The effective design of sampling campaigns for emerging chemical and microbial contaminants in drinking water and its resources based on literature mining
Hartmann, Julia ; Driezum, Inge van; Ohana, Dana ; Lynch, Gretta ; Berendsen, Bjorn ; Wuijts, Susanne ; Hoek, Jan Peter van der; Roda Husman, Ana Maria de - \ 2020
Science of the Total Environment 742 (2020). - ISSN 0048-9697
Contaminants - Early warning - Emerging - Pathogen
As well as known contaminants, surface waters also contain an unknown variety of chemical and microbial contaminants which can pose a risk to humans if surface water is used for the production of drinking water. To protect human health proactively, and in a cost-efficient way, water authorities and drinking water companies need early warning systems. This study aimed to (1) assess the effectiveness of screening the scientific literature to direct sampling campaigns for early warning purposes, and (2) detect new aquatic contaminants of concern to public health in the Netherlands. By screening the scientific literature, six example contaminants (3 chemical and 3 microbial) were selected as potential aquatic contaminants of concern to the quality of Dutch drinking water. Stakeholders from the Dutch water sector and various information sources were consulted to identify the potential sources of these contaminants. Based on these potential contamination sources, two sampling sequences were set up from contamination sources (municipal and industrial wastewater treatment plants), via surface water used for the production of drinking water to treated drinking water. The chemical contaminants, mycophenolic acid, tetrabutylphosphonium compounds and Hexafluoropropylene Oxide Trimer Acid, were detected in low concentrations and were thus not expected to pose a risk to Dutch drinking water. Colistin resistant Escherichia coli was detected for the first time in Dutch wastewater not influenced by hospital wastewater, indicating circulation of bacteria resistant to this last-resort antibiotic in the open Dutch population. Four out of six contaminants were thus detected in surface or wastewater samples, which showed that screening the scientific literature to direct sampling campaigns for both microbial and chemical contaminants is effective for early warning purposes.
Impact of the invasive alien topmouth gudgeon (Pseudorasbora parva) and its associated parasite Sphaerothecum destruens on native fish species
Spikmans, Frank ; Lemmers, Pim ; Camp, Huub J.M. op den; Haren, Emiel van; Kappen, Florian ; Blaakmeer, Anko ; Velde, Gerard van der; Langevelde, Frank van; Leuven, Rob S.E.W. ; Alen, Theo A. van - \ 2020
Biological Invasions 22 (2020)2. - ISSN 1387-3547 - p. 587 - 601.
Biodiversity threat - eDNA - Gasterosteus aculeatus - Leucaspius delineatus - Pathogen - Pungitius pungitius
The Asian cyprinid Pseudorasbora parva is considered to be a major threat to native fish communities and listed as an invasive alien species of European Union concern. Our study aims to gain evidence-based knowledge on the impact of both P. parva and its parasite Sphaerothecum destruens on native fish populations by analysing fish assemblages and body condition of individuals of native fish species in floodplain water bodies that were invaded and uninvaded by P. parva. We explored the use of environmental DNA (eDNA) techniques to detect S. destruens. Prevalence of S. destruens in native fish species was assessed. Fish samplings showed significantly negative correlations between the abundance of P. parva and the native Leucaspius delineatus, and Pungitius pungitius and three biodiversity indices of the fish assemblages (Simpson’s diversity index, Shannon–Wiener index and evenness). Contrastingly, the abundances of the native Gasterosteus aculeatus and P. parva were positively related. In nearly all isolated water bodies with P. parva, this species is outnumbering native fish species. No effect of P. parva presence was found on body condition of native fish species. Sphaerothecum destruens was demonstrated to occur in both P. parva and G. aculeatus. Gasterosteus aculeatus is suggested to be an asymptomatic carrier that can aid the further spread of S. destruens. Analysis of eDNA proved to be a promising method for early detection of S. destruens, here showing that S. destruens presence coincided with P. parva presence. The ongoing invasion of both P. parva and S. destruens is predicted to pose a significant risk to native fish communities.
