Thesis--New York University. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis--New York University. / Includes bibliographical references.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

The purpose of the current study was to examine the effects of using fixed time schedules with different magnitudes of stimulus delivery as treatment for pica. A functional assessment was conducted, which indicated that pica occurred across experimental conditions and was most frequent in the absence of social stimulation or contingencies. A competing stimulus assessment was then conducted to identify stimuli that could potentially compete with pica during NCR. Subsequently, an evaluation of the effects of reinforcer magnitude on NCR as a treatment of pica was conducted. Treatment results indicated that quantity of reinforcer increased the effectiveness of leaner schedules of reinforcer delivery; however, it was not possible to fade the temporal schedule to one that would have been useful in practice. In addition, limitations and future research are outlined.

Three institutionalized profoundly retarded men were exposed to edible reinforcement schedules to determine if (a) pica could be controlled using reinforcement schedules alone, (b) if there was a functional relation between schedules of reinforcement and pica, and (c) if pica could be considered to be an adjunctive or schedule-induced behavior. Using an ABC counterbalanced design to control for order effects, the three subjects were exposed during baseline to naturally occurring reinforcement schedules; during the experimental conditions, to FI 1-min and FI 5-min edible reinforcement schedules. Results indicated that (a) the FI 1-min schedule substantially reduced the rate of pica in two men while its use resulted only in a statistically significant decreasing trend in pica in the third man, (b) that the FI 5-min schedule was no better in decreasing rates of pica than reinforcement during baseline, and (c) that there were increases and decreases in pica when exposed to certain reinforcement schedules which were consistent with the research on adjunctive behavior. It was concluded that (a) edible reinforcement schedules by themselves could lower pica rates, (b) that functional relations existed between rates of pica and reinforcement schedules, and (c) that pica may possibly constitute adjunctive behavior. The implications of these data were discussed in terms of practical applications and theoretical considerations concerning the control of pica and its relation to various reinforcement schedules. / Department of Educational Psychology

Thesis (M. Tech. (Biomedical Technology)) -- Central University of Technology, Free State, [2014] / Pica is the habitual eating of non-food substances by humans and animals. It has different subgroups and these are defined by the ingested substance. Moreover, geophagia is a type of pica that refers to the consistent eating of mostly earth and earth-like substances such as clay and soil. It is observed in both sexes, all age groups and in different ethnic groups around the world. There are many reasons people give for the practice of geophagia, such as culture, hunger and health being the most prominent. Geophagic materials differ in texture, colour and taste. Soil colour classification according to the Munsell soil classification, which uses hues, values and chroma, sometimes differ with the soil colour being noticeable with the naked eye. However, geophagic clays from Qwa-Qwa are white and contain kaoline. Geophagic materials are believed to augment mineral deficiency, especially magnesium, calcium and iron. Geophagia is practised mainly by females, especially during their child bearing years. Females are more prone to iron deficiency anaemia due to their monthly menstruation cycle. Iron deficiency is the most common cause of anaemia and is classified as hypochromic microcytic anaemia (HMA). This study focused on the health aspect of geophagia. The research question seeks to explore whether there is an association between geophagia and the haematological parameters of iron deficiency anaemia. Geophagia seems to be linked with the occurrence of anaemia, but not iron deficiency anaemia, although it is implied. It is not known if the practice of geophagia causes iron deficiency anaemia or if it is because of iron deficiency anaemia that people practise geophagia. A pilot study was done in 2007, and the results of that study prompted that this study be performed on a bigger scale. The lack of information regarding the quantity, frequency and type of geophagic material consumed the impact of geophagia on haematological parameters and the iron status of the geophagists made it important that the primary existence of the iii relationship be investigated. In addition, research to establish whether there is a