The prevalence of noise induced hearing loss at a nickel mine in Zimbabwe

M.P.H.(Occupational Hygiene), Faculty of Health Sciences, University of the Witwatersrand, 2009BACKGROUND Hearing loss from occupational exposures is a serious and widespread problem in underground nickel mining. This is a major contributor to compensable illnesses resulting not only in costly compensation but posing a serious threat to safety and also reducing the quality of working life. OBJECTIVES The objectives of this study were to identify the prevalence of noise induced hearing loss amongst underground nickel miners with at least 5 years of exposure as well as describe some risk factors for noise induced hearing loss in this occupational setting. METHODS One hundred and sixty eight underground nickel miners, or one hundred percent of eligible workers’ medical records with baseline and periodic audiograms were reviewed to identify the prevalence of noise induced hearing loss and also evaluate some of the risk factors for noise induced hearing loss namely age, duration of exposure, use of oto-toxic agents, high ambient noise levels, hearing impairment, high pre-employment noise levels, history of acoustic trauma, history of ear injury and history of previous military, hunting or police work. One hundred underground mine workers were interviewed to give insight into their pre-employment noise exposure history, non-occupational noise exposure, perceived noise levels at work, knowledge of noise hazards and their control, and the use of hearing protection devices. One hundred and sixty eight workers were observed in their various tasks over a 14 day period and their work practices were scored to identify compliance to the use of hearing protective devices as well as confirm the presence or absence of oto-toxic agents like heavy metals and solvents. Data were analyzed using the EpiInfo software version 3.4.3: 1997 as well as the online statistical package Vassar Stats. RESULTS A noise induced hearing loss prevalence of 27.4% was identified with 42% being mild hearing loss, 28.8% moderate hearing loss and 28.8% moderate to severe noise induced hearing loss. The highest noise induced hearing loss prevalence of 60% was found in the 50 and above years age group whilst 45.5% was found in the 40 – 49 year age group, 20% in the 30- 39 year age group and 5.3 % in the 20 – 29 year age group. This difference was statistically significant ( 2 1 = 19 p < 0.001). Age with a 2 = 24, p< 0.002 and duration of exposure with a 2 = 19, p< 0.001 were found to be major determinants of noise induced hearing loss at the mine. Jackhammer operation and machine operation were found to be associated with noise induced hearing loss compared to the other tasks; Tukey’s Honestly Significant Difference 0.05 = 12.23 p<0.01. The following risk factor was found to be related to noise induced hearing loss: use of quinine OR = 2.16 with CI 95% = 0.12 – 1.72. Ninety seven percent of the workers confirmed exposure to high noise levels. The knowledge of noise induced hearing loss at the mine was high (85%). Compliance with the use of hearing protective devices was found to be low with optimum usage only being achieved during the last 4 days of the 14 day observation period. CONCLUSIONS These findings attest to the relatively high prevalence of noise induced hearing loss at the mine. It can also be concluded that though the knowledge of noise induced hearing loss is high, the effective use of hearing protection still needs improvement through the implementation of comprehensive hearing conservation programs which adequately screen workers at pre-employment stage as well as consider the workers’ perceived knowledge, attitudes as well as practices in an occupational setting

An assessment of health hazards associated with the use of water mist systems as a cooling intervention in Australia