Strategies to maintain natural biocontrol of soil-borne crop diseases during severe drought and rainfall events
Meisner, Annelein ; Boer, Wietse de - \ 2018
Frontiers in Microbiology 9 (2018)NOV. - ISSN 1664-302X
Antagonistic interactions - Climate change - Crop - Disease suppression - Extreme weather events - Pathogen - Soil microorganisms
In many parts of the world, agricultural ecosystems are increasingly exposed to severe drought, and rainfall events due to climate changes. This coincides with a higher vulnerability of crops to soil-borne diseases, which is mostly ascribed to decreased resistance to pathogen attacks. However, loss of the natural capacity of soil microbes to suppress soil-borne plant pathogens may also contribute to increased disease outbreaks. In this perspectives paper, we will discuss the effect of extreme weather events on pathogen-antagonist interactions during drought and rainfall events and upon recovery. We will focus on diseases caused by root-infecting fungi and oomycetes. In addition, we will explore factors that affect restoration of the balance between pathogens and other soil microbes. Finally, we will indicate potential future avenues to improve the resistance and/or recovery of natural biocontrol during, and after water stresses. As such, our perspective paper will highlight a knowledge gap that needs to be bridged to adapt agricultural ecosystems to changing climate scenarios.
Understanding preferences for interventions to reduce microbiological contamination in Dutch vegetable production
Asseldonk, M.A.P.M. Van; Malaguti, L. ; Breukers, M.L.H. ; Fels, H.J. van der - \ 2018
Journal of Food Protection 81 (2018)6. - ISSN 0362-028X - p. 892 - 897.
Behavior - Fresh produce - Incentive - Microbiology - Pathogen
Understanding growers' preferences regarding interventions to improve the microbiological safety of their produce could help to design more effective strategies for the adoption of such food safety measures by growers. The objective of this survey study was to obtain insights for the design of interventions that could stimulate growers to increase the frequency of irrigation water sampling and water testing to reduce possible microbiological contamination of their fresh produce. The results showed that price intervention, referring to making the intervention less costly by reducing the price via discounts, is the most effective strategy to change growers' intentions to increase their frequency of irrigation water testing. Moreover, a sense of urgency affects their intentions to increase the frequency of irrigation water testing. The findings of this survey support the hypothesis that, to date, safety is not perceived as a quality control issue under normal circumstances, but safety becomes an overriding attribute in a food crisis.
The effect of different matrices on the growth kinetics and heat resistance of Listeria monocytogenes and Lactobacillus plantarum
Aryani, D.C. ; Zwietering, M.H. ; Besten, H.M.W. den - \ 2016
International Journal of Food Microbiology 238 (2016). - ISSN 0168-1605 - p. 326 - 337.
Food matrix - Gamma factors - Pathogen - Spoilage - Validation
Microbial growth and inactivation kinetics in food can be predicted when the effects of food properties and environmental conditions on microbial responses are available. However the effects of these intrinsic and extrinsic variables on microbial kinetics are often obtained using laboratory media, and deviations between predictions and true behaviour might occur if the specific effect of a food product is not known or considered in the prediction. Therefore, knowing the food specific effect on microbial kinetics might not only result in a more realistic growth and inactivation prediction, but also extend the knowledge on factors influencing growth and heat resistance. In this study, growth predictions of Listeria monocytogenes and Lactobacillus plantarum were validated in laboratory media and in milk and ham as model food products. A good agreement between the predicted and observed growth kinetics in laboratory media highlighted the possibility to predict μmax based on cardinal growth parameters obtained from OD-based measurement in laboratory media. Only in two conditions (BHI pH 5.5 at 7 °C; and BHI pH 5.5, undissociated lactic acid concentration of 1 mM at 7 °C) a possible interaction between growth limiting factors was observed, yet existing interaction models were not better in predicting growth. Growth validation in the two model foods showed that the food specific effects were strain dependent, which might further complicate accurate prediction. For both species the effect of strain variability on thermal inactivation was similar to the food specific effects, and the latter was mainly determined by the effect of ham as heating medium. The combination of both effects explained (almost) all variability found in literature, however, with some bias.