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To assess the significance of pollutants released into the environment it is necessary to determine both the extent of contamination and the biological effects they give rise to. This research is based on a tiered system, which commences with conventional analytical chemistry (gas chromatography), followed by the development, evaluation and application of rapid and simple immunochemical techniques and, finally, the integration of chemical and biological markers to assess pollution. GC-ECD/FID/MS have been used to investigate the status of chemical contamination of the Black Sea by organochlorine residues, hydrocarbons and faecal sterols. Useful information is provided and problems with e.g. HCHs and sewage contamination are highlighted. Contamination by DDTs, PCBs, "total" hydrocarbons and PAHs is also reported. Next, these techniques are used to develop rapid screening methods. Four distinct applications of immunochemical techniques are presented. Initially, the BTEX RaPDD Assay® ELISA is evaluated to detect semi-volatile hydrocarbons in contaminated groundwater. Although overestimating concentrations when compared to GC-FID/PID, results are well correlated. Secondly, the effectiveness o f the BTEX and c-PAH RaPID Assay® to detect hydrocarbons in sediments is tested. Once again, good agreement with GC-FID/MS confirms the ELISA to be a useful screening protocol to focus more expensive high-resolution analytical techniques. The adaptability and applicability of an ELISA (PCB RaPID Assay®) method in measuring "total" PCB levels in mussel tissue is demonstrated. An underestimation of concentrations, despite of covariability between ELISA and cGC-ECD, is discussed. Next, ELISA (RaPID Assay®) and fluorometry were successfully applied to quantify PAH metabolites in crab urine as a measure of exposure. HPLC analyses indicated that conjugate PAH metabolites were dominant in urine of crabs exposed to pyrene. Differences could also be identified between crabs taken from clean and contaminated sites. Finally, an integration of chemical and biological techniques is used to investigate contamination and effects in mussels within a pollution gradient. Results indicate a correlation between micronucleus formation, heart rate and PCB and PAH level.

M.Tech. / A study to determine the occurrence of fungi and their mycotoxins in rural food and their effect on human health was carried out at N’wamitwa (Tzaneen), a rural area of Limpopo province (South Africa). Fifty-eight maize and twenty-nine bambara nuts samples were collected from selected house holds and taken to the storage facilities of the Food, Environment and Health research group (FEHRG) laboratory at the University of Johannesburg for analysis. The samples were analysed for moisture content, fungal infestation, mycotoxin contamination and their toxicity. The moisture content of the samples were at a range of 3-20% moisture. Fungi which included species of the genus Aspergillus, Fusarium and Penicillium were detected at all moisture ranges but more dominant in samples with higher moisture levels. Fungi in this study were able to produce mycotoxins which included deoxynivalenol (DON), zearelenone (ZEA), aflatoxins (AFs), T2- toxin, fumonisins (FBs), ochratoxin A (OTA) and citrinin. The most dominant toxins in maize samples quantified by VICAM were AFs followed by DON, FBs and lastly ZEA and in bambara nuts were FBs followed by DON, AFs and ZEA. HPLC was able to detect higher concentrations of FBs than VICAM. The toxins were then tested for their toxicity using human lymphocytes and the most toxic was DON followed by AFs, FBs and lastly ZEA. Three vials of the same toxin with different concentrations, one with the highest and others with the middle and the lowest concentrations were used to treat the human lymphocytes.