Water mist systems (WMS) installed and used for cooling ambient temperatures in public places fall within the category of premise plumbing. Premise plumbing refers to the water distribution networks that lie downstream of the water meter, and within buildings. The colonization of premise plumbing by opportunistic premise plumbing pathogens (OPPPs) such as Legionella pneumophila, Pseudomonas aeruginosa, Mycobacterium avium, Acanthamoeba and Naegleria fowleri is emerging as a challenge for public health and water quality management. Contrary to other premise plumbing features like showers and domestic taps that have been implicated in various waterborne infections, the health risks associated with WMS are not well understood. The primary aim of this thesis research was to advance understanding of the health risks associated with OPPPs in WMS used to cool ambient air temperatures for thermal comfort. A literature review was the foundation (1st study) of this research and aimed to characterise the state of knowledge about the health risks of OPPPs in WMS. The 2nd study, a questionnaire survey of 10 WMS owners and 22 Environmental Health Officers (EHOs) was conducted as formative research to understand and describe the characteristic features of WMS, as well as the knowledge, perspectives and practices of operators, and regulatory authorities that manage these systems within the context of public health legislation. Additionally, this formative research informed the research methodology for the 3rd study, a microbial investigation of 10 WMS, from which 30 bioaerosol (air), biofilm (surface) and water samples were collected, giving a total of ninety samples (N=90). Microbial samples were analysed by both culture-based (growth media) and culture-independent (polymerase chain reaction (PCR)) methods to quantify and identify the presence of 5 representative OPPPs: L. pneumophila, P. aeruginosa, M. avium and free-living amoebae (FLA) including Acanthamoeba and N. fowleri. Data on water profile parameters of water temperature, water pH and concentration of free residual chlorine, total dissolved solids (TDS) and total organic carbon (TOC) were statistically analysed to determine their impact on the colonisation of OPPP in WMS. This research identified a critical knowledge gap regarding the health risk of OPPPs in WMS (Study 1), as well as low levels of awareness amongst WMS managers and EHO’s regarding the health risks associated with WMS including: non-existent or adhoc maintenance regimes, and lack of training and education about the systems (Study 2). Furthermore, the Study 3 research demonstrated colonisation of WMS by public health pathogens of concern including of P. aeruginosa (49%), L. pneumophila serogroup (Sg) 2-14 (18%) and L. pneumophila Sg 1 (6 %), and Acanthamoeba (\u3c 3 %). On the positive, neither M. avium nor N. fowleri were detected in the WMSs investigated. Free residual chlorine was negatively correlated with all OPPPs, except for Acanthamoeba indicating that this may be a critical variable in the safe operation of WMS. L. pneumophila Sg 2-14 and Sg 1 were strongly correlated with both TDS and TOC concentration, indicating that these indicators could be used as a warning for at-risk systems, as could elevated water temperature that was positively correlated with P. aeruginosa. This research indicates that WMS present a potential health risk due to colonisation by L. pneumophila Sg 2-14, L. pneumophila Sg 1, P. aeruginosa and Acanthamoeba, and should be regulated under public health legislation for microbial contamination of air handling and water systems. Consideration should be given to reviewing existing public health legislation to capture WMS used as a cooling intervention with consideration of other emerging OPPPs besides Legionella spp., as well as development of codes/guidelines for the auditing and operation of WMS, and the upskilling and training of operators and EHOs on their associated health risks. This research has practical applications in public health, as well as commercial WMS cleaning and maintenance businesses, and other industries that use WMS for air cooling and dust suppression

Right to know: case study of South Africa

The Republic of South Africa became democratic after it succeeded to come out of a long time 'scourge' of the apartheid system which violated quite a number of human rights. One of the tools employed during that era was unnecessary secrecy which hampered citizen's right to know. When South Africa held its first election in 1994 it commenced a new South Africa without apartheid; it aimed at embracing human rights and to do away with all bad laws existing before a democratic South Africa. Consequently, the supreme law of the Country, the Constitution of 1996, entrenched human rights law amongst which is the right to access to information held by the State and another person that is required for the 'exercise and protection of human right'. This was underscored in section 32. This right started to ·appear in the interim constitution of South Africa of 1993, but was amended in the current constitution by the addition of a subsection which directed that 'national legislation must be ena~ted to give effect to this right ... ' The provision of the Constitution was effected by enacting a legislation of the Promotion and Access to Information Act of 2000) (PAIA) which put in practice the directive of the Constitution. This minor dissertation intends to make a follow up of how this right is being implemented in South Africa. In doing so, the right to know will be examined in relation to institutional and cultural secrecy. Briefly, the dissertation will seek to answer the questions: i) what are the legislative norms which have been put in place to promote and safeguard this right? and ii) are there limitations and challenges to this right? Then at the end of this dissertation, the research will present a comparative study with Tanzania, the country of origin of the present author, where the right to know is recognized by the Constitution of Tanzania but remains ineffective for lack of concrete laws to enforce the right of access to information. In a state where there is no law providing for public access to government information, this work can present a lesson from South Africa. Furthermore, it is hoped that this dissertation can contribute ideas at this moment when Tanzania is in a · transitional process of making a new Constitution

