Radboud University
Over the past 20 years, concentrations of pharmaceuticals have increased
in freshwater sources all over the world, as research by environmental experts
at Radboud University has revealed. Levels of the antibiotic ciprofloxacin have reached the point of potentially causing damaging ecological effects.
The research is the first to examine the risks of two particular medicines in global freshwater sources, and is being published in Environmental Research Letters on 22 February. “The study calls for more widespread data gathering to measure the problem around the world.”
“Getting an accurate
picture of the environmental risks of pharmaceuticals around the world depends
on the availability of data, which is limited,” says Rik Oldenkamp, lead author
of the article.
“It's true that there are models, such as the ePiE model, which can give detailed predictions of pharmaceutical concentrations in the environment, but these are often only applicable to places where we already have a lot of information, such as rivers in Europe.”
“It's true that there are models, such as the ePiE model, which can give detailed predictions of pharmaceutical concentrations in the environment, but these are often only applicable to places where we already have a lot of information, such as rivers in Europe.”
The new model
developed by the researchers, which builds on an existing model with a lower
resolution, makes it possible to come up with worldwide predictions for
individual ecoregions.
For the two
pharmaceuticals investigated in the study – carbamazepine, an anti-epileptic
drug, and ciprofloxacin, an antibiotic – the environmental risks were found to
be 10 to 20 times higher in 2015 than in 1995. The increased human use of
ciprofloxacin was found to have a particularly high impact globally.
“The concentrations of
this antibiotic can be harmful for bacteria in the water, and these bacteria in
turn play an important role in various nutrient cycles,” says Oldenkamp.
“Antibiotics can also have a negative impact on the effectiveness of bacteria
colonies used in wastewater treatment.”
The environmental
risks of ciprofloxacin in fresh water have increased worldwide between 1995 and
2015. PNEC stands for 'predicted no effect concentrations'. Credits: R.
Oldenkamp et al, Environmental Research Letters
Antibiotic resistance
as an environmental issue
Antibiotic resistance
has been on the agenda of the World Health Organization (WHO) and United
Nations General Assembly for a few years now. “Generally, it’s seen as a
problem for the health sector, as resistant bacteria can be spread within
hospitals or through livestock,” says Oldenkamp.
“But there’s little awareness of the role of the environment in this problem, even though it becomes increasingly clear that the environment functions as a source of resistance for various pathogens.”
“But there’s little awareness of the role of the environment in this problem, even though it becomes increasingly clear that the environment functions as a source of resistance for various pathogens.”
More data in high-risk
areas
“Our model predicts a
relatively high environmental risk for ecoregions in densely populated and dry
areas such as the Middle East, yet those are precisely the areas where there is
little data on pharmaceutical use and concentrations in surface waters,” says
Oldenkamp.
The researchers predicted human pharmaceutical consumption in these areas using regression models based on consumption in other countries, along with socio-economic and demographic information, and linked this to information related to other factors such as water sources and the number of people with access to wastewater treatment.
The researchers predicted human pharmaceutical consumption in these areas using regression models based on consumption in other countries, along with socio-economic and demographic information, and linked this to information related to other factors such as water sources and the number of people with access to wastewater treatment.
“Our model shows a
particular need for new data in these types of areas,” says Oldenkamp. “The
model is really a starting point for creating an insight into the environmental
risks posed by pharmaceuticals all over the world.”
Publication
Aquatic risks from human pharmaceuticals – modelling
temporal trends of carbamazepine and ciprofloxacin at the global scale. 2019. Environmental
Research Letters.