Spotlight 15/01/18 | Biofilms on the watch list

In the week the UK Prime Minister declared a crackdown on plastic waste, we should take time to consider the many forms pollution can take, including contamination of the environment with pharmaceutical waste.

A recently published article (E. Rosi et al. Urban stream microbial communities show resistance to pharmaceutical exposure. Ecosphere, 2018 DOI: 10.1002/ecs2.2041) notes the increased detection of polluting chemicals in urban streams, from antihistamines to antibiotics to caffeine, much of which stems from sewerage effluent. Wastewater treatment facilities are seemingly insufficient to completely remove biologically active chemicals. Furthermore, they associate such factors with heightened resistance of environmental bacteria from polluted urban settings compared to samples from less polluted sub-urban settings, including to the antibiotic, ciprofloxacin.

Bacteria in fresh water often exist as multi-species communities known as biofilms, exposure of which to pollutants can alter their diversity and taxonomic profile. Since biofilms are long-lived, hardy structures, they act as a reservoir for resistant bacteria. Not only is this potentially of concern to human health, as with the bacterium, Aeromonas spp. which can cause gastrointestinal infection, but it also has implications for the natural saprophytic functions of such biofilms. ‘One health’ has become a somewhat trendy term, but arguably the environmental aspect of the One Health trinity (along with human and animal health) is comparatively marginalised. If we can shine a spotlight on human behaviour resulting in excessive plastic waste, we surely could, and should, place everyday chemical waste equally high on the agenda. A holistic solution to the AMR cause may just depend on it.