relationship between geophagia and haematological parameters of iron deficiency anaemia, has not been undertaken in South Africa, especially on non-pregnant women. Geophagia seems to always be accompanied by the subject of iron deficiency anaemia and especially its prevalence in females. The bigger geophagia project was therefore an ideal opportunity to do a specific survey on geophagic women. This was a cross-sectional study, consisting of 36 control women and 47 geophagic women, aged between 18-45 years. The participants completed a questionnaire to determine the geophagic practices, which included the colour of the clay, how frequent the clay was consumed, how much was consumed and for how long it has been consumed. Nutritional status was assessed using a food frequency questionnaire. Blood was drawn to assess the haematological and iron status of the participants. The participants of the study were within the required age range, with no significant difference between the groups (p-value=0.7914). The most consumed colour of clay was white and white clay contains kaoline, which has the ability to absorb iron in the duodenum. The majority of the participants consumed 40 grams of clay on a daily basis, with most of the participants having done so for 5 years. Diet was ruled out as the cause of iron deficiency. The haematological parameters indicated that the geophagic group (43%) were inclined to have hypochromic microcytic anaemia, while a small percentage of control groups (8%) had HMA; this was revealed by the red cell parameters and red cell indices. In addition, the odds ratio for the haematological results revealed that the probability of a geophagic person developing anaemia was two times greater than that of a non-geophagic person. Platelet results partially ruled out bleeding as a cause of anaemia. The median red cell distribution width indicated that the iv geophagic group was inclined to have anisocytosis. The geophagic group was found to have iron deficiency (75%), whilst the control group had a small percentage with iron deficiency (22%), which was validated by the serum ferritin, serum iron and saturated transferrin (chemical analysis). The odds ratio revealed that the probability of a geophagic person being iron deficient is 3 times greater than that of a non-geophagic person. The strongest association is seen with iron study findings, because being iron deficient showed the highest odd ratio than the association with red cell morphology and even haemoglobin. Thus, participants were more iron deficient than suffering from iron deficiency anaemia. Inflammatory and parasitic indicators proved that inflammation and infection was uncommon in both groups, and therefore did not compromise the credibility of the iron study results. Inflammatory indicators (white blood cells, erythrocyte sedimentation rate and C-reactive protein) ruled out inflammation, whilst eosinophil count showed no indication of parasitic infection for both geophagic and control groups. To conclude, the study found that an association exists between geophagia and haematological parameters of iron deficiency anaemia amongst geophagic women in Qwa-Qwa, in that geophagic material contributes to iron deficiency anaemia.

MENVSC / Department of Ecology and Resource Management / Certain communities in Sekhukhune area are known to be practicing geophagia. Existing standard questionnaires as adopted to generate data on human geophagia included aspects on demography, socio-economics, cultural, ecological, physico-chemical aspects, indigenous knowledge and health effects of geophagic consumers. These data were gathered through distribution of questionnaires to 200 geophagic participants, of which 135 were from Ga-Nchabeleng Village and 65 from Mphanama Village. Both the Villages were based in the rural settlements in Sekhukhune area. In this study the behaviour of geophagic individuals was investigated and cytotoxicity of plant remains consumed in geophagic soils was evaluated for any toxicity. A total of 17 different geophagic sites were identified. Six geophagic sites each were from Ga-Nchabeleng Village and six from Mphanama Village. Five other sites were selected from sites where geophagia was not practiced and were recorded as the control sites. All the 17 soil samples were analysed using Munsell Soil Color charts for soil colour classification. Samples of plant remains were collected from the same geophagic sites where soil samples were collected. Due to similar plants and vegetation type from 17 different geophagic sites, a composite study was adopted. Geophagic consumers in Ga-Nchabeleng Village identified four plant species of plant remains consumed in the soil in the area and Mphanama village identified five species different from Ga-Nchabeleng plants. Samples of plant remains were grouped according to comparable