Confronting the Exclusive Dominance of Christianity in Zimbabwe’s Advanced Level Divinity Syllabus through Africanisation

In the light of the Christian religion’s exclusive dominance of the Advanced Level Divinity syllabus (9154) in present day Zimbabwe, what could be a more attractive way to also incorporate the religion of the indigenous people of Zimbabwe? In answer to this question, we will first situate the exclusion of the indigenous religion from the syllabus in the context of the colonial experience that demeaned and considered it as unqualified to be part of the syllabus. This has given rise to the exclusive dominance of the Christian religion in the syllabus. Second, the current Advanced Level Divinity Syllabus is critiqued with the objective of highlighting that its exclusive dominance by the Christian religion ought to be contested. Third, we argue that it is necessary for the government to Africanise the curriculum so that it genuinely accommodates both the indigenous people of Zimbabwe’s religion and other religions including Christianity. This is a matter of justice that seeks not only to establish parity between the religion of the indigenous people of Zimbabwe and others, but also to reject the contestable position that there are some religions that are more superior to others. Though some have attempted to critique the domi-nance of the Christian religion in the so-called ‘Religious Studies’ syllabus, no one has pointedly and systematically undertook to propose the Africanisation of the Advanced Level Divinity syllabus in present day Zimbabwe in the manner that we intend to do. The novelty of this article thus resides in its attempt to employ the Africanisation discourse in order to democratise the Advanced Level Divinity syllabus in present day Zimbabwe

Conspecific Distance-dependent Seedling Performance and Replacement of Conspecific- by Heterospecific Seedlings in Five Hardwood Species in a Temperate Forest

Poster Session

Identifying occupational health and safety risks among environmental health officers in Australia and New Zealand through an online survey

To identify the occupational health and safety (OHS) risks among environmental health officers (EHOs) in Australia and New Zealand. The objectives were to profile and compare OHS experiences from different countries and regions to gain a regional perspective on OHS hazards that impact EHOs. An online hazard exposure survey was conducted among 339 EHOs (Australia: n = 301, 88.8%; New Zealand: n = 38, 11.2%). The Mann-Whitney U test was used to compare 2 ordinal data groups, the Kruskal-Wallis H test was used for more than 2 ordinal groups, and the independent samples t test was used to compare the means of 2 independent groups where the dependent variables were normally distributed. Multiple regression techniques were used to analyze workplace incidents and age groups. A high degree of similarity in the types of workplace exposures and risk perceptions as well as concerns with organizational OHS management commitment were observed among EHOs from the 2 countries. Workplace violence and physical and psychosocial demands were the most commonly reported OHS hazards. Employer type, sex, and age group were significantly related to workplace exposure and OHS experience among EHOs in both countries. This study provides a profile of workplace exposure in the environmental health profession in the 2 countries and offers recommendations for the implementation of preventive action

Impact of Western colonial education in Zimbabwe's traditional and postcolonial educational system(s)

