added N-α-acetyl-lysine, which is almost identical to the amino acid lysine that makes up many proteins in our bodies, to detect reactive electrophiles. Previous studies show that electrophiles are harmful compounds which have been linked to a variety of diseases.

The researchers first chlorinated water using the same methods used commercially for drinking water; this included adding excess chlorine, which ensures sufficient disinfection but also eliminates harmless smell and taste compounds that consumers often complain about. After that, the team added the aforementioned amino acid, let the water incubate for one day and used mass spectrometry, a method of analyzing chemicals, to detect the electrophiles that reacted with the amino acid.

Their experiment found the compounds 2-butene-1,4-dial (BDA) and chloro-2-butene-1,4-dial (or BDA with chlorine attached). BDA is a very toxic compound and a known carcinogen that, until this study, scientists had not detected in chlorinated water before, says Prasse.

While Prasse stresses that this is a lab-based study and the presence of these novel byproducts in real drinking water has not been evaluated, the findings also raise the question about the use of alternative methods to disinfect drinking water, including the use of ozone, UV treatment or simple filtration.

“In other countries, especially in Europe, chlorination is not used as frequently, and the water is still safe from waterborne illnesses. In my opinion, we need to evaluate when chlorination is really necessary for the protection of human health and when alternative approaches might be better,” says Prasse.

“Our study also clearly emphasizes the need for the development of new analytical techniques that allow us to evaluate the formation of toxic disinfection by-products when chlorine or other disinfectants are being used. One reason regulators and utilities are not monitoring these compounds is that they don’t have the tools to find them.”

More information: Carsten Prasse et al, Chlorination of Phenols Revisited: Unexpected Formation of α,β-Unsaturated C4-Dicarbonyl Ring Cleavage Products, Environmental Science & Technology (2020). DOI: 10.1021/acs.est.9b04926

Journal information: Environmental Science & Technology

Your Antidepressants Are Ending Up in The Environment, Bathing Fish in a ‘Drug Soup’

MIKE MCRAE 10 OCT 2018

For millions of people around the globe, antidepressants are vital medications. Unfortunately, once those pharmaceuticals have done their job inside our bodies, their biochemical effects don’t stop there.

Two researchers from the University of Portsmouth are calling for greater awareness of the risks posed by our prescriptions once they’ve been flushed into the environment, in the hope we might find ways to reduce their ecological impact.

“Our aquatic life is bathing in a soup of antidepressants,” says marine biologist Alex Ford from Portsmouth’s Institute of Marine Biology.

“Antidepressant and antianxiety medications are found everywhere, in sewage, surface water, ground water, drinking water, soil, and accumulating in wildlife tissues.”

And there’s a growing pile of evidence suggesting this ‘soup’ of antidepressants and their break-down products is taking its toll on marine life.

More frightening still are indications that it doesn’t take a high concentration for effects to appear.

“Laboratory studies are reporting changes such as how some creatures reproduce, grow, the rate at which it matures, metabolism, immunity, feeding habits, the way it moves, its colour and its behaviour,” says Ford.

Several years ago, the researcher showed how low levels of selective serotonin reuptake inhibitors such as fluoxetine – the key compound in the antidepressant Prozac – altered the behaviour of amphipod shrimp, causing them to leave sheltered spots more often and risk being preyed upon.

Working with Helena Herrera, an expert in ethical pharmacology, Ford is calling for more research into the risks and benefits of psychotropic prescriptions for the environment in addition to human health.

There’s little question that mood medications help many people deal with chronic levels of clinical depression and anxiety. What is of concern is a growing number of people are turning to pharmacological treatments, increasing levels of psychotropic drugs in the environment.

A study published in 2016 found a 26 percent increase in the use of antidepressants among children and adolescents in the US from 2005 to 2012. The UK saw a 54 percent jump during the same period.

With roughly one in ten people across the Western world on long term courses of antidepressants, this upward trend has the potential to spark an environmental catastrophe.

Without adequate measures for eliminating these chemicals from our waste, we need to ask a hard question – do all of us really need to be medicated, or should we be encouraging alternatives in the name of healthier marine ecosystems?

Swapping pills for therapy or reducing their use won’t work for everybody, but as part of a multipronged approach it could help keep a cap on that growing concentration of psychotropic waste.

Disposal programmes that are tasked with collecting unused medications from patients are already active in many parts of the world, yet vary in their popularity. Improved education could make a significant difference there as well.

“Could educating the medical profession help improve the utility of take back programmes and patient behaviour with regard to drug waste?” the researchers ask.

They’re confident that even small steps would make a big difference.

Other contributions to a solution could include pharmacological companies themselves stepping up and taking a leading role in a ‘cradle-to-grave’ strategy for managing the journey beyond a medication’s delivery.

UK waste management services could also upgrade their infrastructure to reduce the levels of synthetic oestrogens in waste water, they suggest.

“These substances are not currently covered by existing regulations with regards to sewage management, and analytical methods for detection are just now becoming available,” the researchers write.

However we manage it, it’s clear that action is needed, and it’s a problem we can all do something about.

Getting a prescription to antidepressants is a big step forward for many people with a life-changing disorder. Sadly, it means our waterways and estuaries are getting a prescription as well.

This report was published in BJPsych Bulletin.