Mycotoxins are secondary metabolites of fungi, which may contaminate animal feed and human food at all stages of the food chain. This has become a global concern and considered an important risk factor mostly for human and animal health. The aim of this project was to elucidate the general health and productivity of domesticated animals in selected rural areas of the Limpopo Province in relation to fungi and mycotoxin and find out possible solutions to avoid in the future further exposure and to improve animal production in rural areas. A total of 95 animal fresh faeces (50 from Mapate and 45 from Nwanedi districts), 50 feed samples (24 from Mapate and 26 from Nwanedi) and 50 fresh milk samples from cattle and goats were screened for fungi and mycotoxin contamination. The multi mycotoxin extraction method was used, followed by thin layer chromatography, also the VICAM immunoaffinity clean up, high performance liquid chromatography, gas chromatography mass spectrophotometry and the ELIZA enzyme linked kit method were used for further mycotoxin determination and quantification. The results obtained from this study revealed that species of Aspergillus, Fusarium and Penicillium fungi contaminated both feed and animal faeces samples. The species Aspergillus niger, A. clavatus, A. flavus, A. fumigatus, Fusarium verticillioides, F. graminerium and F. proliferatum were the most prevalent fungi. Fumonisin B1 and B2, aflatoxins B1, zearalenone and deoxynivalenol (DON) were found in animal feed. Fumonisins B1 and B2 were also found in faecal samples which indicated animal exposure to these mycotoxins. Cattle were the most exposed as compared to goats and pigs. In addition, aflatoxin M1 and traces of fumonisin B1 was detected in cattle and goats milk samples collected from both Mapate and Nwanedi districts. Late harvesting and poor handling of crops during storage seemed to be the reason for the results indicating feed contamination with high levels of fungi and mycotoxins. Daily exposure to this contaminants may influence or/and induce several symptoms such as dermatosis, immunosupression, liver and oesophageal cancer in both animal and human being. There is an urgent necessity to teach rural populations simple and cheap methods of crops storage and techniques to prevent feed and food contamination. / Prof. Mike F. Dutton Mr. F. Eric Van-Zyl

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Medicine in the branch of Anaesthesiology Johannesburg, 2013 / Background: Microbial contamination of multi-dose vials is one of the mechanisms by which transmission of pathogens to patients can occur in anaesthesia. Common practice at Chris Hani Baragwanath Academic Hospital (CHBAH) is to use boluses of a self-prepared, multi-dose phenylephrine solution (referred to as the solutions) to treat hypotension, due to the vasodilatory effects of a spinal anaesthetic, in stable patients undergoing a caesarean section. Aims: The aims of this study were to determine if there was microbial contamination of the solutions used at CHBAH and to evaluate if appropriate labelling and aspiration practices were adhered to with regard to the solutions A sample was collected and the labelling data was documented from the solutions found in the obsteric theatres at CHBAH over a period of three months. The samples were sent to a laboratory for microbial investigation. Microbial contamination was identified in seven of 110 (6.36%) samples collected from the solutions. The name of the solution was indicated on all 110 (100%) containers and the concentration of the solution was indicated on 106 (96.36%) containers. The date the solution was prepared was indicated on 82 (74.55%) containers and the time the solution was prepared was indicated on 63 (57.27%) containers. Only nine (8.18%) of the healthcare workers that prepared the solutions confirmed it by placing a signature on the container. Labelling data was written directly on all 110 (100%) containers and a spike device was used in 71 (64.54%) containers. This study demonstrated microbial contamination of the solutions and that safe injection practices were not adhered to when intravenous medications were prepared and administered. This is important at CHBAH since a large proportion of South African patients are immunocompromised and susceptible to opportunistic infections. Inappropriate labelling of medications is a cause of medication administration errors and this may have serious legal implications for the anaesthetist.

