Thermal death points for common parasites and pathogens – composting guide gas prices going up in michigan


Infection is spread by the hand to mouth transmission of eggs resulting from scratching the anus, as well as from breathing airborne eggs. In households with several members infected with pinworms, 92% of dust samples contained the eggs. The dust samples were collected from tables, chairs, baseboards, floors, couches, dressers, shelves, window sills, picture frames, toilet seats, mattresses, bath tubs, wash basins and bed sheets. gas dryer vs electric dryer calculator Pinworm eggs have also been found in the dust from school rooms and school cafeterias. Although dogs and cats do not harbor pinworms, the eggs can get on their fur and find their way back to their human hosts. In about one-third of infected children, eggs may be found under the fingernails.

Pregnant female pinworms contain 11,000 to 15,000 eggs. Fortunately, pinworm eggs don’t survive long outside their host. Room temperature with 30% to 54% relative humidity will kill off more than 90% of the eggs within two days. At higher summer temperatures, 90% will die within three hours. Eggs survive longest (two to six days) under cool, humid conditions; in dry air, none will survive for more than 16 hours.

One of the worst consequences of pinworm infestation in children is the trauma of the parents, whose feelings of guilt, no matter how clean and conscientious they may be, are understandable. However, if you’re composting your manure, you can be sure that you are not thereby breeding or spreading pinworms. Quite the contrary, any pinworms or eggs getting into your compost are being destroyed.36

The eggs are passed in the feces and mature into larvae outside the human host in favorable conditions. The larvae attach themselves to the human host usually at the bottom of the foot when they’re walked on, then enter their host through pores, hair follicles, or even unbroken skin. They tend to migrate to the upper small intestine where they suck their host’s blood. Within five or six weeks, they’ll mature enough to produce up to 20,000 eggs per day.

Hookworms are estimated to infect 500 million people throughout the world, causing a daily blood loss of more than 1 million liters, which is as much blood as can be found in all the people in the city of Erie, PA, or Austin, TX. An infection can last two to fourteen years. gas oil Light infections can produce no recognizable symptoms, while a moderate or heavy infection can produce an iron deficiency anemia. Infection can be determined by a stool analysis.

Roundworms (Ascaris lumbricoides) are fairly large worms (10 inches in length) which parasitize the human host by eating semi-digested food in the small intestine. gas z factor The females can lay 200,000 eggs per day for a lifetime total of 26 million or so. Larvae develop from the eggs in soil under favorable conditions (210C to 300C/69.80F to 860F). Above 370C (98.60F), they cannot fully develop.

Approximately 900 million people are infected with round-worms worldwide, one million in the United States. The eggs are usually transmitted hand to mouth by people, usually children, who have come into contact with the eggs in their environment. Infected persons usually complain of a vague abdominal pain. Diagnosis is by stool analysis.39 An analysis of 400,000 stool samples throughout the U.S. by the Center for Disease Control found Ascaris in 2.3% of the samples, with a wide fluctuation in results depending on the geographical location of the person sampled. Puerto Rico had the highest positive sample frequency (9.3%), while samples from Wyoming, Arizona, and Nevada showed no incidence of Ascaris at all.40 In moist tropical climates, roundworm infection may afflict 50% of the popu-lation.41

Roundworms, like hookworms and whipworms, are spread by fecal contamination of soil. Much of this contamination is caused and spread by children who defecate outdoors within their living area. One sure way to eradicate fecal pathogens is to conscientiously collect and thermophilically compost all fecal material. Therefore, it is very important when composting humanure to be certain that all children use the toilet facility and do not defecate elsewhere. When changing soiled diapers, scrape the fecal material into a humanure toilet with toilet paper or another biodegradable material. It’s up to adults to keep an eye on kids and make sure they understand the importance of always using a toilet facility.

The second factor is time. grade 9 electricity formulas The lower the temperature of the compost, the longer the subsequent retention time needed for the destruction of pathogens. Given enough time, the wide biodiversity of microorganisms in the compost will destroy pathogens by the antagonism, competition, consumption and antibiotic inhibitors provided by the beneficial microorganisms. Feachem et al. state that three months retention time will kill all of the pathogens in a low-temperature composting toilet except worm eggs, although Table 7.14 (also from Feachem) indicates that some additional pathogen survival may occur.

A thermophilic compost pile will destroy pathogens, including worm eggs, quickly, possibly in a matter of minutes. Lower temperatures require longer periods of time, possibly hours, days, weeks, or months, to effectively destroy pathogens. One need not strive for extremely high temperatures such as 650C (1500F) in a compost pile to feel confident about the destruction of pathogens. It may be more

realistic to maintain lower temperatures in a compost pile for longer periods of time, such as 500C (1220F) for 24 hours, or 460C (1150F) for a week. According to one source, "All fecal microorganisms, including enteric viruses and roundworm eggs, will die if the temperature exceeds 460C (114.8°F) for one week." 42 Other researchers have drawn similar conclusions, demonstrating pathogen destruction at 500C (1220F), which produced compost "completely acceptable from the general hygienic point of view." 43

A sound approach to pathogen destruction when composting humanure is to thermophilically compost the toilet material, then allow the compost to sit, undisturbed, for a lengthy period of time after the thermophilic heating stage has ended. The biodiversity of the compost will aid in the destruction of pathogens as the compost ages. If one wants to be particularly cautious, one may allow the compost to age for two years after the pile has been completed, instead of the one year that is normally recommended.

In the words of Feachem et al., "The effectiveness of excreta treatment methods depends very much on their time-temperature characteristics. The effective processes are those that either make the excreta warm (550C/1310F), hold it for a long time (one year), or feature some effective combination of time and temperature." The time/temperature factor of pathogen destruction is illustrated in Figure 7.7.

However, humanure contains the potential for harboring human pathogens, including bacteria, viruses, protozoa and parasitic worms or their eggs, and thereby can contribute to the spread of disease when improperly managed or when discarded as a waste material. When pathogenic raw humanure is applied to soil, pathogenic bacteria may continue to survive in the soil for over a year, and round-worm eggs may survive for many years, thereby maintaining the possibility of human reinfection for lengthy periods of time.

Thermophilic composting requires no electricity and therefore no coal combustion, no acid rain, no nuclear power plants, no nuclear waste, no petrochemicals and no consumption of fossil fuels. The composting process produces no waste, no pollutants and no toxic by-products. 10 gases and their uses Thermophilic composting of humanure can be carried out century after century, millennium after millennium, with no stress on our ecosystems, no unnecessary consumption of resources and no garbage or sludge for our landfills. And all the while it will produce a valuable resource necessary for our survival while preventing the accumulation of dangerous and pathogenic waste.