Water-based disease and microbial growth *
Jamie Bartram, Rachel Baum, Peter A. Coclanis, David M. Gute, David Kay, Stéphanie McFadyen, Katherine Pond, William Robertson, Michael J. Rouse in Routledge Handbook of Water and Health, 2015
V. cholerae is commonly associated with marine animals including copepods, shellfish and crustaceans and can be transmitted by marine foods. V. cholerae can occur naturally in marine or coastal waters. They prefer warmer temperatures, reduced salinity and in combination with elevated pH and plankton blooms rapid multiplication of vibrios occur in coastal and estuarine aquatic environments. Serologic studies have resulted in the identification of over 200 different serological O groups within the species V. cholerae. In general, strains outside these serogroups (commonly referred to as “non-O1/non-O139 V. cholerae”) are non-pathogenic or asymptomatic colonizers in humans, or cause mild, sporadic illness (such as gastroenteritis, mild wound or ear infections) in otherwise healthy hosts.
Diphyllobothrium, Adenocephalus, and Diplogonoporus
Dongyou Liu in Handbook of Foodborne Diseases, 2018
Life cycle information has been clarified for D. latum10,61,62,83,102,112,114–116 and D. dendriticum.10,15,61,62,83,102,112,114 The life cycle is as follows: adult tapeworm lays eggs in the small intestine of the definitive host and the eggs are excreted with feces. When the eggs enter water, they develop into a coracidium, a ciliated hexacanth embryo, within an egg for 10–14 days at 16°C–20°C.116 When the coracidium hatches and is released into freshwater, it is ingested by zooplanktonic crustaceans where the coracidium develops into the procercoid in the body cavity of the copepods. A variety of copepods have been identified as the first intermediate hosts, for example, freshwater Cyclops spp. (Copepoda; Cyclopidae),63,117Diaptomus, and Eudiaptomus spp. (Copepoda; Diaptomidae) for D. latum and D. dendriticum.60–62 The coracidium of D. latum takes 2–6 weeks to develop into procercoid larva, depending on the water temperature.116 In an experimental study, it was found that the coracidium of D. nihonkaiense developed into a procercoid within 10–21 days in C. strenuus; however, the copepod species in nature are probably marine species, and much of their information is still unknown.31
The Challenge of Parasite Control
Eric S. Loker, Bruce V. Hofkin in Parasitology, 2015
First, D. medinensis has an Achilles’ heel in its life cycle; Guinea worms are the only helminth parasite that is almost entirely dependent on the consumption of contaminated drinking water to achieve transmission to its definitive host. Furthermore, its transmission is highly focal. In an ironic twist, with Guinea worm we observe a parasite with obligatory aquatic stages that does best under drought conditions. In arid North Africa, where the parasite now makes its last stand, few or no new cases are seen during relatively wet years. But during a drought, as rivers and many water bodies dry up, both humans and copepods increasingly depend on the few isolated water sources that remain. All the elements necessary for increased transmission—humans (including those previously infected), intermediate hosts, and water—converge. Copepods thrive in the warm water, and humans may have no other options when it comes to finding water for drinking, cooking, and bathing. Consequently, control and eradication of Guinea worm can focus on preventing consumption of contaminated water. The strategies to do this in the case of D. medinensis are numerous, simple, and often very cheap. A simple piece of muslin can be used to filter copepods out of drinking water and small handheld filters can be used to insure that any water consumed is copepod-free. Treating water with Temephos, a chemical that kills copepods that is relatively safe for vertebrates, also can interrupt transmission.
Toxicity and biomarkers of micro-plastic in aquatic environment: a review
Published in Biomarkers, 2021
Kamrul Hassan Suman, Md Niamul Haque, Md Jamal Uddin, Most Shirina Begum, Mahmudul Hasan Sikder
Organisms’ can exhibit a wide band of feeding behaviour depending on species, life-stage and prey accessibility, whereas mechano-chemical receptors also contribute in the selection of suitable prey particles (Greene and Landry 1985, Cole et al. 2013). Organisms with more complex intestines (zigzag shaped) and stomachs with a small opening to the intestines have been found to grasp more freshwater plastics increasing the chances of plastic accumulation and strong impairment (Jabeen et al. 2017). Previous experiments identified that MPs uptake by zooplankton was higher due to the indiscriminate feeding modes where prey was often non-selectively fed upon (Cole et al. 2013). Some species found to selectively feed on one species of algae over another species and over plastic beads (Frost 1977, Ayukai 1987). In the copepod Calanus helgolandicus, choice of tiny algal prey has been observed in presence of both MPs and algal prey demonstrated that the copepods could change their feeding modes to discard ingestion of microplastics (Cole et al. 2015).
Comparative study of dissolved and nanoparticulate Ag effects on the life cycle of an estuarine meiobenthic copepod, Amphiascus tenuiremis
Published in Nanotoxicology, 2018
Mithun Sikder, Emily Eudy, G. Thomas Chandler, Mohammed Baalousha
Copepods are the most abundant arthropods on earth, and nearly the most abundant of all metazoans known, rivaled only by nematode round-worms (Giere 2009). For aquatic/marine ecosystems, they are a key to food-web integrity, quality, and sustainability (Hicks and Coull 1983). Impacts of contaminants on the reproductive success of an important prey species could affect the population dynamics of that species and possibly other species dependent on it through selective grazing or predation. Since, A. tenuiremis and other meiobenthic copepods are a key part of the diet of fishes (Gee 1989), shrimps, and crabs (Coull 1990), there is potential for Ag uptake and subsequent transfer to higher level organisms of direct value to humans.
Capturing ecology in modeling approaches applied to environmental risk assessment of endocrine active chemicals in fish
Published in Critical Reviews in Toxicology, 2018
Kate S. Mintram, A. Ross Brown, Samuel K. Maynard, Pernille Thorbek, Charles R. Tyler
Forbes et al. (2001) suggested that the mitigating role of compensatory density dependence often leads to reduced level of effects on populations when compared with effects on individual life-cycle traits. As a consequence, it is possible that current extrapolation methods from individuals to population in ERA may be over-protective. Empirical studies on invertebrates have indicated that exposing a density-limited population (at or approaching carrying capacity) to a toxicant, which reduces survival, growth, and/or reproduction, can reduce the intensity of intraspecific competition and/or predation thus compensating for the toxicant-induced reduction in vital rates (e.g. growth, reproduction, or survival), and thereby reducing the impact on the population as a whole (Liess 2002; Moe et al. 2002). It has also been suggested that a toxicant could remove less fit individuals within a population, promoting population growth, and population fitness (Calow et al. 1997). Population modeling studies have supported this theory. As an example, Grant (1998), applying life-table response experiments, showed that substantial reductions in some vital rates, as a result of toxicant exposure, were compensated for by density dependence in the copepod Eurytemora affinis. Applying matrix models Hayashi et al. (2009) similarly demonstrated that toxic impacts of zinc on populations of the fathead minnow and brook trout (Salvelinus fontinalis) depended largely on the strength of density dependence and differences in life histories. However, empirical studies investigating the role of density dependent processes in the population resilience of fish subjected to chemical exposure are lacking and are much needed to help build confidence in the modeled examples. Furthermore, it should be emphasized that chemical resistance in individuals does not necessarily always equate with desired traits for population relevant measures of fitness i.e. there may be a trade off between chemical resistance and fitness in the absence of chemical exposure.