Spring water bottled and sold for human consumption can only be subjected to certain treatment processes such as separation from unstable constituents by decantation, filtration and aeration, ultraviolet irradiation and ozonation. A spring water distribution system in the Western Cape, South Africa was experiencing microbiological problems. The aim of the study was to investigate bacterial contamination in the spring water distribution system and the application of bioremediation as treatment technology. Sampling at various points in the spring water distribution bottling system started in February 2004 and continued until November 2004. The acceptable microbiological limits for bottled spring water clearly states that the total viable colony count should be < 100 organisms per ml of water. Analysis of samples by the heterotrophic plate count (HPC) technique indicated significantly (p < 0.05) high counts which did not conform to the microbiological limit. The heterotrophic plate counts recorded for weeks one, four, eight & 46 in the final bottled water (Site J) were 3.66 x 107 cfu/ml, 9.0 x 106cfu/ml, 2.35 x 107 cfu/ml and 5.00 x 104 cfu/ml, respectively. The total cell counts [Flow cytometry analyses (FCM)] recorded for week one, four, eight & 46 in the final bottled water (Site J) were 5.44 x 107 microorganisms/ml, 8.36 x 107 microorganisms/ml, 9.09 x 107 microorganisms/ml and 5.70 x 107 microorganisms/ml, respectively. The higher viable total cell counts(FCM) indicate that flow cytometry was able to detect cells in the water sample that enter a viable but not culturable state and that the heterotrophic plate count technique only allowed for the growth of the viable and culturable cells present in the water samples. This indicated that the HPC is not a clear indication of the actual microbial population in the water samples. It could be concluded that FCM technique was a more reliable technique for the enumeration of microbial populations in bottled water samples. Various organisms were identified by means of the Polymerase Chain Reaction (PCR) using 16S rRNA specific primers. Purified PCR amplicons were sequenced and Phylogenetic trees were constructed. Neighbour-joining phylogenetic tree analysis of the bacterial species present in the water samples was performed. The dominant bacterial isolates that were sequenced from the various water samples throughout weeks one, four, eight and 46 were Bacillus sp. and Enterobacteriaceae. The pathogenic species isolated throughout the sampling period included Escherichia sp., Pseudomonas sp., Shigella boydii, Bacillus and Staphylococcus sp. A laboratory-scale bioreactor was constructed and water samples were analysed over a period of two weeks. Water samples were analysed using FCM and Direct Acridine Orange Count (DAOC) in conjunction with epiflourescence microscopy (EM). The FCM counts ranged from 1.53 x 107 microorganisms/ml in the initial sample (Day 0) to 1.16 x 107 microorganisms/mℓ in the final sample (Day 13). The results indicated a 24% decrease in the microbial numbers however, it was still above the limit of < 100 organisms/ml as set out by the South African Standards of Bottled Water, (2003). The total cell counts obtained by the DAOC method ranged from 1.43 x 106 microorganisms/ml to 9.54 x 105 microorganism/ml on day 13 (final). The results indicated a 33% decrease in microbial numbers. The total cell counts analysed by flow cytometry fluctuated throughout the sampling period. The total cell counts obtained from the DAOC method were lower in all the water samples when compared to the total counts obtained by flow cytometric analyses. Even though the FCM counts fluctuated throughout the sampling period, results clearly show that the FCM method yielded more accurate data for total cell counts than the DAOC method. Due to external environmental conditions such as changes in the weather conditions the results fluctuated and the final results clearly indicated that further studies are required to optimise the bioreactor system for its application in the spring water industry.