features or characteristics. Sample 1 of plant remains was composed mainly of grasses; Cynodon dactylon, Aristida congesta and Eragrostis rigidior whereas sample 2 of plant remains was composed of Acacia plant; Vachellia tortilis. The two samples of plant remains were collected from Ga-Nchabeleng Village. Sample 3 of plant remains was composed of creeping, perennial weed herbs; Alternanthera pungens Kunth and Alternanthera lorentzii. Sample 4 of plant remains was composed of prominent woody plants; Combretum apiculutum, Kirkia wilmsii and Boscia albitrunca. Samples of plant remains 3 and 4 were collected from Mphanama Village study sites. Sample 5 of plant remains was the control site and composed mainly of Acacia plants; Vachellia nilotica, Acacia vii mearnsii and Vachellia tortilis and were collected from sites not used for geophagic practices. The plant remains parts mostly consumed were roots (50%) in Ga-Nchabeleng, whereas in Mphanama Village they were stems (54.5%) and the control site had leaves at 62.5%. The five samples of plant remains were recovered using physical separation method. The plant remains were washed and dried. Retch Muhle grinding machine was used to ground the samples. Methanol was used in the extraction of all the samples of plant remains. The result from the administration of the questionnaire revealed that geophagia in this area was practiced by both male and female Sepedi-speaking individuals. Ga-Nchabeleng Village had more female geophagic participants, whereas Mphanama Village had more males who have almost undergone secondary school. However, in general for the study there were more female geophagic consumers. Geophagic consumers ingest soil known locally as Mobu, Letsopa or Leraga collected mostly from the riverbanks, mountains/hills and valleys with only a few that indicated termite mounds. Geophagic consumers in the study used colour, among other things, to describe their soil of preference. The study consisted of 200 participants of whom 172 represented the geophagic group and 28 were the control group, aged between 18-65 years analysed using chi-square crosstabulation. There was no significant difference in human health effects associated with geophagia between the geophagic group and the control group. There was also no association established between soil consumption and other non-food substances between geophagic group and control group. Chi-square (χ2) analyses revealed a significant association of gender with geophagic habits (p<0.05), while there was no association of age, educational level, income source and marital status (p>0.05) with geophagic habits. Findings of the survey when two villages are combined revealed that more females (75.60%) practice geophagia compared to males (24.40%). The respondents from both study sites preferred digging technique when collecting the soil. It was established that craving was mainly the reason behind the practice in the study area. Hygiene and environmental conditions were not considered when mining viii geophagic soil as the majority of them used dirty utensils, hands for collection and non-sterile bags and tins for packaging. Some of the soils were collected close to waste dumping sites as seen whilst visiting geophagic mining sites. Majority of the consumers had little or no knowledge that the soil could be harmful or if it contained any contaminants. This sample of interviewees provided valuable information on human geophagic practices in Sekhukhune area. It became clear that this practice was entrenched in the cultural behaviour of people in the area and a need for educating them on health related aspects. The cytotoxicity of methanolic extracts of plant remains on HEK-293T cell line was evaluated using MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) assay for cell viability. The 50% cytotoxic concentration (CC50) was defined as the compound’s concentration (500, 250, 125, 62.5, 31.25, 15.625 and 7.8125 μg/ml) required for the reduction of cell viability by 50%. Evaluation of cell viability showed the methanolic extracts of plant remains on HEK-293T cell line ranged in the order of plant remains extract=3>1>4>2>5 according to their cytotoxicity activities. Plant remains extract 3 from Mphanama Village showed high cytotoxicity with a CC50 of 13.75 μg/ml, followed by plant remains extract 1 at 16.68 μg/ml, plant remains extract 4 at 58.95 μg/ml, plant remains extract 2 at 92.75 μg/ml and the control at 251.4 μg/ml, respectively. In the study only the methanolic extract was investigated for cytotoxicity using HEK-293T cell line. Further research need to be conducted on the individual plants of each plant remains to be able to have conclusive results on the cytotoxicity profile. This will indicate which specific plant part is toxic or whether they exhibit a higher CC50 only when in combination.

