poster - International Conference of Agricultural Engineering

FIGURE 1 – Project tasks and links
3. Discussion and Conclusions
The intended research constitutes an evolution of the state of the art relative to the ARB risk
assessment in Coimbra Region. It will provide the first survey for ARB in the distribution and
drainage waters in this Area. The expected results per sampling site as well as their spatial
and temporal variability throughout the model watercourses selected are: (i) total numbers of
cultivable bacteria; (ii) biochemically identified antibiotic-resistant bacteria to family or genus
level; (iii) the antibiotic resistance profile per isolate towards different classes of antimicrobial
agents; (iv) detection and identification of different classes of ARG, responsible for
antimicrobial resistance; (v) putative evidences of the ability to antibiotic resistance gene
horizontal transference among strains, through transconjugants assays. These data will be
analysed to infer about the inputs and outputs of ARB and their resistance genes along the
waterway and therefore clarify the contribution of different activities in the widespread of
these genes in the environment.
The project will reveal the percentage of multidrug resistant bacteria (and specifically of
Enterobacteriaceae) in water networks and Mondego River and therefore will inform about
the exposure risk through contact with surface waters. This contact may occur during animal
drinking or crops irrigation with contaminated water. Conversely, as antibiotics are needed
for animal infections treatment, the ARB can end up in surface water, through runoff of
manure. Another expectable source is the discharge of treated or untreated wastewaters
coming from hospitals, where people also are treated with antibiotics. This research will
contribute for public health and environmental risk assessment, providing information about
the real impact of each activity to environmental exposure and vice-versa.
Concluding, this survey will allow inferring about the impact of hospital, urban and rural
activities in the spread of ARG in the water network, namely in the distribution and drainage
systems and water for agricultural uses. Those activities are expected to load ARB into water
environments, as they are originated from human and animal sources. Such detailed
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