Biomedical subjects

M M Karpiscak

Publications and source records attributed to M M Karpiscak.

7 recordsLinked to original sources

PubMed2002

Giardia and Cryptosporidium removal from waste-water by a duckweed (Lemna gibba L.) covered pond.

AIMS: To determine the ability of duckweed ponds used to treat domestic waste-water to remove Giardia and Cryptosporidium. METHODS AND RESULTS: The influent and effluent of a pond covered with duckweed with a 6 day retention time was tested for Giardia cysts, Cryptosporidium oocysts, faecal coliforms and coliphage. Giardia cysts and Cryptosporidium oocysts were reduced by 98 and 89%, respectively, total coliforms by 61%, faecal coliforms by 62% and coliphage by 40%. There was a significant correlation between the removal of Giardia cysts and Cryptospordium oocysts by the pond (P < 0.001). Influent turbidity and parasite removal were also significantly correlated (Cryptosporidium and turbidity, P=0.05; Giardia and turbidity, P=0.01). CONCLUSIONS: The larger organisms (parasites) probably settled to the bottom of the pond, while removal of smaller bacteria and coliphages in the pond was not as effective. SIGNIFICANCE AND IMPACT OF THE STUDY: Duckweed ponds may play an important role in wetland systems for reduction of Giardia and Cryptosporidium.

Animals↗

PubMed2001

Fate of indicator microorganisms, Giardia and Cryptosporidium in subsurface flow constructed wetlands.

Limited information is available on the ability of subsurface flow wetlands to remove enteric pathogens. Two multi-species wetlands, one receiving secondary sewage effluent and the other potable (disinfected) groundwater were studied from February 1995 to August 1996, at the Pima County Constructed Ecosystems Research Facility in Tucson, Arizona. Each wetland had a retention time of approximately 4 days. The objectives of this study were (1) to evaluate the ability of multi-species subsurface wetlands to physically remove Giardia cysts; Cryptosporidium oocysts, total and fecal coliforms, and coliphages; and (2) to determine the likely impact of local wildlife on the occurrence of these indicators and pathogens. In the wetland receiving secondary sewage effluent, total coliforms were reduced by an average of 98.8% and fecal coliforms by 98.2%. Coliphage were reduced by an average of 95.2%. Both Giardia cysts and Cryptosporidium oocysts were reduced by an average of 87.8 and 64.2%, respectively. In the wetland receiving disinfected groundwater, an average of 1.3 x 10(2) total coliforms/100 mL and 22.3 fecal coliforms/100 mL were most likely contributed by both flora and fauna. No parasites or coliphages were detected.

Animals↗

PubMed2001

Removal of pathogenic and indicator microorganisms by a constructed wetland receiving untreated domestic wastewater.

Wetlands containing floating, emergent and submergent aquatic plants, and other water-tolerant species have been found to economically provide a mechanism of enhancing the quality of domestic wastewater. The use of constructed wetlands for the removal of indicator bacteria (total and fecal coliforms), coliphages, protozoan parasites (Giardia and Cryptosporidium) and enteric viruses was investigated. A pilot scale constructed wetland consisting of two cells, one planted with bulrush and the other unplanted bare sand, were used to compare their efficiency in removing pathogens from raw sewage. Overall more than 90 percent of all microorganisms studied were removed by either of the two systems with a 1 to 2 day retention time. Removal of all mentioned microorganisms was greater from the surface flow in the unplanted cell than in the planted cell, except for Giardia and Cryptosporidium, although the differences were not statistically significant. Enteric viruses, coliphages and indicator bacteria were found to penetrate 2 m below the surface, although concentrations were reduced by greater than 99 percent in both cells. Less virus penetration into the sand occurred in the planted wetland versus the unplanted wetland. Water temperature was found to be the most important factor in the removal of enteric bacteria and viruses, while turbidity reduction was related to Giardia removal. These results demonstrate that significant reductions of pathogenic microorganisms can occur in constructed wetlands receiving untreated domestic wastewater with only a 1-2 day retention time.

Animals↗

PubMed2001

Removal of bacterial indicators and pathogens from dairy wastewater by a multi-component treatment system.

