Drugs get a second chance to enter our bodies – via wastewater and fish...
Blinky the three-eyed fish is quite endearing in The Simpsons, but you probably wouldn’t want contaminated fish on your plate. Mohammad Mottaleb, Adjunct Professor in chemistry at Northwest Missouri State University, used GC-MS (with selected ion monitoring) to discover ng/g levels of anti-histamine diphenhydramine (Benadryl), anti-anxiety drug diazepam (Valium), and anti-seizure carbamazepine – and their metabolites – in fresh- and salt-water fish species purchased from regular grocery shops (1). Eleven of fourteen fish investigate were found to be contaminated.
These potentially harmful yet readily available products are released as discharge from sewage treatment plants, having entered the system via human urine and feces or through inappropriate disposal from drug manufacturers and hospitals. And according to Mottaleb, the trend shows no signs of abating. “Continuous loading of the parent compounds and metabolites of pharmaceuticals and personal care products (PPCPs) will reach harmful concentrations that adversely affect the freedom of aquatic creatures. And eating contaminated fish might have consequences for human health effect hazards over period of time,” says Mottaleb.
Mottaleb suggests one of the major problems is the lack of effective contaminant removal techniques in water treatment plants, which are not generally designed to eliminate pharmaceuticals. He also notes that reduction in contaminants depends on an assumption of collective responsibility, which calls for increased awareness, beginning with the regulatory authorities and filtering down to health care professionals and consumers. “Consumers need to be aware of the consequences of PPCPs to aquatic organisms and ecosystems, and should follow regulatory agency disposal guidelines to make our environment friendly for all living organisms.”
At the same time, Mottaleb suggests, science professionals play a crucial role in addressing the challenge of PPCPs as emerging contaminants. This is particularly important in the light of a more recent discovery: traces of illegal drugs in surface water and river waters. “Scientists and toxicologists should continue to investigate the transport, fate, toxicity and their potential physiological and psychological effects on humans and wildlife as well as the relationship between bioaccumulation and diseases. Our research group is investigating those illegal drugs in fish from these rivers – periodic measurements of exposure level of those compounds are very important.”
- MA Mottaleb et al., “Pharmaceuticals in grocery market fish fillets by gas chromatography–mass spectrometry”, Food Chem, 190, 529-36 (2016). PMID: 26213006.
A former library manager and storyteller, I have wanted to write for magazines since I was six years old, when I used to make my own out of foolscap paper and sellotape and distribute them to my family. Since getting my MSc in Publishing, I’ve worked as a freelance writer and content creator for both digital and print, writing on subjects such as fashion, food, tourism, photography – and the history of Roman toilets. Now I can be found working on The Analytical Scientist, finding the ‘human angle’ to cutting-edge science stories.