Faecal

Human exposure to environmental contaminants has been investigated through the analysis of adipose tissue, breast milk, blood and the monitoring of faecal and urinary excretion levels. However, while levels of persistent contaminants in human milk, for example, are extensively monitored, very little is known about foetal exposure to xenobiotics because the concentrations of persistent compounds in blood and trans-placental transmission are less well studied. Also, more information is needed in general about the behaviour of endocrine disruptive compounds (and their metabolites) in vivo, for example the way they bind to blood plasma proteins. 

Thus, it is apparent that soya, some soya products and linseed oil influence blood lipid levels, particularly cholesterol and LDL cholesterol. While the extent of the reduction appears to largely depend on an individual s initial serum cholesterol level, the maximum reductions observed are of the order of 10-15%. For hyperlipidemic individuals this may not be a marked reduction, but such an effect on the general population may well have a beneficial effect on the overall incidence of cardiovascular disease and atherosclerosis. The possibility that non-phytoestrogenic dietary components may contribute to the hypocholes-terolemic properties cannot, however, be discounted. Indeed, certain types of dietary fibre have been shown to have a hypolipidemic effect via their ability to increase faecal excretion rates. 

Indol, CgH N, is the mother substance of the indigo group of compounds. It exists in various essential oils including neroli oil and oil of jasmin flowers. It is a crystalline compound, melting at 52° and boiling at 253° to 254°. Its odour is powerful and disagreeable, being distinctly faecal in character. Its constitution is as follows —... 

Measures to improve the present situation are urgently needed. These measures could be optimized by considering the influence of weather conditions on survival and transport of the microorganisms of faecal origin. 

Origin of the Water-Borne Pathogens and Faecal Indicators Present... 

Rain and Densities of Faecal Pathogens and Indicators in Water Sources. 154... 

The water-related or water-associated infectious diseases are typically arranged in four classes from the environmental engineering point of view, although more complex categorizations have also been proposed [14]. These categories are faecal-oral water-borne diseases, water-washed diseases, water-based diseases and diseases transmitted by water-associated insect vectors. Each type has different causes and potential solutions. Too often the term water-borne disease is erroneously used to name all of them without distinction. 

The faecal-oral water-borne diseases, though with very different intensity, affect both developed and developing countries. These are the most important by number of affected people worldwide (Table 1). The other three categories affect basically developing countries. The water-washed affects those with water scarcity, whereas... 

Table 2 Most important faecal-orai water-borne infectious diseases with their causal agents...

The most important pathogens causing faecal-oral water-borne diseases, with the exception of helmints (Ascaris, Trichurus, Taenia, etc.) are compiled in Table 2. These, virtually absent in the developed countries, are stiU highly prevalent in developing countries, though without causing serious illness [8]. 

Only a small fraction of faecal contaminants contributed to the enviromnent through human and animal faeces reach new hosts to infect them. Many of the defecated microorganisms never reach the soil and/or water bodies, since faecal wastes are submitted to purification (water) and hygienization (solids) processes, which remove a fraction of the pathogens and indicators. An important fraction of those that reach either the soil or water are removed (adsorption to soil particles and suspended solids, followed by sedimentation) and/or inactivated by natural stressors (physical, chemical and biological) in soil and water bodies. 

Abundant literature on the increase of the densities of faecal pathogens and indicators in water sources during dry and rainy periods and the significant effect of rain in water-borne infectious disease outbreaks exist and prove all these assertions. 

First evidences of the impact of heavy rainfall on the epidemiology of enteric pathogens were obtained from studies on the presence of various faecal organisms, both pathogens and indicators in water. Increased numbers of pathogens and indicators in different water bodies, including drinking water, had been reported after heavy rains. 

Increased amounts of faecal-oral water-borne pathogens (virus, bacteria and protozoa) and microbial indicators (bacterial and viral) have been reported in groundwater bodies [18], karst springs [19, 20], surface freshwater [21-26], marine waters used for bathing [27-29] and shellfish growing [30] as well as tap water [31]. 

In contrast, in developing countries published information on this topic is scarce, though existing information indicates that rain levels above background values also increase the amoimts of indicators in fresh water bodies. Blum et al. [32] described in Nigeria a peak period of faecal pollution of water sources in the transition between the dry and the wet seasons. Gasana et al. [33] described boosts of faecal contaminants in water supplies in Rwanda after heavy rain episodes. 

Very little evidence associating water scarcity and an increase in outbreaks of faecal-oral water-borne infectious diseases exists in developed countries. A recent retrospective study performed in England provides some evidence that both low rainfall and heavy rain precede many drinking water outbreaks [3]. Yet, as stated earlier in this review, the situation is potentially different in developing countries [5-7, 9-12], where water scarcity, including droughts, leads to different circumstances that have a clear incidence in the occurrence of both water-borne and water-washed infectious diseases. 

On the contrary, there are numerous reports of outbreaks of faecal-oral waterborne infectious diseases following heavy rain episodes. 

There are some descriptions of water-borne outbreaks, or even small epidemics of acute gastroenteritis (diarrhoea), cholera and hepatitis E associated with catastrophic floods that occurred in developing countries, such as Sudan [34, 35], Nicaragua [36], Mozambique [37] and West Bengal [37]. On the contrary, no changes in the base-line outbreak incidence have been reported in developed countries after major floods [37, 38]. When infrastructures and water management are adequate, outbreaks of faecal-oral water-borne infectious diseases do not follow flood events, even in the case where water flooding has compromised the security of water facilities [37]. 

Kasprzyk-Hordem B, Dinsdale RM, Guwy AJ (2009) Illicit dmgs and pharmaceuticals in the environment - forensic applications of environmental data. Part 2 Pharmaceuticals as chemical markers of faecal water contamination. Environ Pollut 157(6) 1778-1786... 

Hepatitis A virus (HAV) Naked icosahedra 27 nm in diameter Responsible for infectious hepatitis spread by the oro-faecal route especially in children. Also associated with sewage contamination of food or water supplies... 

Propagated outbreaks of infection relate to the direct transmission of an infective agent from a diseased individual to a healthy, susceptible one. Mechanisms of such transmission were described in Chapter 4 and include inhalation of infective aerosols (measles, mumps, diphtheria), direct physical contact (syphilis, herpes virus) and, where sanitation standards are poor, through the introduction of infected faecal material into drinking water (cholera, typhoid). The ease oftransmission, and hence the rate of onset of an epidemic (Fig. 16.3) relates not only to the susceptibility status, and general state of health of the individuals but also to the virulence properties of the organism, the route oftransmission, the duration of the infective period associated with the disease. 

Faecal excretion of vaeeine virus will oeeur and may last for up to 6 weeks. Such released virus will spread to elose eontaets and infect/(re)immunize them. Since the introduction of OPV, notifications of paralytic poliomyelitis in the UK have dropped speetacularly. From 1985-95, 19 of the 28 notified cases of paralytic poliomyelitis were associated with vaeeine strains (14 reeipients, 5 contacts). Vaccine-associated poliomyelitis may occur through reversion of the attenuated strains to the virulent wild-... 

Even if only a relatively small fraction of ingested glucosinolates reach the circulation as the result of metabolism by the gut microflora, degradation of glucosinolates in the faecal stream may be important as a source of... 

The measurement of carotenoid absorption is fraught with difficulties and riddled with assumptions, and it is therefore a complex matter. Methods may rely on plasma concentration changes provoked by acute or chronic doses, oral-faecal mass balance method variants and compartmental modelling. 

---