Microbial removal by a multi-component treatment system for dairy and municipal wastewater is being studied in Arizona, USA. The system consists of paired solids separators, anaerobic lagoons, aerobic ponds and constructed wetlands cells. The organisms under study include: total coliform, fecal coliform, enterovirus, Listeria monocytogenes, Clostridium perfringens, coliphage, Giardia lamblia and Cryptosporidium parvum. Organism removal rates from dairy wastewater varied from 13.2 per cent for fecal coliform to 94.9 per cent for coliphage. It appears that the much higher turbidity of the dairy wastewater, nearly 1,300 NTU, decreased the treatment systems' ability to remove some microbial indicators and pathogens. Information from this study can be used to determine the adequacy of multi-component treatment systems for the control of wastewater-borne pathogens, both in municipal treatment systems as well as in confined animal feeding operations (CAFO). This information also can assist municipalities and the CAFO industry in the implementation of rational and efficient treatment strategies for appropriate reuse of wastewaters.

Agriculture↗

PubMed2001

Behavior of organic carbon during subsurface wetland treatment in the Sonoran Desert.

We examined the fate of organics during wetland treatment of secondary effluent and groundwater (control) flows in parallel, research-scale, subsurface-flow (SSF) wetland raceways at the Constructed Ecosystem Research Facility (CERF) located in Tucson, Arizona. The CERF facility enabled us to distinguish experimentally among effects on effluent quality due to season-dependent processes of evapotranspiration (ET) and wetlands-derived production of organics. Organics of wastewater and wetlands origin were compared in terms of their contributions to dissolved organic carbon (DOC) in wetland effluent. Elevated temperatures and associated biochemical activities increased DOC levels in wetland effluents during summer. In other words, DOC removal efficiency was negatively correlated to temperature. The contributions of ET and wetland-derived organics to elevation of DOC in wetland effluents during summer were roughly comparable. The elevation of organic carbon concentration during wetland polishing of wastewater effluent will lead to higher levels of disinfection by-products when treated waters are chlorinated prior to reuse. Results of this work are relevant to water managers in arid regions, which may incorporate wetlands into sequential wastewater treatments leading to potable reuse of reclaimed water.

Biodegradation, Environmental↗

PubMed2001

Nutrient and heavy metal uptake and storage in constructed wetland systems in Arizona.

The Constructed Ecosystems Research Facility (CERF) was conceived in the early 1980s as a test facility to explore the potential for using plants to treat wastewater in the arid west of the USA. One of the major issues that has been identified in the use of constructed wetland technology is plant nutrient uptake and tissue storage of nutrients as well as heavy metals. Our approach to understanding plant uptake and storage has been to look at both controlled conditions in constructed systems and background concentrations in natural systems. Plant tissues have been collected and analyzed from natural systems and from controlled systems receiving either wastewater or municipal water. Plants studied included the herbaceous species Anemopsis californica (Yerba mansa), Scirpus spp. (bulrush) and Typha domingensis (cattail), and tree species Fraxinus velutina (ash), Populus fremontii (cottonwood) and Salix spp. (willow). Data indicate that uptake varies not only among plant species, but also among chemical species, depending upon water quality within the wetlands. Leaf tissues of Fraxinus, Salix and Populus, contained the lowest amounts of nutrients and heavy metals studied (Na, P, K, Cu, Pb and Zn), while the root tissues of the herbaceous plants generally had the highest concentrations.

Ecosystem↗

PubMed1994

Educating educators in GLP documentation.

Professionals in academia usually are not trained in documenting their research activities to the extent and detail mandated under Good Laboratory Practice (GLP) regulations. To assist researchers at the University of Arizona in implementing a GLP program, the university's Quality Assurance Unit (QAU) has written procedures and checklists detailing various aspects of GLPs. Since a key to the successful implementation of GLPs is comprehensive documentation in laboratory notebooks of research activities, information and guidelines are provided in a checklist format. Training seminars are also provided to discuss the use of the checklists. Checklists in conjunction with training seminars provide an important mechanism to ensure that all appropriate information has been recorded for verifiable, reproducible, and traceable documentation of project study results.

Arizona↗