In this study, we employ the theory of deconstruction to challenge and reject the contention that a knowledge paradigm was non-existent among the indigenous people of Zimbabwe before the arrival of the colonisers. This is necessary because the imposition of the colonisers’ knowledge paradigm was premised on the supposed absence of an epistemology among the indigenous people. In defending the thesis that education and indeed an epistemology was in existence among the indigenous people of Zimbabwe, we submit that education is part of any given culture. In the light of this, it becomes untenable to deny the existence of education among the indigenous people of Zimbabwe before the arrival of the colonisers. Knowledge ceases to be the exclusive preserve of the colonisers. It must be noted that the imposition of the colonisers’ knowledge paradigm was accompanied by the suppression and partial destruction of the epistemology of the indigenous people. The suppression and partial destruction of the indigenous people’s epistemological paradigm is called epistemicide. The epistemicide that the colonisers inflicted on the indigenous people led to the exclusive dominance of their knowledge paradigm in the school curriculum at the expense of that of the indigenous people. In the light of this status quo, we present transformation and Africanisation as corrective to the unjustified dominance of the present day curriculum by the epistemological paradigm of the colonisers. We argue that despite the commendable proposals contained in the Report of the Presidential Commission of Inquiry into Education and Training (1999: 24) to change the curriculum so that unhu/ubuntu becomes its organising principle and to allow the co-existence of the indigenous people’s epistemological paradigm and others, in practice the dominance of the colonisers’ epistemological paradigm remains in place. We submit that the Africanisation of the curriculum is a matter of justice that demands the end of the dominance of the knowledge paradigm of the colonisers and the co-existence of the indigenous people’s knowledge paradigm and othersPhilosophy, Practical and Systematic TheologyD.Litt et Phil. (Philosophy

Opportunistic premise plumbing pathogens. A potential health risk in water mist systems used as a cooling intervention

Water mist systems (WMS) are used for evaporative cooling in public areas. The health risks associated with their colonization by opportunistic premise plumbing pathogens (OPPPs) is not well understood. To advance the understanding of the potential health risk of OPPPs in WMS, biofilm, water and bioaerosol samples (n = 90) from ten (10) WMS in Australia were collected and analyzed by culture and polymerase chain reaction (PCR) methods to detect the occurrence of five representative OPPPs: Legionella pneumophila, Pseudomonas aeruginosa, Mycobacterium avium, Naegleria fowleri and Acanthamoeba. P. aeruginosa (44%, n = 90) occurred more frequently in samples, followed by L. pneumophila serogroup (Sg) 2–14 (18%, n = 90) and L. pneumophila Sg 1 (6%, n = 90). A negative correlation between OPPP occurrence and residual free chlorine was observed except with Acanthamoeba, rs (30) = 0.067, p \u3e 0.05. All detected OPPPs were positively correlated with total dissolved solids (TDS) except with Acanthamoeba. Biofilms contained higher concentrations of L. pneumophila Sg 2–14 (1000–3000 CFU/mL) than water samples (0–100 CFU/mL). This study suggests that WMS can be colonized by OPPPs and are a potential health risk if OPPP contaminated aerosols get released into ambient atmosphere

The dynamics of land use-land cover changes for the years 1984, 1992, 2001 and 2014 in Mutasa district, Zimbabwe

Tropical woodlands in southern Africa are a primary focus of conservation efforts because they are currently under threat from rapid clearing for agriculture and human settlements. A study was carried out in Mutasa district (18°35′0″S and 32°45′0″E) in northern Eastern Zimbabwe using data that spanned the period 1984 to 2014 in order to quantify the spatial and following the conversion to agricultural lands. The land cover changes analysis for the district showed a marked decline in land areas under woodland and considerable increase in area devoted to cultivation. Temporal land-use and land cover changes in Mutasa district on the woodland and plantation forests cover.The annual rate of net cover change from natural woodland to cropland in the district was 0.8% and this was generally higher than the annual rate of net cover changes in tropical Africa which averages 0.36%. The period from 1992 to witnessed the highest daily conversion rate of commercial farm land under woodland (miombo) and forest plantations to cropland of about 3 ha per day and this also coincided with the Fast Track Land Reform Programme which started in 2000