MESHWR / Department of Hydrology and Water Resources / Communities in South Africa have been noted to consume earthy materials such a soil among others. Geophagy is largely practised in the rural areas as opposed to urban places, and in these places the level of sanitation is low and people usual practice open defecation. The practice of Geophagia has been associated with cultural, medicinal, psychological, religious and nutritional deficiency among others. The aim of the study was to investigate the effects of open defecation on geophagic soils and water resources in Siloam village. The study also aimed to understand the reasons why people practice geophagia in Siloam village and the health effect associated with consumption of geophagic soils. To carry out the aim of the study, a questionnaire survey was conducted among women who practice geophagia between the ages of 18 and above in Siloam village. Two hundred and eighty-three (283) women were selected using snowball sampling method to take part in the study. From the (283) women, (200) women represent the geophagic group and (83) women represent the control group. The existing standard questionnaire adopted to generate data on human geophagia included aspects on demography, socio-economic, cultural, ecological, physicochemical aspects, indigenous knowledge and health effects of geophagic consumers. Participants were asked basic questions on why they practice geophagy, their geophagic material preferences, where they collect the geophagic material and other related questions. A total of twelve soil samples were collected from Siloam village, from the twelve soil samples collected eight were collected from sites known for geophagic practice and another four soil samples were collected from sites where geophagia is not practiced and the samples were used as control soil samples. All the twelve soil samples were analysed for the presence of geohelminths ova using Ammonium Bicarbonate Protocol (AMBIC protocol). The AMBIC protocol consists of four analytical procedures, namely, sample preparation, sample washing with AMBIC solution, geohelminths ova recovery through a modified zinc flotation method and microscopic analysis. vi Furthermore, a total of twelve water samples were collected from Nzhelele River and ponds water in Siloam village. From the twelve water samples, eight samples were collected close to where geophagic materials were collected and where open defecation is reported to be taking place and the remaining four water samples were collected randomly from Nzhelele river and water ponds in Siloam village and was recorded as a control group. A total of 12 water samples were analysed for total coliform and faecal coliform Escherichia Coli (E.coli) indicator using the membrane filter technique. The results from the administration of the questionnaire revealed there was prevalence in the practice of geophagia in the area. The study found that most of the villagers in Siloam consumed soil nearly on daily basis. According to the results, only women were involved in the geophagic practices in the area. Additionally, the study revealed that geophagic consumers were mainly in the age of child bearing age group and reddish and yellowish soils were the most preferred. Furthermore, the results showed that geophagic consumers in the area generally consumed soil commonly because of cravings and pregnancy, however, those who were not pregnant also consumed soil. The respondents reported that they mostly consumed clay and this material was consumed in its dry state and mostly unprocessed, if processed, it would be baked. This geophagic material was mainly found in the wild (riverbed, valley etc.); it was also found that most of the soil consumers did not know that the substances they consumed could be harmful to them. Among those who knew the consequences of consuming the material stated that soil consumption causes constipation, tooth decay, body poisoning, and abdominal pains. The results from the control group, 83 women who do not practice geophagia, aged between 18 and above, analysed using chi-square revealed a significant association of age with consuming soils (p<0.05), while there was no association of income source (p>0.05) and educational level (p>0.05) with consuming soils. Chi-square (χ2) analyses further revealed that there was no association of knowledge on the harmful nature of the substance (p>0.05), frequency of getting infections (p>0.05) and experiencing chronic illnesses (p>0.05) with frequency of consuming soils. vii The results of geophagic soils revealed the absence of geohelminths ova in the entire geophagic sample. Meaning geophagic consumers in Siloam village are not at risk of acquiring geohelminths infection which may be of potential risk to human health. However, geophagic consumers may be exposed to various other potentially hazardous biological and non-biological soil contents. The results of the water samples revealed that most of the water