by Wong Siu Kay. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 172-175). / Chapter PARTI : --- Naphthalene contamination in Milk Drinks / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 : --- Methods of determination of Naphthalene in Milk and Packaging Materials --- p.6 / Chapter Chapter 3 : --- Prediction Method I - Simulation --- p.15 / Chapter Chapter 4 : --- Prediction Method II- Mathematical Modelling --- p.24 / Chapter Chapter 5 : --- Atmospheric Effect I - Naphthalene Vapour in Air --- p.31 / Chapter Chapter 6 : --- Atmospheric Effect II- Aromatic Hydrocarbons in Air --- p.44 / Chapter Chapter 7 : --- Naphthalene Contamination In Solid Foods --- p.58 / Chapter Chapter 8 : --- Migration of Naphthalene in other Types of Polymers --- p.69 / Chapter Chapter 9 : --- Further Studies --- p.76 / Reference --- p.31 / Appendix I --- p.88 / Chapter Part II : --- General Study of Plasticisers Migration into Food / Chapter Chapter 1 : --- Introduction --- p.91 / Chapter Chapter 2 : --- Survey of Plasticisers Level in Food Contact Materials --- p.100 / Chapter Chapter 3 : --- Survey of Plasticisers Level in Foodstuff --- p.119 / Chapter Chapter 4 : --- Mathematical Modelling --- p.139 / Chapter Chapter 5 : --- Effect of Microwave Heating --- p.159 / Reference --- p.172 / Appendix II --- p.176

A three-part project was devised to investigate the origins of and potential methods to reduce the risk of occupational exposure to cytotoxic drugs. The first phase involved researching the current decontamination methods applied in UK hospital pharmacies, which manipulate cytotoxic drugs. The second phase evaluated practical decontamination methods, and the third phase investigated one intervention aimed at reducing or preventing contamination occurring in an isolator. A questionnaire was sent out to ASU managers in NHS hospital pharmacies to gain information about the disinfection and decontamination procedures and products used. The practical decontamination methods investigated were mechanical removal and degradation by detergents (pH range from 1.7 - 13.2) and cleaning agents, and degradation by vaporised hydrogen peroxide. Analytical methods were developed and validated to recover and quantify the amount of cytotoxic marker drug remaining after the decontamination tests carried out in phase two, and to recover and quantify cytotoxic surface contamination from various surfaces in phase three of this work. This composed an attempt to evaluate the effectiveness of a closed-system e.g. PhaSeal® device for fluid-transfer, in reducing contamination produced from the compounding of cytotoxic drugs in an isolator. The detergents and cleaning agents were effective in removing or reducing cytotoxic surface contamination. Alkaline detergents caused degradation of doxorubicin (maximum 81% at pH 13.2 after 1 hour exposure); the other detergents tested did not xi x degrade the cytotoxic drugs investigated. Exposure to vaporised hydrogen peroxide (1.6g min-1 for 2 hours) caused the degradation of cyclophosphamide (98.9%), 5-Fluorouracil (29.3%), doxorubicin (71.0%) and epirubicin (65.9%) when exposed in pharmaceutical diluents. The closed-system (PhaSeal®) device was effective in reducing contamination produced in an isolator from the compounding of cytotoxic drugs. The risk posed by handling and manipulation of cytotoxic drugs and products to the operator and the environment may be reduced, if not eliminated by considering additional approaches to the methods already in place. Firstly, the application of effective decontamination methods; and secondly, by using an effective closed-system, for example the PhaSeal® drug transfer device in a controlled environment.

by Wai Yin Karen Fong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves [106]-[110]). / Abstract --- p.2 / Acknowledgments --- p.3 / Dedication --- p.4 / Abbreviations --- p.5 / Table of Contents --- p.7 / Chapter Chapter 1: --- Introduction --- p.11 / Chapter 1.1 --- Overviews of packaging materials --- p.11 / Chapter 1.2 --- Source of contamination --- p.14 / Chapter 1.2.1 --- Contamination from packaging materials --- p.15 / Chapter 1.2.2 --- Contamination of plasticisers from packaging materials and its effect --- p.16 / Chapter 1.3 --- Classification of commercial plasticisers --- p.19 / Chapter 1.3.1 --- Application of plasticisers --- p.20 / Chapter 1.4 --- Analysis of the plasticisers in the food packaging films --- p.22 / Chapter 1.5 --- Analysis of plasticisers in food using isotope dilution technique --- p.22 / Chapter Chapter 2 --- : Instrumentation and Analytical methods --- p.25 / Chapter 2.0 --- Instrumentation --- p.25 / Chapter 2.1 --- Gas chromatography --- p.25 / Chapter 2.2 --- Detector --- p.26 / Chapter 2.2.1 --- Flame ionisation detector --- p.26 / Chapter 2.2.2 --- Mass spectrometer --- p.27 / Chapter 2.2.2.1 --- Ion trap detector --- p.28 / Chapter 2.2.3 --- Ionisation mode --- p.33 / Chapter 2.2.3.1 --- Electron ionisation (EI) --- p.33 / Chapter 2.2.3.2 --- Chemical ionisation (CI) --- p.34 / Chapter 2.4 --- Analytical methods --- p.36 / Chapter 2.3 --- The use of combined GC/MS in the analysis of plasticisers --- p.36 / Chapter 2.3.1 --- Identification by GC/MS --- p.37 / Chapter 2.3.2 --- Qualitative MS --- p.37 / Chapter 2.3.3 --- Quantitative MS --- p.39 / Chapter 2.3.3.1 --- Isotope dilution technique --- p.40 / Chapter Chapter 3: --- Analysis of plasticisers in food packaging materials --- p.41 / Chapter 3.1 --- Introduction --- p.41 / Chapter 3.2 --- Experimental and Instrumental --- p.42 / Chapter 3.2.1 --- Reagents --- p.43 / Chapter 3.2.2 --- Materials --- p.43 / Chapter 3.3 --- Identification of food packaging materials --- p.43 / Chapter 3.3.1 --- Fourier transform infrared spectrometry --- p.44 / Chapter 3.3.2 --- Burning test --- p.45 / Chapter 3.3.3 --- Solvent dissolution method --- p.46 / Chapter 3.4 --- Extraction of plasticisers from the packaging materials --- p.49 / Chapter 3.4.1 --- Chloroform extraction --- p.50 / Chapter 3.4.2 --- Solvent reflux method --- p.50 / Chapter 3.5 --- Results and discussion --- p.51 / Chapter 3.5.1 --- Precision test --- p.51 / Chapter 3.5.2 --- Calibration curve --- p.52 / Chapter 3.5.3 --- Detection limit --- p.54 / Chapter 3.5.4 --- Recovery --- p.54 / Chapter 3.6 --- Survey of the level of plasticisers in food packaging materials --- p.55 / Chapter 3.7 --- Conclusion --- p.66 / Chapter 4.0 --- Analysis of plasticisers in foods --- p.67 / Chapter 4.1 --- Introduction --- p.67 / Chapter 4.2 --- Experimental and instrument --- p.67 / Chapter 4.2.1 --- Reagents --- p.68 / Chapter 4.2.2 --- Materials --- p.68 / Chapter 4.3 --- Analysis --- p.69 / Chapter 4.3.1 --- selection of stable isotope labelled analogues --- p.69 / Chapter 4.3.2 --- Synthesis of deuterated internal standard --- p.70 / Chapter 4.4 --- Extraction of foods --- p.71 / Chapter 4.4.1 --- Clean up method --- p.73 / Chapter 4.4.2 --- Quantitation --- p.77 / Chapter 4.5 --- Results and discussion --- p.82 / Chapter 4.5.1 --- Precision test --- p.82 / Chapter 4.5.2 --- Calibration curve --- p.84 / Chapter 4.5.3 --- Detection limit --- p.85 / Chapter 4.5.4 --- Survey of the level of plasticisers in food --- p.86 / Chapter 4.6 --- Conclusion --- p.91 / Chapter 5.0 --- Analysis of plasticisers in food by EI and CI method / Chapter 5.1 --- Introduction --- p.93 / Chapter 5.2 --- Experimental and Instrumental --- p.94 / Chapter 5.2.1 --- Reagents --- p.95 / Chapter 5.2.2 --- Materials --- p.95 / Chapter 5.3 --- Extraction of foods --- p.95 / Chapter 5.3.1 --- Clean up method --- p.95 / Chapter 5.4 --- Result and discussion --- p.95 / Chapter 5.4.1 --- Precision test --- p.95 / Chapter 5.4.2 --- Calibration curve --- p.97 / Chapter 5.4.3 --- Detection limit --- p.99 / Chapter 5.4.4 --- Survey of plasticisers in food by EI and CI method --- p.100 / Chapter 5.4.5 --- Paired t-Test --- p.103 / Chapter 5.5 --- Conclusion --- p.104 / Chapter Chapter 6 --- Conclusion --- p.105 / Bibliography --- p.106 / Appendices : / Chapter 1 --- The mass spectrum of DEP --- p.i / Chapter 2 --- The mass spectrum of DIBA --- p.i / Chapter 3 --- The mass spectrum of DIBP --- p.ii / Chapter 4 --- The mass spectrum of DBP --- p.ii / Chapter 5 --- The mass spectrum of DBS --- p.iii / Chapter 6 --- The mass spectrum of ATBC --- p.iii / Chapter 7 --- The mass spectrum of BBP --- p.iv / Chapter 8 --- The mass spectrum of DEHA --- p.iv / Chapter 9 --- The mass spectrum of DPOP --- p.v / Chapter 10 --- The mass spectrum of DEHP --- p.v / Chapter 11 --- The mass spectrum of DCHP --- p.vi / Chapter 12 --- The mass spectrum of DOAZ --- p.vi / Chapter 13 --- The mass spectrum of DOS --- p.vii / Chapter 14 --- Calibration curve of GC/FID --- p.viii / Chapter 15 --- Calibration curve of GC/MS (magnum) --- p.xi / Chapter 16 --- Calibration curve of GC/MS (GCQ) --- p.xiv

Thesis (Ph. D.)--University of Rhode Island, 2005. / Typescript. Includes bibliographical references (leaves 129-143).