samples in the areas where open defection is reported to be practised had higher composition of faecal and total coliform bacteria. The composition was above the South African recommended standard for negligible risk of microbial infection. This has caused a great threat to those who consume soil collected near water resources, especially from riverbed and those who also use these water sources on their daily basis. The study recommends that geophagic consumers should continue to bake their materials before consumption as it might reduce the bacteria and toxic substances found in soils. The study also recommends that the residents of Siloam be made aware of the potential health hazards that might be posed to soil consumers and the effects of practicing open defecation near community water resources as high level of faecal coliform (E. coli) were found in the water. / NRF

MESMEG / Department of Mining and Environmental Geology / Literature indicated that several mineralogical identification studies have been carried out on clays but few have focused on the characterisation of geophagic materials from South Africa. Large quantities of earth materials are consumed daily in Mashau Village, however, their mineral content and geochemical compositions had not been determined. Moreover, though the consumption of geophagic materials is very common in the village, the associated health implications had not been addressed. Thus, the main aim of the research was to mineralogically and geochemically characterise geophagic materials commonly ingested in Mashau Village and infer on possible health implications that could result from their consumption. Questionnaires were administered to geophagists in the study area with the aim of generating data on the prevalence of geophagia and the motivations for the practice. Geophagic soils and their parent rocks (for determination of provenance) were sampled and analysed for mineralogical and geochemical content. Geophagic soil samples were subjected to the following physicochemical analyses: colour, particle size distribution, pH, cation exchange capacity (CEC) and electrical conductivity (EC). An x-ray diffractometer (XRD) was used for mineralogical analysis while major oxides and trace elements abundances were determined using x-ray fluorescence (XRF) spectrometry and laser ablation inductively coupled mass spectrometry (LA-ICP-MS), respectively. Furthermore, provenance of the geophagic materials was determined using data obtained from mineralogical and geochemical analysis. Inferred health implications were based on the physico-chemical, mineralogical and geochemical data obtained. Outcomes of the questionnaire survey revealed craving to be the motivation for geophagia in Mashau Village. Although the practice seemed to be prevalent in females of certain ages, it was certainly not limited to gender, age, educational level or socio-economic status. Out of the 20 geophagic samples, 3 samples were brown, 2 had a strong brown colour and another 2 had a light olive brown colour. Other soil colours were less common, as each colour was only observed in one sample. The sand fraction dominated the samples; the clay content was low, giving the samples a sandy clay loamy texture. The pH of the soil ranged from being slightly acidic (5.4) to being slightly alkaline. The CEC values were very high ranging from 17 t0 109 meq/100 g. vii The EC values were also high (ranging from 11.2 to 245 μS/cm) indicating a high amount of soluble salts. Mineralogical analysis of geophagic soils identified quartz, microcline, plagioclase, hornblende, dolomite, muscovite, kaolinite, smectite, talc, anatase, hematite, ilmenite, chlorite and epidote with quartz and kaolinite being the dominant minerals. Actinolite, augite, chlorite, epidote, forsterite, magnetite, muscovite, plagioclase, quartz, sepiolite and microcline were the minerals identified in rock samples. Geochemical analysis for major oxides content (SiO2, TiO2, Al2O3, Fe2O3, MnO, MgO, CaO, Na2O, K2O, P2O5 and Cr2O3) indicated that both geophagic soils and parent rocks were mainly composed of silica and alumina. Trace elements geochemistry showed a depletion of LREEs and an enrichment of HREEs in geophagic soils. The results also revealed that the REEs were enriched in the bulk fraction than in the clay fraction. Relative to the Upper Continental Crust (UCC) compositions, the concentrations of trace elements in geophagic soils were generally low. Provenance determination results showed that geophagic soils in Mashau were derived from basalts and sandstones. Majority of the samples were formed as a result of intense weathering while some were as a result of intermediate weathering. The negative health implications of the studied materials could include perforation of the colon, damage of the dental enamel and anaemia. However, geophagic materials could also be a good source of mineral nutrients and beneficial for reduction of nausea during pregnancy. / NRF